Untitled

LIBRARY OF THE UNIVERSITY OF CALIFORNIA. 

GIPT 

MISS ROSE WHITING. 

Deceived September, i8g6. 

Accession No.#J} y*J0 3- 

Class No.

A POPULAK 

TREATISE 0^ GEMS

A POPULAR 

TREATISE ON GEMS, 

IN REFERENCE TO THEIR 

SCIENTIFIC VALUE: 

A GUIDE FOR THE TEACHER OF NATURAL SCIENCES 

THE 

LAPIDARY, JEWELLER, AND AMATEUR: 

TOGETHER WITH A 

DESCRIPTION OF THE ELEMENTS OF MINERALOGY, AND ALI 

ORNAMENTAL AND ARCHITECTURAL MATERIALS. 

BY 

DK. L. FEUCHTWANGEK, 

H 

AND MINERALOGIST, MEMBER OF THE NEW YORK LYCEUM 0V 

AT. HIST., AMERICAN ASSOO. OF SCIENCE, OF THE 

MINEBALOGICAL SOCIETIES OF JENA, 

ALTBNBURG, ETC. 

THIRD EDITION. 

NEW YOEK: 

PUBLISHED BY THE AUTHOR, No. 55 CEDAB ST. 

1867.

Entered according to Act of Congress, in the year 1S69. 

BY DK. L. FEUCIITW^NGEE, 

In th* Clerk's Office of the District Court of the United States for the Southern 

District of New York. 

JOHN W. AMEBMAN, PRINTKK, 

No. 4T Cedar St., N. Y.

PREFACE 

IN none of the numerous works on Mineralogy that have 

lately been published, have GEMS been treated in a manner 

commensurate with the important rank which they hold in the 

mineral kingdom. The author of this treatise published in 

1838 a small work on Gems, which was well received by the 

scientific world. As that edition was soon disposed of, the 

author intended to issue a larger and improved edition, but 

close application to his legitimate pursuits prevented him from 

accomplishing that object. In 1851 he visited the London 

Exhibition, where the treasures of the mineral kingdom, and the 

profusion of brilliant and costly gems from all quarters of the 

globe, formed a collection such as had never before been wit- 

nessed ; and he then resolved to embody the facts which he 

had there collected in a ne\v work on Gems, which he has been 

encouraged to publish by the solicitations of numerous teachers 

and jewellers, who had used his former treatise as a work of 

reference, and who wish to have a work that will impart useful 

and correct information in regard to tjie locality and value of 

Gems in the present state of scientific knowledge. As a work 

on Gems would be incomplete without a treatise on Mineralogy, 

and as the author did not wish to enter into details foreign to 

his subject, he was at a loss how to commence ; 

but on consult- 

ing the recent works on the Elements of Mineralogy of Pro 

Nichols and Zimmerman, he was conviiu:<

PREFACE. 

of the leading principles of Mineralogy was indispensable, as ar 

introduction to his main design ; 

and that Crystallography, the 

mother of Gems, should be explained, before treating them when 

prepared for the dealer or wearer : he concluded, therefore, to 

commence his treatise by following the Terminology of Nichols' 

Elements of Mineralogy, of which he copied the greater part, 

along with some remarks of Dufresnoy, from the study of whose 

great work on Mineralogy he derived much valuable informa- 

tion. He feels it incumbent on him publicly to acknowledge 

his obligations to the author of the Elements of Mineralogy, 

for the concise and lucid descriptions contained in the first 

part of that work, which should be read by every student of 

Mineralogy. In the second part of this work, which treats of 

Gems, the author has followed his own system in their classifi- 

cation j that is, he has arranged them according to their in- 

trinsic value, and not alphabetically, as has been done by some 

authors, nor as oxydized stones a system adopted by others. 

The diamond is placed at the head of the whole class of Gems, 

and the others follow in the order of their commercial value. 

Some minerals which are not properly Gems have been in- 

cluded in the list, either on account of certain specific characters 

which they possess, or their applicability to some useful purpose. 

Many mineral substances which belong properly to the geolog- 

ical or economical department of the science of mineralogy, 

have been treated in this part of the work ; but they occupy 

so important a position in the economy of life, that their intro- 

duction cannot be regarded as an intrusion. Reference is here 

made to the detailed account of coal, marble, granite, and 

sienite are they not as valuable as the Gems described in this 

treatise ? are they not the foundation on which is to be reared 

the opulence of future generations? have they not already 

contributed to the aggrandisement of the United States, the 

most enterprising nation on the globe ? 

The revenue arising from he annual production of eight

PREFACE. 7 

million tons of coal is not inconsiderable. The marble of the 

country, which is just beginning to be developed, bids- fair to 

compete with that of any other country, .and to revolutionize 

the civilized world. The marble from California, that from 

the quarry lately discovered in Pennsylvania, the Leocadia 

Breccia, the Verde- Antique of Vermont, and the white marble 

from Canaan, Conn., which is used in the construction of the 

Fifth Avenue Hotel, Madison Square, N. Y.,*are referred to as 

illustrations. Are not the sienites and the granites which 

have, been quarried for the last fifty years; and which have been 

used in the erection of all our public edifices, really 

as valuable 

as Gems ? 

Few persons were aware, until recently, of the existence of 

fancy (variegated) marbles in this country ; 

and Italy, Greece, 

and Ireland furnish the materials for ornamenting fine houses 

and cemeteries, because our own resources have been overlooked, 

or not developed. What will be the condition of things fifty 

years hence, when the fine arts will occupy as prominent a position 

in this country as in any other, and when wealth and 

taste will compete with the arts and sciences for the ascendency ? 

The Almighty has converted the vegetables of the forest into a 

mineral substance, the animals of the sea into building-stone, 

and endowed man with the faculty of exploring and developing 

the hidden treasures of nature, and this faculty will soon render 

this country independent of all other nations. The principal 

aim .of the author has been to explain not only the useful, but 

also the ornamental mineral substances, and such compositions 

called mosaics as are prepared from them, and he is indebted 

for much valuable information pertaining to this branch of the t 

subject to the Jury Report of the London Exhibition.

PEEFACE TO THE THIED EDITION. 

THE publication of 1859 having been exhausted for several years, 

the numerous applications from booksellers for a supply have induced 

the author to issue another edition, and to improve it in adding 

an Appendix to the work on such subjects which, in his judgment, 

was considered indispensable ; it was to give to his readers 

the chronology of mineralogical knowledge, from its first dawn to 

the present day, and with much perseverance and labor he accomplished 

this task. It was thought advisable and useful to add tables 

of the distinguishing characteristics of gems, so as to have at one 

glance a condensed survey of the physical and chemical characters 

of all the gems, and they were, therefore, copied from Mr. Harry 

Emanuel's late work on Diamonds and Precious Stones, as also 

many remarks on the value and market prices of gems, etc. 

The author was requested to have his likeness placed in front of 

the work, and reluctantly complied with it but while ; 

doing so, he 

is satisfied that his numerous friends on the Pacific will consider it 

acceptable. On account of the latter change, the former frontispiece 

had neeessarily to be altered, and the best place was Part III., where 

the individual gems were treated on page 183, but the Kohinoor 

and Zircon crystals were deemed best to be replaced by other gems, 

which his friend, Mr. G. CX Newcomb, kindly furnished him for copying 

; they are a large Ruby spinelle of 100 carats weight, and a 

large Hyacinthe, and a beautiful precious Opal, which were photographed 

along with various gems and executed very faithfully. 

In the present great Paris Exposition, according to the official 

catalogue, a great many valuable gems are mentioned, such as the 

Crown Jewels of France those from the ; Queen of Sweden ; also 

those of Russia and from the various ; 

English, German, Turkish 

and French jewellers ; also, a Brazilian Topaz, of 3 Ibs. weight, 

7 inches long and 4f inches wide, has recently been deposited. 

The extensive display of Corals, one set of which was valued at 

$2,300, and many others, but, for want of a detailed description, 

could not be enumerated in this Treatise. 

The author had latterly occasion to examine at the jewelry store 

of Messrs. Bishop & Rein, under the Fifth Avenue Hotel, New-York, 

a beautiful white Brilliant, of 14 carats weight, and a great variety 

of splendid pink Corals. Also, at Doucet's store, Montreal, from 

Thunder Bay, Lake Superior, large masses of Amethysts, weighing 

several hundred pounds. 

The author takes pleasure in recommending the Heliographic 

Engraving Company, under the superintendence of Baron Egloffstein.; 

the author's likeness having been executed by them with 

much skill. 

Praise is also due to Mr. Schnapauff, who much improved the 

oojoring of the gems, many of them true to nature. 

With these few remarks, the author commits herewith the present 

edition to the reader, and trusts it may prove useful and instructive, 

which will ever gratify the public servant, 

LEWIS FEUCHTWANGER, M. D. 

NEW-YORK, June 1, 1867.

INTRODUCTION 

CONTENTS. 

PAET I. 

TERMINOLOGY. 

PAG* 

13 

CHAPTER I. Form of minerals 19 

" II. Physical properties of minerals 75 

" in. Chemical properties of minerals 102 

" 

IV. Classification of minerals 129 

PAET II. 

THE GEMS. 

Division of Gems 135 

Color, gravity, and hardness 137 

Chemical characters 139 

Composition 

Artificial production of Gems and Minerals 140 

Geological characters 145 

Geographical distribution 146 

Practical division and nomenclature 147 

History of Gems 148 

Sculpture in Gems 151 

On Grinding 

153 

Forms of the diamond 161 

Form of Gems 163 

Common lapidary ....... 166 

Engraving 

Sawing and drilling Gems fc 168 

1* 

139 

166

10 CONTENTS. 

Grinding and polishing materials 

PAGB 

168 

Heightening the color of Gems 169 

Setting of Gems 171 

Cleaning Gems 172 

Imitations of Gems 172 

Price of, and trade in Gems '. . . . 181 

Gems for optical purposes 

181 

PAET III. 

CONSIDERATION OF THE INDIVIDUAL GEMS. 

Diamond 183 

Corundum 214 

Sapphire 

214 

Common corundum 223 

Chrysoberyl, Cymophane 225 

Spinelle 

Topaz 

Euclase 

Emerald 235 

Beryl, aquamarine 

240 

Zircon, Hyacinth, Jargon 

244 

Garnet 247 

Essonite, Cinnamon -stone 253 

Tourmaline, Kubellite, Siberite 254 

Quartz 

259 

Kock crystal 

260 

Amethyst 

266 

Common quartz rose quartz 269 

" 

" 

" 

" 

Cat's eye 

Prase 

270 

271 

" " Avanturine 272 

Jasper 

273 

Hornstone .....' 277 

Chalcedony 

277 

Carnelian 279 

Heliotrope, Bloodstone 282 

Agate 

283 

Chrysoprase 

292 

' 

227 

229 

234

CONTENTS. 11 

Chrysolite, Peridot, Olivin 

PAGB 

294 

Isolite 297 

Opal 

Fire opal 

Hydrophane 

Semi-opal m 306 

Cachelong 

307 

Jasper opal 

308 

Obsidian 309 

Axinite 

% 

311 

Felspar 

312 

Adularia 312 

Common felspar 

315 

Labrador 317 

Hypersthene 

320 

Idocrase 321 

Hauyne 

Lapis lazuli 322 

Kyanite, Sappare, Disthene 327 

Turquoise 

329 

Natrolite 332 

Fluor spar , 333 

Malachite .336 

Satin spar 

Alabaster 341 

Amber , 343 

Jet 353 

Meerschaum 357 

Lava , 360 

Jade ; 361 

Serpentine -. 362 

Marble 364 

Stalactite and Stalagmite 

380 

Egyptian and Italian marbles 382 

American marbles 383 

Pisolite and Oolite 386 

Rock of Gibralter 386 

Apatite 

Lepidolite 

Mica.. . 389 

299 

304 

305 

322 

340 

387 

389

12 CONTENTS. 

Pyrites ... .. 

PA 08 

390 

Kose manganese 

391 

Porphyry 

391 

Sienite 393 

Granite 396 

Pearls , 400 

Corals ......... 419 

Shell cameos : 425 

Mosaic and Pietra Dura.. . 426

INTRODUCTION. 

THE natural productions of our globe may be considered 

either in their original or in their changed condition. They 

are divided into two general classes which are determined, 

either by certain characters that do not require explana- 

tion or investigation, or, by the external appearances 

which are presented by them in their altered condition, 

and by investigating the causes which produced the changes 

of form or state. 

In the former case, the science is called Natural History; 

in the latter, Natural Philosophy. 

Natural History, considered in reference to the original 

properties of natural productions, must, therefore, be di- 

vided into organic and inorganic: to the former belong 

Zoology and Botany ; 

to the latter, Mineralogy. 

Botany and Zoology comprise bodies possessed of vitality, 

or beings which, increasing by the absorption of nutritive 

substances, mature after a certain period ; their parts are 

dependent upon each other, and they cannot be separated 

without destroying the integrity of the individual, which, 

after a certain period, loses its vitality and ceases to exist ;

14 INTRODUCTION. 

or death ensues, decomposition takes place, and the original 

being is entirely destroyed. 

Mineralogy, on the contrary, comprises 

those natural 

objects which are not possessed of life, and do not increase 

by absorption, but merely by accretion that is, by an ex- 

ternal growth or addition without any assimilation ; they 

do not mature by age ; 

their parts may be separated with- 

out destroying their individuality; and their formation 

being the result of chemical attraction, they are not liable 

to decomposition. 

Mineralogy comprises two distinct sciences : Mineralogy 

proper, which treats of the simple minerals, either as inde- 

pendent bodies, or in relation to the characters which serve 

to determine and distinguish them ; and G.eology, which 

considers both simple and mixed minerals as they exist in 

nature, and in their dependent relations with soils and 

rocks. Mineralogy describes the individual qualities of the 

several mineral species, Geology treats of them only- as 

associated in the structure of the earth. 

The characters of minerals are ascertained by their morphological, 

physical, and chemical properties. That part of 

Mineralogy which treats of the application of minerals to 

the different arts, is called Economical Mineralogy ; miner- 

als used by lapidaries in making ornaments, are called Gems. 

Geometry, Physics (Natural Philosophy), and Chemistry, 

form the base for the study of Mineralogy, as without a 

knowledge of those sciences, the true characters of a min- 

eral cannot be ascertained. 

Geology is, according to Lyell's explanation, 

the science 

which investigates the successive changes that have taken 

place in the organic and inorganic kingdoms of nature. It

INTRODUCTION. 15 

inquires into the causes of these changes, and the influence 

which they have exerted in modifying the surface and ex 

temal structure of our planet. By these researches into 

the state of the earth and its inhabitants at former periods, 

we acquire a more perfect knowledge of its present condi- 

tion, and* more comprehensive views concerning the laws 

now governing its animate and inanimate productions. 

When we study history, we obtain a more profound in- 

sight into human nature, by instituting a comparison between 

the present and former states of society. We trace 

the long series of events which have gradually led to the 

actual posture of affairs, and by connecting effects with 

their causes, we are enabled to classify and retain in the 

memory a multitude of complicated relations, the various 

peculiarities of national character, the different degrees of 

moral and intellectual refinement, and numerous other cir- 

cumstances, which, without historical associations, would 

be uninteresting or imperfectly understood. When we 

carry back similar relations into the history of nature, we 

likewise investigate nature's operations in former epochs. 

The form of a coast, the configuration of the interior of 

a country, the existence and extent of lakes, valleys, and 

mountains, can often be traced to the former prevalence of 

earthquakes and volcanoes in regions which have long been 

undisturbed. To these remote convulsions the present fer- 

tility of some districts, the sterile character of others, the 

elevation of land above the sea, the climate, and various 

peculiarities, may be distinctly referred. Many distinguishing 

features of the surface of the earth may often be as- 

cribed to the operation, at a remote era, of slow and tran- 

quil causes, to the gradual deposition or sediment in a lake

16 INTRODUCTION. 

or in the ocean, or to the prolific 

increase of testacea and 

corals. "We also find in certain localities subterranean de- 

posits of coal, consisting of vegetable matter formerly 

drifted into seas and lakes. These seas and lakes have 

since been filled up, the lands whereon the forests grevt 

have disappeared or changed their form, the rivers and 

currents which floated the vegetable masses can no longer 

be traced, and the plants belonged to species which for ages 

have passed away from the surface of our planet, yet the 

commercial prosperity and numerical strength of a nation 

may now be mainly dependent on the local distribution of 

fuel determined By that ancient state of things. Geology 

is intimately connected to almost all physical sciences, as 

history is to the moral. An historian should, if possible, 

be profoundly acquainted with ethics, politics, jurispru- 

dence, the military art, theology, and with all branches of 

knowledge, by which an insight into human affairs, or into 

the moral and intellectual nature of man, can be obtained. 

No less desirable is it for a geologist to be well versed in 

chemistry, natural philosophy, mineralogy, zoology, com- 

parative anatomy, botany, and every science relating to 

organic and inorganic nature. Having such accomplishments, 

the historian and geologist would rarely fail to draw 

correct and philosophical conclusions from the various 

monuments transmitted to them from former occurrences. 

They would know to what combination of causes analogous 

effects were referable, and would often be enabled to supply 

by inference information concerning many events unrecorded 

in the defective archives of former ages. 

Mineralogy is sometimes understood as comprising the 

natural history of every portion of inorganic nature. Here

INTRODUCTION. 17 

we consider it as limited to the natural history of simple 

minerals, or mineral species. In the strictest sense, a min- 

eral species is a natural inorganic body, possessing a defi- 

nite chemical composition, and assuming a regular deter- 

minate form, or series of forms. Many substances heretofore 

regarded as minerals will naturally be excluded such 

as all the artificial salts, the inorganic secretions of plants 

and apimals, the remains of former living beings now im- 

bedded in rocks. Many substances originally organic pro 

ducts have by common consent found a place in mineral 

systems such as coal, amber, and -mineral resins which 

also some amorphous substances, 

ought not to be the case ; 

with no forms or chemical a*s composition, some kinds of 

clay, have also been introduced into works on Mineralogy, 

but often improperly, and with no beneficial result. Aggregates 

of simple minerals or rocks are likewise excluded from 

the science of Mineralogy, though the various associations 

of minerals, their modes of occurrence, and their geologi- 

cal position, are important points in the history of the dif- 

ferent species. One most important object in Mineralogy is 

a full description of minerals, their essential properties and 

distinctive characters, as will enable the student to distin- 

guish the various species, and to. recognize them when they 

occur in nature. 

The gems, or precious stones, are obtained from miner- 

als. It is indispensable, therefore, to be fully acquainted 

with all the characters which distinguish them from one 

another, which is accomplished by the terminology or no- 

menclature of the science of Mineralogy that is, with the 

meaning of the terms used in describing the properties of 

minerals, and the various modifications they may undergo,

18 

and also an account of the properties themselves. The 

system of classification is another closely related portion of 

Mineralogy. It gives an account of the order in which the 

mineral species are arranged. A third and most important 

part of Mineralogy is the physiography 

of the various 

species giving an account of their characteristic marks, 

and a description of their appearance or external aspect 

and forms, their principal physical and chemical properties, 

their mode of occurrence, with their geological and geo- 

graphical distribution, and their various uses, whether in 

nature or whether in tne arts, or as gems for ornamental 

purposes,

PART I. 

TERMINOLOGY. 

CHAPTER I. 

FORM OF MIXERAIS. 

THE physical properties of a mineral comprise all those 

properties belonging to it as a body existing in space, and 

consisting of matter aggregated in a peculiar way. The 

more important of these are, 

its form as shown in crystal- 

lization ; its structure as determining its mode of cleavage 

and fracture ; its hardness and tenacity ; its weight or spe- 

cific gravity ; 

magnetism. 

and its relations to light, heat, electricity, and 

Crystalline and Amorphous. Mineral substances occur 

'in two distinct modes of aggregation. Some consist of 

minute particles simply collected together, with no regularity 

of structure or constancy of External form, and are 

named amorphous. All fluid minerals are in this condition, 

together with some solid bodies, which appear to have condensed 

either from a gelatinous condition like opal, when 

they are named porodine, or from a state of igneoue fluidity 

like, obsidian and glass, when they are named hyalite. The 

other class have their ultimate atoms evidently arranged 

according to definite law, and are named crystallim., when 

the regulai ity of structure appears only in the internal *is-

20 A PRACTICAL TREATISE ON GEMS. 

position of the parts ; and crystallized, when it also produces 

a determinate external form, or a crystal. 

CRYSTALS. 

Faces, Edges, Angles, Axes of Crystals. The word 

crystal in mineralogy designates a solid body exhibiting an 

original (not artificial) more or less regular polyhedric form. 

It is thus bounded by plane surfaces, named faces, which 

intersect in straight lines OY. edges, and these again meet in 

. points and form solid angles, bounded by three or more 

faces. The space occupied by a crystal is often named a 

form of crystallization, which is thus the mathematical 

figure regarded as independent of the matter that fills it. 

Crystals bounded by equal and similar faces are named 

simple forms / while those in which the faces are not equal 

and similar are named compound forms, or combinations, 

being regarded as produced by the union or combination of 

two or more simple forms. The cube or hexahedron (fig. 

1), bounded by six equal and similar squares; 

the octahe- 

dron (fig. 2), by eight equilateral triangles ; and the rhom- 

bohedron, by six rhombs, are thus simple forms. An axis 

of a crystal is a line -passing through its centre and termi- 

nating either in the middle of two faces, or of two edges, or 

in two angles ; and axes terminating in similar parts of a 

crystal are named similar axes. In describing a crystal, one 

of its axes is supposed to be vertical or upright, and is then 

named the principal axis, and that axis is chosen which is 

the only one of its kind in the figure. A few other techni- 

cal terms used in describing crystals will be explained as 

they occur. . 

Systems of Crystallization. The forms of crystals that 

occur in nature seem almost innumerable. On examining 

them, however, more attentively, certain relations are dis- 

.

FORM OF MINERALS. 21 

covered even between highly complex crystals. When the 

axes are properly chosen, and placed in a right position, the 

various faces are observed to group themselves in a regular 

and beautiful manner around these axes, and to be all so 

related as to compose connected series produced according 

to definite laws. In every mineral species there is a certain 

form of crystal from which, as a primary, every other form 

of crystal observed in that mineral species may be deduced. 

In each species the axes, bearing to each other definite 

numerical proportions, intersect at angles which are constant. 

So also the faces of the various forms are related to each 

other, and to their primary, according to certain definite 

laws. When viewed in this manner, amd referred to their 

simplest forms, the innumerable variety of crystals occurring 

in nature may all be reduced to six distinct groups, or, as 

The following 

they are named, systems of crystallization. 

are the names given to these systems of crystallization in 

some of the best authors : 

Naumann. 

1. Tesseral System. 

2. Tetragonal System. 

8. Hexagonal System. 

4. Rhombic System." 

5. Monoclinohedric System. 

6. Triclinohedric System. 

In the following treatise the terminology of Naumann is 

adopted, his method of classifying and describing crystals 

appearing the simplest and best adapted to promote the 

progress of the student. 

Holohedric and Hemihedric. Before describing these 

systems, it must be observed that certain crystals appear as 

the half of others, and are therefore named hemihedric ; 

while the crystals with the full number of faces are named 

holohedric. Hemihedric crystals are formed when the alter-


nate faces or groups of faces of a holohedric crystal increase 

symmetrically, so as to obliterate the other faces. Thus, 

if four alternate faces of the octohedron increase so as to 

obliterate the other four, a tetrahedron with half the num- 

ber of faces is formed. 

I. The first, or Tesseral System, named from tessera, a 

cube, wliich is one of the most frequent varieties, is charac- 

terized by three equal axes intersecting each other at right 

angles. Properly speaking, this system has no chief axis, 

as any one of them may be so named, arid placed upright 

in drawing and describing the crystals. Of these there are 

thirteen varieties, which are thus classed and named from 

the number of their faces : 

1. One Tetrahedron, or form with four faces. 

2. One Hexahedron, with six faces. 

3. One Octahedron, with eight faces. 

4. Four Dodecahedrons, with twelve faces. 

5. Five Icosi tetrahedrons, with twenty-four faces. 

6.r One Tetracontaoctahedron, with forty-eight faces. 

The dodecahedrons are further distinguished, according 

to the form of their faces, into rhombic, trigonal, deltoid, 

and some of the icositetra- 

and pentagonal dodecahedrons ; 

hedrons have also received peculiar names. 

Fig.1. Fig. 2


The following is a description, with figures, of the differ- 

ent forms above mentioned, beginning with 

The Hololiedric forms. 

1. The hexahedron or cube (fig. 1) is bounded by sax 

equal squares, has twelve edges, formed by faces meeting 

at 90, and eight trigonal angles. The principal axes join 

the centre points of any two opposite faces. Examples are 

fluor spar, galena, boracite. 

2. The octahedron (fig. 2), bounded by eight equilateral 

triangles, has twelve equal edges, with planes meeting at 

109 28', and six tetragonal angles. 

* 

The principal axes 

join the opposite angles, two and two. Example, alum, 

spinel, magnetic iron ore. 

3. The rhombic-dodecahedron (fig. 3) is bounded by 

twelve equal and similar rhombs (diagonals as 1 andv^2), 

Fig.* Fig. 4. 

has twenty-four equal edges of 120, and six tetragonal and 

eight trigonal angles. The principal axes join two opposite 

tetragonal angles. Ex., garnet, boracite. 

4. The tetrakishexahedrons (variety of icositetrahedron, 

fig. 4) are bounded by twenty-four isosceles triangles, ar- 

ranged in six groups of four each. They have twelve longer 

edges which correspond to those of the primitive or in-


scribed tube, and twenty-four shorter edges placed over 

each of its faces. The angles are eight hexagonal and six 

tetragonal ; 

the latter joined two and two by the three prin- 

cipal axes. This form varies in general aspect, approach- 

on the other, to the rhom- 

ing, on the one hand, to the cube ; 

bic-dodecahedron. Ex., fluor spar, gold. 

5. The triakisoctahedrons (variety of icositetrahedron, 

fig. 5) are bounded by twenty-four isosceles triangles, in 

eight groups of three, and, like the previous form, vary in 

general aspect from the octahedron on one side, to the 

rhombic-dodecahedron on .the other. The edges are twelve 

longer, corresponding with those of the' inscribed octahedron, 

and twenty-four shorter, three and three over each 

of the faces. The angles are eight trigonal and six dite- 

tragonal (formed by eight faces) ; the latter angles joined 

two and two by the principal axes. Ex., galena, diamond. 

Fig. 5. Fig. 6. 

6. The icositetrahedrons (most common variety, fig. 6) 

with .four . 

are bounded by twenty-four deltoids or figures 

sides, of which two and two adjacent ones are equal. This 

form varies from the octahedron to the cube, sometimes 

approaching the former and sometimes the latter in general 

jispect. The edges are twenty-four longer and twentyfour 

shorter. The angles are six tetragonal joined by the


principal axes, eight trigonal, and twelve rhombic, or tetra- 

gonal with unequal angles. 

7. The hexakisoctahedrons (fig. 7), bounded by forty- 

eight scalene triangles, vary much in general aspect, approaching 

more or less to all the preceding forms ; but 

most frequently they have the face? arranged either in six 

groups of eight, or eight of six, or twelve of four faces. 

There are twenty-four long edges, often corresponding to 

those of the rhombic-dodecahedron ; twenty-four interme- 

diate edges lying in pairs over each edge of the inscribed 

octahedron ; 

and twenty-four short edges in pairs over the 

edges of the inscribed cube. There are six ditetragonal 

angles joined by the principal axes, eight hexagonal and 

twelve rhombic angles. Ex., fluor spar, garnet, diamond. 

Fig. 7. 

The seven forms of crystals now described are related to 

each other in the most intimate manner. This will appear 

more distinctly from the following account of the derivation 

of the forms, with which is conjoined an explanation of the 

crystallographic signs or symbols by which they are designated. 

We have adopted these symbols throughout this 

work, in the belief that they not only mark the forms in a 

greatly abbreviated manner, but also exhibit the relations 

of the forms and combinations in a way which words could 

hardly accomplish.

26 A PRACTICAL TREATISE OX GEMS. 

The derivation of forms is -that process by which, from 

one form chosen for the purpose, and considered as the 

type the fundamental or primary form all the other 

forms of a system may be produced, according to fixed prin- 

ciples or general laws. In order to understand this process 

or method of derivation, the student should keep in mind 

that the position of any plane is fixed when the positions 

of any three points in it, not all in one straight line, are 

known. To determine the position, therefore, of the face 

of a crystal, it is only necessary to know the distance of 

three points in it from the centre of the crystal, or the 

points in which the face or its supposed extension would intersect 

the three axes of the crystal. The portion of the 

axes between this point and the centre are named parameters, 

and the position of the face is sufficiently known when 

the relative length or proportion of these parameters is 

ascertained. When the position of one face of a simple 

form is thus fixed or described, all the other faces are in 

like manner fixed, since they are all equal and similar, and 

all intersect the axes in a uniform manner ; and the expression 

which marks or describes one face, marks and describes 

the whole figure. 

The octahedron is generally adopted as the primary or 

fundamental form of the tessera! system, and distinguished 

by the first letter of the name, O. Its faces cut the half 

axes at equal distances from the centre ; so that these semi- 

axes, or the parameters of the faces, have to each other the 

proportion 1:1:1. In order to derive the other forms 

from the octahedron, the following construction is em- 

ployed. The numbers refer to the descriptions above. 

Suppose a plane so placed in each angle of the octahedron 

as to be vertical to the axis passing through that 

angle and consequently parallel to the two other axes (or 

to cut them at an infinite distance = 00); then the hexa-


hedron or cube (l) 

is produced, designated by the crystal- 

of the 

lographic sign oo O oo ; expressing the proportion 

parameters of its faces, or oo : oo : 1. If a plane is sup- 

posed placed in each edge parallel to one axis, and cut- 

ting the two other axes at equal distances, the resulting 

figure is the rhombic dodecahedron (3), designated by the 

sign oo O, the proportion of the parameters of its faces be- 

arises when on 

ing oo : 1 : 1. The triakisoctahedron (5) 

each edge of the octahedron planes are placed cutting the 

axis not belonging to that edge at a distance from the centre 

m which is a rational number greater than 1. The 

is therefore mil 1, and its 

proportion of its : parameters 

sign mO ; 

the most common varieties being fO, 2O, and 

3O. When, on the other hand, from a similar distance m 

in each two semiaxes prolonged, a plane is drawn to the 

other semiaxis, or to each angle, an ikositetrahedron (6) is 

formed the ; parameters of its faces 

proportion m : 1 : m, and its sign is 

have consequently the 

mOm the most common 

varieties being 2O2 and 303, the former very frequent 

in leucite, analcime, and garnet. When, again, planes are 

drawn from each angle, or the end of one semiaxis of the 

octahedron, parallel to a second axis, and cutting the third 

at a distance rc, greater than 1, then the tetrakishexahedron 

(4) is formed, the parameter of its faces oo : 1 : n ; its sign 

3>On; and the most common varieties in nature ooOf, 

oc O2, and oo O3. Finally, if in each semiaxis of the octahedron 

two distances, m and ft, be taken, each greater than 

1, and m also greater than n, and planes be drawn from 

each angle to these points, so that the two planes lying 

over each edge cut the second semiaxis belonging to that 

edge, at the smaller distance n, and the third axis at the 

greater distance m, then the hexakisoctahedron (7) is produced, 

the parameters of which are m : n : 1, its sign mOn, 

and the most common varieties 3Of, 4O2, and 5Of .


The next class of crystals are the semi-tesseral form,s; and 

first, those with oblique faces, often named tetrahedral, from 

their relation to the tetrahedron. (1.) This form (fig. 8) 

Fig. 8. 

Fig. 9. 

is bounded by four equilateral triangles, has six equal edges 

with faces meeting at 70 32 ', and four trigonal angles. 

The principal axes join the middle points of each two op- 

posite edges. Ex., gray-copper ore, boracite, and helvine. 

(2.) The trigonal dodecahedrons (fig. 9) are bounded by 

twelve isosceles triangles, and vary in general form from 

the tetrahedron to the hexahedron. There are six longer 

edges corresponding to those of the inscribed tetrahedron, 

and twelve shorter placed three and three over each of its 

faces ; and four hexagonal and four trigonal angles. Ex., 

gray-copper ore, and bismuth-blende. (3.) The deltoiddodecahedrons 

(fig. 10) are bounded by twelve deltoids, 

and vary in general form from the tetrahedron on the one 

hand, to the rhombic-dodecahedron on the other. They 

have twelve longer edges lying in pairs over the edges of 

the inscribed tetrahedron ; 

and twelve shorter edges, three 

and three over each of its faces. The angles are six tetra- 

gonal (rhombic), four acute trigonal, 

and four obtuse tri- 

gonal angles. The principal axes join two and two opposite 

rhombic angles. Ex., gray-copper ore. (4.) The hex- 

akistetrahedrons (fig. 11) are bounded by twenty-four


scalene triangles, and most commonly have their faces 

grouped in four systems of six each. The edges are twelve 

shorter and twelve longer, lying in groups of three over 

Fig. 10. Fig. 11. 

each face of the inscribed tetrahedron, and twelve interme 

diate in pairs over its edges. The angles are six rhombic, 

joined in pairs by the principal axes, and four acuter and 

four obtuser hexagonal angles. Ex., diamond. 

The derivation and signs of these forms are as follows : 

The tetrahedron arises when four alternate faces of the 

octahedron are enlarged, so as to obliterate the other four, 

and its sign is hence . But, as either four faces may be 

thus enlarged or obliterated, two tetrahedrons can be formed 

similar in all respects except in position, and together mak- 

ing up the octahedron. These are distinguished by the 

signs + and , added to the above symbol, but only the 

latter in general expressed thus . In ah 1 

hemihedric 

systems two forms similarly related occur, which may thus 

be named complementary forms. The trigonal dodecahe- 

dron is derived from the icositetrahedron, by the expansion 

of the alternate trigonal groups of faces. Its sign is - 

,


2O2 

the most common variety being , found in gray-copper 

ore. The deltoid-dodecahedron is in like manner the result 

of the increase of the alternate trigonal groups of faces of the 

triakisoctahedron, and its sign is . Lastly, 

the hexakis- 

tetrahedron arises in the development of alternate hexa- 

gonal groups of faces in the hexakisoctahedron, and its sign 

. 

mOn ~' 

The parallel-faced semitesseral forms are two. (1.) The 

pentagonal dodecahedrons (fig. 12) are bounded by twelve 

Fig. 12. Fig. 13. 

symmetrical pentagons, and vary in general aspect between 

the hexahedron and rhombic-dodecahedron. They 

have six regular (and in general longer) edges, lying 

over the faces of the inscribed hexahedron, and twenty- 

four generally shorter (seldom longer) edges, usually lying 

in pairs over its edges. The angles are eight of three equal 

angles, and twelve of three unequal angles. Each princi- 

pal axis unites two opposite regular edges. This form is 

derived from the tetrakishexahedron, and its sign is , 

one of the most common varieties being , found fre- 

quently in iron pyrites and cobaltine. (2.) The dyakisdo-


decahedron (fig. 13), bounded by twenty-four trapezoids 

with two sides equal, has twelve short, twelve long, and 

twenty-four intermediate edges. The angles are six equi- 

angular rhombic, united in pairs by the principal axes, eight 

trigonal, and twenty-four irregular tetragonal angles. 

derived from the hexakisoctahedron, and its sign is F ' 

It is 

the brackets being used to distinguish it from the hexakiste- 

Fig. 14. Fig. 15. 

trahedron, also derived from the same primary form. It 

occurs in iron pyrites and cobaltine. There are two other 

tetrahedral forms, the pentagonal dodecahedron (fig. 14), 

and the pentagonal icositetrahedron (fig. 15), both bounded 

by irregular pentagons, but not yet observed in nature. 

Combinations. These forms of the tesseral system (and 

this is true also of the five other systems of crystallization) 

not only occur singly, but often two, three, or more are united 

in the same crystal, forming what are named combinations. 

In this case it is evident that no one of the individual forms 

can be completely developed, because the faces of one form 

must partially interfere with the faces of the other forms. 

A combination therefore implies that the faces of one form 

shall appear symmetrically disposed between the faces of 

other forms, and consequently in the room of certain of 

their edges and angles. 

, J 

These edges and angles are thus,


as it were, cut off, and new ones produced in their place, 

which properly belong neither to the one form nor the other, 

but are edges or angles of combination. Usually, one form 

predominates more than the others, or has more influence on 

the general aspect of the crystal, and hence is distinguished 

as the predominant form, the others being named subordi- 

nate. The following terms used on this subject require ex- 

planation. A combination is developed when all the forms 

contributing to its formation are pointed out ; and its sign 

consists of the signs of these forms, written in the order oi 

their influence on the combination, with a point between. 

An angle or edge is said to be replaced when it is cut ofl 

by one or more secondary planes ; 

by one plane, forming equal angles with the adjacent faces ; 

and an edge is bevelled when replaced by two planes, which 

are equally inclined to the adjacent faces. 

it is truncated when cut 

It will be readily seen that such combinations may be 

exceedingly numerous, or rather infinite ; 

and only a few 

of the more common can be noticed, simply as specimens 

of the class. Many others more complicated will occur in 

the descriptive part of this treatise. Among plenotesseral 

combinations, the cube, octahedron, and also the rhombicdodecahedron, 

are the predominant forms. In fig. 16 the 

Fig. 16. Fig. 17. 

cube has its angles replaced by the faces of the octahedron, 

and the sign of this combination is ooOoo . O. In fig. 17 

this process may be regarded as having proceeded still fur-


ther, so that the faces of the octahedron now predominate, 

and the sign, of the same two elements but in reverse order, 

is O . ooOoo. In fig. 18 the cube has its edgesre placed 

Fig. la Fig. 19. 

by the faces of the rhombic-dodecahedron, the sign being 

oo Goo . ccO; while in fig. 19 there is the same combina- 

tion, but with the faces of the cube subordinate, and hence 

the symbol is ooO . ooOoo . The former figure, it will be 

seen, has more the general aspect of the cube ; 

the dodecahedron. 

the latter of 

In combinations of semitesseral forms with oblique faces, 

the tetahedron, the rhombic-dodecahedron, or even the 

hexahedron, seldomer a trigonal-dodecahedron, are the more 

Fig. 20. Fig. 2L 

common predominant forms. In fig. 

20 two tetrahedrons 

in opposite positions, -^ are combined. In 21 a 

fig. 

2*


very complex combination of seven forms is represented in 

a crystal of gray-copper ore, its full sign being 

(0 .ooOcc (/) . ^ 

(o). 

the letters in brackets connecting them with the respective 

faces of the figure. As examples of combinations of semitesseral 

forms with parallel faces, we may take fig. 22, in 

Fig. 22. Fig. 23. 

which each of the angles of the cube is unsymmetrically 

replaced by three faces of the dyakisdodecahedron, and 

hence ccOoo . I I ; or fig. 23, in which the pentagonal- 

dodecahedron has its trigonal angles replaced by the faces 

oo02 

of the octahedron, consequently with the sign . O. 

Figure 24 represents the same combination 

but with greater predomi- 

nance of the faces of the octahedron, 

the crystal being bounded by eight 

equilateral 

angles. 

and twelve isosceles tri- 

II. Tetragonal System. This system 

has three axes at right angles, 

Fig. 24. 

two of them equal and one unequal. The last is the principal 

axis, and when it is brought into a vertical position the 

crystal is said to be placed upright. Its ends are named


poles, and the edges connected with them polar edges. The 

two other axes are named subordinate or lateral axes, and 

a plane passing through them is named the basis of the 

crystal. The two planes that pass through the principal 

and one of the lateral axes are named normal chief sections, 

and a plane through the chief axis intermediate to them, a 

diagonal chief section. The name tetragonal 

from the form of the basis, which is usually quadratic. 

is derived 

There are eight tetragonal forms, of which five are closed, 

that is, bounded on ah 1 

sides by planes, and of definite 

extent, and three open, which in certain directions are not 

bounded, and consequently of indefinite extent. 

The description of the varieties is as follows, it being 

premised that a crystallographic pyramid is equivalent to 

two geometrical pyramids joined base to base. 

Fig. 25. Fig. 26. 

Closed forms. (1.) Tetragonal pyramids (figs. 25, 26) are 

inclosed by eight isosceles triangles, with four middle edges 

all in one plane, and eight polar edges. There are three 

kinds of this form, distinguished by the position of the lat- 

eral axes. In the first these axes unite the opposite angles ; 

in the second they intersect the middle edges equally;

C A PRACTICAL TREATISE ON GEMS. 

and in the third they lie in an intermediate position, or 

divide these edges unequally ; 

the latter being hemihedral 

forms. These pyramids are also distinguished as obtuse 

(fig. 25) or acute (fig. 26), according as the vertical angle 

is greater or less than in the octahedron, which, though 

intermediate, is never a tetragonal form. (2.) Ditetragonal 

pyramids (fig. 27) are bounded by sixteen scalene triangles, 

Fig. 27. Fig. 28. 

whose base lines are all in one plane. This form rarely 

occurs except in combinations. (3.) Tetragonal sphenoids 

(fig. 28), bounded by four isosceles triangles, are the hemihedral 

forms of the first variety of tetragonal pyramids. 

(4.) The tetragonal scalenohedron (fig. 29), bounded by 

eight scalene triangles, whose bases rise and fall in a zig-zag 

line, is the hemihedral form of the ditetragonal pyramid. 

The latter two forms are rare. 

Open forms. Tetragonal prisms (fig. 30) bounded by 

four planes parallel to the principal axis; ditetragonal 

prisms by eight similar planes. In these prisms the prin- 

or to be 

cipal axis is supposed to be prolonged infinitely, 

unbounded. Where it is very short and the lateral axes


infinite, the basal piriacoid is formed, consisting merely ot 

two parallel faces. 

The various series of tetragonal crystals are distinguished 

from each other only by their relative dimensions. To 

Fig. 29. Fig. 80. 

determine these, one of the series must be chosen as the 

fundamental form, and for this purpose a tetragonal pyramid 

of the first variety, designated by P as its sign, is selected. 

The angle of one of its edges, especially the middle edge, 

found by measurement, determines its angular dimensions ; 

while the proportion of the principal axis (a) to the lateral 

axes supposed equal to 1, gives its linear dimensions. The 

parameters, therefore, of each face of the fundamental form 

are 1 : 1 : a. 

Now if m be any (rational) number, either less or greater 

than 1, and if from any distance ma in the principal axis 

planes be drawn to the middle edge of P, then new tetra- 

gonal pyramids of the first kind, but more or less acute or 

obtuse than P, are formed. The general sign of these 

pyramids is mP, and the most common varieties ^P, 2P, 

3P ; with the chief axis equal to ^, twice or thrice that of 

P. If m becomes infinite, or = o>, then the pyramid passes 

into a prism, indefinitely extended along the principal axis,

A PBACTICAL TREATISE ON GEMS. 

and with the sign ooP; if m=0, which is the case when 

the lateral axes are supposed infinite, then it becomes a 

pinacoid, consisting properly of two basal faces, open towards 

the lateral axes, and designated by the sign OP. The 

ditetragonal pyramids are produced by taking in each lateral 

axis distances n greater than 1, and drawing two planes to 

these points from each of the intermediate polar edges. 

The parameters of these planes are therefore m : I : n, and 

the general sign of the form mPn, the most common values 

of n being J, 2, 3, and oo. When n = oo, a tetragonal 

pyramid of the second kind arises, designated generally by 

mP oo, the most common in the mineral kingdom being P oo 

and 2P oo. The relation of these to pyramids of the first 

Fig. 81. 

Fig. 32. 

kind is shown in fig. 31, where ABBBX is the first, and 

ACCCX the second kind of pyramid. In like manner from 

the prism ooP, the ditetragonal prisms ooPn are derived, 

arid finally when n = oo, the tetragonal prism of the sec- 

ond kind, whose sign is oopoo . 

The combinations of the tetragonal system are either 

holohedric or hemihedric ; but the latter are rare. Prisms 

and pinacoids must always be terminated on the open sides 

by other forms. Thus in fig. 32 a square prism of the first 

kind is terminated by the primary pyramid, and has its


lateral angles again replaced by another more acute pyra- 

. 2Poo. 

mid of the second kind, so that its P sign is ooP . 

In fig. 33 a prism of the second kind is first bounded by 

Fig. 33. Fig. 84. 

the fundamental pyramid, and then has its edges of combi- 

nation replaced by a ditetragonal 

pyramid, and its sign is here 

ooPoo . P 

. 

3P3. In fig. 34 the 

polar edges of the pyramid are 

replaced by another pyramid, its 

sign being P. Poo . In fig. 

35 a 

hemihedric form very characteris- 

tic of copper pyrites is represented, 

P and P' being the two sphenoids, 

Fi s- ;35- 

a the basal pinacoid, and 5, c, two ditetragonl pyramids. 

III. The Hexagonal System. The essential character of 

this system is, that it has four axes, three equal lateral axes 

intersecting each other in one plane at 60, and one principal 

axis at right angles to them. The extremities of the principal 

axis are named poles, and sections through it and one 

lateral axis, normal chief sections. The plane through the 

lateral axes is the basis, and from its hexagonal form gives 

the name to the system. As in the last system, its forms 

are either closed or open / and are divided into holohedral,


hemihedral, and tetartohedral, the last forms with only a 

fourth part of their faces developed. The tetartohedral and 

many of the hemihedral forms are of rare occurrence, and 

only a few of the more common require to be here described. 

The hexagonal pyramids (figs. 36, 37) are bounded by 

twelve isosceles triangles, and are of three kinds, according 

Fig. 36. Fig. 37. 

as the lateral axes fall in the angles, in the middle of the 

lateral edges, or in another point of these edges, the latter 

being hemihedral forms. They are also classed as acute 

or obtuse, but without any very precise limits. The trigonal 

pyramid is bounded by six triangles, and may be viewed 

as the hemihedral form of the hexagonal. The dihexago- 

nal pyramid is bounded by twenty-four scalene triangles, 

but has never been observed alone, and rarely even in com- 

binations. The more common prisms are the hexagonal of 

six sides, and the dihexagonal of twelve sides. 

As the fundamental form of this system, a particular pyramid 

P is chosen, and its dimensions determined either 

from the proportion of the lateral to the principal axis 

From this 

(1 : a), or from the measurement of its angles. 

form (mP) others are derived exactly as in the tetragonal

POKM OF MINERALS. 41 

system. Thus dihexagonal pyramids are produced with 

the general sign wPn, the chief peculiarity being that, 

whereas in the tetragonal system n might have any rational 

value from 1 to oo, in the hexagonal system it can only 

vary from 1 to 2, in consequence of the geometric charac- 

ter of the figure. When n=2 the dihexagonal changes 

into an hexagonal pyramid of the second kind, whose sign 

is raP2. When m is = oo various prisms arise from similar 

changes in the value of n ; 

and when w=0, the basal pina- 

coid. 

Few hexagonal mineral species form perfect holohedric 

combinations. Though quartz and apatite appear as such, 

Fig. 33. Fig. 39. 

yet properly the former is a tetartohedral, the latter a hemihedral 

species. In holohedric species the predominant 

faces are usually those of the two hexagonal prisms ooP 

and oo P2, or of the pinacoid OP; while the pyramids P 

and 2P2 are the most common subordinate forms. Figure 

38 represents the prism, bounded on the extremities by two 

pyramids ; one, P, forming the point, the other 2P2, the 

rhombic faces on the angles, or ocP . P . 2P2. In some 

crystals the lateral edges of the prism are replaced by the


second prism o>P2, producing an equiangular twelve-sided 

prism, which always represents the combination ooP. ooP2, 

and cannot occur as a simple form. An example of a more 

complicated combination is seen in fig. 39, of a crystal 

of apatite, whose sign with the corresponding letters is 

ooP2(e) . OP(P) . $P(r) . P() 

. 2P(z) . P2() . 

Hexagonal minerals more frequently crystallize in those 

series of hemihedral forms that are named rhombohedral, 

from the prevalence in them of rhombohedrons. These 

are bounded by six rhombs (fig. 40), whose lateral edges do 

Fig 40. 

not lie in one plane, but vise and fall in a zig-zag manner. 

The principal axis unites the two trigonal angles, formed by 

three equal plane angles, and in the most common variety 

the secondary axes join the middle points of two opposite 

edges. When the polar edges form an angle of more than 

90, the rhombohedrons are named obtuse ; when of less, 

are bounded 

acute. Hexagonal scalenohedrons (fig. 41) 

do not lie 

by twelve scalene triangles, whose lateral edges 

in one plane. The principal axis joins the two hexagonal 

angles, and the secondary axes the middle points of two 

opposite lateral edges. 

The rhombohedron is derived from the first kind of 

hexagonal pyramid by the hemihedric development 

of its 

alternate faces. Its general sign should therefore be ; 

2


but on several grounds it is found better to designate it by 

R or raR, and its complimentary figure by niR. When 

the prism or pinacoid arise as its limiting forms, they are 

designated by ooR and OR, though in no respect changed 

from the limiting forms 00 P and OP of the pyramid. The 

scalenohedron is properly the hemihedric form of the 

but is better derived from the 

dihexagonal pyramid, 

inscribed rhombohedron mR. If the halves of the prin- 

cipal axis of this are multiplied by a definite number n^ 

Fig. 41. 

and then planes drawn from the extremities of this enlarged 

axis to the lateral edges of the rhombohedron, as in figure 

42, the scalenohedron is constructed. Hence it is designated 

by wiR", the n being written on the right hand, like 

an algebraic exponent : and the dihexagonal prism is in 

like manner designated by ooR".


The combinations of rhombohedric forms are very nu- 

merous, some hundreds being described in calc-spar alone. 

Among the more common is the prism in combination with 

a rhombohedron, as in the twin crystal of calc-spar (fig. 43), 

Fig. 48. Fig. 44. 

with the sign coR. iR, the lower half being 

the same 

form with the upper, but turned round 180. In figure 

44, the rhombohedron mR has its polar edges replaced by 

Fig. 45. Fig. 46. 

another rhombohedron JwR ; and in figure 

45 its lateral 

edges bevelled by the scalenohedron mR*. A more com-


plex combination of five forms is represented in the crystal 

of calc-spar, fig. 46, its sign with the letters on the faces 

being R 5 

(y) . R 

3 

(r) . R(P) . 4R(m) . oo R(c). Tetartohedric 

combinations are seen most distinctly in pure quartz or rock- 

crystal, the pyramids of the first kind appearing as rhom- 

bohedrons, those of the second kind as trigonal pyramids, 

the dihexahedral prisms as ditrigonal prisms, and the prism 

oo P2 as a trigonal prism. Most of these forms, however, 

in the combinations 

occupy but a very subordinate place 

which consist essentially of the prism ooP, and the rhomp 

bohedron R . 

IV. Rhombic System. The rhombic system is charac- 

terized by three axes, all unequal, but at right angles to 

each other. One of these is assumed as the chief axis, 

when the others are named subordinate. The plane passing 

through the secondary axes, or the basis, forms a 

rhomb, and from this the name is derived. This system 

comprises only a few varieties of forms that are essentially 

distinct, and its relations are consequently very simple. 

Fig. 47. Fig. 43. 

The closed forms are, (1st.) The rhombic pyramids 

(figs. 47, 48), bounded by eight scalene triangles, whose

46 A POPULAR TKEATISE ON GEMS. 

lateral edges lie in one plane, and form a rhomb. They 

have eight polar edges, four acute and four more obtuse. 

and four lateral edges, and six rhombic angles, the most 

acute at the extremities of the longest axis. (2cl) The 

rhombic sphenoids (fig. 49) 

are bounded by four scalene 

triangles with their lateral 

edges not in one plane ; 

and are a hemihedric form 

of the rhombic pyramid of 

unfrequent occurrence. The 

open forms again are, (3d.) 

Rhombic prisms bounded 

by four planes parallel to Fig. 49. 

one of the axes which is 

indefinitely extended. They are divided into upright and 

horizontal prisms, according as either the principal or one of 

the lateral axes is supposed to become infinite. For the 

latter form the name doma or dome has been used ; 

and 

two kinds, the macrodome and the brachydome, have been 

distinguished. Rhombic pinacoids also arise when one axis 

becomes =0, and the two others are indefinitely extended. 

In deriving these forms from a primary, a particular 

rhombic pyramid P is chosen, and its dimensions determined 

either from the angular measurement of two of its edges, 

or by the linear proportion of its axes a : b: c\ the greater 

lateral axis b being assumed equal to 1. To the greater 

lateral axis the name macrodiagonal is frequently given ; 

to the shorter, that of brachydiagonal ; and the two principal 

sections are in like manner named macrodiagonal and 

brachydiagonal, according to the axis they intersect. The 

same terms are applied throughout all the derived forms, 

where they consequently mark only the position 

of the 

faces in respect to the axes of the fundamental crystal,


without reference to the relative magnitude of the derived 

axes. 

By multiplying the principal axis by any rational number 

m, greater or less than 1, a series of pyramids arise, 

whose general sign is mP, and their limits the prism and 

pinacoid, the whole series being contained in this formula, 

OP rnP P - mP ooP ; which is 

the fundamental series, the lateral axes always remaining 

From 

unchanged. 

each member a new 

series may, however, 

be developed in two 

directions by increas- 

ing one or other 

of the lateral axes. 

When the macrodia- 

gonal is thus multiplied 

by any number 

n greater than 1, and 

planes drawn from 

the distance n to the 

polar edges, a new 

pyramid is produced, 

named a macropyra- 

mid, with the sign 

wP/i, the mark over 

the P pointing out 

the axis enlarged. 

When M=QO a macrodome 

results,with 

Fig. 50. 

Fig. 51. 

the sign mPoo . If the shorter axis is multiplied, then bra- 

chypyramids and brachydomes are produced with the signs 

?nPn and mPcc . So also from the prism ooP, on the one 

side, numerous macroprisms ooP^, with the limiting ma-

48 A POPULAR TREATISE 05* GEMS. 

cropinacoid coPoo; on the other, numerous brachyprisma 

ooPft,, with the limit form ooPoo, or the brachypinacoid. 

In figs. 50, 51, the two domes are shown in their relation 

to the primitive pyramid. 

The pyramids seldom occur independent, or even as the 

predominant forms in a combination, sulphur, however, 

being an exception. Prisms or pinacoids usually give the 

general character to the crystal, which then appears either 

in a columnar or tabular, or even in a rectangular pyramidal 

form. The determination of the position of these crystals, 

Fig. 52. Fig. 54. 

as vertical or horizontal, depends on the choice of the chief 

axis of the fundamental form. In the topaz crystal (fig. 52) 

the brachyprism and the pyramid are the predominant ele- 

ments, associated with the prism, its sign and letters being 

53 of stilbite is another ex- 

ooP2(Q . P(o) . ooP(m). Fig. 

combined with 

ample, the macropinacoid co Poo or M, being 

the pyramid P(?"), the brachypinacoid ooPoo (T), and the 

basal pinacoid OP (P). Another instance is fig. 54 of a 

lievrite crystal, where the brachyprism and pyramid com- 

bine with the macrodome, P 

or coP2 . . Poo . The follow- 

ing figures are very common forms of barytes ; figs. 55 and


56 being both composed of the pinacoid, a brachydome, and 

macrodome, with sign OP 

(c).Poo(/)iPoo(d),the 

variation in aspect arising 

from the predominance of 

different faces ; 

consisting 

and fig. 57 

of the macro- 

dome -|P oo , the prism 

a>P(^), and the pinacoid 

OP. 

V. The Monodinohe- 

dric System. This system 

is characterized by three 

unequal axes, two of which 

intersect each other at an 

Fig. 55. 

Fig. 53. 

oblique angle, and are cut 

by the third at right angles. 

One of the Fig. 

oblique 

axes is chosen as the chief axis, and the other axes are then 

57. 

distinguished as the orthodiagonal (right-angled) and clinodiagonal 

(oblique-angled). The same terms are applied to 

the chief sections, and the name of the system refers to the 

fact that these two planes and the base, together with two 

right angles, form also one oblique angle C. 

The forms of this system approach very near to those of 

the rhombic series, but the inclination of the axes, even 

when almost a right angle, gives them a peculiar character, 

by which they are always readily distinguished. Each 

pyramid thus separates into two altogether independent 

forms or hemipyramids. Three varieties of prism also oc- 

cur, vertical, inclined, and horizontal, with faces parallel 

to the chief axis, the clinodiagonal or the orthodiagonal. 

The horizontal prisms, like the pyramids, separate into two 

independent partial forms, named hemiprisms or hemi- 

3

50 A POPULAR TREATISE ON GEMS. 

domes. The inclined prisms are often designated clino- 

domes, the term prism being restricted to the vertical 

forms. Orthopinacoids and clinopinacoids 

are also distinguished 

from their position in relation to the axes. 

The monoclinohedric pyramids (fig. 58) are bounded by 

A eight scalene triangles of two 

kinds, four and four only be- 

ing similar. Their lateral 

& 

edges lie all in one plane, 

and the similar triangles are 

placed in pairs on the clinodiagonal 

polar edges. The 

two pairs 

in the acute angle 

between the orthodiagonal 

and basal section are desig- 

nated the positive hemipyra- 

while the two pairs in 

mid ; 

the obtuse angles of the same 

sections form together the negative hemipyramid. But as 

these hemipyramids are wholly independent of each other, 

they are rarely observed combined. More frequently each 

occurs alone, and then forms a prism-like figure, with faces 

parallel to the polar edges, and open at the extremities. 

Hence, like all prisms, they can only appear in combination 

with other forms. The vertical prisms are bounded by 

four equal faces parallel to the principal axis, and the cross 

section is a rhomb ; the clinodomes have a similar form 

and section ; while the horizontal prisms or domes have 

unequal faces, and their section is a rhomboid. 

The mode of derivation of these forms closely resembles 

that of the rhombic series. A complete pyramid is assumed 

as the fundamental form, and designated =b P, in 

order to express the two portions of which it consists. Its 

dimensioRS a.re given when the proportion of its axes $;: c,


and the angular inclination of the oblique axes (7, which is 

also that of the orthodiagonal section to the basis, are 

known. 

dbwP 

The fundamental series 

P mP 

of forms is OP 

ooP from each of 

; 

whose members, by changing the dimensions of the other 

axes, new forms may be again derived. Thus from mP, 

by multiplying the orthodiagonal by any number n, a series 

of orthopyramids rtraP/*, is produced with the orthodomes 

raPoo , as limiting forms. The clinodiagonal produces a 

similar series, distinguished from the former by the sign 

being put in brackets, thus, db(wPw), with the limiting 

clinodome ( mP ) always completely formed, and therefore 

without the signs attached. From o>P arise ortho- 

prisms oo Ptt, and the orthopinacoid ooPoo; and clino- 

prisms (ooPtt), and the clinopinacoid (ooPoo). 

The combinations of this system may be easily under- 

stood from their resemblance to those of the rhombic ; 

the 

chief difficulty being in the occurrence of partial forms, 

which, however, closely resemble the hemihedric forms of 

the previous systems. We shall therefore only select a few 

examples frequently observed in the mineral kingdom. 

Fig. 59 represents a very common form of gypsum crystals 

Fig. 59. Fig. 60. 

(ooPoo) (P) . ooP(/) . P(&). 

The most common form of 

augite is represented in fig. 60, with the sign ct>P(m) .


oo Poo (r) . ( ooPoo ) (I) . P(s). Fig. 61 is a crystal of com 

mon felspar or orthoclase, composed of the clinopinacoid 

(ooPoo) (Jf), the prism ooP(f T 

), the basal pinacoid OP 

(P), and the hemidomes 2P (y) : to which, in fig. 

Fig. 61. Fig. 62. 

62 of 

the same mineral, the hemipyramid P(o), and the clinodome 

( 2Poo ) (rc), are added. 

VI. Tridinohedric System. This is the least regular of 

all the systems, and departs the most widely from symmetry 

of form. The axes are all unequal, and inclined at angles 

none of which are right angles, so that to determine any 

crystal or series of forms the proportion of the axes a : b : c, 

and also their angles, or those of the inclination of the chief 

sections, must be known. As in the previous system, one 

axis is chosen as the principal axis, and the two others dis- 

tinguished as the macrodiagonal and brachydiagonal axes. 

In consequence of the oblique position of the principal sec- 

tions, this system consists entirely of partial forms wholly 

independent on each other, and each composed only of two 

parallel faces. The complete pyramid is thus broken up 

into four distinct quarter pyramids, and the prism into two 

hemiprisms. Each of these partial forms is thus nothing 

more than a pair of parallel planes, and the various forms 

mere individual faces. This circumstance 

consequently


renders many triclinohedric crystals very unsymmetrical in 

appearance. 

Triclinohedric pyramids (fig. 63) 

are bounded by eight triangles, whose 

lateral edges lie in one plane. They 

are equal and parallel two and two 

to each other ; 

each pair forming, as 

just stated, a tetartopyramid or open 

form, only limited by combination 

with other forms, or, as we may suppose, 

by the chief sections. The 

prisms are again either vertical or in- 

the latter named domes, and 

clined ; 

their section is always rhomboidal. In deriving the forms, 

the fundamental pyramid is placed upright with its brachy- 

diagonal axis to the spectator, and the .partial forms desig- 

nated, the two upper by 'P and P', the two lower by ,P 

The further derivation now follows 

and P y , as hi the figure. 

Fig. 63. 

as in the rhombic system, with the modifications already 

mentioned, so that we need not delay on it longer, especially 

as the minerals crystallizing in these forms are not numerous. 

Fig. 64 

Some combinations of this system, as the series exhibited 

by most of the felspars, approach very near to the mono- 

clinohedric system ; while others, as the blue copper, 01

A POPULAR TREATISE ON GEMS. 

vitiiol, and axinite, show great incompleteness and want of 

symmetry. In the latter case the determination of the 

forms is often difficult and requires great attention. As 

specimens, we may notice the albite crystal (fig. 64), in 

which P is the basal piuacoid OP; J/the brachydiagonal 

pinacoid ooPco; s the upper right pyramid P'; Zthe right 

hemiprism ooP'; T the left hemiprism oo'P; and x the 

hemidome 'P'oo . Figures 65 and 66 are crystals of axinite, 

Fig. 65. Fig. 6G. 

the former from Dauphine, the latter very common in Corn- 

wall, of whose faces the following is the : development r 

the macropinacoid ooPoo ; P 

the left upper quarter pyramid 'P ; 

pyramid 2'P; s the left upper partial 

pyramid 3'P3 ; 

the left hemiprism co'P; u 

and x the hemidome 2'P,oo . 

Imperfections of Crystals. 

I the left upper quarter 

form of the macro- 

In the foregoing description of the forms of crystals the 

planes have been supposed smooth and even, the faces 

equal and uniform, or at the same distance from the centre 

or point of intersection of the axes, and each crystal also 

perfect or fully formed and complete on every side. In 

nature, however, these conditions are rarely if ever realized, 

and the edges of crystals are seldom straight lines, or 

the faces mathematical plane surfaces. A very interesting 

variety of these irregularities, which pervades all the systems 

except the tesseral, is named hemimorphism. In this

FORM OP MIXEEALS. 55 

the crystals are bounded on the opposite ends of their chiet 

axis by faces belonging to distinct forms, and hence only 

the upper or under half of each form is produced, or the 

crystal, as the name implies, is half-formed. Figure 67 represents 

a common variety of tourmaline, bounded on the 

Fig. 67. Fig. 63. 

upper end by the planes of the rhombohedrons R and 2R, 

and on the lower end by the basal piuacoid. In fig. 68 of 

electric calamine the upper extremity shows the basis &, 

two brachydomes o and p, and two macrodomes m and l\ 

while on the lower end it is bounded by ;the faces P of the 

primary form. This appearance becomes more interesting 

from the fact that most hemimorphic crystals acquire polar 

electricity from heat, that is, exhibit opposite kinds of 

electricity at opposite ends of the crystal. 

The faces of crystals are very frequently rendered im- 

perfect by striae, or minute linear and parallel elevations 

and depressions. These arise in the oscillatory combination 

of two crystal forms, alternately prevailing through small 

spaces. The striae, therefore, are in reality the edges of 

combined forms. They are very common on quartz, shorl, 

and some other minerals ; and frequently indicate combina- 

tions where only a simple form would otherwise appear to 

exist. The cubes and pentagonal dodecahedrons of iron


pyrites are frequently striated, and in three directions at 

right angles to each other. In calc-spar the faces of the 

rhombohedron, JR (g in fig. 43 above) are almost never 

without striae parallel to the oblique diagonal. The stria- 

tion is said to be simple when only one series of parallel 

lines appears on each face, or feathered when two systems 

diverge from a common line. In other crystals the faces, 

then said to be drusy, are covered by numerous projecting 

angles of smaller crystals; an imperfection often seen in 

fluor spar. The faces of crystals occasionally appear curved 

either, as in tourmaline and beryl, from the peculiar oscil- 

latory combination mentioned, or by the union of several 

crystals at obtuse angles, like stones in a vault, as in stilbite 

and prehnite. A true curvature of the faces probably oc- 

curs in the saddle-shaped rhombohedrons of brown spar 

and siderite, in the lens-like crystals of gypsum, and in the 

curved faces so common on diamond crystals. In chabasite 

similar curved faces occur, but concave. In galena and 

augite the crystals are often rounded on the corners, as if by 

an incipient state effusion. On other crystals the faces are 

rendered uneven from inequalities following no certain rule. 

These imperfections furnish valuable assistance in develop- 

ing very complex combinations, all the faces of each individual 

form being distinguished by the same peculiarity of 

surface. 

Irregularities in the forms of crystals are produced when 

the corresponding faces are placed at unequal distances 

from the centre, and consequently differ in form and size. 

Thus the cubes and octahedrons of iron pyrites, galena, and 

fluor spar, are often lengthened along one axis. Quartz is 

subject to many such irregularities, which are seen in a very 

remarkable manner on the beautiful transparent and sharply 

angular crystals from Dauphine. In such irregular forms, 

instead of one line, the axes are then represented by an

FOKM OF MINERALS. 57 

infinite number of lines, parallel to the ideal axis of the 

figure. The same irregularity carried to a greater extent 

frequently causes certain faces required for the symmetry 

of the form, altogether to disappear. Again, some crystals 

do not fill the space marked out by their outline, holes and 

vacancies being left in the faces, occasionally to such an 

extent that they seem little more than mere skeletons. 

This appearance is very common on crystals produced artificially, 

as in common salt, alum, bismuth, silver, &c. A 

perfect crystal can only be produced when, during its formation, 

it is completely isolated, so as to have full room to 

expand on every side. Hence the most perfect crystals 

have been originally imbedded singly in some uniform rock 

mass. Next to them in perfection are forms that grow 

singly, on the surface of some mass of similar or distinct 

composition, especially when the point of adherence is 

small. An incompleteness of form, or at least a difficulty 

in determining it, arises from the minuteness of some crys- 

tals, or from their contracted dimensions in certain direc- 

tions. Thus some appear mere tabular or lamellar planes, 

while others run out into acicular, needle-shaped, or capillary 

crystals. Amid all these modifications of the general 

form of the crystal, of the condition and aspect of its indi- 

vidual faces, or of its linear dimensions, one important ele- 

ment, the angular measurement, remains constant. In some 

monoaxial crystals, indeed, increase of temperature produces 

an unequal expansion in different directions, slightly changing 

the relative inclination of the faces, but so small as to 

be scarcely perceptible in common measurements, and hence 

producing no ambiguity. More important are the angular 

changes which in many species accompany slight changes 

in chemical composition, particularly 

in the relative proportions 

of certain isomorphous elements. But notwithstanding 

these limitations, the great truth of the permanence of


the angular dimensions of crystals, announced by Rome de 

1'Isle, remains unaffected; only, as Mohs well states, it 

must not be interpreted with a rigid immutability, incon- 

sistent with the whole analogy of other parts of nature. 

The Goniometer and Measurement of Crystals. 

The fact just stated of the permanence of the angular di- 

mensions of crystals, shows the importance of some accurate 

method of measuring their angles ; that is, the inclination 

of two faces to each other. 

Two instruments have been 

specially used for this purpose, 

the common or contact 

goniometer, invented by Ca- 

ringeau, and the reflecting goniometer 

of Wollaston. The 

former is simply two brass 

rulers turning on a common 

centre, between which the 

crystal is so placed 

that its 

faces coincide with the edges 

of the rulers, and the angle is 

then measured on a graduated 

arc. This instrument is suffi- 

ciently accurate for many pur- 

poses and for large crystals ; 

but for precise determination 

is far inferior to the reflecting 

goniometer. This requires 

smooth and even faces, but 

these may be very small, even 

Fig. 69. 

the hundredth of an inch, in skilful hands ; and as small 

crystals are generally most perfect, far greater accuracy can


be attained, and the measurement depended on to one 

minute (!'). 

The reflecting goniometer is represented in fig. 69. It 

consists essentially of a graduated circle mm, divided on its 

edge into twice 180, or more often into half degrees, the 

minutes being read off by the vernier hh. This circle turns 

this the 

on an axis connected with ft, so that by turning 

circle is moved round, but is stopped at 1 80, when moving 

in one direction, by a spring at k. The other part of the 

instrument is intended to attach and adjust the crystal to 

be measured. The first axis of mm is hollow, and a second 

axis, , passes through it from ss, so that this and all the 

connected parts from b tof can be turned without moving 

the circle mm. The axis d passes through a hole in be, so 

that it can turn the arm de into any required position ; f is 

a similar axis turning the arm og and ; pq a fourth axis, in 

like manner movable in g, and with a small knob at q, to 

which the crystal to be measured is attached. 

When about to use the instrument, it should be placed 

on a table, with its base horizontal, which is readily done 

by the screws in it, and opposite to a window at about 12 

or 15 feet distance, so that its axis shall be parallel to the 

horizontal bars of the window. One of the upper bars of 

the window, and also the lower bar, or, instead of the lat- 

ter, a white line on the floor or table parallel to the window, 

should then be chosen in order to adjust the crystal. The 

observer places himself behind the instrument with the side 

a at his right hand. The crystal is then attached to q by 

a piece of wax, with the two faces to be measured upward. 

The axis fo is made parallel to o#, and the eye being 

brought near to the first face of the crystal, the axes aa 

and p are turned till the image of the window is seen reflected 

in the face with the horizontal and vertical bars in 

their position. The axis d is then turned through a con-


siderable angle (say 60), and the image of the window 

again sought and brought into its proper place by turning 

the axis/", without moving p. When this is done, that face 

is brought into its true position, normal to d, so that no 

motion of d can disarrange it. Hence the image of the 

window may now be sought in the second face and brought 

into its true position, with the horizontal bars seen horizon- 

tal, by moving the axes d and a. When this is done the 

crystal is properly adjusted, and the angle is thus measured. 

First bring the zero of the circle and vernier to coincide, 

and then turn the inner axis a or as, and move the eye till 

the image of the upper bar of the window reflected from 

the more distant face of the crystal coincides with the lower 

bar or horizontal line seen directly. Keeping the eye in 

its place, turn the outer axis tt till the reflected image of 

the upper bar in the other face in like manner coincides 

with the lower line, and the angle of the two faces is then 

read off on the divided circle. As the angle measured is 

not directly that of the faces, but of the rays of light re- 

flected from them, or the difference of the angle wanted 

from 180, the circle has the degrees numbered in the reverse 

direction, so as to give the angle without the trouble 

of subtracting the one from the other. 

The above apparatus for adjusting the crystal is an im- 

provement suggested by Naumann. In the original instrument 

the axis fo was made to push in or out in a sheath, 

and had a small brass plate, bent at right angles, inserted 

in a cleft at o, to which the crystal was attached. The crystal 

was adjusted, as formerly, by moving the plate, or the 

axis/b, and by slight motion of the arm de, which should 

be at right angles nearly to be when used. A considerable 

improvement is, to have a small mirror fixed on the stand 

below the crystal, with its face parallel to the axis aa, and 

inclined at 45 to the window, when the lower line can be


dispensed with, and the instrument used for various other 

purposes of angular measurement. Many alterations have 

been suggested for the purpose of insuring greater accuracy, 

but the simple instrument is sufficient for all purposes of determinative 

mineralogy, and the error from the instrument 

will in most cases be less than the actual variations in the 

dimensions of the crystals. Greater simplicity is indeed 

rather desirable, and the student will often find it sufficient 

to attach the crystal by a piece of wax to the axis a directly, 

and give it the further adjustment by the hand. The only 

use of the parts from b to q is to enable the observer to 

place the crystal properly ; that is, with the edge to be 

measured parallel to the axis of the instrument, and as 

nearly as possible coinciding with its centre. This is 

effected when the reflection of the horizontal bar in the 

two faces appears parallel to that edge. 

Modes or Twin Crystals. 

When two similar crystals of a mineral species are united 

with their similar faces and axes parallel, the one forms 

merely a continuation or enlargement of the other, and 

every crystal may be regarded as thus built up of a number 

of smaller crystals. Frequently, however, crystals are 

united according to precise laws, though all their similar 

faces and axes are not parallel, and then are named macles 

or twin crystals. In one class of macles the axes of the 

two crystals are parallel, and in another they are inclined. 

The former only occur among hemihedric forms, and the 

two crystals are then combined in the exact position in 

which they would be derived from or reproduce the pri- 

mary holohedric form. The second class, with oblique 

axes, occur both in holohedric and hemihedric forms, and 

the two individuals are placed in perfect symmetry to each


other, in reference to a particular face of the crystal which 

forms the plane of union, or the equator of the made. We 

may also suppose the two crystals originally parallel, and 

the one turned round the normal of the united faces by 180 

(often 90 or 60), while the other is stationary. 

Or we 

may suppose a crystal cut into halves in a particular direc- 

tion, and one half turned 1 80 on the other ; and hence the 

name of hemitrope given to them by Hauy. The position 

of the two individuals in this case corresponds with that of 

an object and its image in a mirror, whose surface then 

represents the plane of union. 

The manner in which the crystals unite also differs. 

Some are merely opposed or in simple contact ; others are, 

as it were, grown together, and mutually interpenetrate, 

occasionally so completely as to appear like one individual. 

The twin edges and angles in which the two unite are often 

when the 

re-entering ; or they may coincide in one plane, 

line of union is either imperceptible, or is only marked by 

the meeting of two systems of striae, or other diversity in 

the physical characters of the two faces. 

The formation of twin crystals may be again repeated, 

forming groups of three, four, or more. When the faces of 

union are parallel to each other, the crystals form rows of 

indeterminate extent; where they are not parallel, they 

may return into each other in circles, or form bouquet-like 

or other groups. Where crystals are merely in juxtaposition, 

they are sometimes much shortened in the direction 

occur in a series with 

of the twin axis ; and where many 

parallel position, are often compressed into very thin plates, 

frequently not thicker than paper, giving to the surface of 

the aggregate a peculiar striated aspect. 

Only a few twin crystals in the different systems can be 

noticed, chiefly as examples of this mode of formation. In 

the tesseral system, forms that unite with parallel axes pro-

F011M OF MINERALS. 63 

duce intersecting macles like the pentagonal dodecahedrons 

of iron pyrites in fig. 70, and the tetrahedrons of gray-cop- 

Fig. 70. Fig. 71. 

per or fhhlore in fig. 71, a similar formation also occurring ' 

in the diamond. In macles with inclined axes the two 

forms almost always unite by a face of the octahedron, and 

the two individuals are then generally apposed and short- 

ened in the direction of the twin axis by one half, so that 

they appear like a crystal that has been divided by a plane 

parallel to one of its faces, and the two halves turned round 

on each other by an angle of 180. In this manner two 

octahedrons of the spinel, magnetic iron ore, or automolite 

Fig. 72. Fig. 73. 

(fig. 72), are frequently united. The same law prevails in 

the intersecting cubes of fluor spar, iron pyrites, and galena,


represented in fig. 73. In fig. 74 of zinc-blende, two rhombic 

dodecahedrons are united by a face of the octahedron. 

In the Tetragonal system, twin crystals with parallel axes 

Fig. 74. Fig. 75. 

rarely occur, but are seen in chalcopyrite, and one or two 

other minerals. Where the axes are inclined the plane of 

union is very often one of the faces of the pyramid Poo , or 

one of those faces that would regularly replace the polar 

edges of the fundamental form P. The crystals of tin ore 

obey this law, as seen in fig. 75, where the individuals are 

pyramidal, and in the knee-shaped crystal (fig. 76), where 

Fig. 76. Fig. 77. 

they are more prismatic. 

Hausmanite appears like fig. 77, 

in which the fundamental pyramid P prevails, on whose polar 

edges other crystals are often very symmetrically repeated.


a central individual appearing like the support of all the 

others. Almost identical forms occur in chalcopyrite. 

In the Hexagonal system, twin crystals with parallel axes 

are common, as in calc-spar, chabasite, hematite, and other 

rhombohedric minerals. In calc-spar they often form very 

regular crystals, the two individuals uniting by a plane 

parallel to the base, so as to appear like a single crystal, as 

in fig. 78, where each end shows the forms ooR. R, but 

in a complementary position ; or in fig. 79 of two scaleno- 

hedrons R3 from Derbyshire. The rhombohedric crystals 

of chabasite often appear intersecting each other, like those 

of fluor spar in fig. 73. The purer varieties of quartz or 

Fig. 78. Fig. 79. Fig. 80. 

rock crystal, in consequence of the tetartohedric character 

of its crystallization, often exhibit twins. In these the 

pyramid P separates into two rhombohedrons P and z, 

which, though geometrically similar, are yet physically 

distinct. In fig. 80 the two individuals are only grown to- 

gether, but more commonly they penetrate each other in 

an irregular manner, forming apparently a single crystal. 

Twins with oblique axes are also common, the plane of 

union being usually one face of the rhombohedron. Thus 

in calc-spar two rhombohedrons are often joined by a face


of gll, the two axes forming an angle of 127 34'; occa- 

sionally a third individual is interposed in a lamellar form, 

as in fig. 81, when the two outer crystals become parallel. 

Fig. 81. Fig. 82. 

This latter arrangement is very common in the highly 

cleavable varieties of Iceland spar. When the crystals 

unite in a face of the rhombohedron R, fig. 82, they form 

an angle of 89 8', differing little from a right angle, by 

which the occurrence of this law is very easily recognized, 

especially in prismatic varieties. 

In the rhombic system, twin crystals with parallel axes 

are very rare, but those with oblique axes common, the 

GO P. 

plane of union being one of the faces of the prism 

Twins of this kind are very distinctly seen in arragonite, 

Fig. S3. Fig. 84 Fig. 85. 

carbonate of lead, marcasite, stephanite, mispickel, and 

other minerals. In arragonite the crystals partly interpen-

FORM OF MINERALS. 6-7 

etrate, partly are in mere juxtaposition, as in fig. 83, where 

the individuals are formed by the Combination ooP(Jlf) . 

oo Poo (A), Poo (&), and in figure 84 where several crystals 

of the same combination form a series with parallel planes 

of union ; the inner members being so shortened that they 

appear like mere lamellar plates producing 

striae on the 

faces Poo and ooPoo of the made. In fig. 85 four crystals, 

each of the combination ooP . 2Poo , having united in in- 

clined planes, form a circular group, returning into itself. 

The carbonate of lead often occurs in macles in all respects 

Fig. 86. Fi . ? 87. 

similar. In staurolite, individuals of the prismatic combition 

oo P . oo Poo . OP, combine either, as in 

fig. 86, by a 

face of the braehydome |Poo , with their 

chief axes almost at right angles; or, as in 

fig. 87, by a face of th brachypyramid 

fP|, the chief axes and the brachypinacoids 

(o) of the two single crystals meeting 

at an angle of about 60. Finally, in fig. 

88, two harmotome crystals of the most 

common combination ooPoo . ooPoo . P . 

Poo , intersect each other so nearly at right 

angles, that their principal axes seem to Fig.88. 

coincide, and the brachypiuacoid (q) of the one crystal


(with a rhombic striae) is parallel to the macropinacoid (q) 

of the other. 

In -the monoclinohedric system the most common macles 

are those in which the principal axes and the chief sections 

of the two crystals are parallel to each other, and conse- 

quently the principal axis is also the twin axis. Usually 

the two individuals are united by a face parallel to the or- 

thodiagonal chief section, as in figure 89 of gypsum, where 

two crystals of the combination (ooPco).ooP. P, shown 

in fig. 59, unite so regularly that the faces of the pinacoids 

(P and P') form only one plane. 

In a similar manner the 

augite crystals of the combination ooP. ooPoo . (ooPoo). 

P, represented singly in fig. 60, are in fig. 

90 united in a 

Fig. 89. Fig. 90. Fig. 91. 

macle so very symmetrical and regular that the line of 

junction cannot be observed on tlie face of the clinopinacoid. 

The two hemipyramids P (s) (like P (I) in the gypsum 

crystal above) form on one side a re-entering, on the other 

a salient angle. Hornblende, wolfram, and other minerals 

exhibit a similar appearance. In other cases the individuals 

partially penetrate each other, being, as it were, crushed 

together in the direction of the orthodiagonal. This mode 

of union is not uncommon in gypsum, and very frequent in 

orthoclase felspar. Two crystals of the latter, of the com-

FOKM OF MINERALS. 69 

bination ( ooPoo ) . ooP . OP . 2Poo , as in fig. 61 above, are 

often pushed sidewise into each other, as shown in fig. 91. 

In the triclinohedric system, some twin formations are of 

great importance as a means of distinguishing the triclinohedric 

from the monoclinohedric species of felspar. In one 

variety the twin axis is the normal to the brachydiagonal 

chief section. But in the triclinohedric felspars this sec- 

tion is not, as it is in the monoclinohedric species, perpendicular 

to the basis, and consequently the two bases form 

on one side a re-entering, on the other a salient angle ; 

whereas in the monoclinohedric felspars (where the brachydiagonal 

chief section corresponds to the clinodiagonal), no 

twin crystals can be produced in conformity to this law, and 

the two bases fah 1 

in one plane. The albite and oligoclase 

very often exhibit such twins, as in figure 92, where the 

Fig. 92. 

very obtuse angles formed by the faces of OP, or P and P' 

(as well as those of 'P'oo , or x and #'), are a very charac- 

teristic appearance, marking out this mineral at once as a 

triclinohedric species. Usually the twin formation is re- 

peated, three or more crystals being combined, when those 

in the centre are reduced to mere plates. When very nu- 

merous, the surfaces P and x are covered with fine striae, 

often only perceptible with a microscope. A second law


observed in triclinohedric felspars, particularly the albite 

and labradorite, is that the twin axis corresponds with that 

normal of the brachydiagonal which is 

situated in the plane of the base. In 

pericline, a variety of albite, these twins 

appear as in fig. 93, where the two crystals 

are united by a face of the basal 

pinacoid P, while the faces of the two 

brachypinacoids (Jffand M') form edges 

with very obtuse angles (1*73 22'), re- 

entering on the one side and salient on 

the other. These edges, or the line of 

Fig. 93. 

junction between JbTand Jtf'9 are also parallel to the edges 

formed by these faces and the base, or those between M 

and P. In this case also the macles are occasionally sev- 

eral times repeated when the faces appear covered with fine 

stria3. 

Irregular Aggregation of Crystals. 

Besides the regular unions now described, crystals are 

often aggregated in peculiar ways, to which no fixed law 

can be assigned. Thus some crystals, apparently simple, 

are composed of concentric crusts or shells, which may be 

removed one after the other, always leaving a smaller crys- 

tal like a kernel, with smooth distinct faces. Some speci- 

mens of quartz from Beeralston in Devonshire consist apparently 

of hollow hexagonal pyramids placed one within 

another. Other minerals, as fluor spar, apatite, heavy spar, 

and calc-spar, exhibited a similar structure by bands of dif- 

ferent colors. 

Many large crystals, again, appear like an aggregate of 

numerous small crystals, partly of the same, partly of different 

forms. Thus some octahedrons of fluor spar from 

Schlaggenwald are made up of small dark violet-blue cubes,


whose projecting angles give a drusy character to the faces 

of the larger form. Such polysynthetic crystals, as they 

may be called, are very common in calc-spar. 

A similar, but still more remarkable formation, is where 

two crystals of distinct species are conjoined. Such unions 

of cyanite and staurolite have been long well known, and 

the graphic-granite exhibits a similar union between large 

felspar crystals and many smaller ones of mica and quartz. 

Forms of Crystalline Aggregates. Crystals have often 

been produced under conditions preventing the free de- 

velopment of their forms. They then compose crystalline 

aggregates, of which the following may be distinguished : 

Granular, formed of grains, generally angular, but rarely 

rounded or flattened. Lamellar consist of broad plates, 

which are tabular when of uniform thickness, lenticular 

when becoming thinner on the edges, icedge-shaped when 

sharpened towards one edge, and scaly when the plates are 

very small. Columnar, in which the individuals are drawn 

out in one direction more than in the others ; bacittary or 

rod-like, in which the columns are of uniform thickness ; 

acicular or needle-shaped,, in which they are pointed; and 

fibrous, in which they are very fine. In the broad-columnar 

the columns are, as it were, compressed, or broader in 

one direction than the other. The distinctions of large, 

coarse, small, or fine-granular ; thick or thin scaly ; straight, 

curved, or twisted- columnar ; parallel, diverging, or con- 

fused-fibrous ; 

and such like, are easily understood. 

Aggregates which have been able to crystallize, at least, 

with a certain degree of freedom, have been distinguished 

by Mohs into crystal groups and druses : the former includ- 

ing all unions of several imbedded crystals ; the latter those 

of crystals that have grown together on a common support. 

In the groups, crystals with their faces otherwise perfect 

are conjoined in various ways. Sometimes they radiate, as


it were, from a common centre, and produce spheroidal, el- 

lipsoidal, or other forms, frequent in gypsum, iron pyrites, 

and other minerals imbedded in clay. Where many such 

masses are united, they are named botryoidal when like 

bunches of grapes, mammellated where the spheres are 

larger and less distinct, and reniform or kidney-shaped 

where the masses are still larger. Some groups are partially 

attached by a small point ; but the mass is generally 

free. 

Crystals are often grouped in rows or in one direction, 

forming, when they are very small, capillary or hair-like, 

and filiform, thread, or wire-like forms, which are common 

among native metals, as gold, silver, copper, and bismuth, 

in silver glance and a few other materials. Sometimes the 

masses are dentiform, consisting of portions resembling 

teeth ; as is very common in silver. Often these groups 

expand in several directions, and produce arborescent, 

dendritic, foliated, feathered, or other forms, very common 

in copper. In these groups, however, a certain dependence 

on the crystallographic character of the species may be 

observed. The lamellar minerals often form fan-shaped, 

wheel-like, almond-shaped, comb-like, or other groups. 

The fibrous types, again, are disposed in parallel or diverging 

bundles, or in radiating, stellar, and other masses. 

Coralloidal (like coral), fruticose (like cauliflower), and other 

forms, have also been observed. 

In druses, many crystals rise side by side from a common 

support sometimes ; 

only the granular mass composed of 

their united bases, at other times some distinct body. The 

form of a druse is determined by that of the surface on 

which it grows, and consequently is often very irregular or 

wholly accidental. Where completely inclosed they have 

been named drusy cavities, and when of a spheroidal form, 

geodes. A drusy crust, again, consists of a thin layer of


small crystals investing the surface of a large crystal or" of 

some othep body. 

The minute or cryptocrystalline minerals form similar 

aggregates. In the globular or the oolitic, the minute crystals 

often appear to radiate from a centre, or form concen- 

tric crusts. Somewhat -similar are the stalactites and sta- 

lagmites, in which the mineral, especially rock-salt, lime- 

stone, chalcedony, opal, limonite, has been deposited from 

a fluid dropping slowly from some overhanging body. In 

this case the principal axis of the figure, generally a hollow 

tube, is vertical, while the individual parts are arranged at 

right angles to this direction. In other cases the mineral 

has. apparently been deposited from a fluid mass moving 

slowly in a particular direction, which may be regarded as 

the chief axis- of the figure, while the axes of the indi- 

vidual crystals may assume a different position. 

By far the largest masses of the mineral kingdom have, 

however, been produced under conditions in which a free 

development of their forms was excluded. This has been 

the case with the greater portion of the minerals composing 

rocks or filling veins and dykes. The structure of these 

masses on the large scale belongs to geology, but some 

varieties of the texture visible even in hand specimens may 

be noticed. The individual grains or masses have seldom 

any regular form, but appear round, long, or flat, according 

.to circumstances, and as each has been more or less checked 

in the process of formation. Even then, however, a cer- 

tain regularity in the position of the parts is often observ- 

able, as in granite, in which the cleavage planes, and con- 

sequently the axes of the felspar crystals, are parallel. 

Where these grains are all pretty similar in size and shape, 

the rock is named massive when they are small, or granular 

when they are larger and more distinct. Sometimes the rock 

becomes slaty, dividing into thin plates ; 

4 

or concretionary,

74 A POPULAR TREATISE ON 'GEMS. 

forming roundish masses ; at other times the interposition 

of some foreign substance (gas or vapor) has renderetl it 

porous, cellular or vesicular, giving rise to drusy cavities. 

These cavities are often empty, but have occasionally been 

filled by other minerals, when the rock is named amygdaloidal, 

from the almond-like shape of the inclosed masses. 

Many of the above external forms appear also in the 

amorphous solid minerals, in which no trace of individual 

parts, and consequently of internal structure, is observable. 

They are not unfrequently. disposed in parallel or concen- 

tric layers, of uniform or distinct colors ; and may assume 

spherical, cylindrical, stalactitic, and other appearances. 

Pseudomorphism. When the substance of one mineral 

assumes the external form of some other mineral, it is named 

a.pseudomorph. In some named incrusting pseudomorphs 

the original crystal is covered by a rough or drusy surface 

of the second mineral, frequently not thicker than paper. 

Occasionally the first crystal has been removed, and noth- 

ing but the shell remains ; 

or the cavity has been filled by 

a distinct mineral species, or a crystalloid, as it may .be 

named, forming an exact representation of the original, but 

of a different substance. 

More commonly the new mineral substance has gradually 

expelled the old, and replacing it, as it were, atom by atom, 

has assumed its exact form. In other cases not the whole 

substance of the original crystal, but only one or more of 

its elements, has been changed, or the whole matter has 

remained, but in a new condition. Thus arragonite crystals 

have been converted into calc-spar, the chemical com- 

position of both being identical ; or gaylussite 

has been 

changed into calc-spar, andalusite into cyanite, by the loss 

of certain elements. On the other hand, anhydrite be- 

comes gypsum, red-copper . 

ore malachite, by addition of 

new matter. Or-tho elements are partially changed, as

. FORM OP MINERALS. 75 

felspar T-to kaolin, quartz or pearl spar into talc, iron pyrites 

or iron glance into brown-iron ore> azurite into malachite, 

augite into green earth. The true nature of such bodies is 

shown by the internal structure, having no relation to the 

external form or apparent system of crystallization. 

The process of petrifaction of organic bodies is in reality 

a species of pseud oinorphic formation, and lias been pro- 

duced in all the above modes. External and internal casts 

of organic bodies are not uncommon. In other cases the 

original substance has been replaced by some mineral which 

has preserved not merely the external form, but ev'en the 

"minutest detail of internal structure ; so that the different 

kinds of wood have been distinguished in their silicified 

trunks. The most common petrifying substances are silica 

and carbonate of lime. In encrynites, echinites, belemnites, 

and other fossils, the crystals of calc-spar often occur in 

In some varieties of petrified wood 

very regular positions. 

both the ligneous structure and the cleavage of the calc- 

spar are observable. 

Different from the above are mineralized bodies, in which 

the original structure is still retained, but their chemical 

nature partially changed. In these a complete series may 

be often traced, as from wood or peat, through the varie- 

ties of brown coal, common coal, anthracite, and graphite, 

perhaps even to the diamond. 

CHAPTER II. 

PHYSICAL PROPERTIES OF MINERALS. 

THE physical characters of minerals comprehend, 1st. 

Those properties derived from the nature of the substance 

itself, as coherence, mode of fracturej elasticity, and density

7G A POPULAR TREATISE ON" GEMS. . 

or specific gravity ; 2cl Those phenomena called forth in 

minerals by the influence of some external power or agent, 

as their optical, electric, or thermal relations; and, 3d. 

Other characters depending on the personal sensation of 

the observer on his taste, smell, and touch. All these 

properties furnish useful characters in distinguishing and 

describing mineral species. 

Cleavage and Fracture. 

In many species there are certain planes at right* angles 

to which cohesion seems to be at a minimum, so that the 

mineral separates along or parallel to these planes far more 

readily than in any other direction. This property is named 

cleavage, and these planes cleavage-planes. They have a 

strictly definite position, and do not show any transition or 

gradual passage into the greater coherence in other direc- 

tions. The number of these parallel cleavage-planes is alto- 

gether indefinite ; so that the only limit that can be as- 

signed to the divisibility of some minerals, as gypsum and 

mica, arises from the coarseness of our instruments. 

These minima of coherence or cleavage-planes are always 

parallel to some face of the crystal, and similar equal minima 

occur parallel to every other face of the same form. 

Hence they are always equal in number to the faces of the 

form, and the figures produced by cleavage agree in every 

point with true crystals, except that they are artificial. 

They are thus most simply and conveniently described by 

the same terms and signs as the faces of crystals. Some 

minerals cleave in several directions parallel to the faces of 

different forms, but the cleavage is generally more easily 

obtained and more perfect in one direction than in the 

others, This complex cleavage is well seen in calc-spar 

and fluor spar, and very remarkably in zinc-blende, where

PHYSICAL PROPERTIES OF MINERALS. 77 

it takes place in no less than six directions. As in each of 

these the division may be indefinitely continued, 

it is clear 

that no lamellar structure in any proper sense can be as- 

signed to the mineral. All that can be affirmed is, that 

atoms have less coherence in the normal of these 

contiguous 

planes than in other directions. When the cleavage takes 

place in three directions, it of course produces a perfect 

crystal form, from which the system of crystallization and 

angular dimensions of the species may be discovered, and 

is thus often of very great importance. 

The common cleavage in the different systems is as fol- 

lows, those of most frequent occurrence being put in italics. 

(1.) In the tessera), Octahedric, O, along 

the faces of the 

octahedron ; Bexahedric, ooOoo , alonij those of the cube , 

and Dodecahedric, o>O. (2.) In the tetragonal system, 

Pyramidal, P or 2Poo ; Prismatic, ooP or ooPoo; or Ba- 

sal, OP. (3.) In the hexagonal system 

with holohedric 

forms, Pyramidal, P or P2 ; Prismatic, ooP or ooP2 or 

; 

Basal, OP with rhombohedral ; 

forms, EhomboJiedric, R ; 

Prismatic, oo R ; or Basal, OR. (4.) In the rhombic sys- 

tem, Pyramidal, P; Prismatic, ooP; Makro or Brachy- 

domatic, Poo or Poo; Basal, OP; Macrodiagonal, ooPoo; 

or Br'achy'diagonal, ooPoo . 

(5.) In the monoclinohedric 

system, Hemipyramidal, P or P; Prismatic, ooP; Clinodomatie 

(Pô) ; Hemidomatic, Poo or Poo; Basal, OP; 

Orthodiagonal, ooPoo; or Clinodiagonal (ooPoo). (6.) 

In the triclinohedric system, Hemiprismatic, ooP' oroo'P; 

Hemidomatic either along the macrodome or brachydome ; 

Basal, OP; Macrodiagonal, ooPoo; or Br achydiagonal, 

00 P 00. . 

In some minerals the cleavage is readily procured ; in 

others only with extreme difficulty. 

The planes produced 

also vary much in their degree of perfection, being highly 

perfect in some, as mica and gypsum ; imperfect in others,

78 A POPULAR TREATISE ON GESTS. 

as garnet and quartz. In a very few crystalline minerals 

cleavage-planes can hardly be said to exist. Cleavage must 

be carefully distinguished from the planes of union in twin 

crystals, and the division-planes in the laminar minerals. 

Fraeture surfaces are formed when a mineral breaks in 

a direction different from the cleavage-planes. They are 

consequently most readily observed when the cleavage is 

least perfect. The form of the fracture is named conchoidal 

when composed of concave and convex surfaces like shells, 

even when nearly free from inequalities. The character of 

the surface is smooth / or splintery when covered by small 

wedge-shaped splinters adhering by the thicker end; or 

hackly when covered by small slightly-bent inequalities, as 

in iron and other malleable bodies ; 

only fine dust. 

Hardness and Tenacity. 

or earthy when it shows 

The hardness of minerals, or their power of resisting any 

attempt to separate their parts, is also an important charac- 

ter. As it differs considerably in the same species, accord- 

ing to the direction and the surface on which the trial is 

made, its accurate determination is difficult, and the utmost 

that can usually be obtained is a mere approximation found 

by comparing different minerals one with another. For 

this purpose Mobs has given the following scale : 

1. Talc, of a white or greenish color. 

2. Rock-salt, a pure cleavable variety, or semi-transparent uncrystallizea 

gypsum,, the transparent and crystallized varieties being generally too soft. 

8. Calcareous spar, a cleavable variety. 

4. Fluor spar, in which the cleavage is distinct. 

5. Apatite,\.\\Q asparagus-stone, or phosphate of lime. 

6. Adularia felspar, any cleavable variety. 

7. Rock- crystal, a transparent variety. 

8. "Prismatic topaz, any simple variety. 

9. Corundum, from India, which affords smooth cleavage surfaces. 

10. The Diamond.


Two other degrees are obtained by interposing foliated 

mica between 2 and 3, and scapolite, a crystalline variety, 

between 5 and 6. The former is .numbered 2'5, the lat- 

ter 5*5. 

To ascertain the hardness of a mineral, first try which of 

the members of the scale is scratched by it, and in order to 

save the specimens, begin with the highest numbers, and 

proceed downward, until reaching one which is scratched. 

Then take a finer hard file, and draw along its surface, with 

the least possible force, the specimen to be examined, and 

also that mineral in the scale whose hardness is immediately 

above the one which has been scratched. From the resist- 

ance they offer to the file, from the noise occasioned by 

their passing along it, and from the quantity of powder left 

on its surface, their relative hardness is deduced. When, 

after repeated trials, we are satisfied to which member of 

the scale of hardness the mineral is most nearly allied, we 

say its hardness (suppose it to be felspar) is equal to 6, and 

write after it H.=:6'0. If the mineral do not exactly cor- 

respond with any degree of the scale, but is found to be 

between two of them, it is marked by the lower with a de- 

cimal figure added. Thus, if more than 6 but less than 7, 

it is expressed H.=6'5. In these experiments we must be 

careful to employ specimens which nearly agree in form 

and size, and also as much as possible in the shape of their 

angles. 

Where the scale of hardness is wanting, or for a first 

rough determination, the following experiments may 

serve : 

Every mineral that is scratched by the finger-nail has H. = 2-5 or less. 

Minerals that scratch copper have H. = 3 or more. 

Polished white iron has H. = 4-5. 

JVindow-glass has H. = 5 to 5*5. 

Steel point or file has H. = 6 to 7. 

Hence every mineral that will cut or scratch with, a good penknife has 

H. less than 6.


Flint has H. = 7, and only about a dozen minerals, including the precious 

atones or gems, are harder. 

Precious stones have latterly been divided and arranged 

according to their hardness, in the following three classes 

1. HARD OEMS ; OB THOSE HARDER THAN QUARTZ. 

Diamond. Topaz. 

Sapphire. 

Emerald. 

Ruby. Hyacinth. 

Chrysoberyl. 

Essonite. 

Spinelle. 

Garnet. 

2. SEMI-HARD JEWELS. 

Eock Crystal. Opal. 

Amethyst. Chrysolite 

Chalcedony. 

Lazulite. 

Carnelian, and other Obsidian, 

similar ones. Turquoise. 

3. SOFT PRECIOUS STONES. 

Those softer than Fluor-spar ; Malachite, Amber, and Jet. 

Closely allied to hardness is the TENACITY of minerals, of 

which the following varieties have been distinguished : A 

mineral is said to be brittle when, as in quartz, on attempting 

to cut it with a knife, it emits a grating noise, and the 

particles fly away in the form of dust. It is sectile or mild 

when, as in galena and some varieties of mica, on cutting, 

the particles lose their connection in a considerable degree ; 

but this takes place without noise, and they do not fly off, 

but remain on the knife. And* a mineral is said to be soft 

or 'ductile when, like native gold or lead, it can be cut into 

slices with a knife, extended under the hammer, and drawn 

into wire. From tenacity it is usual to distinguish frang I- 

bility) or the resistance which minerals oppose when we at- 

tempt to break them into pieces or fragments. This prop- 

erty must not be confounded with, hardness. Quartz is 

hard, and hornblende comparatively soft ; yet 

> 

the latter is

PHYSICAL PROPERTIES OP MINERALS. 81 

|| 

more difficultly frangible than the former. 

Flexibility 

again expresses the property possessed by some minerals 

of bending without breaking. They are elastic, like mica, 

if, when bent, they spring back again into their former di- 

rection ; 

or merely flexible, when they can be - bent in dif- 

ferent directions without breaking, but remain in their new 

position, as gypsum, talc, asbestus, and all malleable min- 

erals. 

Specific Gravity. 

The density or the relative weight o*f a mineral, com- 

is named 

pared with an equal volume of pure distilled water, 

its specific gravity. This is a 

most important character for dis- 

tinguishing minerals, 

as it varies 

considerably in different species, 

and can be readily ascertained 

with much accuracy, and in many 

cases without at ah 1 

injuring the 

specimen. The whole process con- 

sists in weighing the body, first in 

air, and then immersed in water, 

the difference in the weight being 

that of an equal bulk of the latter 

fluid. Hence, assuming, as is com- 

monly done, the specific gravity 

of pure distilled water to be equal 

. Fig. 94. 

to 1 or unity, the specific gravity 

(G) of the other body is equal to its weight in air (w), divided 

by the loss or difference (G) of weight in water (or 

G=5. A simple and portable instrument for finding the 

specific gravity is a hydrometer of Nicholson, fig. 

94. A 

delicate hydrostatic balance gives the gravity with far more 

40


accuracy; and even a good common balance is often pieferable. 

The mineral may be suspended from one arm or 

scale by a fine silk thread or hair, and its weight ascer- 

tained, first in the air, and then in water. 

There are a few precautions necessary to insure accuracy. 

Thus, a pure specimen must be selected which is not intermixed 

with other substances, and when weighed in air it 

should be quite dry. It must also be free from cavities, 

and care must be taken that when weighed in water no 

globules of air adhere to its surface, which render it lighter. 

If the body imbibos moisture, it should be allowed to remain 

till fully saturated before determining its weight when 

immersed, and it is sometimes even necessary to boil the 

specimen in order to expel the air from its pores. Small 

crystals or fragments, whose freedom from mixture can be 

seen, are best adapted for this purpose. The specimen 

experimented on should not be too heavy ; thirty grains 

being enough where the gravity is low, and even less where 

it is high. It is also of importance to repeat the trial, if 

possible with different -specimens, which will show whether 

any cause of error exists, and to take the mean of the 

whole. A correction should be made for the variation of 

the temperature of the water from 60 Fahr., which is that 

usually chosen as the standard in mineralogical works. 

Where the difference, however, does not exceed ten or fif- 

teen degrees, this correction may be neglected, as it only 

affects the third or second decimal figure of the result. 

By determining the specific gravity of minerals with the 

hydrostatic balance, we proceed, for instance : an unknown, 

mineral having been weighed first in the air, and then fast- 

ened by means of a hair and weighed in water. Such as 

in the air 17 "65; in water 12*35. The loss in water is, 

therefore, 5 '30; and this number indicates the loss of so 

much bulk of water displaced by the mineral putting the

PfiYSICAL PROPERTIES OF MINERALS. 83 

specific gravity of water 1*00: x dividing 5 into 17'65, 

make it equal to 3 '5 3, which is the exact specific gravity 

of the mineral, and which is that of essonite. Instead of a 

hydrostatic balance, we may as "well use Nicholson's hydrometer, 

a simple and Aêry convenient instrument, cot> 

sisting of a hollow glass cylinder (A), and two dishes (B 

and C) filled with lead, in order to keep the instrument 

upright. The hydrometer is put-in a glass vessel (E), filled 

with water, and used as follows : 

1st. The weight is determined which is required to sink 

the instrument to the mark D in water. 

2d. The mineral is put in the dish A over the weight 

noted, that 'is required, in addition to the mineral, to sink 

the hydrometer to D. 

3d. The same experiment is repeated by putting the 

mineral, after being moistened and washed with water, in 

the dish C ; and now is A B the weight of the mineral in 

the air, and B b the weight of a quantity of water equal 

in volume to that of the mineral. 

For instance, let A = 32'8 

B = 7-3 

C = 15'8 

there is (A b) 32*8 7*3 = 25*5 the weight of the mineral 

in the air. 

(C b) 15*8 7*3 = 8*5 the weight of an equal quantity 

of water, and proceed 8*5 : 25*5 = 1 : x 

8-5 

= 3*00, which is the proper specific 

gravity. For determining the specific gravity of substances 

or minerals lighter than water, or which float in water, it 

is necessary to adhere to the same method by the hydrometer. 

A heavier body, such as lead, after determining the


difference of weight, within or without the water, of both 

together, and then of the heavier body alone, the specific 

gravity of the lighter substance is the result. And for determining 

the specific gravity of liquids, by means of the 

hydrostatic balance, a glass ball is applied to one of the 

arms (its 

loss of weight in pure water being known), and, 

dipping the same in the liquid to be examined, any addition 

and abstraction will result in the specific gravity of the 

liquid. The hydrometers of Beaume for the different 

liquids to be examined, are employed with satisfactory 

results. 

That the specific gravity has been known as far back as 

the thirteenth century, and applied by the Oriental nations 

for determining the character of precious stones, is sufficiently 

proved by a work written in that century by Mohammed 

Ben Manner. In fact, the specific gravity is often, 

in connection with the color, quite essential in determining 

a gem. 

Optical Properties of Minerals. 

There are few more interesting departments of science 

than the relations of mineral bodies to light, and the modi- 

fications which it undergoes either when passing through 

them or when reflected from their surface. In this place, 

however, we can only notice these phenomena so far as 

they point out distinctions in the internal constitution of 

minerals, or furnish characters for distinguishing one species 

from another. 

Minerals, and even different specimens of the same spe- 

cies, vary much in pellucidity or in the quantity of light 

which can pass through them. Some transmit so much 

light, that small objects can be clearly seen, or letters read 

when placed behind them, and are named transparent. 

They are semi-transparent when the object is only seen


and translucent when the light 

dimly, as through a cloud ; 

that passes through it is so obscured that the objects can 

be no longer discerned. Some minerals are only thus trans 

lucent on the thinnest edges, and hi others even these trans 

mit no light, and the body is named opaque or untranspa 

rent. These degrees pass gradually into each other, and 

cannot be separated by any precise line ; and' this is also 

the case in nature, where some minerals pass through the 

whole scale, as quartz, from the fine transparent rock-crystal 

to opaque dark-black varieties. Such minerals may be 

described generally as pellucid. This change often arises 

from some mixture in their composition, especially of me- 

tallic substances. Perfect opacity is chieny found in the 

metals or their compounds with sulphur, though even these 

seem to transmit light when reduced to Iamina3 of sufficient 

thinness. 

Double Refraction. When a ray of light passes ob- 

liquely from one medium into another of different density, 

it is bent or refracted from its former course. The line 

which it then follows forms an angle with the perpendicular, 

which in each body bears a certain proportion to 

that at which the ray fell upon, it ; or, as definitely stated, 

the sine of the angle of refraction has a fixed ratio to the 

sine of the angle of incidence, this ratio being named the 

index of refraction. This simple refraction is common to all 

transparent bodies, whether crystalline, amorphous, or fluid ; 

but some crystals produce a still more remarkable result. 

The ray of light which entered them as one is divided into 

two rays, each following different angles, or is doubly re- 

fracted. In minerals of the tesseral system this property 

does not exist, but it has been always observed in minerals 

belonging to the other systems, though in many only after 

they have been cut in a. particular manner, or have been 

otherwise properly prepared. It is most distinctly seen in


crystals of calc-spar, especially in the beautiful transparent 

variety from Iceland, in which it was first observed and 

described by Erasmus Bartholin in a work published at 

in 1669. 

Copenhagen 

The subjoined figure will illustrate this singular proper- 

ty. It represents a 

rhomb of Iceland 

spar, on the surface 

of which a ray of 

light E r falls. As 

seen in the figure, 

this ray divides into 

two, one of which 

rod follows the ordi- 

nary law of refraction, 

or the sines of 

the angles of incidence and refraction maintain a constant 

ratio. This is named the ordinary ray O. The other, 

hence named the extraordinary ray E, does not obey the 

usual law of the sines, and has no general index of refrac- 

tion. In the plane perpendicular to the axis it is most 

widely separated from the ordinary ray, but in others ob- 

lique to it approaches nearer to O, and in one at right 

angles coincides, or there is no double refraction. This 

plane, or rather direction, in which there is no double refraction, 

is named the optical axis of the crystal, or the 

axis of double refraction. Now, in certain minerals, it is 

found that there is only one plane with this property, where- 

as in others there are two such planes, and they have in 

consequence been divided into monoaxial and binaxial. To 

the former (monoaxial) belong all crystals of the tetrago- 

nal and hexagonal systems ; to the latter (binaxial) all 

those of the three other systems. In the former the optic 

axis coincides with, or is parallel to, the crystallographic

PHYSICAL PKOPEKTIES OF MINERALS. 87 

chief axis. In some crystals the index of refraction for the 

extraordinary ray E is greater than for the ordinary ray O ; 

and in others it is smaller. The former are said to have 

positive (or attractive), the latter negative (or repulsive), 

double refraction. Quartz is an example of the former, 

the index of refraction, according to Malus, being for O= 

T5484, for E=l*5582; and calc-spar of the latter, the 

index of O being= 1*6543, of E=l*4833. The index of 

E is in both cases taken at its maximum. 

According to Dufrenoy, the following 

table shows the 

index of refraction of a great number of minerals : 

Chromate of lead ................................ 2-500 to 2-974 

Diamond ........................................ 2-439 to 2'755 

Native sulphur ................................... 2-115 

Carbonate of lead ................................. 2-084 

Zircon ........................................... 1-950 

Garnet ........................................... 1-815 

Spinelle .......................................... 1-812 

Blue corundum (sapphire).. . ...................... 1*794 

Red 

White 

" 

" 

(ruby) ...... '. ..................... 1-779 

(sapphire) ........................ 1-768 

Adularia ......................................... 1-764 

Cymophane (oriental chrysolite) .................... 1-760 

Boracite .......................................... 1-701 

Carbonate strontia ................................ 1*700 

Carbonate lime i extraordinary ray 

( ordinary ray .......................... 1-693 

Arragomte { 

i extraordinary ray ..................... I'o3o 

one of the rays .................... 1*635 

( 

Sulphate baryta , 

the other ray ..................... 1'620 

J 

J 

{ one of the rays ..................... 1*640 

Yellow topaz -I 

.. 

, 

tfon 

{ the other ray ....................... 1 '632 

White topaz ...................................... l'10 

the rays ....................... 1'624 

J 

ie 

i ordinary ray 

1 extraordinary ray 

* 1*642 

1*663 

r ordinary ray 

Quartz 

{ extraordinary ray 

1'548 

*..1'558

' 


Eock salt 1-557 

Chalcedony 

Gypsum 

Opal 

1'553 

1 '525 

1-479 

Borax . 1 '475 

Alum 1'457 

Fluor spar 

1*486 

The higher the index of refraction, the more valuable 

appear to be the individual minerals, as may be seen by 

the corundum and topaz. 

Double refraction, whether positive or negative, being 

inherent in the respective mineral substances, forms a very 

important distinctive character, and the following minerals 

are arranged according to this property : 

CRYSTALS WITH ONE AXIS AND NEGATIVE DOUBLE EEFBACTION. 

Iceland spar. 

Dolomite. 

Anatase. 

Tourmaline. 

Carbonate iron. . Kubellite. 

Carbonate zinc. Corundum. 

Meionite. Emerald. 

Somervillite. Phosphate lime. 

Edingtonate. 

Idocrase. 

Wernerite. Mellite. 

Mica. Arseniate copper. 

Phosphate lead. Arseniate " 

Nepheline. 

Eed silver. 

Molybdate 

" 

Dioptase. 

Cinnabar. 

Alum. 

CRYSTALS WITH ONE AXIS AND POSITIVE DOUBLE REFRACTION. 

Zircon. Hydrate magnesia. 

Quartz. 

Eutil. 

Hydroxide iron. Oxahverite. 

'Oxide tin. Calcareous Scheelite. 

Apophyllite. 

Iron. 

It should be observed that the optic axes are not single 

lines, but directions parallel to a line, or innumerable par-


allel lines, passing through every atom of the crystal. It 

is also important to remark that this property divides the 

systems of crystallization into three precise groups, the 

tesseral, with single refraction ; the tetragonal and hexagonal, 

with double refraction, and monoaxial ; the other three 

systems also double, but binaxial. It is therefore of use to 

determine the system to which a mineral belongs, but is 

not of great value as a character for distinguishing species. 

Polarization of Light. Intimately connected with this 

property is that of the polarization of light, which being 

more easily and precisely observable than double refraction, 

is in many cases of higher value as a mineralogical character. 

By this term is meant a peculiar modification which a ray 

of light undergoes, in consequence of which its capability 

of being transmitted or reflected towards particular sides 

is either wholly or partially destroyed. Thus, if from a 

transparent prism of tourmaline two thin plates are cut 

parallel to its axis, they will transmit light, as well as the 

prism itself, when" they are placed above each other with 

the chief axis of both in the same direction. But when 

the one slip of tourmaline is turned at right angles to the 

other, either no light at all or very little is transmitted, and 

the plates consequently appear black. Hence, in passing 

through the first slip the rays of light have acquired a pe- 

culiar property, which renders them incapable of being 

transmitted through th*e second, except in a parallel posi- 

tion, and they are then said to be polarized. 

The same 

property is acquired by a ray of light when reflected, at 

an angle of 35^ (or angle of incidence 54^), from a plate 

of glass, one side of which is blackened, or from some 

other non-metallic body. When such a ray falls on a 

second similar mirror at an equal angle, but so that the 

plane of reflection in the second is at right angles to that 

in the first, it is no longer reflected, but wholly absorbed.


When, on the other hand, the planes of reflection are 

parallel, the ray is wholly and at any intermediate angle 

partially reflected. A ray of light polarized by reflection 

is also incapable of transmission through a tourmaline slip 

in one position, which, however, is' at right angles to that 

in which a ray polarized by passing through another slip 

is not transmitted. 

In order to observe the polarization of light, a very sim- 

ple instrument will 

be found useful (fig. 

96). At one end of 

a horizontal board 

B a black mirror a 

is fixed. In the 

middle is a pillar 

to which a tube c d 

is fastened, with its 

axis directed to the 

mirror at an angle 

of 35. On the 

lower end is a cover c, with a small hole in the centre, and 

at the upper end another cover with a small black mirror 

m attached to it by two arms, as in the figure, and also at 

an angle of 35 . With this instrument the mirror m can 

be so placed in relation to a that the planes of reflection 

shall have any desirable inclination to exhibit the simple 

polarization of light. 

Fig. 96. 

. This instrument furnishes a simple test whether minerals 

that cleave readily into, thin lamella? are optically mono- 

axial or binaxial. Place the two mirrors with their, polarization-planes 

at right angles, and fix a plate of the mineral 

with a little wax over the hole c, and then observe what 

takes place in the second mirror during the time that the 

cover c is turned round. If the mineral belongs to the bi


naxial system, the light from the first mirror , in passing 

through it, is doubly refracted and has its polarization 

changed, and consequently can be again reflected from the 

second mirror m, and in each revolution of.c will show four 

maxima and four minima of 

intensity. If, on the contrary, 

the mineral is monoaxial,\the 

ray will pass through the lamina 

unaltered, and will not be 

reflected from the second mir- 

ror in any position of c. 

Another beautiful phenom- 

enon of polarized light, in like 

manner connected with the 

crystalline structure of minerals, 

is the colored rings which 

Fig. 98. Fig. 99. 

laminse of the doubly-refracting species, when of a proper 

th ckness, exhibit in certain positions. These rings are


easily seen in the above apparatus by interposing a thir: 

plate of gypsum or mica between the two mirrors. When 

the interposed plate belongs to a monoaxial mineral, there 

is seen in the second mirror a system of circular concentric 

colored rings intersected by a black cross (fig. 97). If the 

mineral is binaxial, one or two systems of elliptical colored 

rings appear, each intersected by a black stripe (fig. 98). 

In certain cases this stripe is curved, or the two systems of 

rings unite in a lemniscoidal form (fig. 99). When the 

planes of polarization are parallel, the 

black cross and stripe appear white 

.(fig. 100), showing 

that in this direc- 

tion the crystals act like singly-refract- 

ing minerals. Quartz, again, in close 

relation to its system of 'crystalliza- 

tion, exhibits a Circular polarization 

of splendid prismatic colors, which, 

on turning the plate, change in each 

point in the order of the spectrum, 

from red to yellow, green, and blue. In order to produce 

these changes, however, in some specimens the plate must- 

be turned to the right, in others to the left, showing a dif- 

ference in the Crystalline structure. 

Pleochroism. Closely connected with double refraction 

is that property of transparent minerals named pleochroism 

(many-colored), in consequence of which they exhibit dis- 

tinct colors when viewed by transmitted light in different 

directions. Crystals of the tesseral system 

do not show 

this property ; while in those of the other systems it ap- 

pears in more or less perfection ; 

and in the tetragonal and 

hexagonal minerals as dichroism (two colors), in the rhombic 

and clinohedric systems as trichroism (three colors). 

In most cases these changes of color are not very decided, 

and appear rather as different tints or shades than as dis-

PHYSICAL PKOPERTIKS OF MINERALS. 9c 

tinct colors. The most remarkable of dichromatic minerals 

are the magnesian mica from Vesuvius, the tourmaline and 

ripidolite ; of trichromatic, the iolite, the andalusite from 

Brazil, the diaspore from Schemnitz, and the axinite. 

Change of Colors Changing Colors Iridescence. 

Some crystalline minerals exhibit a very lively play or 

change of colors from reflected light in certain Directions. 

It is well seen in many various hues on the cleavage-planes 

of Labrador felspar, and seems produced by a multitude of 

very thin quadrangular pores, interposed in the mineral 

like minute parallel lamina?. On the cleavage-planes of the 

hypersthene it appears copper-red, and is occasioned by 

numerous small brown or black laminae of some foreign 

O 

substance interposed in a parallel position between -the 

planes of the hypersthene. The chatoyant, or changing 

colors of the sun-stone, arise from scales of iron-glance simi- 

larly interposed. The play of color in the noble opal seems 

to be produced very nearly in the same manner with that 

in the labradorite. A similar opalescence is seen in certain 

minerals when cut in particular forms. In the" sapphire, 

cut hemispherically over the chief axis, it appears like a 

star with six rays ; in certain varieties of chrysoberyl and 

adularia it has a bluish tint ; 

and is also very remarkable in 

the cat's-eye variety of quartz. Iridescence often arises 

from very fine fissures, producing semicircular arches of 

prismatic tints, which, like the colors of thin plates in gen- 

eral, are referred to the interference of light. 

Lustre and Color. 

: 

"^ ;' 

" 

* . 

Though these properties admit of no precise or mathematical 

determination, they are of considerable value in


mineralogy. One highly important distinction founded on 

them is that of minerals of metallic and non-metallrc aspect 

or character. This distinction can hardly be described in 

words, and the student will best learn to distinguish metallic 

colors and lustre from non-metallic by observing them 

in nature. Transparency and opacity nearly coincide with 

this division, the metallic minerals being almost constantly 

opaque ; the non-metallic more or less transparent. Min- 

erals which are perfectly opaque, and show metallic color 

and lustre, are named metallic; those with only two of 

and those 

these three properties, semi-metallic or metalloid ; 

with the opposite properties non-metallic. 

I/ustre has reference to the intensity and quality of the 

reflected light, considered as 'distinct from color. Several 

degrees in intensity have been named, (l.) Splendent, 

when a mineral reflects light so perfectly as to be visible at 

a great distance, and lively, well-defined images are formed 

in its faces, as galena, rock-crystal, or calc-spar. (2.) 

Shining, when the reflected light is weak, and only forms 

indistinct and cloudy images, as heavy spar. (3.) Glisten- 

ing, when the reflected light is so feeble as not to be observable 

at a greater distance than arm's length, and the- 

surface can no longer form an image. (4.) Glimmering, 

when the mineral held near the eye in full clear daylight 

presents only a number of small shining points, as red 

haematite and granular limestone. When, as in chalk, the 

lustre is so feeble as to be indiscernible, it is said to be dull. 

In regard to the kind or quality of the lustre, the follow- 

ing varieties are distinguished: (1.) The metallic, seen in 

much perfection in native metals and their compounds with 

sulphur, and imperfectly in glance coal. (2.) Adamantine, 

found in beautiful perfection in the diamond, and in some 

varieties of blende and carbonate of lead. (3.) 

Vitreous or 

glassy, seen in rock-crystal or common glass, or inclining

PHYSICAL PROPERTIES OP MTJTERALS. 95 

to adamantine in flint-glass. (4..) Resinous, when the body 

appears as if smeared with oil, as in pitch-stone and garnet. 

(5.) Pearly, like mother-of-pearl, seen in stilbite, gypsum, 

mica. (6.) Silky, the glimmering lustre seen on fine fibrous 

aggregates like amianthus. 

Color. This property is not in all cases of equal value 

as a character. Thus some minerals are naturally colored, 

showing 

in all modes of their occurrence one determinate 

color, which is therefore essential, and forms a characteristic 

of the species. This class includes the metals, pyrites, 

blendes, with many metallic oxides and salts. A second 

class of minerals are colorless, their purest forms being 

white, or clear like water, as ice, calc-spar, quartz, adularia, 

and many silicates. But these minerals are occasionally 

colored that is, accidentally tinged, sometimes from the 

chemical or mechanical admixture of some coloring sub- 

stance, as a metallic oxide, carbon, or particles of colored 

at other times from the substitution of a colored 

minerals ; 

for an uncolored isomorphous element. The colors of these 

minerals therefore vary indefinitely, and can never charac- 

terize the species, but only its varieties. Thus, quartz, 

calc-spar, fluor spar, gypsum, and felspar are often colored 

and horn- 

accidentally by pigments mechanically mixed ; 

blende, augite, garnet, and other colorless silicates, acquire 

green, brown, red, or black tints from the introduction of 

the isomorphic coloring elements. 

"Werner, who bestowed much attention on this portion 

of mineralogy, distinguished eight principal colors, white, 

gray, black, blue, green, yellow, red, and brown, each 

with several varieties or shades arising from intermixture 

with the other colors. He also divided them into metallic 

and non-metallic as follows :


METALLIC COLORS. 

1. White. (1.) Silver-white, as in Icucopyrite and native silver. (2.) 

Tin-white'; native antimony. 

2. .Gray. (1.) Lead-gray; galena or lead glance. (2.) Steel-gray; na- 

tive platina. 

8. Black. (1.) Iron-black; magnetite. 

4. Yellow. (1.) Brass-yellow; chalcopyrite. (2.) Bronze-yellow; iron 

pyrites. (3.) Gold-yellqw ; native gold. 

5. Red. (1.) Copper-red; native copper and nickeline. 

NON-METALLIC COLORS. 

1. White. (1.) Snow-white ; new-fallen snow, Carrara marble, and 

common quartz. (2.) Eeddish-white ; heavy spar. (3.) Yellowish-white; 

chalk. (4.) Grayish-white ; quartz. (5.) Greenish-white ; amianthus. 

(0.) Milk-white; skimmed milk, chalcedony. 

2. Gray. (1.) Bluish-gray; limestone. (2.) Pearl-gray; porcelain jas- 

per, and rarely quartz.. (3.) Smoke-gray or brownish-gray; dense smoke, 

dark varieties of flint. (4.) Greenish-gray; clay-slate and-whet-slate. (5.) 

Yellowish-gray; chalcedony. (6.) Ash-gray; wood-ashes, zoisite, zircon, 

and slate-clay. 

3. Slack. (1.) Grayish-black; basalt, Lydia'n stone, and lucullite.. (2.) 

Velvet-black; obsidian and schorl. (3.) Pitch-black or brownish-black; 

cobalt ochre, bituminous coal, and some varieties of mica. (4.) Greenish- 

black or raven- black; hornblende. (5.) Bluish-black; fluorspar. 

4. Blue. (1.) Blackish-blue; dark varieties of azurite. (2.) Azure-blue; 

bright varieties of azurite and lapis lazuli. (3.) Violet- blue; amethyst 

and fluor spar. (4.) Lavender-blue; lithomarge and porcelain jasper. 

(5.) Plum-blue; spinel and fluor spar. (6.) Berlin-blue; sapphire, rocksalt, 

cyanite. (7.) Smalt-blue ; pale-colored smalt, gypsum. (8.) Duckblue 

talc and corundum. ; (9.) Indigo-blue ; earthy-blue iron or vivianite. 

(10.) Sky-blue ; liroconite, some varieties of fluor spar and of blue spar. 

5. Green. (1.) Verdigris-green; amazon stone and liroconite. (2.) Cel- 

andine-green; green earth, Siberian and Brazilian beryl. (3.) Mountain- 

green; beryl, aqua-marine topaz. (4.) Leek-green; common actynolite 

and prase. (5.) Emerald-green; emerald, and some varieties of green 

malachite. (6.) Apple-green; chrysoprase. (7.) Grass-green; uranite, 

pmaragdite, (8.) Blackish-green; augite and precious serpentine. (9.) 

Pistachio-green; chrysolite and epidote. (10.) Asparagus-green; the 

apatite or asparagus-stone from Spain and Salzburg. (11.) Olive-green ; 

garnet, pitch-stone, and olivine. (12.) Oil-green; olive-oil, blende, beryl. 

(13.) Siskin-green; uranite, and some varieties of pyromorphite. 

6. Yellow. (1.) Sulphur-yellow; native sulphur. (2.) Straw-yellow;


pycnite and karpholite. (3.) "Wax-yellow; opal and wulfenite. (4.) Hon- 

ey-yellow; dark honey, fluor spar, and beryl. (5.) Lemon-yellow; rind 

of ripe lemons, orpiment. (6.) Ochre-yellow; yellow-earth and jasper. 

(7.) Wine-yellow ; Saxon and Brazilian topaz and fluor spar. (8.) Cream- 

yellow or Isabella-yellow ; bole from Strigau, and compact limestone. (9.) 

Orange-yellow, rind of the ripe orange, uran-ochre, and some varieties of 

wulfenite. 

7. Red. (1.) Aurora, or morning-red ; realgar. (2.) Hyacinth-red; hya- 

cinth or zircon, and garnet. (3.) Tile-red ; fresh-burned bricks, porcelainjasper, 

and heulandite. (.4.) Scarlet-red; light-red cinnabar. (5.) Blood- 

red; blood, pyrope. (6.) Flesh-red; felspar and barytes. (7.) Carmine- 

red; carmine, spinel, particularly in thin splinters. (8.) Cochineal-red; 

cinnabar and certain garnets. (9.) Crimson-red ; . oriental ruby and eryth- 

rine. (10.) Cclumbine-red ; precious garnet. (11.) Rose-red; diallogite 

and rose-quartz. (12.) Peach-blossom red ; blossoms of the peach, red 

cobalt-ochre. (13.) Cherry-red; spinel, kermes, and precious garnet. 

(14.) Brownish-red; reddle and columnar-clay ironstone. 

8. JBrotcn. (1.) Reddish- brown; brown blende from the Hartz, and 

zircon. (2.) Clove-brown ; the clove, rock-crystal, and axinite. (3.) Hairbrown 

; wood-opal and limonite. (4.) Broccoli-brown ; zircon. (5.) 

Chestnut-brown; Egyptian jasper. (6.) Yellowish-brown; iron flint and 

jasper. (7.) Pinchbeck-brown; tarnished pinchbeck, mica. (8.) Woodbrown 

; mountain wood and old rotten wood. (9.) Liver-brown ; boiled 

liver, common jasper. (10.) Blackish-brown ; mineral pitch and brown 

coal. 

The accidentally-colored minerals sometimes present two 

or more colors or tints, even on a single, crystal; very re- 

markable examples occurring in fluor spar, apatite, sapphire, 

This is still more com- 

amethyst, tourmaline, and cyanite. 

mon in compound minerals, on which the colors are va- 

riously arranged in points, streaks, clouds, veins, stripes, 

bands, 

or in brecciated and ruin-like forms. . Some miner- 

als again change their color from exposure to the light, 

the air, or damp. Sometimes merely the surface is affected 

or tarnished, and then appears covered as with a thin film, 

producing in some minerals, as silver, arsenic, bismuth, only 

one color ; in others, as copper pyrites, hematite, stibine, 

and common coal, various or iridescent hues. Occasionally 

the change pervades the whole mineral, the color some- 

V" 5

98 A POPULAR TEEATISE ON GEMS. 

times becoming paler, or disappearing, as in ehrysoprase 

and rose-quartz ; at other times darker, as in brown spar, 

siderite, and rhodonite. In a few minerals a complete 

change of color takes place, as in the chlorophaeite of the 

Western Isles, which, on exposure for a few hours, passes 

from a transparent yellow-gre'en to black. These mutations 

seem generally connected with some chemical change. The 

tarnished colors sometimes only appear on certain faces of 

a crystal belonging to a peculiar form. Thus a crystal of 

copper pyrites (like fig. 35) has one face P' free from tar- 

nish ; the faces b and c, close to P', are dark blue ; the re- 

mainder of c, first violet, and then, close to P, gold-yellow. 

The color of the powder formed when a mineral is scratched 

by a hard body 

is often *different from that of the solid 

mass. This is named the streak, and is very characteristic 

of many minerals. It also often shows a peculiar lustre 

where the mineral is soft, as in talc and steatite. 

Phosphorescence, Electricity, Magnetism. 

Phosphorescence is the property possessed by particular 

minerals of producing light in certain circumstances with- 

out combustion or ignition. Thus some minerals appear 

luminous when taken into the dark after being for a time 

exposed to the sun's rays, or even to the ordinary daylight. 

Many diamonds and calcined barytes exhibit this property 

in a remarkable degree ; less so, arragonite, calc-spar, and 

chalk ; 

and in a still inferior degree, rock-salt, fibrous gyp- 

sum, and fluor spar. Many minerals, including the greater 

part of those thus rendered -phosphorescent by the influence 

of the sun, also become so through heat. Thus some 

topazes, diamonds, and varieties of fluor spar, become luminous 

by the heat of the hand ; other varieties of fluor spar 

and the phosphorite require a temperature near that of boil-

PHYSICAL PEOPEETIES OF ]Sn> T ERALS. 99 

ing water; while calc-spar and many silicates are only 

phosphorescent at from 400 to 700 Fahr. Electricity 

produces it in some minerals, as in green fluor spar and 

calcined barytes. In others it is excited when they are 

struck, rubbed, split, or broken ; as many 

varieties of zinc- 

blende and dolomite when scratched with a quill, pieces of 

quartz when rubbed on each other, and plates of mica when 

suddenly separated. 

Friction, pressure, and heat also excite electricity in 

minerals. To observe this property; delicate electroscopes 

are required, formed of a light needle, terminating at both 

ends in small balls, and suspended horizontally on a steel 

pivot by an agate cup. Such an instrument can be nega- 

tively electrified by touching it with a stick of sealing-wax, 

excited by rubbing, or positively when the wax is only 

brought so nêar as to attract the needle. When the instrument 

is in this state the mineral, if also rendered elec- 

tric by heat or friction, will attract or repel the needle ac- 

cording as it has acquired electricity of an opposite or 

similar kind ; but if the mineral is not electric, it will at- 

tract the needle in both conditions alike. Most precious 

stones become electrical from friction, and are either positive 

or negative according as their surface is smooth or 

rough. Pressure even between the fingers will excite dis- 

tinct positive electricity in pieces of transparent double- 

refracting calc-spar. Topaz, arragonite, fluor spar, carbonate 

of lead, quartz, and other minerals show this 

property. 

Heat or change of temperature excites electricity in many 

crystals, as in tourmaline, calamine, topaz, calc-spar, beryl, 

barytes, fluor spar, diamond, garnet, and others, which are 

hence said to be thermo or pyroelectric. Some acquire 

polar pyro-electricity, or the two electricities appear in opposite 

parts of the crystal, which are named, its electric


poles. Each pole is alternately positive and negative, the 

one when the mineral is heating, the other when it is cool- 

ing. The poles that become positive during an increase of 

temperature are named analogue ; those that become negative 

in the same condition, antilogue poles, as shown in this 

table : 

As already noticed, many polar electric minerals are also 

remarkable for their hemimorphic crystal forms. The num- 

ber and distribution of the poles likewise vary. In many 

monoaxial minerals, as tourmaline and calamine, there are 

only two poles, one at each end of the chief aîs ; 

whereas 

boracite has eight poles corresponding to the angles of the 

cube. In prehnite and- topaz, again, two antilogue poles 

occur on the obtuse lateral edges of the prism ooP, and 

one analogue pole corresponding to the macrodiagonal 

chief section, or in the middle of the diagonal joining the 

obtuse edges. The power of retaining the electricity ac- 

quired by rubbing, for a longer time, varies in different 

minerals and gems ; and as the latter are all electric, this 

property may sometimes be used as a distinguishing character 

as to the length of retaining the electricity. Abbe 

Haily found, in his experiments, that many precious stones 

lose their electric power after a few moments, whereas some 

will retain the same for twenty-four hours longer. The 

Brazilian topaz affected the needle, even after thirty-two 

hours. 

Magnetism, or the power to act on the magnetic needle, 

is very characteristic of the few minerals in which it occurs, 

chiefly ores of iron or nickel. It is either simple, attracting


both 'poles of the needle ; 

or polar, when one part attracts, 

and another repels the same pole. Some magnetic iron 

ores, or natural magnets, possess polar magnetism ; while 

the common varieties, meteoric iron, magnetic pyrites, 

precious garnet, and other minerals, are simply magnetic. 

Most minerals 'are only attracted by the magnet, but do 

not themselves attract iron. 

Smell, taste,. and. touch furnish a few characters of min- 

erals. Most have no smell, but some give out a peculiar 

odor when rubbed : as quartz, an empyreumatic- odor, or 

smell of burning ; fluor spar, of chlorine ; clay, of clay ; 

some limestones and marls, of bitumen, or a fetid odor. 

Aluminous minerals acquire a smell when breathed on. 

Other odors caused by heat, and often highly character- 

istic, are noticed under tests by the blo\vpipe. 

Taste is produced by all the salts soluble in water. 

Some are saline, like common salt ; sweetish astringent, 

like alum ; astringent like blue vitriol ; bitter, like epsom 

salts; cooling, like saltpetre; pungent, like sal-ammoniac; 

acid or sour, like sassoline, &c. 

alkaline, like soda ; 

Touch. Some minerals are distinguished by a greasy 

feeling, like talc ; others feel meagre, like clay others cold. 

; 

The last character readily distinguishes true gems from 

their imitations in glass..


CHAPTER III. 

CHEMICAL PROPERTIES OF MINERALS. 

THE consideration of the chemical nature of minerals, 

that is, of the elements that enter into their composition, 

of the manner in which these elements combine, and the 

variations in proportion which they may undergo without 

destroying the.identity of the species, forms an important 

branch of mineralogical science. The. methods of detect- 

ing the different elements, and the characters which are 

thus furnished for the discrimination of minerals, are also 

of much value. This is especially true of the metallic ores 

and other .substances, sought not as objects of curiosity, 

but for their economic qualities. 

Composition of Minerals. 

At present about sixty elements, or substances which 

have not been decomposed, are known. These are divided 

into metallic and non-metallic, a distinction of importance 

in mineralogy, though not always to be carried out with 

precision. The non-metallic elements are rarely of semimetallic 

aspect, and are bad conductors of heat and elec- 

tricity. Some are commonly gaseous oxygen, hydrogen, 

nitrogen, chlorine, and fluorine ; one fluid bromine ; the 

others solid carbon, phosphorus, 'sulphur, boron, selenium, 

and iodine. The metallic elements are, except mercury, 

solid at usual temperatures, have generally a metallic aspect, 

and are good conductors of heat and electricity. They are 

divided into light and heavy metals, the former with a

CHEMICAL PROPERTIES OF MINERALS. 103 

specific gravity under 5, and a great affinity for oxygen, 

and again distinguished as either alkali-metals, potassium 

(or kalium), sodium (or natrium), lithium, barium, stron- 

tium, and calcium ; 

or earth-metals, magnesium, lanthani- 

um, yttrium, glucinum, aluminium, zirconium, silicium. 

The heavy metals, with a specific gravity above 5, are 

divided into noble, which can be reduced or separated, from- 

oxygen, by heat alone ; and ignoble, whose affinity for 

oxygen renders them irreducible without other agents. 

Some of the latter are brittle and difficultly fusible, tho- 

rium, titanium, tantalium (columbium), tungsten (wolframium), 

molybdenum, vanadium, chromium, uranium, manganese, 

and cerium ; others are brittle and easily fusible or 

volatile arsenic, antimony, tellurium, and bismuth; and 

others malleable zinc, cadmium, tin, lead, iron, cobalt, 

nickel, and copper. The noble metals are, quicksilver, 

silver, gold, platinum, palladium, rhodium, iridium, and 

osmium. 

All the chemical combinations observed in the mineral 

kingdom follow the law of definite proportions; that is, 

two elements always combine either in the same proportion, 

or so that the quantity of the one is multiplied by two, 

three, four, or some other definite number seldom very 

large. As the same law prevails throughout the whole 

range of elements, by assuming any one, usually hydrogen 

or oxygen, as unity or 1, and determining froqfc experiment 

the simple proportion in which the others combine with it, 

a series of numbers is obtained which als"o expresses the 

proportions in which all these elements combine 

with each 

other. These numbers, therefore, mark the combining 

proportions or equivalents, as they are named, of the elements. 

They are also named atomic weights, on the sup- 

position that matter consists of definite atoms, and that its 

combinations consist of one atom (or sometimes two atoms)


of one substance, with one, two, three, or more atoms of 

another. This theory is not free from difficulties, but the 

language is often convenient. To designate the elements, 

chemists generally employ the first letter or letters of their 

Latin names. These signs also .indicate one atom or 

equivalent of the element. Thus, O means oxygen in the 

proportion of one atom ; H, hydrogen in the same proportion 

; N", an atom of nitrogen ; Na, an equivalent propor- 

tion of natrium or sodium. These signs and the equivalent 

weights are given in the table on next page, in one column 

of which hydrogen is taken as unity, in the other oxygen. 

Thte elements are arranged according to Berzelius, beginning 

with the most electro-positive, and ending with the 

most electro-negative. 

All these elements occur in minerals, but not more than 

twenty are common, and only about twelve abundant. 

They are also very rare in their simple or uncombined state ; 

only 'carbon in the diamond and graphite, sulphur, and 

about a dozen of the native metals, being thus known. 

More frequently minerals consist of two or more elements 

combined in accordance with those laws which prevail in 

inorganic compounds. The most important of these laws 

is that the combinations are binary; that is, that the ele- 

ments unite in pairs, which may again unite either with 

another compound of two, or with a single element. Inor- 

ganic compdtnds also are generally distinguished 

ganic by their greater simplicity. 

from or


TABLE I. 

Elements arranged in Electro- Chemical order. 

The above list includes ammonium, usually considered -a 

compound body, and omits the two new metals, erbium 

.and" terbium. 

The following principles are observed in designating the 

combinations of these elementary 

5- 

substances : For those of


the first order the signs of the two components are conjoined, 

and the number of atoms or equivalents of each ex- 

pressed by a number following the sign like an algebraic 

exponent. Thus, SO, SO 2 

, SO3 , are the combinations of 

one atom sulphur with one, two, and three atoms of oxygen ; 

FeS, FeS 2 

, of one atom of iron with one or two of sulphur. 

But as combinations with oxygen and sulphur are very 

numerous in the mineral kingdom, Berzelius, to whom 

science is indebted for this system of signs, marks the atoms 

of oxygen by dots over the, sign of the other element, and 

those of sulphur by an accent ; the above compounds being 

then designated thus S, S, S, and Fe', Fe". In some cases 

two atoms of a base combine with three or five of oxygen 

or sulphur, as APO 3 Fe , 2 

S 3 

. In such cases Berzelius marks 

the double atom by a line drawn through the sign 

of the 

single atom ; thus, Al is two atoms aluminium with three 

of oxygen, or alumina ; -On, two of copper with one of oxygen, 

or oxide of copper. Where a number is prefixed to the 

sign like a coefficient in algebra, it includes both elements of 

the combination ; thus H is one atom water, 2 H two ; CaC 

is one atom carbonate of lime, 2 CaC two atoms, includ- 

ing, of course, two of calcium, two of carbon, and six of 

oxygen. 

The most common and important binary compounds are 

those with oxygen, contained in the following table, with 

their signs, atomic numbers, and amount of oxygen in 100 

parts. The more electro-negative are named acids, which 

are often soluble in water, and then render blue vegetable 

colors red. The more electro-positive are named oxides or 

bases, and show great affinity or attractive power for the 

former. The most powerful are the alkaline bases, which 

are colorless and soluble in water ; less powerful are the 

earths, also colorless, but insoluble in water :

TABLE II. Binary Compounds with Oxygen. 107


Similar to the compounds of oxygen are those with sul- 

phur, usually named sulphurets, and considered analogous 

to the oxidized bases. A few of more electro-negative 

character, resembling acids, have been distinguished as sulphides. 

Some other compounds have been named haloid 

gaits, and consist of certain electro-negative elements, com- 

bined with electro-positive ones, as bases. 

Many of these combinations occur as independent species 

in the mineral kingdom, especially those with, oxygen and 

sulphur. Thus the most abundant of all minerals, quartz, 

is an oxide, and corundum is of similar nature. Many 

oxides of the heavy metals, as of iron, tin, copper, and anti- 

mony ; and some super-oxides, as of lead and manganese 

(pyrolusite), are very common. Compounds with sulphur 

also abound, either as sulphides, with the character of 

acids, like realgar, orpiment, and stibine ; or as sulphurets, 

resembling bases, like galena, argentite, and pyrite. Less 

frequent are haloid salts, with chlorine and fluorine, as 

common salt and fluor spar; and still rarer those with 

iodine and bromine. On the other hand, metallic alloys, 

or combinations of electro-negative with electro-positive 

metals, are far from uncommon, especially those with 

arsenic, tellurium, or antimony. 

Combinations of these binary compounds with each other 

are still more common, the greater number of minerals 

being composed of an acid and base. By far the greater 

number are oxygen-salts, distinguished by giving to the 

acid the termination ate ; thu-s sulphate of .lead, silicate of 

lime, and in like manner numerous carbonates, phosphates, 

arseniates, aluminates. The sulphur-salts (two metals combined 

with sulphur, and these again combined with each 

other) are next in number, and perform a most important 

part in the mineral kingdom. The hydrates, or combinations 

of an oxide with water, are also common, and much


resemble the oxygen salts, the water sometimes acting as 

an electro-positive, at other times as an electro-negative 

element. Combinations of a higher order are likewise 

common, especially the double salts, or the union of two 

salts into a new body and even these ; again wr ith water, 

as alum and many hydrous silicates. The chemical formulas 

for these compound salts are formed by writing the signs 

of the simple salts with the sign of addition between them : 

thus Ca C-f-'Mg C, i. e., carbonate of lime and carbonate of 

magnesia, or brown spar ; Al Si 3 + K Si 3 

, 

or orthoclase ; 

3 Na F + Al 2 F 3 

,* or cryolite, composed of three compound 

atoms of fluorine and sodium united to one compound atom, 

consisting of three of fluorine and two of aluminium. 

Influence of the Chemical Composition on the External 

Characters of Minerals. 

That the characters of the compound must in some way 

or other depend on those of its component elements, seems, 

as a general proposition, to admit of no doubt. Hence it 

might be supposed possible, from a knowledge of the composition 

of a mineral, to draw conclusions in reference to 

its form and other properties; but practically this. has not 

yet been effected'. The distinction between the mineral- 

izing and mineralizable, or the forming and formed, elements, 

lies at the foundation .of all such inquiries. Certain 

elements hi a compound apparently exert more than an 

equal share of influence in determining its physical prop- 

erties. Thus the more important non-metallic elements, 

as oxygen, sulphur, chlorine, fluorine, are remarkable for 

the influence they exert on the character of the compound. 

The sulphurets, for example, have more similarity among 

themselves than the various compounds of one and the 

same metal with the non-metallic bodies. Still more gen-

110 A PO?ULAK TKEATISE ON GEMS. 

erally it would appear that the electro-negative element in 

the compound is the most influential, or exerts the greatest 

degree of active forming power. After the non-metallic 

elements the brittle, easily fusible metals rank next in 

power; then the ductile ignoble metals; 

then the noble 

metals ; then the brittle, difficultly fusible ; and last of all, 

the metals of the earths and alkalies. 

It is sometimes stated that each particular substance can 

crystallize only in one particular form or series of forms. 

This is, however, only partially true; and sulphur, for in- 

stance, which usually crystallizes in the rhombic system, 

when melted may form monoclinohedric crystals. This 

property is named dimorphism ; and hence the same chemical 

substance may form two, or even more distinct bodies 

or mineral species. Thus carbon in one form is the dia- 

mond, in another graphite ; carbonate of lime appears as 

calc-spar or arragonite ; the bisulphuret of iron, as pyrite 

and marcasite. An example of trimorphism occurs in the 

titanic acid, forming the three distinct species, anatase, 

rutile, and brookite. Even the . temperature at which a 

substance crystallizes -influences its forms, and so far its 

composition, as seen in 'an-agonite, Glauber salt, natron, 

and borax. 

Still more important is the doctrine of isomorphism, des- 

ignating the fact that two or more simple or compound 

substances crystallize in one and the same form ; or often 

in forms which, though not identical, yet approximate very 

closely. This similarity of form is generally combined with 

a similarity in other physical properties. Among minerals 

that crystallize in the tesseral form, isomorphism is of course 

common and perfect, there being no diversity in the dimen- 

sions of the primary form ; but for this very reason it is of 

less interest. It is of more importance among mono-axial 

crystals, the various series of which are separated from each

CHEMICAL PKOPERTIES OF MINERALS. Ill 

other by differences in the proportion of the primary form 

In these, perfect identity is seldom observed, but only very 

great similarity. 

The more important isomorphic substances are the fol- 

lowing : 

I. Simple substances : 

(l.) Fluorine and chlorine. 

(2.) Sulphur and selenium. 

(3.) Arsenic, antimony, tellurium. 

(4.) Cobalt, iron, nickel. 

(5.) Copper, silver, quicksilver, gold (?). 

II. Combinations with oxygen : 

(1.) Of the formula B. 

(a.) Lime, magnesia, protoxide of iron, protoxide 

of manganese, oxide of zinc, oxide of nickel, 

oxide of cobalt, potassa, soda. 

(b.) Lime, baryta, strontia, lead-oxide. 

(2.) Of the formula S. 

(a.) Alumina, peroxide of iron, peroxide of manganese, 

oxide of chromium. 

(b.) Antimony oxide, arsenious acid. 

(3.) Formula R. Tin-oxide, titanium-oxide. 

(4.) Formula R. Phosphoric acid, arsenic acid. 

(5.) 

Formula R. 

(a.) Sulphuric acid,.selenic acid, chromic acid, man- 

ganese acid. 

(b.) Tungstic acid, molybdic acid. 

HI. Combinations with : sulphur 

Formula Rf . Sulphuret of iron Fe', and sulphu- 

(1.) 

ret of zinc Zn'. 

(2.) Formula ft'". Sulphuret ofântimony Sb' 

1 

and 

', 

sulphuret of Arsenic As'". 

(3.) Formula -R'. Sulphuret of copper -0u', and sul- 

phuret of silver Ag'.


These substances are named vicarious, from the singular 

property that in chemical compounds they can mutually 

replace each other in indefinite proportions, and very often 

without producing any important change in the form or 

other physical properties. But there are numerous in- 

stances among the silicates, where the mutual replacement 

of the isomorphic bodies, especially when the oxides of the 

heavy metals come in the room of the earths and alkalies, 

exerts a most essential influence on the external aspect oi 

the species, particularly in regard to color, specific gravity, 

and transparency. The varieties of hornblende, augite, 

garnet, epidote, and many other minerals, are remarkable 

proofs of this influence. This intermixture *of isomorphic 

elements confers many valuable properties on minerals, and 

.to it this department of nature owes much of its variety and 

beauty. Without the occasional presence of the coloring 

substances, especially the oxides . of iron and manganese, 

the non-metallic combinations would have exhibited a very 

monotonous aspect. It is also remarkable, that in some 

silicates the substitution of a certain portion of the metallic 

oxides for the earthy bases seems to be almost a regular 

occurrence; while in others, as the felspars and zeolites, 

this rarely happens. This fact is of very great economic 

importance, as drawing attention to important elements 

often combined with others of less value. Thus iron oxide 

and chrome oxide, sulphuret of copper and sulphuret of 

silver, nickel and cobalt, may be looked for in connection. 

The general chemical formula for such compounds is formed 

by writing R (= radicle or basis) for the whole isomorphic 

elements; and in special instances to place their signs 

either one below the other, connected by a bracket, or, as 

is more convenient, to inclose them in brackets one after 

the other, separated by a comma. Thus the general sign 

for the is garnet R 3 

Si 2+R Si, which, wThen fully expressed.


;-, 

becomes Fe 1 1 Si'+^- [ Si; or(Ca ! 

,Fe 3 

,Mn 3 

)Si'+(Al,e)Si, 

fin'} 

and the mineral forms many varieties, as the one or other 

element predominates. 

Chemical Reaction of Minerals. 

The object pf the chemical examination of minerals is 

the discovery of those elementary substances of which the j 

consist. This examination is named qualitative when the 

nature of the elements alone, quantitative when also their 

relative amount, is sought to be determined. Mineralogists 

are in general content with such an examination as will 

discover the more important elements, and which can be 

carried on with a simple apparatus, and small quantities of 

the substance investigated. The indications thus furnished 

of the true character of the mineral are, however, frequently 

of high importance. Two methods of testing minerals are 

employed, the one by heat chiefly applied through the blowpipe, 

the second by acids and other reagents in solution. 

Use of the Blowpipe- 

The blowpipe in its simplest form is merely a conical 

tube of brass or othei* metal, curved round at the smaller 

extremity, and terminating in a minute circular aperture 

not larger than a fine needle. Other forms have been 

proposed, one of the" most useful being a cone of tin, open 

for the application of the mouth at the smaller end, and 

with a brass or platina beak projecting from the side near 

the other or broad end. With this instrument a stream of 

air is conveyed from the mouth to the flame of a lamp or 

candle, so that this can be turned aside, concentrated, and


directed upon any small object. The flame thus acted on 

consists of two parts the one nearest the beak of the blow- 

pipe forming a blue obscure cone, the other external to this 

being of a shining yellow or reddish-yellow color. The 

blue cone consists of the inflammable gases not yet fully 

incandescent, and the greatest heat is just beyond its point, 

where this is fully effected. The blue flame still needs 

oxygen for its support, and consequently tends to withdraw 

it from any body placed within its influence, and is named 

the reducing flame. At the extremity of the yellow cone, 

on the other hand, the whole gases being consumed and 

the external air having free access, bodies are combined 

with oxygen, and this part is named the oxidating flame. 

Their action being so distinct, it is of great importance for 

the student to learn to distinguish accurately these two 

portions of the flame. This is best done by experimenting 

on a piece of metallic tin, which can only be kept pure in a 

good reducing flame, and acquires a white crust when acted 

on by the oxidating flame. 

The portion of the mineral to be examined should not 

be larger than a peppercorn, or a fine splinter a line or two 

long. 

It is supported in the flame either by a pair of fine 

pincers pointed with platinum, or on slips of platinum-foil, 

or on charcoal. Platinum is best for the siliceous minerals, 

whereas for metallic substances charcoal must be employed. 

For this purpose solid uniform pieces are chosen, and a 

small cavity formed in the surface in which the mineral to 

be tested can be deposited. 

In examining a mineral by heat, 

it should be first tested 

alone, and then with various reagents. When placed alone 

in a matrass or tube of glass closed at one end, and heated 

over a spirit-lamp, water or other volatile ingredients, mer- 

cury, arsenic, tellurium, often sulphur, may readily be de- 

tected, being deposited in the cooler part of the tube, or,


like fluorine, acting on the glass. It may next be tried in 

an open tube of glass, through which a more or less strong 

current of air passes according to the inclination at which 

the tube is held, so that volatile oxides or acids may be 

formed ; 

and in this way the chief combinations of sulphur, 

selenium, tellurium, and arsenic are detected. On char- 

coal, in the reducing flame, arsenic, and in the oxidating 

flame, selenium or sulphur, are shown by their peculiar 

odor ; antimony, zinc, lead, and bismuth leave a mark or 

colored ring on the charcoal ; and other oxides and sul- 

phurets are reduced to the pure metal. On charcoal or in 

the platinum pincers the fusibility of minerals is tested, and 

some other phenomena should be observed as whether 

they intumesce (bubble up), effervesce, give out fumes, become 

shining, or impart a color to the flame. The color is 

seen when the assay is heated at the point of the inner 

flame, and is 

Reddish-yellow, from soda and its'salts ; 9 

Violet, from potash and most of its salts ; 

Red, from litliia, strontia, and lime ; 

Green, from baryta, phosphoric acid, boracic acid, molybdic acid, 

copper oxide, and tellurium oxide ;. 

Blue, from chloride of copper, bromide of copper, selenium, arsenic, 

antimony, and lead. 

The fusibility, or ease with which a mineral is melted, 

should also be observed; and to render this character more 

precise, Yon Kobell has proposed this scale: (l.) Antimony 

glance, which melts readily in the mere candle flame ; 

(2.) Xatrolite, which in fine needles also melts in the candle 

flame, and in large pieces readily before the blowpipe ; (3.) 

Almandine (garnet from Zillerthal), which does not melt 

in the candle flame even in fine splinters, but in large pieces 

before the blowpipe ; (4.) Strahlstein (hornblende from 

Zillerthal) melts with some difficulty, but still more readily 

than (5.) Orthoclase (or adularia felspar) ; and (6.) Bron-


zite or diallage, of which only the finest fibres can be 

rounded by the blowpipe. In employing this scale, fine 

fragments of the test minerals and of that to be tried, and 

nearly of equal size, should be exposed at the same time to 

the flame. A more common mode of expressing fusibility 

is to state whether it is observable in large or small grains, 

in fine splinters, or only on sharp angles. The result or 

product of fusion also yields important characters, being 

sometimes a glass, clear, opaque, or colored ; at other times 

an enamel, or a mere slag. 

The most important reagents for testing minerals with 

the blowpipe are the following: (1.) Soda (the carbonate), 

acting as a flux for quartz and many silicates, and especially 

for reducing the metallic oxides. For the' latter purpose, 

the assay (or mineral to be tried) is reduced to powder, 

kneaded up with moist soda into a small ball, and placed 

in a cavity of the charcoal. Very often both the soda and 

assa^ sink into the charcoal, 'but by continuing the opera- 

tion they either again appear on the surface, or, when it is 

completed, the charcoal containing the mass is finely pounded 

and washed away with water, when the reduced metal is 

found in the bottom of the vessel. (2.) Borax (biborate of 

soda) serves as a flux for many minerals, which are best, 

fused in- small splinters on platina wire. The borax when 

first exposed to the flame swells up or intumesces greatly, 

and it should therefore be first melted into a small bead, in 

which the assay is placed. During the process the student 

should observe whether the assay melts easily or difficultly, 

with or without effervescence, what color it .imparts to the 

product both when warm and when cold, and also the effect 

both of the oxidating and reducing flames. (3.) Microcos- 

mic salt, or salt of phosphorus (phosphate of soda and am- 

monia), is specially important as a test for metallic oxides, 

which exhibit far more decided colors with it than with

CHEMICAL PROPERTIES OP MINERALS. 117 

borax. It is also a useful reagent for many silicates, whose 

silica is separated from the base and feraains undissolved 

in the melted salt. 

(4.) Solution of cobalt (nitrate 

of co- 

balt dissolved in water), or dry oxalate of cobalt, serve as 

tests of alumina, magnesia, and zinc oxide. 

In examining minerals in th*e moist way, the first point 

to be considered is their solubility, of which three .degrees 

may be noted : (!) minerals soluble in water ; (2) minerals 

soluble in hydrochloric or nitric acid; and (3) those un- 

affected by any of these fluids. The minerals soluble in 

water are either acids (almost only the boracic acid or sas- 

solin and the arsenious acid), or oxygen or haloid salts. 

These are easily tested, one part of the solution being em- 

ployed to find the electro-positive element or basis, the 

other the electro-negative or acid. 

Minerals insoluble in water may next be tested with the 

above acids; the nitric acid being preferable when it is 

probable, from the aspect of the mineral or its conduct be- 

fore the blowpipe, that it contains an alloy, a sulphuret, 

or arseniate of some metal. In this manner the carbonic, 

phosphoric, arsenic, and chromic acid salts, many hydrous 

and anhydrous silicates, many sulphurets, arseniates, and 

other metallic compounds, are* dissolved, so that further 

tests may be employed. 

The minerals insoluble either in water or these acids are" 

sulphur, graphite, cinnabar, some metallic oxides, some 

sulphates, and compounds with chlorine and fluorine, and 

especially quartz, and various silicates. For many of these 

no test is required, or those furnished by the blowpipe are 

be fused with four 

sufficient. The silicates and others may 

times their weight of anhydrous carbonate of soda when 

they are rendered soluble, so that further tests may be ap- 

plied.


Chemical Reaction of the, more Important Element*. 

It is not intended in this place to describe the chemical 

nature of the elementary substances, and still less to enu- 

merate the whole of those marks by which the chemist * 

can 

detect their presence. Our object is limited principally to 

the conduct of minerals before the blowpipe, and to a few 

simple tests by which their more imp'ortant constituents 

may be discovered by the student. 

I. NON-METALLIC ELEMENTS, AND THEIR COMBINATIONS 

WITH OXYGEN. 

Nitric Acid. Most of its salts detonate when heated on 

charcoal. In the closed tube they form nitrous acid> easily 

known by its orange color and smell ; a test more clearly 

exhibited when the salt is mixed with copper filings and 

treated with concentrated sulphuric acid. When to the 

solution of a nitrate, a fourth part of sulphuric acid, is added, 

and a fragment of green vitriol placed in it, the surround- 

ing fluid becomes of a dark-brown color. 

tube or on char- 

Sulphur and its compounds, in .the glass 

coal, form sulphurous acid," easily known by its smell. The 

minutest amount of sulphur or sulphuric acid may be detected 

by melting the pulverized assay with two parts soda 

and one part borax, and placing the bead moistened with 

water on a plate of clean silver, which is then stained brown 

or black. Solutions of sulphuric acid give with chloride of 

barium a heavy white precipitate, insoluble in acids. 

Phosphoric 

Acid. Most combinations with this acid 

tinge the blowpipe flame green, especially if previously 

moistened with sulphuric acid. The experiment must be 

performed in the dark,, when even three per cent, of the 

acid may be detected. If the assay is melted with six parts


of soda, digested in water, filtered, and neutralized with 

acetic acid, the solution forms an orange-yellow layer round 

a crystal of nitrate of silver. This solution, with muriate 

of magnesia, forms a white crystalline precipitate. 

Selenium and Setenic Add are readily detected by the 

strong smell of decayed horse-radish, and leave a gray deposit 

with a metallic lustre on the charcoal. 

Chlorine and Hs salts. When oxide of copper is melted 

with salt of phosphorus into a very dark-green bead, and 

an assay containing chlorine fused with this, the flame is 

tinged of a beautiful reddish-blue color, 

till all the chlorine 

is driven off. If very little chlorine is present, the assay is 

dissolved in nitric acid (if not soluble it must first be melted 

with soda on platinum wire), and the diluted solution gives, 

with nitrate of silver, a precipitate of chloride of silver, 

which is first white, but on exposure to the light becomes 

gradually brown, and at length black. 

Iodine and its salts, treated like chlorine, impart a very 

beautiful bright-green color to the flame ; and heated in 

the closed tube with sulphate of potash, yield violet-colored 

vapors. In solution it gives, with nitrate of silver, a pre- 

cipitate similar to chlorine, but which -is very difficultly 

soluble in ammonia. Its surest test is the blue color it im- 

parts to starch, best seen, by pouring concentrated sulphuric 

acid over the mineral in a test tube which has a 

piece of paper or cotton covered with moist starch over its 

mouth. 

Bromine and its salts, treated in the same manner with 

salt of phosphorus and oxide of copper, color the blowpipe 

flame greenish-blue. In the closed tube with nitrate of 

potassa they yield bromine vapors, known by their yellow 

color and peculiar disagreeable smell. Treated with "sul- 

phuric acid, bromine in a few hours colors starch pome- 

granate-yellow.


Fluorine is shown by heating the assay with sulphate of 

potassa, in a closed tube with a .strip of logwood-paper in 

the open end. The paper becomes straw-yellow, and the 

glass is corroded. Another test is to heat the pulverized 

mineral with concentrated sulphuric acid in a shallow dish 

of platinum (or lead), over which a plate of glass covered 

with a coat of wax, through which lines have, been drawn 

with a piece of sharp-pointed wood, is placed. If fluorine 

is present, the glass is etched where exposed. 

JBoracic Acid. The mineral alone, or moistened with 

sulphuric acid, when melting, colors the flame momentarily 

green. If the assay be heated with sulphuric acid, and 

alcohol added and set on fire, the flame is colored green 

from the vapors of the boracic acid. 

Carbon, pulverized and heated with saltpetre, detonates, 

leaving carbonate of potassa. Carbonic acid is not easily 

discovered with the blowpipe, but the minerals containing 

it effervesce in hydrochloric acid, and the colorless gas 

that escapes renders litmus-paper red. In solution it forms 

a precipitate with lime-water, which is again dissolved with 

effervescence in acids. 

Silica, before the blowpipe, alone is unchanged ; is very 

slowly acted on by borax, very little by salt of phosphorus, 

but with soda melts entirely with a brisk effervescence into 

a clear glass. The silicates are decomposed by 

salt of 

phosphorus, the silica being left in the bead as a powder 

or a skeleton. Most of them melt with soda to a trans- 

parent glass. .Some silicates are dissolved in hydrochloric 

acid, and this the more readily the more powerful the 

basis, the less proportion of silica, and the greater the 

amount of water they contain. Sometimes the acid only 

extracts the basis, leaving the silica as a powder or jelly ; 

or the silica too is dissolved, and only gelatinizes on evaporation. 

The insoluble silicates may be first melted with


some carbonate of an alkali*, when the solution gelatinizes, 

and finally leaves a dry residuum, of which the part insolu- 

ble in warm hydrochloric acid has all the properties of 

silica. 

n. THE ALKALIES AXD EARTHS. 

Ammonia, heated with soda in a closed tube, is readily 

known by its smell. Its salts, heated with solution of 

potassa, also yield the vapor, known from its smell, its 

action on turmeric-paper, and the white fumes that rise 

from a glass tube dipped in hydrochloric acid held over it. 

Soda, imparts a reddish-yellow 

color to the external 

flame when the assay is fused or kept at a strong red heat. 

In solution it yields no precipitate with chloride of platinum 

or sulphate of alumina. 

Lithia is best recognized by the beautiful carmine-red 

color it imparts to the flame during the fusion of a mineral 

containing it in considerable amount. Where the proportion 

is small, the color appears if the assay be mixed with 

1 part fluor spar and 1^ parts sulphate of potassa. In 

concentrated solutions it forms a precipitate with the phos- 

phate and carbonate of soda, but none with bichloride 

platinum, sulphate 

ol 

of alumina, or acetic acid. 

Potassa gives a violet color to the external cone,' when 

thâssay is heated at the extremity of the oxidating flame. 

The presence of lithia or soda, however, disturbs this re- 

.action. It may still be discovered by melting the assay in 

borax glass colored brown by nickel ' 

oxide, which is 

changed to blue by the potassa. 

In concentrated solutions 

of potassa, the bichloride of platinum gives a citron-yellow 

precipitate ; acetic acid, a white granular precipitate ; and 

sulphate of alumina, after some time, a deposit 

crystals. 

of alum-' 

Baryta. The carbonate of this earth melts easily to a 

6


clear glass, milk-white when cold; the sulphate is very 

difficultly fusible. Both strongly heated at the point of 

the blue flame impart a green tinge to the outer flame. 

When combined with silica it cannot be well discovered by 

the blowpipe. In solution, salts of baryta yield, with sul- 

phuric acid or solution of sulphate of lime, immediately a 

fine white precipitate insoluble in acids or alkalies. 

Strontia, the carbonate, even in thin plates, only melts 

on the edges, and forms cauliflower-like projections of 

dazzling brightness ; the sulphate melts easily 

in the oxi- 

dating flame, and in the reducing flame is changed into 

sulphuret of strontium, which, dissolved in hydrochloric 

acid, and evaporated to dryness, gives a fine carmine-red 

color to the flame of alcohol. Strontia in solution gives 

a precipitate with sulphuric- acid, or with sulphate of lime, 

but not immediately. 

Lime. The carbonate is rendered caustic by heat, when 

it has alkaline properties, and readily absorbs water. The 

sulphate in the reducing flame changes to the sulphuret 

of calcium, which is also alkaline. Sulphuric acid precipi- 

tates lime only from very concentrated solutions; oxalic 

acid even from very weak ones ; and silico-hydrofluoric acid 

not at all. As baryta and strontia also form precipitates 

with the first two reagents, they must previously be sepa- 

rated by sulphate of potassa. Chloride of calcium tinges 

the flame of alcohol yellowish-red. 

Magnesia, alone, or as a hydrate, a carbonate, and in 

some other combinations, when ignited with solution of 

cobalt, or the oxalate of cobalt, assumes a light-red tint. 

It is not precipitated from a solution either by sulphuric 

acid, oxalic acid, or silico-hydrofluoric acid ; but phosphoric 

acid, with ammonia, throws down a white crystalline pre- 

cipitate of phosphate of ammonia and magnesia. 

Alumina alone is infusible. In many combinations, when

CHEMICAL PBOPERTTES OF MINERALS. 123 

ignited with solution of cobalt, it assumes a fine blue color. 

It is thrown down by potassa or soda as a white volumin- 

ous precipitate, which in excess of the alkali is easily and 

completely soluble, but is again precipitated by muriate of 

ammonia. Carbonate of ammonia also produces a precipi- 

tate which is not soluble in excess. 

Glucina, Yttria, Zirconia, and Thorina are not properly 

distinguished by blowpipe tests, though the minerals 

in which they occur are well marked in this way. In 

solution, glucina acts with potassa like alumina ; but the 

precipitate with carbonate of ammonia . is again soluble, 

with excess of the alkali, and the two earths may thus be 

separated. Yttria is precipitated by potassa, but is not 

again dissolved by excess of the alkali. With carbonate 

of ammonia it acts like glucina. It must be observed, 

however, that the substance formerly named yttria is now 

considered a mixture of this earth with the oxides of er- 

bium, terbium, and lanthanium. Zirconia acts with potassa 

like yttria, and with carbonate of ammonia like glucina. 

Concentrated sulphate of potassa throws down a double salt 

of zirconia and potassa, which is very little soluble in pure 

water. 

III. THE METALS. 

Arsenic and its sulphuret on cha/coal yield fumes, with 

a smell like garlic, and sublime in the closed tube. The 

greater number of alloys- of arsenic in the reducing flame 

leave a white deposit on . the 

charcoal ; or, where it is in 

larger proportion, give out grayish-white fumes with a 

smell of garlic. Some alloys 'also yield 

metallic arsenic in 

the closed tube. In the open tube all of them yield ar.se- 

nious acid, and those containing sulphur also sulphurous 

fumes. Many arsenic acid salts emit evident odors of 

and some sub- 

arsenic when heated on charcoal with soda ;


lime metallic arsenic when heated with pulverized charcoal 

in the closed tube. 

Antimony melts easily on charcoal, emitting dense white 

fumes, and leaving a ring of white crystalline oxide on the 

support. In the closed tube it does not sublime, but burns 

in the open tube with white smoke, leaving a sublimate on 

the glass, which is easily driven from place to place by heat. 

Most of its compounds, with sulphur or "with the other 

metals, show similar reaction. Antimony oxide on charcoal 

melts easily, fumes, and is reduced, coloring the flame 

pale greenish-blue.. 

Bismuth melts easily, fumes, and leaves a yellow oxide 

on the charcoal. In the closed tube it does not sublime, 

and in the open tube scarcely fumes, but is surrounded by 

the fused oxide, dark-brown when warm, and bright-yellow 

when cold. Its oxides are easily reduced. A great addi- 

tion of water produces a white precipitate from its solution 

in nitric acid. . 

Tellurium fumes on charcoal, and becomes surrounded 

by a white mark with a reddish border, which, when the 

reducing flame is turned on it, disappears 

with a bluish- 

green light. In the closed tube tellurium gives a sublimate 

of the gray metal ; and in the open tube produces 

copious fumes, and a white powder which can be melted 

into small clear drops. . 

Mercury in all its combinations is volatile, and yields a 

metallic sublimate when heated alone, or with tin or soda 

in the closed tube. 

Zinc, when heated with soda on charcoal, forms a de- 

posit, which> when warm, is yellow; when cold, white ; 

tinged of a fine green by solution of cobalt, and is not further 

volatile in the oxidating flame. In solution, zinc is 

precipitated by potassa as a white gelatinous hydrate, easily 

redissolved in the excess of the alkali. 

is


Tin forms a white deposit on the charcoal behind the 

assay, which takes a bluish-green color with the solution oi 

cobalt. The oxide is easily reduced by soda. 

-LeadTorms a sulphur-yellow deposit with a white border 

on the charcoal when heated in the oxidating flame, and 

with soda is easily reduced. The solutions of its salts are 

colorless, but give a black precipitate with sulphuretted 

with sulphuric acid a white, and with chromate 

hydrogen ; 

of potassa a yellow, precipitate. 

Cadmium produces, with soda, a reddish-brown or 

orange-yellow ring, with iridescent border on the charcoal, 

and also on platinum-foil. 

Manganese alone, melted with borax or salt of phosphorus 

on the platinum wire in the oxidating flame, forms 

a fine amethystine glass, which becomes colorless in the 

reducing flame. In combination with other metals, the 

pulverized assay mixed with two or three times as much 

soda, and melted in the oxidating flame on platinum-foil, 

forms a bluish-green glass. Potassa or ammonia throws 

down from solutions of its salts a white hydrate, which, in 

the air, becomes gradually dark-brown. 

Cobalt, melted with borax in the oxidating flame, gives 

a beautiful blue glass. Minerals of metallic aspect must be 

first roasted on charcoal. The salts of protoxide of cobalt 

form bright-red solutions, from which potassa throws down 

a blue flaky hydrate, which becomes olive-green hi the air. 

tube and on 

Nickel, the assay, first roasted in the open 

charcoal, produces in the oxidating flame, with borax, a 

glass, which hot, is reddish or violet brown ; when cold, 

yellowish or dark red ; and by the addition of saltpetre, 

changes" to blue. In the reducing flame the glass appears 

gray. With salt of phosphorus the reaction is similar, but 

the glass is almost colorless when cold. The salts in solu- 

tion have a bright-green color, and with potassa, form a


green precipitate of liydrated nickel-oxide, which is un- 

changed in the air. 

Copper may in most cases be discovered by melting 

the assay (if apparently metallic, first roasted) wifh borax 

or salt of phosphorus in the oxidating flame, when an 

opaque recldish-brown glass is produced, a small addition 

of tin aiding in the result. In the reducing flame, the glass, 

when warm, is green ; when cold, blue. With soda, me- 

tallic copper is produced. A small proportion of copper 

may often be detected" by heating the assay, moistened 

with hydrochloric acid, in the oxidating flame, which is 

then tinged of a beautiful green color. Solutions of its 

salts are blue or green, and produce a brownisliTblack pre- 

cipitate, with sulphuretted hydrogen. Ammonia at first 

throws down a pale-green or blue precipitate, but in excess 

produces a very fine blue color. t 

Silver in the metallic state is at once known, and from 

many combinations can be readily 

extracted on charcoal 

with soda. From its solution in nitric acid, silver is thrown 

down by hydrochloric acid as a white chloride, which in 

the light soon becomes black, is" soluble in ammonia, and 

can again be precipitated from this solution by nitric acid 

as chloride of silver. 

Gold, when pure, is readily known, and is easily separated 

'from its combinations with tellurium on charcoal. If the 

and must 

grain is white, it contains more silver than gold, 

then be heated in a porcelain capsule with nitric acid, which 

gives it a Wack color, and gradually removes the silver, if 

the gold is only a fourth part or less. If the proportion of 

gold is greater, the nitro-chloric acid must be used, which 

then removes the gold. From its solution in this acid the 

protochloride of tin throws down a purple precipitate (pur- 

ple of Cassius), and the sulphate of iron, metallic gold. 

Platinum, and the metals usually found with it, cannot


be separated from each other by heat. Only the Osmium- 

iridium strongly heated in the closed tube with saltpetre 

is decomposed, forming osmium acid, known from its pecu- 

liar pungent odor. The usual mixture of platinum grains 

is soluble in nitro-chloric acid, leaving osmium-iridium. 

From this solution' the platinum is thrown down by salammonia 

as a double chloride of platinum and ammonium. 

From the solution evaporated, and again diluted, with 

cyanide of mercury, the palladium separates as cyanide of 

palladium. The rhodium may be separated by its property 

of combining with fused bisulphate of potassa, which is not 

the case with platinum or iridium. 

Cerium, when no iron-oxide is present, produces, with 

borax and salt of phosphorus, in the oxidating flame, a red 

or dark-yellow glass, which becomes very pale when cold, 

and colorless in the reducing flame. Lanthanium oxide 

forms a white colorless glass ; didymium, a dark amethyst- 

ine glass. 

Iron, the peroxide and hydrated peroxide, become black 

and magnetic before the blowpipe, and form, with borax or 

salt of phosphorus, in the oxidating flame, a dark-red glass, 

becoming bright-yellow when cold and in the ; 

reducing 

flame, especially on adding tin, an olive-green or mountaingreen 

glass. The peroxide colors a bead of borax contain- 

the protoxide produces red 

ing copper oxide, bluish-green ; 

spots. Salts of protoxide of iron form a green solution, 

from which potassa or ammonia throws down the protoxide 

as a hydrate, which is first white, then dirty-green, and 

finally yellowish-brown. Carbonate of lime produces no 

precipitate. The salts of the peroxide, on the other hand, 

form yellow solutions from which the peroxide is thrown 

down by potassa or ammonia as a flaky-brown hydrate. 

Carbonate of lime also causes a precipitate. 

Chromium forms, with borax or salt of phosphorus, a


glass, fine emerald-green when cold, though when hot often 

yellowish or reddish. Its solutions are usually green, and 

the metal is thrown down by potassa as a bluish-green hy - 

drate, again dissolved in excess of the alkali. The chrome 

in many minerals is very certainly discovered by melting 

the assay with three times its bulk of saltpetre, which, dis- 

solved in water, gives with acetate oflead a yellow precipitate. 

Vanadium, melted on platinum wire with borax or salt 

of phosphorus, gives a fine green glass 

in the reducing 

flame, which becomes yellow or brown in the oxidating 

flame, distinguishing it from chrome. 

Uranium, with salt of phosphorus, forms in the oxidating 

flame a clear yellow ; in the reducing flame a fine green 

glass. With borax its reaction is similar to that of iron. 

Molybdenum forms in the reducing flame, with salt of 

phosphorus, a green ; with borax, a brown, glass. . 

Tungsten or Wolfram forms, with salt of phosphorus, in 

the oxidating flume, a colorless or yellow, in the reducing 

flame, a very beautiful blue glass, which appears green 

when warm. AYhen accompanied by iron, the glass is bloodred, 

not blue. Or melt the assay with five times as much 

soda in a platinum spoon, dissolve it in water, filter, and 

decompose the result with hydrochloric acid, which throws 

down the tungstic acid, which is white when cold, but 

citron-yellow when heated. 

Tantalium, as tantalic acid, is readily dissolved by salt 

of phosphorus, and in large quantity into a colorless glass, 

which does not become opaque in cooling, and does not 

acquire a blue color from solution of cobalt. Or fuse the 

assay with two times as much saltpetre, and three times as 

much soda, in a platinum spoon ; dissolve this, filter, and 

decompose the fluid by hydrochloric 

acid : 

the tantalic acid 

separates as a white powder, which does not become yellow 

when heated.

CLASSIFICATION OF MINERALS. 129 

Titanium in anatase, rutile, brookite, and titanite, is 

shown by the assay forming, with salt of phosphorus, in 

the oxidating flame, a glass which is and remains colorless ; 

in the reducing flame, a glass which appears yellow when 

hot, and whilst cooling passes through red into a beautiful 

vi^fet. When iron is present, however, the glass is blood- 

red, but is changed to violet by adding tin. When titanate 

of iron is dissolved in hydrochloric acid, and the solution 

boiled with a little tin, it acquires a violet color from the 

oxide of titanium. Heated with concentrated sulphuric 

acid, the titanate of iron produces a blue color. 

CHAPTER IV. 

CLASSIFICATION OF MINERALS. 

A MINERAL species was formerly defined as a natural in- 

organic body, possessing a definite chemical composition 

and peculiar external form. The account given of these 

properties shows that the form of a mineral species comprehends 

not only the primary or fundamental figure, but 

all those that may be derived from it by the laws of crystallography. 

Irregularities of form arising from accidental 

causes, or that absence "of form which results from the 

limited space in which the mineral has been produced, do 

not destroy the identity of the speeies. 

Even amorphous 

masses, when the chemical composition remains unaltered, 

are properly classed under the same species, as the perfect 

crystal. 

The definite chemical composition of mineral species 

must be taken with equal latitude. Pure substances, such 

as they are described in works on chemistry, are very rare


in the mineral kingdom. In the most transparent quartz 

crystals, traces of alumina and iron oxide can be detected ; 

the purest spinel contains a small amount of silica, and the 

most ^brilliant diamond, consumed by the solar rays, leaves 

some ash behind. Such non-essential mixtures must be 

neglected, or each individual crystal would form a distiiHt 

mineral species. The isomorphous elements introduce a 

wider range of varieties, and render the limitation of species 

' 

more difficult. Carbonate of lime, for instance, becomes 

mixed with carbonate of magnesia or of iron in almost 

innumerable proportions; and the latter substances also 

with the former. Where these mixtures are small in amount, 

variable in different specimens, and do not greatly affect 

the form or physical characters of the predominant element, 

they may safely be neglected, and the mineral. reckoned to 

that species with which it most closely agrees. "Where, 

and the two substances 

however, the mixture is greater, 

are frequently found in definite chemical proportions, these 

compounds must be considered as distinct species, espe- 

cially should they also show differences in form and other 

external characters. 

Amorphous minerals with definite composition must also 

be considered as true species. But when they show no 

definite composition, as in many substances classed as clays 

and ochres, they cannot be accounted true mineral species, 

and properly ought not to be included in a treatise on 

mineralogy. Some of them, however, from their importance 

in the arts, others from other circumstances, have re- 

ceived distinct names and a kind of prescriptive right to a 

place in mineralogical works, from which they can now 

scarcely be banished. Many of them are properly rocks, 

or indefinite combinations of two or more minerals $ others 

are the mere products of the decomposition of such bodies. 

Their number is of course indefinite, and their introduction

CLASSIFICATION OF MINERALS. 131 

tends much to render mineralogy more complex and diffi- 

cult, and to destroy its scientific character. 

In collecting the species into higher groups, and arrang- 

ing them in a system, several methods have been pursued. 

Some, like Mobs, have looke.d only at the external charac- 

ters, and asserted that they alone were sufficient for all the 

purposes of arranging and classifying minerals. Others, 

led by Berzelius, foave, on the contrary, taken chemistry as 

the foundation of mineralogy, and classed the species by 

their composition, without reference to form or physical 

characters. 

Neither system can be exclusively adopted, and a nat- 

ural classification of minerals should take into account all 

their characters, and that in proportion to their relative 

importance. Among these the chemical, composition undoubtedly 

holds a high rank, as being that on which the 

other properties will probably be ultimately found to de- 

pend. Next in order is their crystalline form, especially 

as exhibited in cleavage ; and then their other characters 

of gravity, hardness, and tenacity. But the properties of 

minerals are as yet far from showing that subordination 

and co-relation which has been observed in the organic 

world, where the external forms and structures have a direct 

reference to the functions of the living being. Hence, even 

when all the characters are taken into account, there is not 

that facility in classifying the mineral that is presented by 

the other kingdoms of nature. Many, or rather most, of 

the species stand so isolated that it is scarcely possible tp 

find any general' principle on which to collect them into 

large groups, especially such groups as, like the natural 

families of plants and animals, present important features 

of general resemblance, and admit of being described by 

common characteristics. Certain groups of species are 

indeed united by such evident characters, that they are

132 A POPULAR TREATISE ON GEMS. * 

found together in almost every method ; but other species 

are not thus united, and the general order of arrangement 

is very uncertain. Hence, though some classifications of 

very considerable merit have been proposed, no natural 

system of minerals commanding general assent has yet 

appeared. 

The 

. 

arrangement followed in this treatise is chiefly 

founded on that proposed by Professor Weuss of Berlin. 

We have, however, made considerable changes, which the 

progress of the science and the more accurate knowledge 

of many species require. This classification appears to us 

to come nearer than, any other we have seen to a natural 

system, which in arranging and combining objects takes 

account of all their characters, and assigns them their place, 

from a due consideration of their whole nature, and is thus 

distinguished from artificial systems, which classify objects 

with reference only to one character. 

Besides species, two higher grades in classification seem 

sufficient at once to exhibit the natural relations, and to 

facilitate .an easy and complete review of the species com- 

posing the mineral kingdom. These are families and orders. 

In forming the families, those minerals are first selected 

which occupy the more important place in the composition 

of rocks, and consequently in the crust of the globe. Thus 

quartz, felspar, mica, hornblende, garnet, among siliceous 

minerals; calc-spar, gypsum, rock-salt, less so fluor spar 

and heavy spar, among% those of saline composition, stand 

out prominently as the natural centres or representatives of 

so many distinct families. To these certain metallic miner- 

als, as iron pyrites, lead-glance or galena, blende, magnetic 

iron ore, the sparry iron ore, and a few more, are readily 

associated as important families. But the minerals thus 

geologically distinguished are not sufficient to divide the 

whole mineral kingdom into convenient sections, and addi-

CLASSIFICATION OP MINERALS. 133 

tional groups must be selected from the peculiarity of their 

natural-historical or chemical properties. Thus the zeolites 

are easily seen to form such a natural group. The 

precious stones or gems also, notwithstanding their diverse 

chemical composition, must ever appear a highly natural 

family, when regarded as individual objects. Their great 

hardness, tenacity, high specific gravity without the me- 

.tallic aspect, their brilliant lustre, transparent purity, and 

vivid colors, all mark them out as a peculiar group. Only 

the diamond, which might naturally seem to take the chief 

place in this class, differs so much, not only in elementary 

composition, but in physical properties, that it must be 

assigned to a different place. 

Round these .species thus selected, the other Jess import- 

ant minerals are arranged in groups or families. It is evi- 

dent? that no precise definition of these families can be 

given, as the connection is one of resemblance in many 

points, not of identity in any single character. In other 

words, it is a classification rather according to types than 

from definitions, as every true natural classification must 

be. The same cause, however, leaves the extent of the 

families somewhat undefined, and also permits considerable 

license in the arrangement of species. But both circum- 

stances are rather of advantage in the present state of the 

science, as allowing more freedom in the grouping of spe- 

cies than, could be obtained in a more rigid system of clas- 

sification. 

In collecting the families into orders, the guidance ot 

chemistry is followed rather than of natural history, thougli 

the latter is also takenjnto consideration. Chemical names 

are assigned to the orders, but still regarded as names de- 

rived from the prevailing chemical characters, and not as 

definitions. Hence it must not be consider^! an error 

should two or three mineral species be found in an order


with whose name, viewed as a definition, they may not 

agree. 

Guided by these and similar considerations, minerals 

may be divided into the following 

ORDER I. THE OXIDIZED STONES. 

orders and families : 

Families. -1. Quartz. 8. Serpentine. 

2. Felspar. 9. Hornblende. 

3. Scapolite. 10. Clays. 

4. Haloid stones. 11. 'Garnet. 

5. Leucite. 12. Cyanite. 

6. Zeolite. 13. Gems. 

7. Mica. 14. Metallic stones.' 

ORDER II. SALINE STONES. 

families. 1. Calc spar. 4. Gypsum. 

2. Fluor spar. 

* 

5. Kock salt. 

3. Heavy spar. 

ORDER III. SALINE ORES. 

Families. -1. Sparry iron ores. 8. Copper salts. 

2. Iron salts. 4. Lead salts. 

ORDER IV. OXIDIZED ORES. 

Families. I. Iron ores. 4. Red copper ores. 

2. Tinstone. 5: White antimony ores. 

3. Manganese ores. 

Families. I. Iron pyrites. 

ORDER V. NATIVE METALS. 

Form only one family. 

ORDER VI. SULPHURETTED METALS. 

4. Gray copper ore. 

2. Galena. 5. Blende. 

3. Gray antimony ore. 6. Ruby-blende. 

ORDER VII. THE INFLAMMABLES. 

Families. I. Sulphur. 

4. Mineral resins. 

Diamond. 5. Combustible salts. 

Coal.

PART II. 

THE GEMS. 

+ * 

PRECIOUS STONES OK GEMS. 

PRECIOUS stones or gems are such minerals as, either from 

their beauty or other valuable properties, have become the 

subject of the arts or trade, and are used as ornaments, or 

employed by jewellers. In order to appreciate more fully 

such minerals as may possess superior virtue, it is our pres- 

ent object to consider them in reference to their scientific 

and practical value. 

DIVISION OF GEMS. 

Gems are generally classed as follows: 1st, real gems, or 

jewels ; and 2d, semi-gems, or also precious stones. The first 

comprise such minerals as combine, within a small space, 

either vivid or soft and agreeable colors, with a high de- 

gree of lustre, usually termed fire, as well as hardnes's; 

the second possess these characters inâ less degree, and 

occur often semi-transparent or translucent, and in larger 

formless masses. It is, however, impossible to draw a 

Gtrict line between them, as the conventional value put upon 

the one or the other also affects their character ; for very 

often some, which are generally considered as belonging 

to the second class, may be valued, for their peculiar prop- 

erties, much higher than some of the first class.


Those species of minerals which are generally considered 

real gems are 

Diamond, Garnet, 

Sapphire, 

Chiysoberyl, 

Spinelle, 

Tourmaline, 

Rubellite, 

Essonite, 

Emerald, Cor.dierite, 

Beryl, . lolite, 

Topaz, 

Quartz, 

Zircon, Chrysolite. 

The rest are considered as semi-precious stones. 

COLOR, GRAVITY, AND HARDNESS OF GEMS. 

The precious stones possess the colors in their highest 

perfection, and their principal and intrinsic value depends 

and as most gems occur in va- 

mostly upon this property ; 

rious colors, the following table will exhibit them, along 

with their specific gravity and hardness : 

LIMPID "GEMS. 

SPECIFIC GRAVITY. HAKDNESS. 

Zircon 4-41 to 470 7'5 

Sapphire 3-9 4-20 7- 

Diamond 3-5 3'6 10' 

Topaz (Pebble) 3-49 3-56 8- 

Eock Crystal (False Diamonds, Lake George, 

Trenton Falls) 2'69 7* 

Beryl, Aquamarine , 2-67 2'68 7'5 

BED GEMS. 

Zircon, Hyacinth 4-41 4-70 7'5 

Garnet (Oriental Garnet) 4'0 4-2 6'5 

Sapphire, Ruby .. 4>0 4'2 9' 

Garnet, Bohemian Garnet. Pyrop 3'7 3'8 6'5 

Spinelle, Ruby Spinelle, Ruby Balais 3'49 3*7 8- 

Diamond 3-5 3*6 10- 

Essonite 3'5 3-6 7' 

Topaz. "Brazilian Topaz (often burnt) 3'52 8'56 8-

GRAVITY AXD HARDNESS OF GEMS. 137 

SPECIFIC GRAVITY. HABDUKSS. 

Tourmaline, Siberite, Eubellite 3*0 to 3-30 6*5 

Rose Quartz. Bohemian Ruby 2'50 2*63 7' 

Carnelian 2'5 2'6 ? 

YELLOW GEMS. 

Zircon 4-41 4'50 7 '5 . 

Sapphire. Oriental Topaz ; '. . 4-0 8- 

Chrysoberyl 3'65 3'80 8'5 

Topaz. Brazilian, Saxonian, and Syrian Topaz 3'50 3'56 8' 

Diamond '. 

. . . 3-5 3-6 10* 

Beryl ; 2'67 2'7l 1'S 

Rock Crystal, Citron 2'60 2'69 7- 

Fire-opal 1-90 2-12 5-5 

GREEN GEMS. 

Zircon 4-41 

Sapphire, Oriental 

Chrysolite, and Emerald .. 3'9 

4'50 

4'00 V 

Malachite 3>6T 3-5 

Chrysoberyl 3'59 3'75 8'5 

Spinelle , 3-58 3'64 8' 

Diamond 3-5 3'6 10' 

Topaz. Aquamarine 3-49 3-56 s* 

Chrysolite 3'33 3'44 6'5 

Idocrase 3'08 3'40 6'5 

Tourmaline (Brazilian and Maine) 3'00 3-30 6-5 

Emerald.. 

* 

2'67 2'73 7'5 

Berj'l 2-67 271 7'5 

Prase... 2-66 2'6S f- 

HeHotrope 2'61 2-63 7" 

Chrysoprase 2'5S 2-60 7- 

Felspar, Amazon Stone 2'50 2'60 6' 

BLUE OEMS. 

Sapphire 3'90 4'00 8' 

Disthene (Kyanite) '. . , 3'50 S'67 5' 

Spinelle 3'58 3'64 8' 

Diamond 3'5 3'6 10- 

Topaz. Brazilian Topaz 3-49 3'5ft S- 

Tourmaline, Indigolite : 3'00 3'30 6'5* 

Turquoise 2*86 3*00 6- 

Beryl, Aquamarine .* 2-67 2*71 7'5 

Dichroite (loUte) 2-58 2-60 7*


' 

SPECIFIC GRAVITY. HARDNESS, 

Hauyne 2-47 5' 

Lazulite 2-30 5- 

* VIOLET GEMS. 

Garnet 4'0 to 4-2 6'5 

. Sapphire, Oriental Amethyst 3 ! 

9 4'0 9- 

Spinelle '. 3'58 3'64 8* 

Axinite 3'27 6'5 

Tourmaline 3'00 3'30 6'5 

Amethyst : 2-65 2'7S 7' 

BROWN GEMS. 

Zircon 4'41 4'50 7'5 

Garnet 

' 

4-00 4'20 6'5 

Essonite 3-53 3'60 7' 

Diamond 3'50 3-60 10' 

Toifrmaline 3'00 3-30 6*5 

Smoky Quartz .2-69 2*70 7' 

BLACK GEMS. 

Diamond 3-50 3'60 10* 

Tourmaline 3'00 3'30 6' 

Eock Crystal, Morion 2'69 2'7l 7' 

Obsidian 2-34 2'39 6"-o 

Pitch Coal . 1-29 1-35 2- 

CannelCoal : 1*23 1'27 2' 

GEMS DISTINGUISHED FOK THEIR VARIOUS SHADINGS OF COLOR 

AND LIGHT. 

Garnet 4-00 4'20 6-5 

Sapphire, Star Sapphire 3'90 4'00 9 - 

Chrysoberyl 3*70 3'SO 8'5 

Hypersthene 3'38 6- 

Labrador Spar 2-71 2'75 6- 

Dichroite 2'58 2'60 7' 

Cat's-eye .* 2'56 2'73 7' 

Adularia 2-50 2'60 6' 

Felspar 2'50 2'60 6- 

Precious Opal 2-00 2-10 5'5 

Hydrophane 1'90 2'00 5- 

A number of precious stones do not possess a local color, 

'

COMPOSITION OF GEMS. 139 

but merely a tinge or a shade of color ; and these we dis- 

tinguish by the following degrees of dark, high, light, and 

pale colored, or tinged. Another distinction may be detected 

in precious stones as possessing either one or more 

colors, or a variegated color ; or as being spotted, painted, 

stained with the different colors. These latter characters 

are, however, more proper to the semi or common precious 

stones, than to gems. 

CHEMICAL CHARACTERS. 

Although mineralogy could nqt exist, as a science, without 

the aid of chemistry, and whole systems or classifica- 

tions have been established, as well as the constituent parts 

of minerals determined, by the knowledge of Chemical char- 

acters, still it is difficult to resort to chemical means for distinguishing 

the gems or precious stones, as they would be 

destroyed by such an examination, and we can, for that 

purpose, only employ splinters or fragments. The most 

simple mode of proceeding is to test 

1st, Their greater or less fusibility, with or without a flux ; 

2d, Their behavior before the blowpipe, an instrument 

highly convenient, and, indeed, indispensable to the miner- 

alogist ; and, 

3d, The action of the acids upon them. 

All of these means, however, have not an effect upon all 

gems, as many of them, for instance, are either infusible, or 

fusible with the greatest difficulty by the addition of a flux. 

COMPOSITION OF GEMS. 

The attention "of writers, as far back as 1502, had been 

directed to the establishment of some hypothesis as to the 

composition .and origin of the gems, and many fabulous* 

views were entertained in respect to their formation. 

There was also connected with some hypotheses a species


of medical superstition as to their effect. Boyle (1672) 

formed from clear 

thought that all gems were originally 

limpid water, and that they received their color and other 

properties from their metallic spirit. Others considered a 

peculiar earth, called the noble or precious earth, as the 

principal ingredient of the precious stones. Bruckman 

(1778) recognized quartz as the principal of the gems. 

Bergman thought that gems were all composed of the same 

ingredients, such as alumina, silex, and lime, and that the 

different proportions produced the different species ; and 

the older mineralogists determined the character of the 

gems by their hardness, lustre, structure, and resistance to 

acids. But modern chemistry has ascertained the compo- 

nent parts, and other characters of gems, with more cer- 

tainty, and it is satisfactorily proved that the principles 

they contain are the earths, such as silica, alumina, and 

lime ; that some contain a peculiar earth (such is the case 

with the zircon, emerald, and chrysoberyl), and that the 

diamond, at the head of gems, consists of pure carbon,

ARTIFICIAL PRODUCTION OF GEMS/ 141 

Mr. Gaudin has, by means of the compound blowpipe, 

been able to fuse alumina and quartz, and from potassa 

and ammoniacal alum he has produced well-formed corundum 

crystals, as also crystals of ruby, of rhombohe- 

dral form and triple cleavage, and which, according to 

Malagutti, consisted of ninety-seven alumine and two silicate 

of lime, the exact composition of ruby. By this process 

the potassa originally employed was volatilized in the high 

temperature; this was done in 1837. Becquerel employed 

electricity for this purpose in its most attenuated condition, 

and with two or three bodies, one of which in its dry and 

the other in liquid state, and required from one to two 

years to effect its object, as the case was with a dodecahedral 

pentagonal crystal of iron pyrites he obtained ; 

sulphu- 

rets of copper and tin, which could not be distinguished 

from the native crystals. He has even obtained crystals of 

oxide of zinc, which- were octahedral, transparent, refract- 

ing strongly the light, and hard enough to scratch glass, 

and altogether unknown in the mineral kingdom. His 

process was, on a silicate of potassa solution to let act- 

slowly a voltaic current from a sheet of zinc, around which 

a copper wire was wound. The density of the liquid was 

22 areometer; water was thereby decomposed with dis- 

engagement of hydrogen gas 

and formation of oxide of 

zinc, which was dissolved again, and after a fortnight, very 

fine brilliant crystals were visible on the zinc plate, which, 

after a lapse of two years, were the size of a millimeter. 

Mr. Ebelman conceived the idea of obtaining artificial^ 

crystals from infusible silicates and aluminates, by replac- 

ing the water contained in many metallic oxides in higli 

temperatures with boracic acid, borate of soda, phosphorus, 

and alkaline phosphates, and its final evaporation in high 

temperatures. He prepared certain oxides, calculating 

the proportions, such as alumina and silica, and exposed

142 'A POPULAR TREATISE ON GEMS. 

them in a platina capsule, at a high temperature, in his 

porcelain furnace of the Sevres manufactory, of which he 

was the director, and with the mixture of boracic acid kept 

the mass in a fusion, and the corundum and crystallized 

silex were the results. He used boracic acid for this purpose, 

as he found it more convenient than the other, dissolvents. 

Mr. Ebelman has fused together, in order to obtain the 

spinelle (which is composed of. 72 parts of alumina and 28 

parts magnesia), 

Alumina, 

Magnesia, 

Fused boracic acid, 

- - G grammes. 

- -. 3 

Green oxide of chrome, O'1-O to 0*15 grammes. 

The latter was added for the purpose of rendering the mass 

of a rose color. This mixture, put into an uncovered pla- 

tina capsule, was exposed to the heat of the porcelain fur 

nace ; after the baking was finished, the melted mass formed 

a rose-colored layer on the bottom of the capsule, and in 

the mass octahedral crystals of spinelle, quite identical with 

the natural crystals of the ruby spinelle, were taken out, 

which were exceedingly Brilliant. The author received in 

1851, while on a visit to Paris, from Mr. Ebelman, about 

thirty of those crystals, weighing about one grain, and 

which he submitted, on his return to the United States, to 

numerous chemical and mineralogical tests, both as to 

hardness, specific gravity, and lustre, and was extremely 

gratified as to its results. 

Mr. Ebelman manufactured the blue spinelle, by substi- 

tuting the same quantity of oxide of cobalt for the oxide of 

chrome; also by substituting the oxide of zinc for .the 

magnesia, he obtained the garnet, which he prepared by 

- 6 

Alumina, 

Oxide of zinc, 

Fused boracic acid, 6 

" 

" . 

- 6 grammes. 

- 5 * " 

"

ARTIFICIAL PRODUCTION OF GEMS. 143 

The mass was brought slowly to a white-heat temperature, 

and kept from twenty-four to thirty hours in that condition. 

The boracic acid begins to evaporate during the last five 

hours. 

The emerald was obtained artificially by a mixture of 

Silex, 

Alumina, 

- -4 grammes. 

- T60 " 

Glucia, - - 1-40 

Fused boracic acid; 4*06 

Oxide chrome, 

" 

" 

- O'lO " 

Mr. Daubree has produced artificially the oxide of tin, 

by passing through a heated porcelain tube two currents 

of the vapors of the perchloride of tin and water, by which 

a double decomposition was effected, so that in the interior 

of the porcelain tube small crystals of oxide of tin were de- 

posited, arid hydrochloric acid gas passed off in the form of 

vapor. The crystals of tin- were deposited at the orifice of 

the porcelain tube, where the temperature was scarcely 

300, while no crystals were deposited in the hottest part ; 

the crystals of tin scratched glass easily, were infusible, 

and were, not affected by acids, and had a specific gravity 

of 6-72. 

The latest discoveries of Mr. Daubree have .brought to 

light many important facts in regard to the formation of 

rocks which contain crystalline substances, differing widely 

in their fusibility. By the action of chloride of silicium at 

red heat, and vapor on many bases which enter into various 

rocks he obtains in exchange, by decomposition, chlorine 

bases and free silica (silicic acid), which appears as quartz 

in crystals ; if he desires an action of the chloride of sili- 

cium on chalk, magnesia, alumina, or glucia, he obtains 

crystals of quartz, wallastonite, peridote, and -disthene ; 

the purpose of obtaining double silicates, he not only adds 

the bases for silicifying in proper proportions, but also in 

for

144 A POPULAll TKEATISE ON GEMS. 

excess sufficient oxygen for forming silicic acid. A mixture 

of chalk or magnesia, for instance, to the chloride of sili- 

cium, produced crystals of diopside, perfectly colorless, 

with a characteristic slope of this mineral. He also ob- 

tained crystallized felspar by the mixture of 1 equivalent 

of alkali (potassa and soda), 1 equivalent of alumina, with 

6 equivalents of lime under the influence of chloride of si- 

licium. Similar mixtures have produced crystals of garnet, 

idocrase, phenakite, emerald, euclase, zircon, and wilhelm-" 

ite. He also produced tourmaline in regular hexagonal 

prisms, which were grouped upon quartz crystals just as 

they are often observed in crystalline rocks of shorl. By 

the same method, but replacing the chloride of aluminum 

for action upon the bases, he obtained corundum crystals, 

the contact of 

spinelle crystals, and garnet crystals ; by 

perchloride 

of iron with chloride of zinc he obtained fine 

crystals of franklinite ; crystals of magnesia or periclase, 

like those from Mount Somma, were produced by the 

action of lime on chloride of magnesium, but remarkable 

enough, their production is just the counterpart of the ori- 

gin of the native mineral, where constantly chlorine vapors 

are disengaged, and where it detaches itself from the dolo- 

mite geodes. 

Mr. Durocher obtained, by the action of sulphuretted 

hydrogen gas upon the chlorides of iron and zinc, crystals 

of magnetic pyrites and blende ; he also obtained, by the 

action of different vapors, sulphurets of antimony and 

arsenic, and the gray antimonial copper. 

Mr. Senarmont obtains quartz crystals in perfect hexagonal 

prisms, with all the other specific characters, from the 

gelatinized silica, under a high temperature and the high 

pressure of thirty atmospheres. 

The artificial production of the diamond has been latterlyeffected 

by the ingenious contrivance of Despretz, which

GEOLOGICAL CHARACTERS. 145 

consists in passing an electric current "into an exhausted 

bottle, in the lower part of which is placed a small cylinder 

of charcoal, and from the upper part "are suspended pla 

tina wires or platiua foils; the sparks thereby obtained 

from the combustion of the charcoal are of a reddish-violet 

color ; 

after the lapse-of one month, during which the com- 

bustion continues, a little black layer of charcoal is depos 

ited upon the platina ; 

under the microscope they appear 

like very small octahedrons, quife analogous to the diamond 

some were free from ; 

color, and very brilliant. 

GEOLOGICAL CHARACTERS. 

The origin, locality, and geological characters of gems 

it was formerly supposed that the trap forma- 

are various ; 

tion was their matrix ; but it is ascertained that we find 

them distributed in rocks of different ages and kinds, either 

as accidental mixtures such as garnet in gneiss and mica- 

ceous schiste or in drusy cavities, such as the emerald, 

which occurs in druses of argillaceous slate and micaceous 

schiste ; and many precious stones are found- in gangues. 

Many gems are found at a distance from their original bed, 

on secondary or diluvial strata, or &i the beds of rivers, 

mixed with their sand. Thus, zircon is found in Ceylon in 

regular beds ; and likewise we find in Ceylon, after much 

rain, the topaz, zircon, and other gems. This happens 

more frequently in the beds of the rivers, and then the 

gems appear often in the shape of pebbles, showing that 

those hard stones, carried away from their original beds, 

have been rolled and rounded by the streams and rivers, 

although they retain sometimes their crystalline structure, 

on account of their hardness. 

The discovery of diamonds in Russia, far from the tropi- 

cal region, has excited "much interest among geologists. 

7


In the detritus on the banks of the Adolfskoi, no fewer 

than forty diamonds have been found in the gold alluvium, 

only twenty feet above the stratum in which the remains 

of mammoths and rhinoceroses are found. Hence Hum- 

boldt has concluded that the formation of gold-veins, and 

consequently of diamonds, is comparatively of recent date, 

and scarcely anterior to the destruction of the mammoths. 

Sir Roderick Murchison and M. Yerneuil have been led to 

the same result by different arguments. 

GEOGRAPHICAL DISTRIBUTION. 

The locality of gems bears some highly interesting 

characters, inasmuch as we may sometimes judge, from 

. their appearance, the climate of their locality ; and it 

seems as if the countries ofthe torrid zone had been par- 

ticularly favored by nature in producing the most precious 

gems, or that those hot-beds were more propitious to the 

formation of the blossoms of the inorganic world. Com- 

paring, for instance, spinelles and zircons, from Siberia, 

with those of Ceylon and Peru, we find the first to be dark 

and of an impure color, as if emblematic of a cold, un- 

friendly, northern climate ; 

whereas the latter glitter with 

full brilliancy, and possess all those properties and beauties 

for which gems are so highly esteemed. Often, too, we 

find the gems collected in particular countries, or isolated 

spots of our globe, such as the most precious gems from 

the East Indies and Brazil, where, singular enough, they 

occur with the precious metals ; as, for instance, the diamond 

in company with gold and platina in Brazil. Some 

of the gems have likewise been hitherto discovered in a 

single spot on one continent only, and are then exhausted*; 

' 

such as the rubellite, in Maine, United States the iolite in 

; 

Connecticut, United States, and the lazulite in Persia.

NOMENCLATIVE OF GEMS. 147 

PRACTICAL DIVISION AND NOMENCLATURE OF GEMS. - 

Artists have not profited, in their arrangement and no- 

menclature of gems, by the advanced state of mineralogy, 

and although they have been newly classified 

as a science ; 

by mineralogists according to their scientific characters, 

the practical artist arranges them according to those properties 

that principally attract the eye : such as color, trans- 

parency, and lustre. Gems have, in consequence, received 

their names from their color : as ruby, from its red color ; 

sardonyx, yellow onyx. Gems of different species, but of 

the same color, are often named from their color. For 

instance, the corundum, the spinelle, or the topaz, if of a red 

color, is called ruby ; if blue, sapphire ; if green, emerald ; 

if yellow, topaz, and if violet, amethyst : and thus gems of 

the same color, but of different composition, are arranged 

under the same head. The artist confounds under the 

name of Brazilian ruby, either a light rose-red spinelle, 

or a topaz approaching to the red color. The name of a 

country or locality, is often sufficient to give a name to gems 

of the same color, but of different shadings, and of more 

or less vivid lustre. Thus, by Oriental chrysolite is meant 

a yellowish-green sapphire, and by Saxonian chrysolite, a 

pale wine-yellow topaz. Many gems have always been 

known under the name of Oriental gems, partly because 

they were first obtained in the East, and partly because 

they stood, from their excellent properties, in higher estimation 

than those from an^ other country. Those from 

the East were likewise callecf " Oriental," in opposition tQ 

others less valuable, which were called " occidental" gems. 

Subsequently, all gems of superior qualities were called 

Oriental gems, even when their locality was not in the 

East. Thus, for instance, that precious opal, so well distinguished 

for its beautiful play of colors, is called the On-

148 A PQPUIAR TREATISE ON GEMS. 

ental opal, although it is never found there ; likewise, the 

purest and most valuable emerald, which in great perfection 

only occurs in Peru, is known as the Oriental emerald. 

HISTORY OF GEMS. 

Those precious stones, which are now called gems, were 

known in ancient times but very little, if at all. The first 

notice given of them is in the Bible, where it is stated that 

the high priest wore one stone on his gold scarf, and twelve 

gems set in gold plate, called the Urim and Thummim, 

each of which represented a tribe. It appears that the 

Hebrews borrowed the names of their gems from the 

Egyptians, and few of the gems with the exception of 

the sapphire named in the holy Scriptures correspond in 

any respect with those at present known in our mineralogical 

books. The Greeks appear to have been but little ac- 

quainted with gems, as they did not use them as ornaments 

in the Trojan wars; and Homer, when speaking of the 

treasures of those tunes, does not make any mention of 

gems. Theophrastus and Pliny have described some gems 

of their time very imperfectly and confusedly ; and their 

descriptions are so replete with vain fancies, that it is diffi- 

cult to identify any from their descriptions. They attributed 

most wonderful powers to gems ; gave fabulous descriptions, 

and the most singular and perverted views in regard to 

their origin ; 

and it was said that they had great influence 

upon health and beauty, riches, honor, and good fortune. 

They were called, when worn,*amulets. They were brought 

into connection with the planets, the twelve constellations, 

and the seasons of the year ; and a certain gem was worn 

each month, which was said to have during the term, its pe- 

culiar influence and healing virtues. Such superstitious 

notions have been transmitted to our times. The gems cor-

HISTORY O? GEMS. 14p 

responding to the different months, and also to the twelve 

Jewish tribes, are the following : 

January Hyacinth "Dan. 

February Amethyst Gad. 

March Jasper Benjamin. 

April Sapphire Issaehar. 

May Agate Naphtali. 

June Emerald Levi. 

July Onyx Zebulon. 

August Carnelian .. Reuben. 

September Chrysolite Asher. 

October Beryl Joseph. 

November Topaz ". Simeon. 

December Ruby Judah. 

Artists have made certain changes in some of the gems 

corresponding to the months, and the tribes represented 

in the Urim and Thummim ; they consider May to be repre- 

sented by emerald : 

June by Chalcedony, Onyx, or Agate ; 

July 

CarneliarT ; 

August Sardonyx ; 

October Aquamarine ; 

December Chrysoprase, Turquoise, or Malachite. 

In the early ages similar views were entertained in the 

East, and many of them are yet prevalent. The Persians 

believe that spinelle affords joy, and 'protects them against 

bad dreams. The Indians believe in the efficacy of large 

diamonds to bring them back to their families. (The Rajah 

of Mattan, a district of Western Borneo, possessed a. diamond 

of 367 carats.) The ruby is esteemed, in the East, 

as a talisman, Avhich is never shown willingly to friends ; 

it is considered ominous if it contains any black spots. The 

Chinese, on the contrary, present the same stone as a testimony 

of friendship. The Peruvians adore the emerald as


their deity. Many of these fabulous notions were probably 

brought from the East to Europe; for we find, in the 

middle ages, similar views entertained by Marbodus, Bishop 

of Rennes, who wrote a book on the miraculous powers of 

gems. The twelve Apostles were likewise represented 

symbolically by gems, and they were called " the Apostle 

gems;" as 

Jasper for St. Peter ; 

* 

St. Andrew ; 

Sapphire 

Chalcedony 

St. James ; 

Emerald St. John ; 

Sardonyx 

St. Philip; 

Carnelian St. Bartholomew ; 

Chrysolite ; St. Matthew ; 

Beryl St. Thomas ; ^ 

Chrysoprase.. St. Thaddeus ; 

Topaz 

St. James the Less ; 

Hyacinth 

St. Simeon ; 

Amethyst St. Matthias. 

The ancients, induced by the beauty of gems the pure 

and deep color of the emerald, the vivid and high lustre 

of the diamond, and the agreeable reflections of the opal 

had commenced using them as ornaments and jewelry, 

and they took pains to adapt them to their purposes. 

Although they did not, in 'those times, understand the art 

of cutting and polishing them as practised at the present 

time, yet they endeavored to work them into all possible 

shapes, by rubbing off the corners, or polishing the natural 

faces. They generally fixed the gems on strings ; they 

also tried to carve figures representing deities, religious 

costumes, historical events, exploits of celebrated generals, 

or the heads of great men.

SCULPTURE IN GEMS. 151 

SCULPTURE IN GEMS. 

The art of carving was well known to the ancients, and 

those stones were called gems, in the proper sense of the 

word, which had figures or letters engraved on them in a 

very small compass, the workmanship of which we, at this 

day, cannot help admiring. 

is the 

Gem-sculpture, or the glyptic art (or lithoglyptics), 

art of representing designs upon precious stones, either in 

raised work (cameos) or by figures cut into or below the 

surface (intaglios). The first were most natural to the 

rising art, and were used as seals ; 

whereas the latter were 

used as ornaments, for which the most precious materials 

were employed, according to the state .of the art. They 

did not understand engraving on diamonds, or many 

other gems : they employed only the softer stones, the 

common precious stones, such as earn eh* an, onyx, jasper, 

&c. ; they also used paste, or artificial colored glass composition, 

for their engravings. Their mode of working was 

very simple :' the polishers prepared then* stones on a plate, 

by means of the powder of harder stones, either round, 

oval, flat, or in shield form, according to the designed sub- 

ject, and then left to the sculptors the subject of the engraving, 

which was done by means of iron, or diamond 

splinters mounted in iron. It was not until the year 1500 

that Ambrosius Caradossa first discovered the method of 

cutting the diamond. He prepared the figure of a patriarch 

for Pope Julian n. He also discovered the first traces of 

sculpture among the Jews, Persians, and Egyptians. In 

the traditions of the holy Scriptures, Moses, for instance, 

had the names of the twelve tribes of Israel engraved on 

the gems used by the high-priest. Solomon possessed a 

seal : Alexander presented his seal to Perdicas. Augustus 

had a sphinx engraved on his seal ; but the Indians and

152 A POPULAK TREATISE ON GEMS. 

Persians engraved mostly mythological animals or priests 

in their gems the ; Egyptians, beetles, which they adored, 

and which are called the 

" 

scarabsei. Abraxes" were the 

oldest gems, which had the representation of fantastical 

animals, with the above word in 

graved on them. 

the Greek language, en- 

The Phenicians, Hetrurians, and Greeks learned the 

and from them it was 

art of carving from the Egyptians ; 

carried to the Romans, where it was lost, in the decline 

of the empire, in the fifteenth century, under the Popes 

Martin V. and Paul II. The art was revived again by 

some fugitive Greeks in Italy. Great merit is also due to 

the Medicians for the revival of the art ; and Giovani was 

considered the first in Italy. The talisman, or carved 

gems bearing Arabian letters, belong to those times. 

Precious stones with layers and veins, or such as onyx, sar- 

donyx, &c., were employed by the ancients, with great 

skill, in the carving of cameos, where we find the head of 

one color, and the hair and dress of a different color carved 

out of the other layer of the stone. Very often the sub- 

jects were mythological, and this mode of carving or sculpture 

has been imitated by modern artists. It is sometimes 

with difficulty that Ave are enabled to distinguish the an- 

cient from the modern works, and the only authentic 

authority for the antiquity of the cameo or intaglio is its 

excavation from ancient monuments, except in a few in- 

stances, where we may be able to judge by comparison of 

the difference in antiquity ; by observing whether or not 

they, are unnaturally, or stiffly done;. have large heads, 

hands, and feet, or stiff streaks resembling the hair, &c. 

We find that some gods, representing the peculiar gems 

(such we see all sculptures of Bacchus, and what relates to 

him), were executed in amethyst, being the color of wine ; 

and all nymphs, Neptune, or fish, in aquamarine,

ON GRINDING. 153 

color of water. We find also, in Germany, traces of sculpture 

in the fourteenth and sixteenth centuries ; the oldest 

known artist, Daniel Engelhard, at Kuremburgh, died in 

1552 ; also Lucas Kilian; and the best artist, Nater, died 

in 1705. England and France had likewise very distinguished 

artists in carving. A full history of gem-sculpture 

may be found in the Encyclopedia Americana, pp. 403-405. 

ON GRINDING. 

The art of grinding gems is of more modem origin; it 

consists in cutting the gems, and other precious stones, into 

figures, bounded by many planes, and by polishing the 

faces thus formed, increasing their lustre, transparency, and 

other valuable properties. This constitutes the work of 

the lapidary. In the year 1290 a society of lapidaries was 

formed at Paris, and in 1385 there were diamond-cutters at 

Nuremburgh ; 

but it Avas not until 1456 that Ludwig Yan 

the diamond with its 

Bergen invented the art of polishing 

own powder; gems were then cut according to mathematical 

principles; the art has been brought, in modern 

tunes, to the greatest perfection. There is a great difference 

in gems (which are mostly procured from the Indies in a 

rough or polished state), easily to be detected by their im- 

Fig. 1. Fig. 1 a.

154 A POPULAR TREATISE OX GEMS. 

perfections. The Indians look more upon the size of the stone 

than upon the cut, which is generally irregular and devoid 

of symmetry. We observe this in the two celebrated diamonds 

of the Shah of Persia, the Dariainur brilliant sea 

(figs. 1 and 1 a), and the Kuinur brilliant mountain 

(figs. 2 and 2 a)", the one is worn on the left arm, and the 

other on the right knee. 

/ 

Fig. 2. 

Fig. 2 a. 

By looking at the subjoined representation 

of the dia- 

mond belonging to the crown of France (figs. 3 and 3 ), 

which weighs one hundred and thirty-six and a quarter 

carats, is fourteen lines long, thirteen and a quarter lines, 

broad, and nine and a quarter lines thick, and which is 

known by the name of liegent, we can more distinctly dis- 

criminate the irregular and unmathematical cut. 

The gem-grinders are divided into three classes: first,

OX GELSTDING. 155 

Fig. a . 

^ 

Fig. So. 

the diamond ; second, the gem ; and third, the jewelry 

grinders. 

The diamond grinder divides his work into


furrow is obtained, which will render the planes suitable 

for applying the cleaving instrument, and this operation is 

repeated with every plane. 

Diamonds that are not fit for 

being cloven, are called by the Dutch, " divelsteene" (devilstones). 

Large diamonds, which are too precious to be 

expose to a dangerous cleavage, are sawed by means of a 

fine steel wire, moistened with oil and diamond-powder. 

The rough-cut diamonds, as they are brought from the 

Indies, are called laborer. 

Mr. Mawe gives the following description of the art of 

diamonds : 

cutting -and polishing 

" The object of cutting and polishing the diamond is 

twofold : 

" First, to divide the natural surface of the stone in a 

symmetrical manner, by means of a number of highlypolished 

polygonal planes, and thus to bring out to the 

best advantage the wonderful refulgence of this beautiful 

gem ; and, secondly, by cutting out such flaws as may 

happen to be near the surface, to remove those blemishes 

that materially detract from its beauty, and consequently 

from its value. 

" The removal of flaws is a matter of great importance: 

for, owing to the form in which the diamond is cut, and its 

high degree of refrangibility, the smallest fault is magnified, 

and becomes obtrusively visible in every facet. For this 

reason, also, it is by no means an easy matter, at all times, 

to ascertain whether a flaw is" or is not superficial ; and a 

person with a correct and well-practised eye may often purchase, 

to great advantage, stones which appear to be flawed 

quite through, but are, in fact, only superficially blemished. 

"The first thing the artist has to do, when a rough diamond 

is put into his hands, is to examine carefully in what 

direction the stone may be cut, so as to afford the greatest 

breadth, or spread, as it is technically termed, after the 

'

ON GRINDING. 157 

a stress 

flaws, if any, shall have been taken out. f So great 

is laid, by modern fashion, on the superficial extent of a 

brilliant, that the old rules of proportioning its dimensions 

are now nearly obsolete: the best cutters have entirely 

discarded the use of measures, and, in forming the facets, 

trust wholly to an accurate and well-practised eye. The 

direction being determined on, the artist must he well 

aware which are the hard points and which the soft ones ; 

the former being those solid angles of the original octahe- 

dron, which it is necessary to cut directly across, and the 

latter those solid angles which are to be obliquely divided. 

A degree of force which may be safely applied, and is even 

requisite in making a section through the former, will be 

very apt to flaw and tear up the laminaB when applied to 

latter. On these accounts it probably is, that the fatiguing 

and even painful process of performing this part of the 

business by hand, is not yet superseded by 

the use of 

machinery. 

" These preliminary matters being settled, the diamond 

is imbedded inâ strong cement, fixed at the end of a stout 

spindle-shaped stick, about a foot long, with that portion 

only projecting, the removal of which is to form the first 

facet. The instrument employed for this purpose is another 

diamond, fixed in a stick similar to the former, with one of 

the solid angles projecting. In order to collect the powder 

and shivers that are detached during the process, the cut- 

ting is performed over a strong box, four or five inches 

square, furnished with a false bottom perforated with ex 

cessively minute holes, in order to sift, as it were, the dust 

from the shivers; and also with two upright iron pegs, 

fixed on the sides, for the workman to support and steady 

his fingers against, while with a short repeated stroke, 

somewhat between scratching and cutting, he is. splitting 

off, or more laboriously wearing away the diamond in that


part where the facet is to be placed. This being done, the 

cement is softened by warming it, and the position of the 

diamond is changed, in order to bring a fresh part under 

the action of the cutting-diamond. When, 

in this slow 

laborious way, all the facets have been placed upon the sur- 

face of the diamond, the cutting is completed. The stone, 

if examined by a moderate magnifier, now presents ragged, 

rough edges; and a broken, foliated surface, with a glistening 

lustre on those facets that are' nearly in the direction 

of the natural lamina?, and on the other facets a more even 

surface, but of a dull opaque grayish-white color. 

" The shape of many diamonds is so irregular, that it is 

necessary to remove pieces of considerable magnitude in 

order to bring them to a form proper for cutting. Where 

the lines of these proposed sections coincide with the 

natural lamellar structure of the stone, the workman has 

recourse to the delicate, and perhaps somewhat hazardous, 

operation of splitting the diamond, by which a double ad- 

vantage is obtained. In the first place, there is a great 

the slices or shivers 

saving of time ; and in the second place, 

are themselves sufficiently large to admit of being cut and 

polished. The method of splitting is made a great mystery ; 

thus much, however, may be mentioned, that when the 

direction in which ^the section is to be made has been deter- 

mined on, it is marked by a very fine line, cut by the 

of another dfamond : the- stone is afterwards fixed 

point 

by strong cement in the proper position, in a block of wood, 

and then, by the application of a due degree of force, the 

section is effected. 

" 

The diamond being thus, by the joint action of splitting 

and cutting, brought to the required form, the next 

object is to polish the facets, and at the same time to 

redress any little inequalities that may have taken place in 

the cutting. The polishing-mill is an extremely simple

fill 

OX GRINDING. 159 

machine, consisting of a circular horizontal plate 

of cast- 

iron, fourteen or fifteen inches in diameter, called a skive, 

suspended on a spindle, and capable of being put into rapid 

motion by means of a larger wheel, five or six feet in 

diameter, and turned by an assistant.. From the centre to 

the circumference of the iron plate, are lines* or shallow 

grooves, formed by rubbing it in that direction with a fine 

serve to retain the mix- 

grained gritstone : these grooves 

ture of oil and diamond-powder with which the plate is 

charged. In order to keep the diamond perfectly steady 

while the polishing of each facet is going on, the following 

contrivance is had recourse to : a copper cup, called a dopp, 

about three quarters of an inch in depth and in width, and 

furnished with a stem about four inches long of stout 

copper wire, is filled with plumbers' solder, which also pro- 

jects in a conical form beyond the rim of the cup 

apex of this cone, the solder being softened by heat, the 

diamond is imbedded with one of the facets projecting. 

The stem of the cup is now put into very powerful pincers, 

which screw up with a nut and a wrench or lever, and thus 

: in the 

hold it perfectly tight. The handles of the pincers (made 

of wood, and called tongs) are broad, and terminate in two 

feet, about an inch high, so that when laid horizontally, 

they are supported exactly as a pair of candle snuffers are, 

the studs fixed to the handles of the snuffers representing 

ing the legs of the pincers, and the single stud near the 

point of the snuffers representing the inverted copper cup 

holding^the diamond is placed on the plate, the pincers rest- 

ing on their legs on the wooden bench or. table that supports 

the plate, and pressing at the same time against an 

upright iron peg ; the broad part of the pincers between 

the legs and the^diajnond, is then loaded with weights, 

both to steady the machine, înd to increase the pressure of 

the diamond against the skive. Matters being thus ad


on the 

justed, a little oil and diamond powder is dropped 

plate, it is set in motion at the rate of about two hundred 

revolutions in a minute, and the process of grinding down, 

and at the same time of polishing, is begun. The diamond 

is taken up and examined from time to time, and is adjusted 

so as to give -the facet its true form. The heat occasioned 

by the friction is at all times pretty considerable, and when 

the pincers are heavily laden, it occasionally increases to 

such a degree as to soften the solder and displace the dia- 

mond. This is a serious accident, frequently occasioning a 

flaw in the diamond, and always tearing up the surface of 

the skive, so as to damage it very considerably. There is 

room on the skive for three or four diamonds at the same 

time ; and to give each its proper share of attention, is as 

much as one person can well manage. The completion of 

a single facet often occupies some hours." 

The polish is often produced by rubbing the diamond 

with a cloth or bare hand. The form which the gems have 

to receive from the lapidary varies according to the condi- 

tion of the stones; and the skill of the artist consists in the 

right selection of a form which shall correspond with the 

natural structure of the gems. A good cut has the greatest 

influence on the lustre and beauty of gems ; the colorless 

and limpid gems, for instance, require a different form from 

those which have a play of colors. With a diamond, the 

form must correspond as much as possible with its natural 

or original shape, in order to save the great trouble of 

grinding, and the waste thereby produced. Transparent 

gems ought not to be cut too thick ; the rays of light 

might otherwise be refracted too much, or prevented from 

penetrating through them at all : in the first instance, the 

lower facets do not act in correspondence#with the upper, 

and the rays are much distributed before reaching the eye. 

Gems of such description are called clotty. On the other

FOKMS OF THE DIAMOND. 161 

hand, if the gems are too thin, their beauty, elements, and 

general 

value are likewise diminished. There is a definite 

proportion of thickness to the breadth of colorless or limpid 

gems, whereas the cut of the colored gems -depends upon 

the intensity of the color. 

POEMS OF THE DIAMOND. 

Diamonds were formerly cut according.to their natural 

form, and mostly in the planes of the octahedron. They 

were called then point diamonds (pierres de nature, oi- 

pointes ingenues). 

The following forms are now, more or less, adopted by 

the Dutch and English diamond-cutters : 

A.. The 3rittiant. This cut displays to greatest advan- 

tage the lustre of the diamond : it may 

be considered as 

obtained by two truncated pyramids, united together by one 

common base, the upper pyramid being much more deeply 

truncated than the lower. It is formed 

a, of the crown, or that part of the 

stone which remains visible after the 

stone is mounted ; b, the collet, or lower 

part ; c, the girdle, 

or the common base 

for the crown and eollet ; d, the table, the plane which is 

formed by the truncature of the upper pyramid ; e, the 

bisel, that space which lies between the girdle and table ; 

and f, the collet-side, the space between the girdle and 

collet. The English lapidaries cut the girdle sharp, where- 

as the Dutch leave it broad : the crown amounts to one 

third, and the collet to two thirds of the whole height of 

the diamond ; the tafole amounts to four- ninths of the 

diameter of the brilliant, whereas the collet only needs one 

fifth of the size of the table. The table and collet are 

regular octagons, and the facets occupied by the bisel are


eight lozenges, with twenty-four triangles, and are called 

the star-facets / the facets occupied by the collet-side are 

four irregular pentagons, alternating with as many irregular 

lozenges, radiating from ^the collet as a centre, and are 

bordered by sixteen triangular facets adjoining 

the girdle, and are generally called the 

pavilion or cro'ss facets. According to the 

number of facets, the brilliants receive their 

either of double or treble brilliant : the 

names, 

double brilliant is surrounded by two rows of 

facets on the bisel, which are . triangular, and 

meet each other the treble brilliant has ; fifty- 

eight planes, fifty-six facets, table and collet, thirty-two 

the star aud 

facets of which are in the bisel in three rows ; 

pavilion facets are triangular, 

the intermediate ones are 

four-sided, -and on the collet-side are twenty-four facets. 

The English double brilliant consists of twenty-four 

facets, table and collet, sixteen 

form of a star in the bisel. 

of which terminate in the 

Brillionets, or half-brilliants, are those diamonds, the 

spread of which is too great in proportion to their depth, 

and the crown is only cut like a brilliant, but the collet-side 

is. wanting. 

J5. The Hose-Diamond has a crown, 

but no collet ;' it is formed of equilateral 

triangles, 

and consists of two rows of 

three-sided facets ; those on the girdle 

are pavilion, and the others star facets. 

But there are variations in the number of 

facets : the Dutch roses have eighteen pavilion and six star 

facets; others have six pavilion aijd six star facets, or 

twelve pavilion and six star facets ; and some, also, have 

twenty-four three-sided pavilion and twelve^ star facets. 

The rose-diamond is only that diamond, the, proportion of

FORM OF GEMS. 163 

whose breadth to its depth is too much extended, and 

which would not, without ranch loss, make a good brilliant. 

There are fragment rose-diamonds, which are very small, 

and ear-drop roses. 

C. The Table-Diamond is that stone which 

is very flat and of little depth, and which re- 

flects but little lastre. They have a table with 

four planes and eight facets, and, in order to 

make the best of their lustre, theyêceive a brilliant cut. 

D. The Bastard-Diamond is that diamond whose cut 

is mixed up from the above forms. 

There are a few more forms given to those diamonds 

which are found unfit for any of. the above cuts, such as 

the thick-stones, the portrait-diamonds, the sen ail-diamonds, 

which are, however, all unfit for the above cuts. 

FORM OF GEMS. 

The gem lapidary occupies himself not only with grinding 

the common and rare gems, but also pastes, &c. He 

uses likewise wheels, but of different material from those 

for-diamonds. His wheels are either of copper, if for very 

hard stones, or of lead or pewter for softer stones ; he has 

likewise polishing wheels. If a wheel is too soft for very 

hard stones, he cuts furrows in it, which are then filled out 

with rotten-stone or tin-ashes ; 

or if very hard stones, such 

as sapphire, .are to be ground, the diamond powder is 

used for the same. Tin wheels are used for hard stones ^ 

water, or oil of vitriol, is used for moistening the wheels. 

The gems (in order to grind them or to give their 

facets) 

are cemented into a handle, at the end of which is a 

composition 

of resin and brickdust. Particular attention 

is required in grinding the colored, gems, as the greatest 

effect may be produced by their "thickness ; pale-colored 

gems require to be left thicker .than darker ones ; 

on the


other hand, they ought not to be left too thick, as they 

will appear too dark, and thereby 'lose, their lustre. The 

same proportion in the manner of cutting the crown and 

collet of the colored gems has to be observed as with the 

brilliant ; namely, the crown ought to be one third and the 

collet two thirds in size of the depth of the whole stone; if 

the gem be of a pale color, the collet ought to be three 

fourths of the size ; and if of a darker color, much less ; the 

table of those colored g^ns which require to be heightened 

ought to be waved somewhat, whereas it ought to be even 

in darker gems. The forms received by the colored gems 

in cutting resemble, in many instances, those of the dia- 

mond; but the following-are the additional ones they receive, 

according to the nature of the shape and color of the 

stone : 

A. The Step or Pavilion cut. The planes, 

which are long and small, decrease towards 

the table and collet, and terminate in steps ; 

the crown has usually two, and the collet four 

or five facets on each side; the form of the 

stones may be of four, six, eight, or twelve sides, or nray 

be long or round. This cut is particularly applicable to 

colored gems, as it reflects the light in a high degree, by 

which the play of color is much raised ; and it is at all 

events to be preferred in the collet of colored gems, even' 

to those brilliants in pavilion : the crown may be of any 

form whatever. 

JB. The Mixed facet cut- is a com- 

pound of Brilliant and pavilion cuts, the 

first being on the crown ; 

it is. a very fa- 

vorite cut for colored gems, and con- 

tributes much in raising 'the lustre.

FOKM OF GEMS. 165 

C. .The Elongated Brilliant facet cut, 

which, if the brilliant facets are on the 

crown elongated, and the collet has a 

pavilion cut, is very appropriate to long 

and thin stones. 

D. The Table cut, having either an uneven or 

conchoidal table, with one or two rows of facets, 

in a circular form, around it : a very useful form 

for seal-stones. 

E. The Double facet cut, the crown hav- 

ing two rows of facets, and the collet the 

pavilion form; this cut is well adapted to 

such stones as require the concealment of 

any faults, flaws, or fissures. 

F. The Cabochon cut, is either flat, convex, or double- 

convex that is, arched ; it may 

be on both 

sides, or only on one. This cut is particularly 

applicable for semi-transparent gems, or those which display 

or 

their peculiar colors, such as the opal, moonstone, &c. ; 

coUect the light 

in a small space, on one or several points, 

according to the convexity they have received. The cabochon 

cut may have one, two, or more rows 

of facets, and opaque stones receive with ad- 

vantage the facets over the whole surface. 

Garnets, for instance, which are generally of 

a dark color, are cut en cabochon, the lower 

plane excavated in a circular form, and the upper plane all 

around with facets. -Other gems, the interior faults of 

which cannot be concealed, may be improved by this cut, 

giving them more transparency, vividness of color, and a 

greater degree of fire. 

A judicious choice of 'the form in which any particular 

gem shah 

1 

be cut, depends on the skill and discrimination 

of the artist.


COMMON LAPIDAKT. 

Such common precious stones as are suitable to be cut 

for snuff-boxes, rings, grinding mortars, seals, and earrings, 

are wrought by the common lapidary, by means of 

copper or iron wheels revolving vertically. The tools are 

generally of iron, and sometimes brass ; some are flat like 

chisels, gouges, ferrules, and some others have coriicular 

heads. The polish is given with rotten-stone, on a tin plate, 

or with crocus martis, on a wooden plate covered with felt. 

The cuts applied by the workmen are either even, cup-shell 

form, excavated, elevated, or quite simple facets are not 

; 

used by him. 

Mr. Mawe describes a lapidary's apparatus, fit for polishing 

minerals, shells, &c., and which may be placed in a 

parlor, where every operation of polishing, on a scale suffi-' 

ciently large, may be effected, and pebbles may be slit of 

three or four inches diameter. It consists of the following 

mills: 

1st. A lead mill, or wheel, to be used with emery and 

water, for grinding down substances preparatory to pol- 

ishing. 

2d. A pewter mill, to be used with rotten-stone a little 

wet, for polishing. 

3d. Tin plate, properly prepared, the edge of which is 

to be used with diamond powder, to slit or cut hard stones 

asunder. 

4th. Wood iriills, covered with leather, &c., for polishing 

marble, alabaster, shells, or other soft substances. 

ENGBAVING. 

The value of many precious stones is increased by en- 

graving them. The common gems have, for several centu-

ENGRAVING. 167 

ries, been used in heraldry. In Italy, Germany, and England, 

we find the coat of arms of distinguished or noble 

families engraved on stone. The machine used for such 

purposes is like that of the i glass cutters, with this difference, 

that finer and harder instruments, and sometimes 

diamond splinters, are required for -this work. Before the 

stone can be cut or engraved, its surface, after having re- 

ceived the proper shape and form required, is rubbed with 

emery,* glass, or leaden wheels. The artist now makes his 

drawing with a brass pin, and executes it afterwards with 

his tools. On hard stones he uses diamond powder ; on 

soft, emery and oil. 

The engraving of armorial bearings, single figures, de- 

vices, &c., on -any gem, is performed by means of a small 

iron wheel, the ends of the axis of which are received within 

two pieces of iron in a perpendicular position, that may or 

may not be closed as the operation requires ; the tools are 

fixed to one end of the axis, and .screwed firm ; the stone 

to be engraved is then held to the tool, the wheel set in 

motion by the foot, and the figure or device gradually 

formed. 

' 

* 

Difficult works are executed after models of plaster of 

Paris, of clay, or other substances ; 

the polish is afterwards 

given on wheels, provided with brushes or with rotten-stone. 

The semi-transparent and opaque stones are more used for 

engraving than the transparent gems, because the drawing 

will not show distinctly through them, on account of the 

great refraction of light ; 

the same is the case with irides- 

cent or shining stones. The engravings are generally bas- 

relief or raised ; those having layers are mostly preferred 

for cameos ; for instance, the onyx, sardonyx, and chalce- 

dony; also wood-opal, which is constantly exported from 

Germany for the'Italian artists in Rome.


SAWING AND DRILLING GEMS. 

Gems and precious stones often require to be sawed in 

different directions, which operation is performed on a 

machine like that of a lapidary, with the exception of a 

polishing plate, for which is substituted a cutting plate 

having sharp ends, or by fastening the stone on a stand, 

and moving continually a fine iron or copper wire stretched 

in a bow, which is moistened with emery and oil-. Care 

has, 'however, to be taken, not to let the stone grow too 

hot, as the heat may crack or make it spotty. The Chinese 

use strings spun over in preference to the wire, they 

having the advantage of keeping the emery sticking to 

them, and of accelerating thereby the operation. For 

drilling gems or other precious stones, a diamond set in 

steel is made use of, to move to and fro by a bow, or the 

common engraving machine, the drilling instrument of 

which consists of an iron point, to which is fastened a diamond 

splinter, which is pressed upon the stone while' it is 

revolving upon the plate. 

GRINDING AND POLISHING MATERIALS. 

The materials for grinding and polishing vary according 

to the hardness of the gem. The diamond powder is ob- 

tained by grinding real diamonds, which are unfit for use, 

with each other in a hollow cylinder of cast iron, in which 

another one exactly similar is used for the most costly and 

the hardest gems. Corundum, sapphire, topaz powder, 

and emery powder, are commonly used for grinding and 

polishing the diamond. It is well to remark that emery is 

often adulterated by a mixture of quartz and oxide of iron, 

or by garnet or iron powder. Emery fit for the use in- 

tended requires to be properly pulverized and levigated.

HEIGHTENING THE COLOR- OF GEMS. 169 

According to Hawkins, the following method is pursued in 

England : The emery is pulverized in an iron mortar and 

passed through different sieves, one finer than the other ; 

the first is levigated with oil, which keeps it in better 

suspension in water ; according 

to the time in which the 

powder settles, the different numbers are obtained. 

For polishing the different precious stOnes, hard and soft 

gems, the diamond powder and emery are mostly used. 

Rotten-stone, tin-ashes, pumice-stone, oxide of iron, English 

jewellers'-red, are all used in their finest pulverized state. 

A great deal depends upon the polish wrhich a gem has received 

all its other ; 

superior qualities being thereby called 

forth. 

HEIGHTENING THE COLOR OF GEMS. 

Since color is one of those characters which is the most 

tempting in the sale of gems and jewelry, ah1 

means are 

ployed for heightening the same, and covering any real 

defect. Foil of small thin metallic substances, colored or 

uncolored, either of fine silver or copper, is placed under 

the gem in the back of the mounting, which heightens the 

color and lustre, particularly of the transparent gems. 

Almost all gems were formerly set in black-colored backs, 

composed of burnt ivory-black and gum mastic, but are 

now mostly set d jour, which is, leaving the lower part of 

the stone uncovered in setting, and only mounting around 

the girdle an old method, and very applicable to perfect 

stones, where no defects require concealment. 

Foiling materially heightens the lustre of gems. The 

rose-diamond al\*ys requires it on account of its flat form. 

There are many gems which would not produce any effect 

without the foil ; it is therefore used whenever a pale or 

impure color is to be raised, or when the'gems are to be 

protected against dust or moisture in order to produce a 

8


uniform shade of color ; the foil forms then a suitable ap- 

plication. 

The coloring of the foil is generally performed by the 

jewellers. Isinglass, first dissolved in water and afterwards 

boiled in spirits of wine, and then strained, is the mass or 

body to which the colors are afterwards added, which are 

also soluble in water. 

For producing a red color, the best material is carmine, 

" 

" 

" 

" 

blue 

yellow 

" 

" 

" 

" 

litmus, 

saffron. 

To produce the different shades and varieties of color, the 

above are mixed in different proportions with each other. 

Very clear stones, such as chfysoprase, carnelian, &c., are 

sometimes painted on the back. The Paris jewellers are 

very skilful in painting stones of inferior value so as to deceive 

even professional men it is for this reason that ; 

gems 

when set ought not to be purchased ; the valuable gems 

which have a foil on their back are mostly set in such a 

manner that they may be examined without the same. 

Foiled gems may likewise be distinguished by holding .the 

table of the set gem on the nail of the thumb and observing 

the passage of light through the crown. 

In the East, rubies are never set with foil, but a cavity is 

made in the lower part and filled with finely polished gold, 

which raises their lustre remarkably. 

Fissures, flaws, or veins, in the interior of gems, are 

mostly concealed by the foil, and when near the girdle, 

are covered by the mounting. 

The defects of stones are sometimes concealed by color- 

ing the case with mastic and ivory-black, find according to 

circumstances leaving blank the spot of the faulty stone, 

or covering only the spot, so as to produce a uniform color. 

Another, and not unusual method of concealing fissures, 

flaws, or other faults, is to cut those stones that have many

SETTING OF GEMS. . 171 

faults the momentary detection of these faults being there- 

by prevented from the play of the refracting light and the 

lustre. The color of many gems is raised by fire, which 

acts in a peculiar manner on them ; thus the. Brazilian topaz 

assumes a very fine pale-red color, by burning. The process 

of effecting this coloring is very simple, viz : after wrapping 

the topaz in a sponge, ignite the same and keep it burning 

until consumed. 

The zircon sometimes assumes a better color after having 

been subjected to a high degree of heat. Amethysts hav- 

ing dark spots may be calcined for a short time in a cruci- 

ble containing sand and iron filings, under which process 

they mostly lose those faults ; but if exposed to an excess 

of heat, they will lose their color altogether, and become 

as white as quartz. 

The Oriental camelian assumes, after 

burning, a fine color, and in Hindostan those carnelians 

which are found detached in the mines are cut up and 

burnt on the spot. Very fine cracks are some.times produced 

in mounting stones, which may be repaired and concealed 

successfully by means of garlic juice. When stones 

are broken by the same operation they may be cemented 

by gum mastic. 

SETTING OF GEMS. 

The gems are generally fastened or set at the girdle in 

a box or rim of metal : limpid and faultless gems are always 

set d jour, i. e., without backs, since they appear 

then to 

the best advantage, and if the gem is intended to display 

its full size and color, the djour setting is only fastened by 

small shanks or claws. The good setting of a gem very 

much increases its value and beauty. The material for 

mounting the limpid gems is silver, which displays them to 

more advantage than gold. In order to increase the color 

or lustre of large gems, they are often surrounded by

1'72 A POPULAR TREATISE ON GEMS. 

smaller gems, such as small roses, rabies, emeralds, garnets, 

turquoise, &c. 

The jewellers' wax used for mounting gems is made of 

three parts rosin, one part beeswax, and four parts fine 

brickdust. 

CLEANING THE GEMS. 

The following composition I have found to be the best 

for thoroughly cleaning gems, particularly when set : Take 

one part flowers of sulphur and two parts of rotten-stone 

or bone-ashes, which, when mixed, is used by it rubbing on 

a piece of buckskin, and with that and a stiff hair-brush, al- 

ternately rubbing the gems, finishing with a softer skin or 

cloth to remove the dust. 

IMITATIONS OF GEMS. 

Pliny mentions the imitation of jewels by glass fluxes, 

and it is sufficiently proved that the ancients were far ad- 

vanced in this art. The Egyptian mummies were provided 

with glass buttons of green an blue color, and during the 

reign of the Roman empire, colored glass was very general ; 

and we find antique cameos carved in various colored glass, 

representing the onyx ; likewise colored glass cemented 

with real onyx ; but they never attained such perfection in 

their art as to set at defiance the skill of the artist and 

jeweller to distinguish between the genuine and spurious 

ones. The imitation of gems may be divided into three 

classes : 

A. The Pastes. The basis of these imitations is a fine, 

pure, and white glass composition, called strass, after its 

inventor, Strass of Strasburgh, in the seventeenth century, 

who first conceived the importance of imitating the real 

gems as respects their hardness, specific gravity, and re-

IMITATIONS OF GEMS. 17*3 

He accomplished the task so far that in 

fraction of light. 

many instances, either all three, or one or the other of his 

objects, were attained. The strass is composed of silex 

(quartz, flint, or pure sand), potash, borax, red lead, and 

sometimes arsenic. To 300 parts of silex add 96 parts potash, 

27 parts borax (prepared from the boracic acid), and 

514 parts of white lead, and 1 part arsenic; or according 

to another method, mix V ounces and 24 grains of quartz 

with 10 ounces and 7J drachms red lead, 3 ounces and 6 

drachms pure pearlashes, 3fJ drachms borax, and 12 grains 

arsenic. The mixture is put into a covered Hessian cruci- 

ble, and kept at a great heat in a pottery furnace for 

twenty-four hours. The longer the mass is kept in a fluid 

state the harder and clearer it will be when turned out and 

cooled. This discolored strass is used by the lapidaries for 

imitating the" diamond, rock-crystal, and white topaz. 

For imitating the colored gems various colored ingre- 

dients are employed. To obtain that intensity- of color ap- 

proaching nearest to the original gem, it is experience 

alone which can guide the manufacturer. In order to imi- 

tate the uniform and intense colors, the strass coloring in- 

gredients are to be of the finest powder, and very intimately 

mixed; the mass is then to be exposed to a very great 

heat, and in that state left for nearly thirty hours, so that 

the cooling may be gradual. Numerous establishments in 

Germany and France are now engaged in the manufacture 

of the strass and colored pastes, each of which possesses 

secrets, acquired by experience, for producing these articles 

in the greatest perfection. 

A. Artificial Topaz. Take of perfectly white strass one 

ounce and six drachms, glass of antimony thirty-seven 

or add to six ounces 

grains, and cassius purple one grain ; 

of strass half a drachm of crocus martis. 

B. Artificial Ruby. This may be obtained, from the pre-

1*74 A POPULAR TREATISE ON GEMS. 

ceding mixture for the topaz by the addition of eight parts 

more of strass, and left for thirty hours in fusion ; when 

taken out and fused before the blowpipe, it yields a most 

beautiful Oriental ruby. Five ounces strass and one drachm 

oxide of manganese may be employed for the same pur- 

pose, but will not make so fine a ruby. Or by calcining 

ammoniacal alum with chromate of potash and lampblack, 

which forms the composition of 

97 parts alumine, 

1 

2 

" 

" 

oxide of chrome, 

silica and lime. 

C. Artificial Emerald. To one pound of strass add one 

drachm of verdigris and fifteen grains crocus martis. 

D. Artificial Sapphire. Add to eight ounces of strass 

fifty-two grains pure oxide of cobalt. 

E. Artificial Amethyst. To eight ounces of strass add 

thirty grains oxide of manganese, twenty-four grains oxide 

of cobalt, and forty grains cassius purple ; 

or to one pound 

of strass, twenty grains oxide of manganese, and one grain 

oxide of cobalt. 

F. Artificial Aquamarine. To six ounces of strass add 

twenty-four, grains glass of antimony, and one and a half 

grain oxide of cobalt. 

C. Artificial Syrian Garnet. To one thousand grains of 

strass add five hundred grains glass of antimony, four 

grains cassius purple, and four grains oxide of manganese. 

Messrs. Bouillette, Hyrclin & Co., Rue St. Avaye; Savany 

& Mosbach, Rue Vaucauson, in Paris; and Henrys & Co., of 

London, have contributed to the great London Exhibition, 

in 1851, a great display of their manufactures in artificial 

stones, such as diamonds, .emeralds, sapphires, and pearls. 

The latter were particularly brought to perfection by Mr. 

Constant Vales, Rue St. Martin,- Paris, 

as the imitation 

pearls by that gentleman were superior to any thing the

IMITATIONS OF GEMS. 175 

author had ever seen before, and were, to appearance, 

quite equal to the natural pearls. 

The following table, taken from Booth's Encyclopedia, 

shows the proportions of the various ingredients for the 

different colored pastes : 

Topaz. Ruby. Amethyst. Garnet. Sapphire. Aq. Mar. Emerald. 

Colorless Paste 1000 1000 1000 1000 1000 1000 1000 

Antimony Glass 

Oxide of Manganese.. 

40 

..25 

.. 

8 

500 

4 

.. 7 

Gold Purple 1 .. >/ 4 

Oxide of Cobalt 5 .. 15 / 

Oxide of Copper .. .. 8 

Oxide of Chrome . . . . .'. Ys 

Colored glass is also very frequently cut in forms and 

shapes so as to resemble gems, and the various colors are 

produced by melting the best qualities of glass materials 

with the folio whig oxides : 

Yellow is produced by charcoal, antimonite of potassa, 

silver, and oxide of uranium. 

iron. 

Blue, by oxide of cobalt, and a mixture of copper and 

Green, by oxide of copper or of chrome, or by antimo- 

nite of potassa, litharge, and cobalt. 

Red, by gold, suboxide of copper, and oxide of iron. 

Violet, by manganese. 

Black, by protoxide of uranium, iridium, platinum, and 

by a mixture of manganese, copper, iron, and cobalt. 

White, by oxide of tin, arsenic, and bone'-ashes. 

By combining one or more of these oxides various shades 

and hues may be obtained ; the yellow glass of antimony 

the use of a little 

may be shaded more into orange by 

oxide of iron ; the purple-red of gold passes into carmine 

the blue of cobalt may be 

by employing silver with gold ; 

shaded into purple by a little gold into ; green by antimony, 

'


or other yellow colors ; a rich grass-green is obtained from 

oxide of chrome, with a little antimony and litharge ; a 

brilliant emerald-green from a mixture of oxide of uranium 

and nickel oxide of nickel alone ; 

yields a hyacinth-red. 

The Bohemian garnet is prepared by fusing together 100 

parts quartz, 150 parts red lead, 30 parts potash, 20 parts 

fused borax, 5 parts crude antimony, 5 parts manganese, 

and 6 parts fulminating gold ground up with oil of turpen- 

tine. 

Turquoise is imitated by oxides of copper 

and cobalt. 

Opal, by adding oxide of tin and bone-ashes to the glass, in 

small quantities. 

The following colored pastes were recommended by 

me twenty years ago, to the American manufacturers of 

colored glass, and have all proved successful : 

JStrass. 

1 

This is the basis for ah pastes ; it is very hard, and gives 

sparks when rubbed on steel. 

1 ounce of powdered glass, 2 drachms burnt borax, 

3 drachms " 

quartz, 40 grains of saltpetre, 

' 

3 

" red lead, 30 

" 

white arsenic. 

This composition is exposed to a white heat in a covered 

crucible for thirty hours. 

I ounce of powdered rock-crystal 

or quartz, 

Ruby. 

3 drachms of red lead, 

15 grains of eassius purple, 

i ounce of dried carbonate soda, 8 " metallic antimony, 

4 drachms of burnt borax, 

8 

" oxide manganese. 

It " 

saltpetre, 

Or by taking 

1 ounce of powdered rock-crystal, 

i " 

dry carbonate soda, 

40 grains saltpetre, 

15 " 

purple cassius, 

80 grains of burnt borax, 

1 drachm of sal ammonia.

Take 

It ounce of ground rock-crystal, 

6 drachms of dry soda, 

2 " " borax, 

Or mix 

1 ounce of rock-crystal, 

" 

y 

dry soda, 

3 drachms " borax, 

" 

It 

red lead, 

IMITATIONS OF GEMS. 

Sapphire. 

2 drachms of red lead, 

1 " 

saltpetre, 

1 grain, of carbonate cobalt. 

.t drachm of saltpetre, 

By means of the carbonate of copper. 

It ounce of rock-crystal, 

6 drachms of soda, 

1 borax, 

Take- 

it ounce of rock-crystal, 

6 drachma of dry soda, 

2 " " borax, 

2 " red lead, 


" 

t 

dry soda, 

2 drachms of dry borax, 

2 " 

. red lead, 

9 drachms of rock-crystal, 

8 

2 

1 

" 

" 

" 

dry soda, 

red lead, 

saltpetre, 

It ounce of rock-crystal, 

t " 

dry soda, 


2 " red lead, 

20 grains of saltpetre, 

Emerald. 

Green Color. 

Canary. 

Chrysoprase. 

i grain of carbonate cobalt, 

15 " " 

copper. 

1 drachm red lead, 

t 

" 

saltpetre, 

t " carbonate of copper. 

1 drachm of saltpetre, 

20 grains of red oxide of iron, 

10 " 

green carbonate of 

copper. 


It 

10 

" 

" 

carbonate cobalt, 

" 

chrome. 

80 grains of oxide of uranium, 

3 " carbonate of copper, 

oxide of tin, 

white b'nt bone-ashes. 

2 drachms of white bone-ashes, 

2 grains of carbonate of copper, 

4 " red oxide of iron, 

6 

" 

oxide of chrome.


Opal. 



8 " 

" 

dry soda, /io 

cassias purple, 

2 " burnt 

" 

borax, Iff 

bone-ashes, 

li 

" red lead, 2 

" 

muriate silver. 

Is ounce of rock-crystal, 

1 

" 

dry soda, 

Aquamarine. 

* 

1 drachm of saltpetre, 

6 grains of red oxide of iron, 

8 drachms of burnt borax, 2 " carbonate of copper. 

2 " red lead, 

Hyacinth. 

The above mixture, with the addition of ten grains of the 

oxide of manganese. 

Garnet. 



8 " 

dry soda, 5 " oxide of manganese, 

2 

" burnt borax, 3 " " 

iron, 

li 

" red 

" 

lead, 1 

cassius purple. 

Rubellite, Red Tourmaline. 


1 

" 

dry soda, 

1 drachm of red lead, 

' 

H " 

saltpetre, 


8 grains of oxide of nickel. 

Indigolite^ or Blue Tourmaline. 

The above mixture, with the addition of the carbonate 

of cobalt. 


2 " 

dry soda, 

14 " 

burnt borax, 

' 

Chrysolite. 

Amethyst. 

1 drachm red lead, 


2 

" 


But 1 grain of the oxide of manganese to each ounce of 

the mass.

IMITATIONS OF GEMS. 179 

Turquoise. 

In the above mixture use instead of the manganese 

5 grains of dry verdigris, 

3 

" 

powder blue, 

Lazulite. 

By adding to former mixtures^ 

2 grains oxide cobalt, 

Agate. 

20 grains of bone-ashes. 

1 drachm of burnt bone-ashef. 

By mixing together several frits and adding oxide of 

iron, several varieties of agate are obtained. 

It will now be necessary to show the distinguishing char- 

acters between the real and artificial gems, as they so 

closely resemble each other that a superficial inspection 

will not always enable the examiner to discriminate be- 

tween them ; they are as follows : 

1. The hardness ; which may be tested on the grinding 

machine ; with fine quartz sand it will immediately attack 

the pastes, or by scratching with a real onyx, to which the 

pastes will immediately yield. 

2. The small air-bubbles in the pastes, may more of less 

be detected with a good magnifying glass. 

3. The cold touch will never remain for any length of 

time on the pastes as it will on the real gem. 

4. The breath remains much longer on the pastes, on 

account of their bad conducting power, than on real gems. 

The specific gravity and electricity, may likewise indicate 

the difference, but I never depended on them alone, and 

I will mention that I once examined the specific gravity of 

an artificial topaz which fully corresponded with that of a 

Brazilian topaz. Electricity will indicate the difference 

between real and artificial gems by the length of its con-


tinuance; for real gems retain, after being rubbed, their 

electricity for from six to thirty-two hours, whereas, the 

artificial ones only retain it from forty to sixty minutes. 

_Z?. The Doublets. This mode of imitating real gems is 

called doubling, when a quartz, cut and polished, is ce- 

mented by means of gum mastic to another colored paste, 

whereby the whole stone assumes the color of the lower 

paste. When a real gem' is employed instead of quartz (as 

the surface and the quartz or paste is cemented below), it is 

called half doubling. This adulteration is carried on to a 

very great extent in the East Indies, where they paste any 

thin gem to a paste corresponding in color. 

The concave doubling is effected by excavating the inside 

of a quartz or paste. The cavity being filled with a colored 

fluid, and the other part afterwards cemented on it, will, 

when well executed, present so uniform a color that it is 

difficult even for a judge to detect the deception. The 

surest method of detection is to put the specimen in question 

in hot water or alcohol, by which the gum mastic will 

be dissolved. When set, the only way of finding out the 

adulteration, is to put it reversely on the nail of the thumb, 

when the false refraction of light or the rainbow colors will, 

with certainty, determine its identity. 

C. The Burning. This mode of adulterating the real 

gems, is performed by coloring cut and polished quartz 

specimens. and throwing them into a solution of permanent 

pigments, such as a solution of indigo, decoction of cochi- 

neal, solution of ammoniacal copper ; the small cavities 

produced by the heat will absorb the fluids. The topaz is 

burnt by itself, with or without the absorption of a pig- 

ment, as also the spinelle, and the quartz ; chalcedony is, 

however, frequently burnt to imitate the onyx, and to en- 

grave thereon cameos and intaglios. 

It 'may be remarked, however, that since the introduc-

GEMS FOB OPTICAL PURPOSES. 181 

tion of colored pastes, very few adulterations of this kind 

are now practised, and we see but rarely such doublets and 

burnt stones. 

PRICE OF AJSD TRADE IN GEMS. 

It is difficult to determine the price of gems without 

reflecting upon all the circumstances relating to them, such 

as beauty and uniformity, the play, the lustre, and the 

vivacity of the colors, and also on the perfection of the cut, 

the polish, the rare locality, the size of the individual gems. 

It depends upon the trade of the various countries whence 

they come, and what quantity of such valuable gems may 

be had at one time at any of the great cities : we find that 

diamonds re often sold at a much less price in London 

and Paris than in Brazil. The principal trade, however, 

is as yet carried on in Brazil and the East Indies, although 

it is in no comparison so prosperous as in former years. 

The gems are sold by weight, as carat and grain-. One 

carat is equal to four grains, and forty-four carats are equal 

to one ounce. The name carat is derived from the word 

kuara, the coral-tree (erythrina), the red pods of which", 

when dry, were formerly used for weighing gold dust, and 

each of them weighs four grains, which is equal to one carat. 

GEMS FOR OPTICAL PURPOSES. 

A few- years ago, Massrs. Trecourt and Oberhauser laid 

before the Parisian Academy lenses of the 

diamond,, 

sapphire, and ruby, which were used in connection with 

were of nine-tenths milli- 

glass lenses in microscopes ; they 

metre, in diameter. The diamond lens magnified two 

hundred and ten times, that of sapphire, two hundred and 

fifty-five times, and that of ruby, two hundred and thirty- 

five times, in linear extension.


A letter was lately published from Sir David Brewster, 

on a curious optical phenomenon that had occurred in the 

construction of a diagonal lens. The diamond, previous to 

working, had all the appearance of internal brilliancy ; but, 

after being polished, it presented a series of stratified 

shades, which rendered it useless for the required purpose. 

It afterwards appeared that lapidaries were acquainted 

with this appearance, which rendered them extremely un- 

willing to take the risk on themselves, of cutting up diamonds 

for optical purposes. On a minute examination of 

this phenomenon, it appeared that these different shades 

occurred in regular strata, each section being about the 

one-hundredth part of an inch, and each stratum having a 

different focus, and being of a different degree %f hardness 

and specific gravity. The inferences drawn from the above 

facts were : that the diamond was a vegetable substance, 

and that its parts must have been held in solution and sub- 

jected to different degrees of pressure at different stages 

of existence. If, on the contrary, as it has been generally 

believed, it is subject to the laws of crystallization, its crys- 

tals must necessarily be homogeneous.

1 Stt.Beiyl. 2 Emerald. 3 Rubeê. ^BrazaTopas. 5 Rulr/. 6 Star 

7 Opal. 8 Hyacinth..

PART III. 

CONSIDERATION OF THE INDIVIDUAL" GEMS. 

DIAMOND. 

DIAMOND: Diamant (German), Adamant (of the an- 

The name 

cients), Almas (Oriental), Diamant (French). 

Diamond is derived from the Greek, Adamas, meaning invincible, 

and referring to the hardness of the gem. The 

Syrians are said to have first known the diamond, and it 

was in early ages the subject of trade to the people of the 

East. The Carthaginians are said to have carried on their 

trade with the Etrurians, who procured diamonds from the 

interior of Africa. Pliny mentions six species of diamonds, 

among which, however, the Indian are to be considered 

the true, in contradistinction to the quartz crystals, which 

were likewise called diamonds in those times. The diamond 

was highly esteemed, and many medicinal virtues 

were attributed to it, particularly against mania, and as an 

antidote for poisons ; it was worn in the rough state. The 

art of cutting it with its own powder was discovered in 1476, 

it was cut in the 

by Lewis Van Berghen. In the beginning 

table-form, with one row of facets on the surface ; afterwards, 

in 1520, the rhomb cut was : adopted the form of brilliants 

was invented in the reign of Louis XII. Cardinal Mazarin 

was the first who had diamonds polished in this form, some 

of which yet belong to the crown of France. For a long


time philosophers vainly speculated as to the nature of the 

diamond ; first it was considered as a mineral, consisting 

of silica ; 

but Newton was the earliest (1675) who expressed 

himself as to the constitution of diamonds. He judged, 

from the great refraction of light, that it must be a com- 

bustible body, and a series of experiments with it, tested 

afterwards by different naturalists, proved the same to be 

pure carjbon. The first trial was made in 1694, by the 

members of the Academy at Florence, by whom diamonds 

were volatilized within the focus of a mirror. Bergman 

first classified the diamond among combustible bodies, and 

mentions having cut off the head of the gems. 

Various views existed in regard to the origin of the diamond 

: some considered it as a secretion of a vegetable 

substance ; 

others as originating from volcanic or plutonic 

revolution. The Indians believe diamonds are continually 

and the inhabitants 

regenerating and growing to this date ; 

of Pharrah, in Hindostan, affirm that the quantity of diamonds 

by no means decreases, but on the contrary, the 

soil will yield a new supply fifteen or twenty years from 

the time it is exhausted. 

Numerous experiments have been instituted to produce 

an artificial diamond from several substances which contain 

carbon, and by the application of a high degree of heat. 

The late Dr. Hare, in Philadelphia, succeeded in melting 

down mahogany charcoal so as to produce a metallic appearance, 

by his deflagrator. Professor Silliman likewise 

made similar experiments with plumbago, which produced 

small globules, some of which were so transparent that they 

could not be distinguished from the genuine diamond. 

Professor Yanuxem, who examined the globules obtained 

from fused charcoal, found them to contain iron and carbon, 

which led him to the conclusion that the charcoal had not 

undergone a real fusion. Cagniard de Latour pretended

DIAMOND. 185 

to have discovered the ingredients for imitating diamonds 

of some size ; but Thenard proved those small crystals of 

the appearance of diamonds to be some silicates of pecu- 

liar composition, which, according to Arago, polarized 

light in a different angle from that of diamonds. All 

speculative experiments to imitate this most precious gem 

by the various compounds of carbon, have hitherto proved 

abortive. 

The diamond is found crystallized mostly in the form of 

an octahedron (composed of t\vo four-sided pyramids, united 

by their bases), or rhombic dodecahedron, rarely of a cube ; 

but the planes of the angles, are often rounded or bevelled. 

The simple octahedron is pretty rare, and still more so the 

cube ; 

but the dodecahedron, either simple or complicated, 

is very frequent ; the crystals are sometimes hemitrope. 

In the museum of tne School of Mines are some fine macles, 

composed of two crystals crossing each other at right an- 

gles. The foliated passages are distinctly parallel 

to the 

faces of the octahedron, in which direction they may always 

be split. The fracture is conchoidal ; surface smooth, often 

rough or striped, and sometimes covered with a scaly 

of an. ex- 

crust; it is transparent, also semi-transparent; 

called the diamond or adamantine 

ceedingly vivid lustre, 

lustre, and when polished, of splendid fire ; 

it is limpid, and 

likewise passing into the greatest variety of shadings from 

white and gray, sometimes from yellow, green, and brown. 

The diamond being the hardest 'of all substances, yields 

to no file ; scratches all other minerals, and is not touched 

by any. This character has become the most important of 

the diamond since the late discovery of the amorphous or 

compact diamond. It is very frequently tinged light-green, 

but more rarely with orange, red, blue, or black ; but' in 

setting, these shades disappear, particularly in the smaller 

but there are also known diamonds of rose and 

diamonds ;


pistachio-nut green colors. The blue color is very rare. 

The blue diamond of Mr. Hope, of London, is one of ex- 

treme beauty and rarity, and is of immense value; the 

yellow diamond in the Museum of Natural History, in 

Paris, is likewise very remarkable for its color and size. 

The black diamond, which is perfectly black, although 

plainly crystallized, occurs most frequently in small bristled 

balls, but crystalline points ; the crystals are very small, 

grouped together in an irregular manner, and extremely 

refractory to the cut ; 

it is considered the hardest of all 

diamonds. The green diamond is also very rare, but I 

have seen some beautiful specimens in the Jardin des 

Plantes and in Freiberg, the first in the cabinet of Abbe 

Hatty, and the latter in the cabinet of Werner. Its streak 

powder is- white or grayish ; 

it becomes phosphorescent by 

the rays of the sun, and electric by rubbing, which property 

it retains for half an hour; its specific gravity is 3'5-3'6 ; 

it does not alter before the blowpipe ; it burns, however, 

at a high degree of heat, and in atmospheric air with a 

bluish flame ; its touch is very cold ; it consists of carbon. 

The diamond bears the same name in trade, but is changed 

according to its cut; the blackish and brownish diamonds 

are called the Savoy diamonds (Diamants Savoyards). The 

compact and amorphic diamond was first brought to notice 

by the experiments of Mr. Dufrenoy, about five years ago, 

as being the transition from the crystallized to the compact 

condition, on account of its hardness and specific gravity, 

and has become a great article of commerce ; it cuts glass, 

scratches quartz and topaz, has a specific gravity of S^V 

3'52, and is completely consumed in oxygen gas; it occurs 

in kidney-shaped and irregular angular masses, but not in 

pebbles ; 

the exterior is generally black, sometimes resem- 

bling the graphite; somewhat resinous lustre, and fre- 

quently its form is very singular, the outside coating being

DIAMOND. 187 

black and resinous, the interior forming a crystalline ker. 

nel, vitreous and lamellar, like the diamond ; 

it is reduced 

to powder, and used for polishing and assisting in the cut- 

ting of the diamond. The largest specimen of the compact 

diamond weighs about 46 carats, and belongs to Mr. Hem- 

erdinger ; 

and a compact diamond in the Museum of Natu-" 

ral History at Paris, weighing about seventeen carats, is 

valued at fifteen hundred francs. The original bed of the 

diamond is not yet known, and on this point opinions are 

much divided. In the East Indies we find it in a conglomerate 

of sandstone, consisting of quartz grains, and disintegrated 

by the ferruginous sand ; and in the mountain chain 

Ralla-Malla, in Hindostan, between 95 and 98 E. L. 

Some of the celebrated diamond mines consist of a breccia 

from argillaceous slate, quartz, lime, and sandstone; the 

boulders and the sand of deserts and rivers yield diamonds 

mostly rounded or in a granular form. The richest diamond 

mines are those of Roalcorda, at the junction of the 

rivers Bimah and Ristna; Golconda, along the shore of 

the Pennar, Sumbhulpra, and Bundelkened, in the neigh- 

borhood of Pannah, where one thousand laborers are kept 

employed. Visapur, Hydrabad, &c., on the island of Bor- 

neo, likewise yield diamonds ; and, according to Jameson, 

diamonds were found in the Indies in the coal formation. 

In Brazil, they were discovered, in 1728, by chance, having 

been always thrown aside with the flint and other 

refuse of the washings of gold, until an inhabitant, who had 

some knowledge of rough diamonds, collected a large num- 

ber, and carried them to Portugal, and acquired by their 

sale a great fortune. Another, who was informed of the 

operations of the first, shared an equally good fortune. 

The government's attention was drawn to the matter, and 

it was declared, in 1730, that all diamonds found there 

belonged to the crown.

188 A POPULAK TREATISE OX GEMS. 

Diamonds are found in the talcose chlorite schist, and in 

a breccia, consisting of ferruginous clay, quartz pebbles, 

sand, and oxide of iron fragments ; and also in a secondary 

bed, accompanied by gold, platina, topaz, beryl, chryso-' 

beryl, tourmaline, kyanite, amatose, spinelle, corundum, 

and garnet. They are found particularly in the valley oi 

Sejues, along the rivers Jequetinhonha and Pardo, which 

run into .the diamond district. These carry most diamonds 

by. The dykes and brooks of the district contain more or 

less rich diamonds, which are found there in recent and 

older beds. Beyond the diamond district, the diamond is 

likewise found in the province of Minas Geraes on the Serro 

de St. Antonio, in the Serro Frio, and in the rivers Aboite, 

Andaja, da Saneno, da Prata, and several other places, 

such as the right bank of the Rio San Francisco, and 

Matto Grosso, and in the beds of Rio Pardo and Rio Vel- 

has ; in the mines of Riven and Cuithe, and all along the 

valley of Peruguado river, in the. province of Bahia, in 

some of the tributaries of the Rio Doce, on the banks of 

the Cachoine. The rocks in which recently diamonds 

have been found consist of the itacolumite, a micaceous 

sandstone, accompanied by mrca-schist, accidentally trav- 

ersed by quartz veins. This is the prevailing rock in the 

Serro de St. Antonio, in which the Jequetinhonha rises in 

the Serro da Matta da Corda, on the eastern slope of 

which the tributaries of the Rio Francisco rise ; 

and in the 

diamond district of Tibagy, very rarely in the alluvials of 

ancient rocks. The gold, diamonds, and other fine stones, 

are always imbedded in the lower part of the alluvium. 

Experience -has shown the richest localities to be in Curranlinho, 

Datas, Mendanho, Cavallo-Morte, and Caxoeira de 

Inferno, Avhere the alluvial soil is from eight to twenty 

feet thick, and is composed almost entirely of silicious 

sand, strongly colored by argillaceous iron, which forms a

DIAMOND. 189 

species of cement of pebbles of quartz, milky quartz, and 

itacolumite, which form a coarse pudding-stone, called 

casoelho, and which is considered by the diamond-washers 

a sure sign of the diamond. Dr. Cliffe, the proprietor of a 

diamond mine in Brazil, has given much information on 

this subject. 

In Russia, the first diamond was discovered in July, 

18^9, by Humboldt and Rose, when on their journey to 

Siberia, on the west side of the Uralian mountains, in the 

gold-washing establishments of Krestowosdwisheaski, belonging 

to Count Schuwalow. The locality, in connection 

with the other circumstances of the place where the diamond 

was found, bears a striking resemblance to the diamond 

district of Brazil. The predominating rock of the 

spot on the Uralian mountains is a quartzose chlorite, talcose 

schist (itacolumite), with an admixture of iron pyrites 

and mica, wherein we find beds of red oxide of iron, talcose 

schist, limestone, and dolomite. In the valley of Poludenka 

and Aedephskoi the diamonds are found among the "debris 

of the mountains, accompanied by quartz, itacolumite, 

brown hematite, talcose slate, dolomite, chalcedony, ana- 

tase, gold, and platina ; it is not yet 

decided to what for- 

mation this rock originally belongs. The production of 

diamonds is twofold; either they are dug out from the 

earth, or they are collected in the sand of rivers. If in 

the latter way, they are more or less rounded, wedged, 

and rubbed off; whereas the former appear coated with an 

earthy, pale gray, yellow, or rose-red, rarely with a blue or 

green crust. Many valuable mines have been relinquished 

in the East Indies since the discovery of diamonds in Bra- 

zil. The locality of the finest diamonds is at present in the 

neighborhood of Sumbhulpore. Two tribes, called the 

Thata and Tora, living in sixteen villages, occupy them- 

selves particularly with searching for diamonds, beginning

190 A POPDXAE TEEATISE ON GEMS. 

in the month of November, and continuing until the L 

mencement of the rainy season, more especially in the bed 

of the Mahanudi on its left shore, where some other small 

rivers, Maund, Reloo, Eeb, &c., empty into it. Four or 

five hundred individuals, consisting of men, women, and 

of the 

children, are examining continually all the spots 

river from Cauderpoor to Longpoor, a distance of about 

one hundred and twenty miles, till the stream is imped'ed 

by the rocks ; 

and likewise all excavations or other cavities 

of the beds where any alluvial deposits may be traced. 

All their implements consist of a pickaxe (ankova), a board 

five feet in length, excavated three inches in the middle, 

but provided with its border (daer), and a smaller similar 

implement, called by them kootla, both of the shape of a 

shovel. The process is very simple : they first dig the 

earth with the axe, and let it accumulate in heaps. along 

the shore; the women afterwards take it on their large 

shovels, and allow the water to run over the earth ; they 

then pick the flints and coarse gravel out of it, and re- 

moving the residue on smaller shovels, spread it out, and 

examine it very carefully, separating from it the diamonds 

and grains of gold. Another method pursued in the East 

Indies is to surround a small plain where the diamonds are 

expected to be found, with a wr all two feet high, under 

which water is permitted to run by -several openings ; after 

having thrown a good deal of earth within the wall, and 

having allowed the water to pass through two or three 

times, the larger stones are picked out, the residue dried, 

and the diamonds selected as before. 

The washing establishments of the diamond in Brazil, 

on the Rio 

particularly in the celebrated district Tejuco, 

San Francisco and its adjoining smaller rivers, are con- 

ducted in the following manner : 

In order to get at the bottom, or soil of the river, means

DIAMOND. 191 

are used for leading the water at a certain spot in a differ- 

ent direction, and then that part of the bed of the river is 

allowed to dry out, and the sediment consisting of a 

conglomerate of .quartz pebbles, kept together by oxide of 

iron, is brought to one place for ' 

washing. It is a large 

bench of triangular form, so as to keep from twenty to 

thirty negroes busy: in the middle of this bench is a 

gutter, with which is connected a trough, inclined some- 

what, in order that the water may run down voluntarily, 

but so that it may be stopped by putting loam at the end ; 

and another gutter with a trough is joined further down. 

The negro who has collected in the dry season a large 

quantity, of the sediment, is occupied in the rainy season 

in putting from fifteen to eighteen pounds at a time into the 

trough, spreading it there, and allowing so much water to 

run over it, until it runs off quite clear from the lower 

trough, but at the same time keeping the trough continu- 

ally moving. He then begins to pick out the larger stones 

from the earthy part, and afterwards the smaller, until 

he comes to grains, which he examines with the greatest 

care, on account of the diamonds. As soon as a negro 

has found one, he must make it known by clapping his 

hands, and the surveyor, who is seated on an elevated 

chair, so that f he can oversee the work, 

posits it in a dish filled with water, 

found during the day are collected. They 

takes and de- 

in which all those 

are then de- 

livered over to the superintendent, who counts and weighs 

them, and enters the result, with other particulars, in a 

book kept for that purpose : 

he keeps them in a bag until 

he delivers them, which he does twice a week, to the gov- 

ernment at Tejuco. 

Every superintendent has to live in the neighborhood of 

the principal washing-establishments, which were formerly 

leased for a certain sum by the government ; but the im-


positions practised were so great, that it took the superintendence 

upon its own account in 1722, and has guarded 

the diamond districts along their lines by strong sentinels, 

who will not allow strangers to pass through .without the 

permission of the general superintendent; 

and even the 

inhabitants, when crossing the line of the diamond districts, 

have to procure written permissions from the above au- 

thority ; and everybody must, on leaving the district, 

submit to a personal and strict examination and search by 

the soldiers ; foot-passengers are always arrested by sen- 

tinels and spies continually on the alert. St. Antonio de 

of the 

Tejuco, forty leagues from Villa Rica, is the capital 

diamond district, and the seat of the superintendence of 

the Junta Diamontina, consisting besides of a confiskal, 

two cashiers, one inspector-general, and a book-keeper. 

Ail the diamonds procured are delivered up yearly to the 

government at Rio Janeiro. 

From four to five thousand negroes were engaged in the 

1818 but one thousand : 

years 1772 to 1775; in the year 

among them were the feitores or surveyors, one hundred 

in number, in the latter year ; likewise ten superintendents, 

whose business it is to conduct the mining department and 

the collection of the diamonds. 

In order to encourage the negroes, presents of tobacco, 

cloth, &c., are awarded, according to the price of the dia- 

the one who finds, for instance, an 

monds which they find ; 

eighth (seventeen carats and two grains) receives his entire 

liberty ; they are severely punished for any offence, and if 

repeated are not allowed to be at this work. Notwithstanding 

the most rigorous regulations and the most watchful 

attention of all the officers, the frauds in stolen diamonds 

are very considerable ; and it is estimated that the smuggling 

amounts to one third of the whole income*. The smugglers, 

who are runaway slaves, examine the most remote parts of

DIAMOND. 193 

the district, or steal the diamonds at night from the work- 

ing establishments ; others, again, who understand it, will 

take the stolen diamonds from the negroes, and devise 

means of escaping with them, either in the soles of their 

boots, or in hollow canes, &c. ; and it is a remarkable feet, 

that all diamonds obtained from the smugglers are inva- 

riably larger 

and more beautiful than those which axe 

brought into market by the government. The thieves 

practise all manner of tricks and impositions, even in the 

presence of the surveyors : for instance, they conceal the 

good diamonds, during the washing hours, between the 

fingers, the toes, in the ears, in the mouth, or in the hair ; 

they also throw them away with other stones, in order to 

often even swallow them. 

pick them up in the night ; they 

The soldier who arrests any smuggler, receives a reward ; 

the property of the latter is confiscated, and he is sent to 

Angola as a prisoner, for upwards of ten years. 

The pure transparent diamond, which is cut in the differ- 

ent forms already mentioned, loses generally one third to 

one half of its original weight by this operation. 

The following table shows the original weight of the 

rough diamonds, and that after being cut ; 

viz, : 

Regent, when rough, weighed 410 carats, and when cut, 136 u /ie carats. 

Grand " " 

Mogul, 780 1 " " 

/., 

279 

" 

/i 

" " 

" " 

Ko-M-noor, 

" 

~186/a 

82"/16 

South " " 

" " 

" 

Star, 

254'/a 

. 124/i 

Nassak, once cut, 

89 3 " " 

" 

/4 

78 10 /i 

It will be perceived, therefore, that the skill of the dia- 

mond-cutter has made great progress in modern times, inasmuch 

as the weight of the Ko-hi-noor and South Star 

was only reduced to one half of the original weight. 

In purchasing rough diamonds, every precaution ought 

to be used to prevent getting false diamonds instead of 

9


real ones, and faulty ones instead of pure diamonds. The 

officers of the Junta Diamontina test the rough stones by 

holding them whilst rubbing together, close to the ear, and 

listening to the tone produced, which gives them ample 

satisfaction of their being genuine, as it is only to be ob- 

served in real diamonds. It requires, however, consider- 

able practice to distinguish them with accuracy by this test. 

Strangers particularly, are imposed upon by the negroes 

in Brazil, by purchasing from them gems cut and polished 

with the facets, resembling those of the diamond; and 

although any one acquainted with the diamond will soon 

detect the imposition by the want of specific weight, the 

peculiar lustre, fire, and hardness, he requires to be on his 

guard. If, however, 

the diamond is ascertained to be 

genuine, we have to examine particularly its purity, color, 

form, and size, these being the qualities by which the price 

of a rough diamond is to be determined. 

It requires considerable experience to determine from a 

of its faults are at the surface 

rough diamond whether any 

or in the interior, whereby often the diamond, in removing 

all its faults, may be diminished to half its size. We often, 

however, judge the rough stones by their color ; those 

turning towards the green 

color are considered to be the 

best ; those of a reddish color to be good stones ; the black 

color indicates a hard stone ; and we judge a yellowish or 

grayish color as making bad diamonds. The natural form 

of a diamond, likewise, gives a characteristic to the pur- 

chaser of rough stones ; 

for a flat, thin, or triangular stone 

would lose much in the grinding, and not be so high as to 

and likewise we are not sure of the 

give it sufficient fire ; 

result of the cutting, and the hemitrope crystals are very 

difficult to work. The best forms of diamonds for cutting 

are the octahedron, which is principally found in the East 

Indies, and is called Pint by the diamond-grinders and the 

;

DIAMOND. 195 

rhombic dodecahedron, which is found principally in Brazil : 

cheese-stones is the name given to amorphous diamonds b} 

the diamond-grinders. 

According to the quality of the diamonds, they are 

divided in Sumbhulpur into four classes, which correspond 

with the deities of the Hindoos the Bramins, Tschettri, 

Wassiers (Bysh), and Tschadrie. The native jewellers are 

very expert in estimating the value of these diamonds. 

The value of the polished diamonds depends on the fofc 

lowing 

conditions : 

1st. Color. The limpid diamonds command the high- 

est price, and twice as much as those that are colored; 

the blackish, brownish, yellowish, brown, steel-gray, and 

impure bluish ones, stand in no value, and are often rejected 

for working. 

2d. Purity, Faultlessness, and Transparency. The Diamonds 

ought to be, according to the technical terms of 

the jewellers, free from ashes, gray spots, rusty or knotty 

places, veins, fissures, scratches, feathers, flaws, sand, grains, 

and faint yellow or vitreous spots. The Brazilian diamonds 

exhibit sometimes, in their interior, designs resembling 

mosses, like those of the Mocha stones and agates ; and we 

may often observe it in the green diamond ; if a limpid 

diamond plays somewhat in the brown* color, it is called 

shrugging, and this diminishes its value : paunched, are 

those diamonds which are neither pure nor clear. 

The transparency and clearness of the diamond are di- 

vided into three degrees, viz : 

A, of the first water, as in those diamonds which are free 

from even the slightest faults, and stand highest in price. 

B, of the second water, as in those diamonds which, 

although clear and limpid, are marred by some dark spots, 

clouds, or flaws. 

C, of the third water, as in those diamonds having ?.

196 A POPULAR TREATISE ON GEMS, 

t 

gray,' brown, yellow, green, Hue, or blackish color ; or 

those that are limpid, but are injured by several material 

faults. 

In order to determine accurately the nature of diamonds, 

lose for a mo- 

it is well to breathe on them, whereby they 

ment their lustre, and the ,eye is then better enabled to 

examine them and distinguish their faults. The real diamond 

becomes clear much sooner than the false. 

3d. The Cut. The perfect and regular cut of the diamond 

increases its value considerably; a brilliant, -for in- 

stance, of one carat, is worth twice as much as a rough 

diamond of equal weight. It depends upon the proportions 

of the height to the circumference of the diamond, and 

that the planes and facets stand in a regular proportion, for 

should this not be the case, the diamond would lose much 

of its fire. 

the price. 

Likewise, the form of the diamond influences 

A brilliant is dearer than a rose-diamond, and 

this is again dearer than the thick and table-stone. The 

facets of the brilliant also influence the price : once cut is a 

brilliant that possesses no cross-facets on the lower part of 

the stone ; 

twice cut, there is one row of facets on the collet 

side; thrice cut, the brilliant possesses the facets on the 

bizel and collet side, according to the rule of cutting. 

The 

more rows of facets a brilliant displays, the higher price is 

put upon it. 

4th. The Size and Weight. The price of a diamond de- 

pends considerably upon- its size ; those diamonds which 

are of great splendor and size are called Paragons' or Non- 

pareils, the Ne Plus Ultra; the less weighty ones are 

valued according to their actual weight. The weight em- 

ployed in Sumbhulpur is the rutta and masha. Seven rutts 

is equal to one mash, and one rutt is equal to two grains. 

In Brazil the weight is specified by carats (quilates). 

Seventeen and a half quilates are equal to one drachm (oc-

DIAMOND. 197 

tava) ; thirty-two vintenes are equal to seventy grains 

one carat is equal to four grains. 

The price of diamonds is determined in trade by exam- 

(graos) ; 

ining accurately their character as above stated, and then 

the price is fixed ; the weight of the diamond is at first 

multiplied by itself, and the sum obtained multiplied again 

by the price of one carat. A brilliant, for instance, would 

weigh two carats, and on examining its properties, if good, 

its price would be found to be forty-four francs. We proceed 

in the following manner to get at the full value of the 

diamond : 2X2X44 = 176 francs. We do not always, how- 

ever, arrive at the correct result. If the brilliants are very 

large, and exceed the weight of eight or ten carats, it is 

difficult to arrive at a standard. I will endeavor to give 

below a table of the prices of the diamond in Holland, 

France, England, Germany, and .the United States, as far* 

as ascertained, and as near to the actual price current as I 

could obtain. 

Rough diamonds fit for cutting 

francs per carat ; any diamond exceeding the weight of one 

are worth ten or twelve 

carat is estimated by the square of its weight multiplied 

by eleven or twelve francs as the average price. 

Brilliants of three grains are in much demand, and are 

worth fifty francs per carat. Those of three carats, used 

for icentre-pieces in necklaces, are sometimes worth four 

hundred francs. Rose-diamonds for mounting, and forty


to the carat, are worth twenty francs the carat ; if r* little 

larger, thirty-live francs per carat. 

Diamonds unfit for cutting, and used by glass-cutters or 

glaziers, are worth from ten to fifteen francs per carat, and 

still smaller ones are worth less ; they are now employed 

by lithographers for their engravings and etchings. 

In 1837, according to Ketot, Pujoux, and Lucas, the 

price 

of diamonds of the first water was three hundred 

francs per carat ; 

Diamonds of one 'grain and less, 

The double cut, first water, 

6 to a grain, 

Of two - 

grains, 

Of three - 

grains, 

Of one - 

carat, 

A diamond of 6 grains, 

10 

12 

15 

18 

and second water, one hundred and fifty, 

'* 

of 6 carats, 

96 francs per carat. 

125 " 

150 " 

170 

" 

- 200 

260-280 

( ' 

- 600 

- 1000 

- 1400 

- 1800 

- 2400 

- 3500 

- 5000 

The abqve prices are from Brard's Mineralogie appliquee 

aux Arts. . 

' 

The price of diamonds (in 1855), according to Mr. 

Achard, 

a celebrated dealer in Paris : 

Glass-cutters' diamonds, less than a grain, 50 francs, or $10 00 per carat. 

Diamonds to reduce to - - 

powder, 

12 " 2-50 

" 

These are the natural diamonds. 

Diamond powder for polishing, 

Compact diamond, called carbonite, 

" in powder, 

Diamonds of 1 carat are worth - 

" 

2 " " 

8 francs, or $1 75 per carat. 

4-6 

" 

1 50 " 

6 " 

1 '50 " 

250 francs, or $50 00 

800 " 160 00 

- 

1,500 

- 

10,000 

" 

" 

SOO'OO 

2000 00

DIAMOND. 199 

According toBarbot, the present (1858) price current of 

diamonds of good quality, and in relation to their weight 

and various forms, is the following : 

A diamond of 1 carat is worth, per carat, 300 francs, or $60 00 

8 grains 

240 

48 00 

210 

42 00 

recut, 8 to the carat, 


A good white and perfect diamond of two carats 

weight is worth from - - - - - 

f 300 to $350 

A 3 carat _______ stone, 500 600 

4 " - 900 1000 

5 " -_--__- 1000 1200 

Spread diamonds, meaning flat stones, so as to display a 

large surface, whereby the collet is shorter than the crown, 

are generally sold much cheaper ; they do not, however, 

display tHeir elements with the brilliancy of a diamond 

having two thirds of the collet and one third of the crown 

in size. 

At a most extensive sale of diamonds, which took place 

in the summer of 1837, at the auction of Rundell & 

Bridges, London, there were twenty-four lots put up, 

which produced the sum of forty-jive thousand eight 

Jmndred and eighteen pounds, nearly two hundred and 

twenty-nine thousand dollars ! Some of the prices were 

as follows : The celebrated Nassak Diamond, which weighs 

three hundred and fifty-seven and a half grains, and is of 

the purest water, was purchased for thirty-six thousand 

dollars. It is. considered to have been sold at a price con- 

siderably under its value. A magnificent pair 

of brilliant 

ear-rings, weighing two hundred twenty-three and a half 

grains, formerly the property of Queen Charlotte, were 

bought for fifty-five thousand dollars, a price infinitely below 

their usually estimated value. A sapphire, seventy-five 

and a half carats, set with brilliants for a brooch, two thou- 

sand four hundred and sixtySve dollars. Brilliant earrings, 

three thousand seven hundred and fifty dollars. A 

brilliant necklace, four thousand three hundred dollars. 

two thousand three hundred and 

Drop emerald ear-rings, 

twenty-five dollars. Brilliant ear-rings, four thousand two 

hundred and fifty dollars. A Turkish dagger, mounted 

with brilliants and rubies, four thousand dollars. A single

DIAMOND. 201 

brilliant, eight hundred dollars. A brilliant drop, seventy- 

nine and a half grains, five thousand nine hundred dollars. 

An oblong brilliant, one hundred fifty-one and a quarter 

grains, fourteen thousand dollars. A brilliant necklace, 

eight thousand dollars. Brilliant ear-rings, twelve thousand 

five hundred dollars. Brilliant necklace, twelve thousand 

five hundred dollars. Brilliant drops, formerly belonging 

to Marie Antoinette, eight thousand eight hundred ancf 

seventy-five dollars. A rose-diamond, eight thousand five 

hundred dollars. A brilliant drop, ten thousand five hun- 

dred dollars. A round brilliant, seventeen thousand five 

hundred dollars. A lozenge brilliant, three thousand five 

hundred dollars, &c. 

Frauds in diamonds are practised by dealers, and the 

purchaser must be guarded. The white spinelle crystal- 

lizes also in regular octahedrons, but is not as hard, and is 

therefore scratched by the diamond. The angle under 

which the light is polarized in either of the other gems is 

very different. 

On comparison with the prices of those now in market, 

it is certain they have much declined, which is partially to 

be attributed to the immense stock which has been brought 

from their native locality. According to Spix and Martius, 

there have been produced in Brazil, from 1772 to 1818, 

in the time of the 

1,298,037 carats of diamonds that is, 

Royal Administration; but that during the Lease, only 

1,700,000 carats were produced, which together make 

2,998,037 carats, or 1301-J- pounds, thus averaging from 

fourteen to fifteen pounds per year ; those brought into 

market by contraband being excepted. The value of the 

above diamonds (8000 reis per carat), produce'd in Brazil, 

amounts to 23,984,276,000 reis, or about 40,000,000 francs. 

This sum bears no comparison to the expense of procuring 

them, since the government lately paid 1 

forty francs fifty


centimes per carat, whereas they only yielded from eight 

een to nineteen francs. On this account the administration 

at Rio de Janeiro has been induced to lease the mines to 

private individuals. Owing to this decrease in the produc- 

tion, the number of laborers is reduced. The richest production 

was in 1784, when 56,145 carats were washed out ; 

and the poorest in 1818, when they procured but 9396 

carats. In Brazil, large diamonds are much rarer than in 

the East Indies, where they are in general of much better 

quality than in Brazil. In the latter country, from 1772 to 

1811, they found but thirty-six diamonds weighing upward 

of seventeen carats, and from 1812 to 1818, but eightythree 

diamonds weighing over eight carats. In the East 

Indies, according to Breton, from the year 1804 to 1818, 

there were found in Mahanues twenty large diamonds, the 

aggregate weight of which amounted to four hundred and 

thirty-six carats and one grain. The largest was found in 

1809, and weighed six hundred and seventy-two grains, 

but was of the third water ; another of three hundred and 

eight grains, and another of two hundred and eighty-eight 

grains. 

As it has already been stated that the artist and amateur 

have to be on their guard against imposition in the purchase 

of diamonds, it may be well to state that there is the one- 

half brilliant, having the form of a brilliant above (the 

or another stone 

upper pyramid), but no lower pyramid ; 

is pasted on by 

stone is readily detected when taken out of the mounting. 

means of mastic. The character of the 

Sapphires, hyacinths, emeralds, and topazes are sometimes 

slightly calcined and sold for diamonds. The first 

two are heavier than the diamond; they are, however, 

. 

harder, and possess more fire. The topaz is distinguished 

by its property of becoming electric when heated, which 

lasts for several hours.

DIAMOND. 203 

Rock-crystal is much lighter, but brilliant and hard ; and 

the same character is applicable to the strass. 

The following list shows the size and weight of the most 

interesting diamonds in the possession 

of different sover- 

eigns. 

The largest diamond is in the possession of the Grand 

Mogul, and according to Tavernier, resembles in form and 

size, half a hen's egg. Its weight is two hundred and 

and three sixteenths carats. It was found in 

nêty-seven 

1552, in the mine 'of Colore, a short distance to the east of 

Golconda, and is valued at 11,723,000 francs. It is cut 

as a rose-diamond, and is perfectly limpid, with the excep- 

tion of a small flaw at the end o"f the girdle. - 

The diamond in the possession of the Rajah "of Mattan, 

carats : it 

in Borneo, weighs three hundred and sixty-seven 

was found on that island." It is of an egg form, has 

a cavity towards the thinner end, and is of the first 

water. 

The Orlow, the diamond belonging formerly to Nadir 

Shah, sultan of Persia, and now in possession of the Russian 

crown, weighs one hundred ninety-four and three 

fourths carats. It is of the first water, without flaws or 

faults of any kind. Its form is that of a flattened oval, 

about the size of a pigeon's egg it formed the eye of a 

Braminian god cut in a pyramidal form ; it is one inch 

three lines in diameter, and ten lines high. It was purchased 

by the Empress Catharine for about ninety thousand 

pounds, cash, and an annuity of four thousand pounds, but 

is considered of more value. 

The diamond in the treasury of^llio Janeiro, was found 

in 1771, at Rio Abaite, by three criminals, who delivered 

it to the government, for which they were pardoned. It 

weighs one hundred and thirty-eight and a half carats. 

The Austrian crown possesses one which weighs one hun-

204 m A POPULAR TREATISE ON GEMS. 

dred and thirty-nine and a half carats, and is valued at one 

hundred and nine thousand two hundred and fifty pounds. 

It is beautiful and well formed, but its color turns towards 

the yellow. 

There is another belonging to the crown, which was 

formerly in the possession of Charles the Bold, of Burgundy, 

who lost his all in the battle of Granson. This 

diamond was at that time the largest in Europe. A 

Swiss soldier, who was the robber thereof, sold it foi^te 

crown dollar to a priest ; 

and after passin-g through several 

hands, it was purchased by Pope Julian II. for twenty 

thousand ducats. 

The Regent, or Pitt diamond, belonging 

to the crown 

of France, is said to have been found in Malacca, and was 

purchased by Mr. Pitt, then governor of Bencoolen, in 

Sumatra, and sold by him to the Regent, duke of Orleans, 

by whom it was placed among the crown-jewels of France. 

It weighs one hundred and thirty-six and three quarters 

carats ; is cut in the form of a brilliant, and is of the first 

water, being absolutely faultless. When rough, it weighed 

four hundred and ten carats, required two years' labor in 

cutting, and is worth, according to the value put 'by the 

commission of jewellers, in 1791, twelve millions of livres. 

It was much admired in the exhibition of Paris, in 1855, 

among the crown-jewels of France. . 

The Sancy, belonging to the crown of France, is one of 

the celebrated diamonds, although not as large as the last 

mentioned, still a very beautiful stone ; it is of a pear-shape, 

is cut as a double rose-diamond of an oblong figure, and 

weighs fifty-six and a %lf carats (thirty-three and twelve 

sixteenths, according to Barbot), and it cost 600,000 livres, 

but is now valued at double that sum. 

A very curious history is attached to this stone, which 

may not be uninteresting to the reader, for its peregrina-

DIAMOND. 205 

tions are wonderful and are well worth relating. 

At first 

it was seen glistening in the casket of Charles the Bold, 

the last duke of Burgundy, who lost it in the battle of 

Granson ; it was found by a Swiss, who sold it to a priest 

for two francs, he resold it for three francs ; it is then lost 

eight of until in the year 1589, King Anthony, of Portu-' 

gal, pledged the same among other stones to M. de Sancy, 

then Treasurer of the King of France, who retained it by 

paying 100,000 francs for it. Henry III., after a lapse of 

time, borrowed it for the purpose of pledging it to the 

S \yiss government, but the servant that was to* convey it 

to that country disappeared, and was not heard of for a 

long time; at last it was discovered that the messenger 

but the faithful servant rather 

was assassinated by thieves ; 

than deliver the jewel to the thieves preferred swallowing 

it. .The spot where the body was interred was discovered ; 

being disinterred, on dissecting the stomach the diamond 

was found. The Baron de Sancy disposed of it to James 

II., while at St. Germains, and from him it fell into the 

hands of Louis XIV. for 625,000 francs, and has ever since 

been the property of the* crown of France. The same 

stone was lost in 1792, with the greater part of the other 

jewels: it "was founcj. again by the police in the Champs- 

Elysees, through an anonymous letter. 

*The Regent, the blue diamond, the celebrated onyx 

known by the name of Abbe Sugen's communion-cup, with 

other diamonds to the value of several millions of francs, 

were then stolen, and but few of them recovered. 

The blue diamond of the crown-jewels of France, is of 

a rich sky-blue color, and weighs sixty-seven and one eighth 

carats; it was valued at 3,000,000 francs, but was stolen 

among the other jewels, in 1792, and not recovered. It is 

said, however, that it was sold in 1835, by an agent of the 

Bourbon family, to a purveyor of the Emperor of Russia,


for the sum of 500,000 silver roubles ; 

since which time it 

has been in the hands of the Princess Paul Demidoff. 

Russia is said to be the richest country for diamonds; 

her crowns are of immense value ; that of Ivan Alexiowitch 

contained 881 brilliants ; that of Peter the Great, 847 ; that 

of Catharine, 2536, and the present emperor has purchased 

for his crown an immense amount of brilliants. 

The Shah-is another of the great diamonds belonging to 

the Russian crown ; 

it is an irregular prism, of fine water, 

and weighs ninety-three carats; it belonged formerly to 

the Emperor of Persia, and then to Nadir-Shah, "and was 

stolen by the revolting soldiers. 

The Polar Star belongs to the Princess Youssoupoff, is 

cut into a brilliant, and weighs forty carats. 

The Prince Esterhazy, as colonel of a fine regiment in 

the service of Austria, Wears, in his uniform of state, a tliamond 

valued at twelve millions of francs. 

The Pacha of Egypt has a diamond cut in facets, which 

weighs forty carats, and cost 700,00'0 francs. 

The Piggot weighs eighty-two and a half carats ; is not 

very fine ; was sold by lottery, in 1801, for 750,000 francs, 

and belonged, in 1818, to the jewellers Rundell & Bridges. 

The Nassak belonged formerly to* the East India Com- 

pany; weighs eighty-nine and three quarters carats; has 

since been recut by order of the Marquis of Westminster; 

weighs at present but seventy-eight and five eighths carats, 

and is valued at 800,000 francs. 

The Holland Diamond weighs thirty-six carats, and is 

valued at 260,000 francs. 

The Hope Diamond, which weighs forty-four and one 

eighth carats, is of a beautiful color like* sapphire ; 

is sus- 

pected of being the same stone which was stolen among the 

French jewels, in 1792. Owing to its beauty it was purchased 

for 450,000 francs, but is worth more.-

DIAMOND. 207 

The Dresden Treasury has a beautiful green diamond, 

like emerald, which weighs thirty-one and one quarter 

carats. 

The value of the crown-jewels of France, has always 

been 29,000,000 franco; among them are comprised 

Diamonds 16,730,203 francs. 

" 

Pearls (506 in number) 996,700 

Colored Stones 

230Kubies , 

134 Sapphires 

-150 Emeralds... 

71 Topazes. 

3 Amethysts (Oriental) 

8 Syrian Garnets 

8 Other fine stones .- 

360,604 

Mounted jewelry 5,834,490 

Ornaments and trinkets 5,144,300 

Total 29,066,487 

The great treasures which were, stolen on the 17th September, 

1792, and not recovered, contained over 1000 

carats of IHlliants and roses of various sizes and qualities. 

In 1810 the Emperor Napoleon L, after purchasing over 

the Continent all the diamonds and jewels which were 

formerly stolen from the treasury, had another inventory 

made out. 

A very black diamond, which belonged to Mr. Papst, 

who sold it to Louis XV 111. for 24,000 francs; it is of 

dark-brown color, but a fine lustre. It came from the 

but it is not known what has become 

collection of Dagni ; 

of it. 

A fine rose-diamond of fifteen carats, in the possession 

of Prince Rioria, at Naples, in 1830. 

Mr. Halphen owned a diamond, in 1838, of twenty-two 

and one half carats weight, of a magnificent and rare 

water. 

"


The Nizam belonging to the King of Golconda, 

is a 

magnificent rough diamond ; it weighs 340 carats, and is 

valued at 5,000,000 francs. 

There are two rough diamonds, belonging to the King 

of Portugal, one of which weighs 215 carats; they were 

found in the river Abayte, which runs 'through the Province 

of Minas Geraes, in Brazil. 

A magnificent pyramidal cut diamond, in Brazil, is 


A rough diamond, found in the river Abatio in Brazil, is 

in the possession of the Prince Regent of Portugal, which 

weighs an, ounce Troy. 

The two large diamonds belonging to the Shah of Persia 

have already been mentioned in the first part, with accom- 

panying figures. 

The Turkish crown has two very large diamonds ; one 

of eighty-four carats, and the other of one hundred and 

forty-seven carats. The latter is valued at eighty thousand 

ducats. 

One found in Brazil, in 1780, weighs seventy-two carats 

and three fourths of a grain. Another, found in 1803, 

weighs seventy carats. They are both at Rio Janeiro. 

The largest of all known diamonds is said to be in the 

possession of the King of Portugal. It was found in Bra- 

zil, in the diamond district, and is as yet in its rough state. 

It is of the size of a chicken's egg, weighing one thousand 

six hundred and eighty carats (above eleven ounces), and 

is estimated in value at fifty-seven million pounds sterling. 

It is now the general opinion of jewellers and mineralogists 

that this is a white topaz. 

The Ioli4-noor, of which there is an exact representation 

on the frontispiece of this work, in its present form, belongs 

to the Queen of England; it is translated as the Mountain 

of Light, and is a very remarkable gem, both for its size as

DIAMOXD. 209 

well as its history. It belonged formerly to the Grand 

Mogul, from whom it passed 

into the hands of the sever- ' 

eigns of Cabal. Runjeet Sing, the king of Lahore, became 

possessed of it in 1813, after a victorious war against 

the Shah Shuja. At the death of Runjeet Sing, t*he East 

India Company took possession of his estates, and this relic 

fell into their hands, and by the latter was presented to 

the Queen of England. Its original weight was one hun- 

dred and eighty-six carats; it was of an elongated form, 

which led to the supposition that iîs a part of an octahe- 

dral crystal ; this opinion has been repeatedly expressed, 

and more particularly by Mr. Tennant, who believes it to 

be a fragment of the Grand Mogul's diamond described by . 

Tavernier. Its awkward shape and bad polish induced the 

queen to have it recut, which was done by Mr. Gaword, 

who gave the Koh-i-noor the form of the Regent Diamond, 

and lost thereby nearly one third of its original weight. 

It is now a beautiful diamond, and is valued at two millions 

of pounds sterling. 

The Star of the South, a Brazilian 'diamond, found in 

July, 1853, is at the present day the largest in Europe, 

coming from Brazil. It belongs to Mr. Halphen, a private 

gentleman, and weighs two hundred fifty-four and a half 

carats ; as a crystal', was a dodecahedron ; it has a specific 

gravity of 3*529. On account of a deep cavity of an octa- 

hedric form, by which it appears to have been attached, at 

a previous stage, to another crystal, it is ascertained by the 

French lapidaries that "this diamond will lose nearly half its 

weight, so that after being cut and faceted, it will weigh 

about one hundred and twenty-five carats, but will still 

rank as a princely diamond. It was found by a negress 

employed in the mines of Begagem, one of the diamond 

districts in the province of Minas Geraes. 

Another large Brazilian diamond was found in the river


Abaite, and is said to weigh about one hundred and twenty 

carats. 

The Nassdk diamond belongs to the East India Com- 

pany, and weighs eighty-nine carats. A beautiful green 

diamond is shown in the royal collection (griine gewolbe), 

weighing forty-eight carats. * 

Among the American diamonds may be mentioned one 

in the possession of Capt. Dewey, having been found in 

Virginia, and a perfect crystal a rhomboidal dodecahe- 

dron, with curved faces, of greenish-white color, and per- 

fectly transparent weighing about twenty-five carats. It 

reflects strongly the light, and has a brilliant adamantine 

lustre. Smaller diamonds have been found in Alabama, 

'three of which belong to Mr. Barnett Phillips of Philadel- 

phia, weighing one,two, and three carats respectively, and 

likewise perfect octahedrons. In Rutherford County, 

North Carolina, a 'diamond of one and a half carats was in 

the possession of Mr. T. G. Glemson. In Hall County, 

Georgia, diamonds have been found several times ; 

in Cali- 

fornia some diamonds are said to have been found. 

The black diamond, which has lately been found in 

Mexico, in the Sierra Madre, is also attracting the attention 

of lapidaries, being harder th#n any other diamond. 

Description of the Crown-Jewels of Queen Victoria Z, 

worn at Tier Coronation, 28th June, 1838. 

The crown in which her majesty "appeared at the ceremony 

of the coronation was made by Messrs. Rundell & 

Bridges. It is exceedingly costly and elegant"; the design 

is much more tasty than that of the crown of George IV. 

and William IV., which has been broken up. The old 

crown, made for the former of these monarchs, weighed 

upwards of seven pounds, and was much too large for the

. DIAMOND. 

211 

head of he? present majesty. The new crown weighs little 

more than three pounds. It is composed of hoops of silver, 

the 

inclosing a cap of deep purple, or rather blue, velvet ; 

hoops are completely covered with precious 

mounted with a bah 1 

stones, sur- 

, covered with small diamonds, and 

having a Maltese cross of brilliants on the top 

of it. 

The cross has in its centre a splendid sapphire ; 

the rim 

of the crown is clustered with brilliants, and ornamented 

with fleurs-de'-lis and Maltese crosses equally rich. In the 

front of the Maltese cross which is hi front of the crown is 

the enormous heart-shaped* ruby, once worn by the chival- 

rous Edward the Black Prince, but now destined to adorn 

the head of a virgin queen. Beneath this, in a circular 

rim, is an immense oblong sapphire. There are many 

other precious gems, emeralds, rubies, and sapphires, and 

saveral small clusters of drop pearls. The lower part of 

the crown is surrounded with ermine. It is, upon the 

whole, a most dazzling and splendid crown, and does infi- 

nite credit to those by whom it has been designed and put 

together. Her majesty has expressed herself highly pleased 

with it. 

The following is an estimate of the value of the 'jewels: 

20 diamonds round the circle, 1500 each "..... 30,000 

2 large centre diamonds, 2000 each 4,000 

54 smaller diamonds placed at the angles of the former. . . 100 

4 crosses, each composed of 25 diamonds 12,000 

4 large diamonds on the top's of the crosses 40,000 

18 diamonds contained in the fleur-de-lis 10,000 

18 smaller diamonds contained in the same 2,000 

Pearls r diamonds, &c., on the arches and crosses 10,000 

141 diamonds on the mound 500 

26 diamonds on the upper cross .'.... 3,000 

2 circles of pearls about the rim 800 

111,000 

The following list of jewelry exhibited at the London


Industrial Exhibition, in 1851, by some French*and English 

manufacturers, comprises but a small part of the im- 

mensely valuable treasures therein collected : The Queen 

of Spain allowed the manufacturer, Mr. G. Lemonnier, of 

The first consisted 

Paris, to show two sets of her jewels. 

of a diamond necklace, in the form of a ribbon, interlaced 

with foliage of emeralds; the stomacher and shoulder 

knots, from which were suspended very large emeralds, 

with clusters of brilliants. A bouquet was formed of lilies 

of brilliants, the leaves of emeralds, and ribbons of brilliants 

with pendants of pearls. The ci'own was in the same style, 

with aiguillettes in the form of flowers, having stamens in 

pearls. The bracelet was likewise a ribbon of brilliants, 

interlaced with emeralds. Another set of jewels, made 

entirely of diamonds and sapphires ; the crown, composed 

in the heraldic style, held in the centre of diamond flowers 

a large sapphire ; and a stomacher and necklace, with a 

wreath of brilliants and sapphire centres, were all scrupulously 

matched, and attracted the attention of thousands of 

spectators while the exhibition lasted. 

The Russian jewellers, Messrs. Jahn & Bolin, of St. Petersburgh, 

exhibited a sparkling diadem, containing 11 

very beautiful opals, 67 rubies, 1811 brilliants, and 1712 

roses. A bracelet of turquoises and diamonds, and a 

brooch in the shape of a knob, composed of 750 turquoises, 

with a pair of ear-rings of small turquoises, 709 in number. 

The English jewellers, Messrs. Hunt and Koskell, ex- 

hibited such a profusion of gems, valued at about two hun- 

dred and fifty thousand pounds sterling, that it would re- 

quire a lengthy description to give but a faint idea of them 

from the rough diamonds of all sizes, by the hundreds, 

to the most exquisite cut and polished gems. A bouquet 

of diamonds, which was as rich as it was elegant, was made 

so as to be entirely taken to pieces, even to the petals of

DIAMOND. 213 

the flowers, for the purpose of cleaning, and for forming 

into seven broaches. They had some particularly beautiful 

bracelets : one in emeralds and diamonds ; another in opal 

and emerald, with white enamel. 

Messrs. R. & S. Garrard & Co., of London, made a sina- 

iiar exhibition of gems and pearls, with a profusion of bril- 

liants and rubies, which would occupy a lull page to 

describe. 

In the collection of Mr. Herz, in London, both in the 

London Exhibition exhibited by Mr. Thistlethwayte as 

well as in his private residence, I examined a very costly 

and unique collection of gems. The diamonds he possesses 

are of every shade and color, such as I have only seen in 

the celebrated Wernerian cabinet at Freiberg, and Abbe 

Haiiy's, at the Jardin des Plantes, in Paris, where they 

were in their natural state, while those of Mr. Herz are 

cut, and many of them set. He had a bouquet of brilliants 

and rubies, valued at four thousand five hundred pounds 

sterling, quite magnificently set ; a bracelet of splendid 

white and large diamonds, and in the centre a yellow bril- 

liant of five carats weight, -which he valued at five thousand 

pounds sterling. 

Messrs. Blogg & Martin, the diamond brokers of Lon- 

don, kindly opened their treasures to me, and my eyes 

were dazzled by three bags, weighing about five pounds 

.each, of diamonds ; most of them cut in the East Indies, and 

weighing from ten to tw'enty carats each. They were not 

put in market, but kept as reserve, and the value of that lot 

could not have been less than half a million pounds sterling. 

I beheld many unique curiosities in hemitrope crystals and 

made diamonds ; many thousand carats of rough crys- 

tals of diamonds, from one grain to twenty carats, all as- 

sorted, in packages, besides the immense valuable supply of 

perfect rubies of ten carats and upward. The scarcity ot


these gems in general, and the high price at which the ru- 

bies were tlien sold in market, formed a very singular con- 

trast while viewing so large a stock in one establishment. 

I only recollect from memory what I saw in 1851, at 

Messrs. Blogg & Martin's ; the sight of so many valuable 

gems had, however, made a lasting impression* on me. 

CORUNDUM. 

The abo.ve name was applied to a different species from 

that of sapphire, but these terms are now generally ac- 

knowledged to be synonymous ; 

not so, however, the em- 

ery, which does not belong to this species. 

Both occur in rhomboids ; often, too, in crystals of sec- 

ondary* form. They scratch all other gems except the dia- 

mond ; their streak and powder are white, and the specific 

gravity is 3*9-4 ; they acquire electricity by rubbing, which 

is retained for several hours ; they are not fusible before 

the blowpipe ; 

with difficulty, by means of borax, they form 

a clear, limpid glass ; acids have no eifect on them ; their 

chemical constituents are alumine, silica, and oxide of iron. 

SAPPHIRE. 

This name is derived probably from the Hebrew, as it is 

often mentioned in the Bible. It is not certain whether' 

the ancients were acquainted with the blue variety only 

of this gem, and were ignorant of other blue stones, such 

as lazulite, fluor spar, &c. It was not used by them as a 

gem, probably on account of the difficulty of working it ; 

but as a medicine, many peculiar virtues were ascribed to 

it. This species has hitherto been usually divided accord- 

ing to its different colors. The name of ruby has reference 

to a red color, and was applied by the ancients to the car-

SAPPHIRE. . 

215 

buncle. Sapphire oc


tre, but it occurs likewise much larger, and is seldom less 

free from faults than any other species of sapphire. 

6th. Oriental aquamarine; greenish blue, pure and 

transparent, possessing a higher lustre and greater hardness 

than the common aquamarine. 

7th. Oriental chrysolite, or peridote; yellowish-green, 

resembling in color the chrysoberyl, but may be distin- 

guished from it by its higher lustre. 

8th. Oriental emerald ; green, more or less dark, inclin- 

ing to yellow ; 

it does not equal in color the real emerald, 

but possesses a higher lustre, and is at the same time very 

rare. 

The sapphires which sometimes display a peculiar play 

of light are divided into 

1st. Star sapphire (asteria, opalescent, or chatoyant sapphire). 

Some translucent sapphires display, if held before 

the sun, or a burning taper, a white light running in six 

rays, resembling three white planes, or stripes crossing 

themselves at one point. This property is thus visible 

when the sapphire is cut convex (or caboehon), and when 

the principal axis of the crystal stands perpendicular to the 

base of the convex cut stone ; these star sapphires are either 

called ruby-asteria, sapphire-asteria, or topaz-asteria, ac- 

cordirfg to the color they bear. 

2d. Girasol sapphire, Oriental girasol, sunstone sapphire, 

or ruby cat's-eye, have a yellowish, reddish, or bluish shine, 

or reflection of light, generally of a lighter color than the 

stone itself, displayed when moved or turned on the convex 

surface. 

Sapphire is composed of pure alumina ; 

the opaque con- 

tains about one per cent, oxide of iron and one per cent, 

silica ; before the blowpipe it is unaltered ; fuses with bo- 

rax and salt of phosphorus, but is not attacked by the 

strongest mineral acids ; friction excites electricity, 

and in

SAPPHIRE. .217. 

the polished specimens the electrical attraction continues 

for a considerable length of time. The perfect and color- 

less Fapphire has a brilliant lustre, so that the same may be 

confounded with the diamond ; its hardness is inferior to 

the latter. The specific gravity of the blue sapphire- is 

3'9V9 ; of the ruby, 3'909 ; of the green (Oriental emerald), 

3-P49; of the violet (amethyst), 3'921. 

The sapphire was well known to the ancients. Pliny 

gave a description of the star* sapphire, under the naine 

of asteria, The sapphire possesses the double refraction 

in an indifferent degree, and its fracture is unequal and 

conchoidal. The finest ruby sapphire occurs in the Ca- 

pelan mountains, near Syrian, a city of Pegu, 

in the 

kingdom of Ava ; also in the sand of the Expaillie river, 

in Auvergne. Blue sapphires are brought from Ceylon. 

Large masses of blue sapphire, of opaque color, have been 

found in North Carolina, as well as some isolated crystals 

in Buncombe County, North Carolina; but there are many 

more localities in the United States, such as New Jersey, 

New York, and Connecticut. Sapphires are mostly found 

in the sands of rivers, or in boulders, with garnets, zircons, 

kyanite, and in basalt. It has been observed that the blue 

sapphires are frequent in Ceylon, but not the rubies, and 

that in Pegu it is the reverse. The most celebrated mines 

of sapphire are at Mo-gaot and Kyat-Pyan, five days' jour- 

ney from Ava. The Boa, or -Emperor of the Birmans, re- 

tains all the larger sapphires. 

For cutting a sapphire an iron mill is used, and for pol- 

ishing, a copper mill, or one made of alloy of lead and tin, 

to which a horizontal motion is given by ajrery simple machinery 

; its surface is charged with diamond powder and 

oil, or with fine emery and water. A thick peg or gauge 

of wood, pierced with small holes in all directions, is set 

close to the mill. The 

upright on the lapidary's bench, 

10


stone, being placed on the surface of the mill, and the op- 

posite end of the stick to which it is cemented being inserted 

in one of the holes of the gauge, the mill is put in 

motion by turning a winch, and the stone kept steady 

on it. 

When the stone has all the facets, the cutting mill is 

taken out and replaced by one of brass, on which the pol- 

and rotten- 

ishing is performed by means of fine emery 

stone, in the same manner as before. A good judgment is 

required in determining the form and proportions best 

adapted to set off any particular stone to the best advantage. 

If the color is full and rich, its transparency perfect, 

and its refractive power considerable, the best form to give 

it is the brilliant. If, on the contrary, the color is dilute, 

the most advantageous method of cutting it is, to cut the 

table side (pavilion) brilliant fashion, and the collet side 

(culasse) in steps ; by this means the table itself will be left 

dark, while all the light reflected from the steps 

under side of the stone will be thrown up into the facets, 

. ! 

on the 

by which the table is surrounded. The French lapidaries 

cut the most perfect sapphires in a square or octagon form, 

with a single delicate -step between the table and the 

girdle, and three or four steps between the girdle 

collet. 

and the 

If the sapphires possess a varying chatoyant lustre, or 

are of a small size, their form is always hemispherical or 

elliptical, without any flat facets; the flatter the ellipse 

the more the varying lustre is diffused over the surface of 

the stone ; 

whereas with a high ellipse it is condensed on a 

single spot. 

In setting samphires we always use foil answering to their 

color. The ruby is set with a reddish gold foil, or a foil 

of copper or red glass ; 

the blue sapphire with a silver foil, 

or blue-colored foil, or with feathers of blue ducks, pigeons,

SAPPHIRE. 219 

or peacocks ; and the water sapphire in a black back : but 

all perfectly pure sapphires are set d jour. 

Many sapphires may be deprived of their specks by a 

careful calcination in a crucible filled with ashes or clay, 

and they assume then a more agreeable and purer color 

and greater transparency. 

Sapphires are very favorite gems, and are extensively 

used by jewellers for setting in pins, rings, &c. In China, 

the ladies'' slippers are mounted with rubies. 

The blue sapphires have 'of late been employed as lenses 

for microscopes with great success. According to Brews- 

ter, it is, for its refracting power, second only to the diamond, 

and superior to all other gems. A new use has 

lately been made of the sapphire for drawing wires it 

being cut in the form of a wedge, through which, by means 

of a diamond-point, a circular hole is drilled and then fast- 

ened on a brass plate; the wire is drawn through the 

smaller aperture of the sapphire towards the wider, by 

which process it is reduced to a thinness never otherwise 

attained. 

The price of sapphires is very relative, but their proportional 

value is next to that of the diamond. The Oriental 

ruby stands highest in value, and when perfect, and ex- 

ceeding three carats, is generally as dear as a diamond of 

equal weight and quality. After the ruby, blue sapphire 

and as this is not so rare, and occurs 

stands next in value ; 

in large specimens, it is not so high in price. Some put 

the price of the blue sapphire equal to that of the colored 

diamonds ; others put the price at half that of a brilliant 

under similar circumstances. Sometimes the value is fixed 

by multiplying half the price of a sapphire weighing a carat, 

with the square of its weight. It is therefore yery difficult 

to come at an exact price-current, and the following aver- 

age prices come nearest to their commercial value :

220 A POPTJLAK TREATISE ON GEMS. 

KUBY. 

Of 1 grain weight 

2 

" " 

3 

" " 

" 

1 carat 

2 " " 

3 

" 

: 

'. 

2 francs. 

5 " 

12 

" 

20 " 

60 

" 

150 

" 

4 " " 250 

" 

5 

" " 

" 

..., '. 350 

BLUE SAPPHIRE. 

1 carat 10 francs. 

2 

" 20 

" 

3 

4 

" 30 

45 

" 

" 

5 

" 60 

" 

6 " 80 " 

8 100 " 

10 

" 

Smaller stones 8 to 1 carat are worth. 

12tol. 

200 

8 

" 

" 

" " " 

16 to 24 

" " 

to 1 

6 

4 

" 

" 

In order to show the various prices of rubies, we cite 

the sale at auction of the Marquis de Dree's collection, at 

Paris 

For a cherry-red Euby of. 2 carats, 1000 francs. 

For a darker Euby of 11 

" 

400 u 

For a bluish-red Euby 

21 

" 

1400 ". 

For a lighter Euby 3 " 

1200 

" . 

For a blue 

" 

Sapphire 

6 

1760 

" 

For an indigo-blue Sapphire 

6* 

" 

1500 

" 

For a light-blue Sapphire 4 " 

123 " 

For a white Sapphire 

41 

" 

400 " 

For an Oriental Amethyst 

11 

" 

400 " 

For a fine yellow Topaz 61 ". 620 

" 

For a 

" 

lighter Topaz 

6* 

71 

" 

There are numerous faults and defects to which sapphiiv 

are subject, and which always influence their price, such as 

clouds, milky or semi-transparent spocks, like chalcedony,

SAPPHIRE. 221 

white stripes, fissures or knots, &c. The sapphire, partic- 

ularly the red and blue varieties, being great favorites in 

commerce, are often imitated, not only by means of other 

colored gems resembling them, but also by substituting 

pastes. .Instead of ruby, we sometimes get the spinelle, 

garnet, hyacinth, red quartz, calcined amethyst, red-burnt 

Brazilian topaz, red tourmaline ; and instead of the blue 

sapphire, we get the disthene, kyanite, and the cordierite, 

hardness is the best test. 

NOTICE OF SOME LARGE SAPPHIRES. 

Tavernier describes two large rubies said to have be- 

longed to the King of Visapur, one of which weighed fifty 

and three quarters carats, and the other seventeen and a half 

carats. The first was valued at sixty thousand francs, 

the other at seventy-four thousand five hundred and thirty 

francs. 

Th'e prettiest sapphire at present in the Imperial Museum 

of France, in Paris, is without fault or defect ; it weighs 

132 T 1 

g - 

carats, and is estimated at 100,000 francs. This 

sapphire was found in Bengal by a poor man who dealt in 

wooden spoons. It belonged afterwards to the mercantile 

house of Rospoli, in Rome, who sold it to a German prince ; 

he again sold it to the jeweller Ferret, of Paris, for 1 70,000 

francs. 

Two great sapphires belonging to Miss Burnett Coutts, 

of London, and valued at 750,000 francs, were much ad- 

mired at the Paris exhibition in 1855. 

The crown-jewels of France contain about 1 50 sapphires, 

of an aggregate weight of 350 carats, and are valued at 

600,000 francs. 

Several sapphires with engravings are seen in Rome, 

such as Hercules ; 

in Turin, in the collection of Genevasio,


of a Tiberius' head, on white sapphire ; 

in St. Petersburg, 

and in the French museum. 

Wahls quotes a ruby of 436 carats and Furetiere saw a 

; 

ruby in Paris of 240 carats ; and Tavernier quotes a ruby 

of half the size of an egg, with the engraving of Scheik 

Sephy. 

The King of Aracan possesses a crystal of blue sapphire 

and Sir Abram Hume possesses a 

of an inch in diameter ; 

distinct crystal of three inches in length. 

The star sapphire on the frontispiece, was formerly in the 

cabinet of Mr. Gilmore in Baltimore. 

The large blue sapphire in Hunt & Roskell's case at 

the London Exhibition, was extremely beautiful, and the 

largest I ever saw. 

The ruby-sapphire of the East India Company, in Lon- 

don, is certainly the largest in the world. 

In the collection of Messrs. R. & S. Garrard & Co., in 

the London Exhibition, rubies were in great profusion 

mostly set with brilliants and pearls. 

The price of rubies depends upon fineness and color; 

they are sold in the United States at from three to twenty 

dollars per carat. 

A fine ruby is worth about the same price as a one carat 

and a two carat stone, if perfect, is worth more 

diamond ; 

than a two carat diamond. 

The King of Pegu and the monarchs of Siam monopolize 

the fine rubies, as the sovereigns of the peninsula of 

India have done the diamonds. 

The finest ruby in the world is in the possession of the 

first ; its purity has passed into a proverb, and its worth, 

when compared with gold, is inestimable. 

The Subah of the Deccan is also in possession of a pro- 

digiously fine one, a full inch in diameter. 

The Empress Catharine, of Russia, possessed one ruby

CORUNDUM. 223 

of the size of a pigeon's egg, presented to her by Gustave 

in., king of Sweden, in 1777. 

Blue sapphires are described .by the English embassy to 

Ava, of the weight of nine hundred and fifty-one carats. 

Mr. Mawe saw a blue sapphire of three hundred and ten 

carats. In the crown-jewels of France, there is one rhom- 

boidal crystal of one hundred and sixty-six carats. 

A beautiful ruby-asteria, in a breastpin, is worn by Mr. 

W. J. Lane, of New York. 

COMMON COBUNDUM, DIAMOND SPAE. 

This mineral was formerly "brought from China only, 

when not so well known as at present, and bore the name 

of common corundum, but it is now considered as belong- 

ing to the general family of corundum. It occurs in crys- 

it has a 

tals, which are generally coated with some crust ; 

conchoidal fracture, is translucent, and has a lustre between 

unctuous and mother of pearl, either gray, red, blue, green, 

brown, or whitish in different shadings. It is mostly in- 

closed in granite, mica slate, dolomite, or magnetic iron, 

and is found in Piedmont, Cananore, Campo Longo, the 

East Indies, and Sweden. 

All the corundums, possessing fine and pure colors, are 

used and cut as jewels, and the impure pieces are pulverized 

and used for cutting and polishing harder stones, or 

glass .and metals, particularly 

so in the East Indies and 

China, and it is called, in Madras, the grinding-spar. 

It may be remarked that the Chinese corundum, which 

is crystallized in prisms of six sides, bears much resem- 

blance to the emerald; the hardness and infusibility of 

both these minerals, and their geological position in the 

middle of old rocks increases their similarity; but the 

emerald cleaves in one direction parallel to its base, while


the corundum cleaves in three directions of its f rimitive 

angles; the emerald has a less specific gravity, as three to 

four ; the phosphate of lime and the tourmaline are also 

found in six-sided prisms; but in all these cases are the 

cleavage, hardness, and specific gravity the distinguishing 

characters. The transparent colorless corundum may be 

confounded with the diamond, topaz, aquamarine, white 

spinelle, and quartz ; in these cases the specific gravity is 

the principal distinguishing character ; the white corundum 

weighs 3*970, the diamond 3 '5 20, aquamarine 2*7, spinelle 

3'64, the topaz 3'4, and the quartz 2'654. 

The emery or granular corundum is of an ash-gray, 

bluish-gray, and sometimog brown color ; is massive, and 

opaque or slightly translucent on the edges ; -is very hard, 

and scratches easily glass and quartz ; is found in a bed of 

talc, in mica slate, in rounded masses, in Naxos, Italy, and 

Spain, and in great abundance on the summit of Gunnechdagh, 

near Gumeschkeny, about twelve miles to the east 

of Ephesus, and betwe'en Eskihissar and Males," in Asia 

Minor, and in Ochsenkop, near Schwarzenberg, in Saxony. 

It has been elaborately described by Professor J. Law- 

rence Smith, of Louisville, Ky., as to its power as a polish- 

ing material. He Jhas ascertained that they all contain 

more or less water, and that their specific gravity as well 

as their hardness depends upon the percentage of water 

therein contained ; but the specific gravity" of a sapphire, 

ruby, or emerald, which contains no water, is.4'06 to4'08, 

and thatihey generally contain from 1*60 to 3*90 per ce'nt. 

of water. This difference does not result" from a decom- 

position of the mineral but from their formation ; 

he proves 

that the presence of water in these minerals which influ- 

ences their hardness or specific gravity, was existing while 

they were on the point of crystallization, and his experiments 

with the emery from China and Asia Minor, have

. 

CHRYSOBERYL. 225 

led him to a scale of hardness to be used in the application 

of emery in polishing the surfaces of certain substances, 

such as a slab of stone, or a plate of 'glass, or any 

other material upon which emery is generally applied for 

polishing. Professor Smith's process consists in the fol- 

lowing method: he reduces the emery to a fine powder 

in a steel mortar, similar to the one the diamond-grinders 

use ; the powder is sifted very fine through a sieve. One 

gramme of this fine powder he employs upon a glass plate 

of 0*10 inch diameter, and by means of an agate pestle 

he rubs the powder circularly and rapidly, until the pow- 

der meets with no resistance and makes no scratching 

noise ; 

the quantity of glass-powder which is hereby taken 

up by the emery gives the index, or the power, of the emery 

under trial. 

CHRYSOBERYL, CYMOPHAIfE. 

The name of this gem is derived from the Greek, and is 

expressive of its color ; it is also called cymophane. It 

was formerly classed with the beryl family, but was separated 

from that by Werner. 

It occurs, crystallized, in a prismatic form, 

also in boulders and grains ; is transparent 

to translucent, and possesses double refrac- 

tion in a high degree ; its lustre is between 

unctuous and vitreous ; exhibits trichroism ; 

fracture conchoidal; its color asparagus 

and olive green, with a tinge of brown, 

yellow, gray, or white. Some specimens 

display, sometimes, a milky or bluish-white 

lustre. Chrysoberyl scratches topaz and 

rock-crystal very distinctly, but is attacked by sapphire ; 

the streak-powder is white, specific gravity, 3*6S 3'75 ; 

JO- 

Fig. 4.


hardness, 8*5. It becomes electric by rubbing, 

and le- 

tains this property for several hours : it is infusible by itself 

before the blowpipe, but is slowly fusible into a glass bead 

with borax. Its component parts are alumina, silica, and 

glucia, 

with some oxide of iron and titanium. In com- 

merce, chrysoberyl is called Oriental chrysolite, 

and that 

Mr. Ebel- 

displaying lustre is called opalescent chrysolite. 

man has produced, artificially, the chrysoberyl from its in- 

gredients. 

Chrysoberyl is mostly found in loose crystals 

or in. 

boulders in the sand of rivers associated with other gems, 

such as spinelle, sapphire, topaz, beryl, &c. In Brazil, 

particularly in the diamond district, and more frequently 

in Termo Minas Novas, Pegu, Ceylon, and Siberia: like- 

wise in Connecticut (at Haddam),- and in New York (at 

Saratoga), imbedded in coarse granular granite, and ac- 

companied by garnet and beryl. 

The chrysoberyl is cut on a brass wheel with emery, and 

polished on a pewter wheel with rotten-stone ; it is very 

often cut in cabochon and, if perfectly pure and transpar- 

ent, in other respects, is set with gold foil, and used for rings 

and pins. 

The chrysoberyl is in no great estimation, on account of 

its indifferent fire and color, but those specimens that take 

a high polish, and occur transparent and pure in color, and 

it is particularly worn 

of varying lustre, are of some value ; 

in Brazil. At Paris a chrysoberyl of fine green color, oval- 

cut, seven lines in length, and five and three quarters in 

breadth, was sold for six hundred francs ; and a very fine 

opalescent chrysoberyl nearly five lines long and four broad, 

cost six hundred and three francs. 

For chrysoberyl have been substituted apatite, fluor spar, 

and pastes.; but it is harder than any of these substances. 

Chrysolite bears a great resemblance to chrysoberyl in its

SPIXELLE. 227 

external appearance, but is much lighter and softer. A 

green chrysoberyl was found in Termo Minas Novas, which 

weighed sixteen pounds, the largest known. It is in the 

possession of the government at Rio de Janeiro. 

SPINELLE. 

This gem was called by the ancients, carbuncle. It only 

occurs crystallized, and mostly in the form of an octahe- 

dron, and its modifications. The crystals are smooth, 

solitary, or grown together as hemitropes, loose, o.ften 

rounded like grains (figure 5 is 

a made form of the spinelle ruby) ; 

its fracture is conchoidal ; 

it is 

transparent and translucent ; it 

possesses simple refraction of light ; 

is of a highly vitreous lustre ; 

and 

its color is red, turning into the 

greatest variety of shadings of 

blue, brown, and yellow. We 

find, likewise, blue, black, and 

green spinelles, which, however, have no commercial value, 

on account of their impure color and want of transpa- 

rency. 

Spinelle scratches quartz, and is attacked by sapphire ; 

becomes electric by rubbing; its specific gravity =3*5 2 3, 

hardness= 7*56 ; is infusible before the blowpipe. Accord- 

ing to Berzelius, the spinelle of Ceylon when heated, grows 

first brown, then black, and then opaque, which, on pooling, 

passes into green and limpid, and ultimately into its origi-* 

nal red. Acids do not affect it ; its component parts are 

magnesia and alumina. The spinelle is classed by jewellers 

and lapidaries according to its various colors. 

1. Ruby spinelle, or spinelle ruby; of a light 

or dark


red, and no milky lustre ; shows, if held near the eye, a 

tinge of rose-red color. 

2. Ruby balais, or balais ruby; pale-red or rose-red, 

sometimes with a tinge of brown or violet. 

3. Almandine ruby ; of a cochineal-red color, bordering 

on blue, violet-blue, and reddish-brown. It is distinguished 

from the garnet, likewise called the almandine, by its lighter 

color, stronger lustre, and greater hardness. 

5. Goutte de Sang is a fine cochineal or blood-red. spinelle. 

Spinelle is found in clay, and in the -sand of rivers, with 

sapphire, garnet, tourmaline, and other gems. The red 

variety occurs in isolated crystals and grains, in alluvial 

soil, and in the sand of rivers Ceylon, Ava, and Mysore 

also imbedded in gneiss and granite, in Ceylon ; the blue 

varieties occur imbedded in granular limestone at Aker in 

Sweden, Rohleta and Lojusoken in Finland, Straskau Mo- 

ravia, in the dolomite of Nalande, and Candi in Ceylon ; 

the white variety is found at La Ricia, near Rome, with 

black garnet and green augite ; the grass-green variety 

(chloi'ospinelle) is found in the chlorite slate of Slatoust, in 

the Ural. The black and brown varieties have numerous 

localities ; 

those from Orange county, New York, are very 

large and perfect octahedrons : one in my possession was 

twelve inches in diameter. Spinelle is cut on an iron or 

brass wheel, with emery or pulverized diamond, and is 

polished either on the same or on a copper wheel, with oil 

of vitriol. 

Spinelle is cut in the same form as the diamond, and is 

set wit^ a foil of copper or gold. Its color is often .made 

%iore intense, and its faults, such as flaws and specks, re- 

moved, by calcining it carefully. 

Lustre, color, and hardness have made the spinelle a 

very favorite gem, which is used in a great variety of 

ways, as in rings, pins, necklaces, &c.

TOPAZ. . 229 

The price of spinelles it is difficult- to determine with 

accuracy, as much depends on their properties ; if perfect 

and exceeding four carats, they are usually worth half the 

price of diamonds equally large. The spinelle ruby and 

balais ruby are the most esteemed spinelles, and if of 

twenty-four to thirty carats, are worth from two hundred 

to four hundred francs ; and such gems are often sold for 

true rubies (sapphire). 

Zircon is of greater specific gravity and less hardness 

than the spinelle, and shows strong and double refraction 

of light. Calcined topaz is distinguished by its electric 

Burnt amethysts are lighter, and are scratched 

properties. 

by spinelle. Pastes are likewise substituted for the spinelle, 

such as glass colored with gold-purple but as ; the spinelles 

are always harder and heavier, the adulterations may soon 

be detected. 

According to Mr. Ebelman, the artificial spinelle is obtained 

by the following mixture, which is put into a platina 

capsule and exposed to the heat of a porcelain furnace : 

Alum, - 6 

grains. 

Magnesia, 

Fused boracic acid, 

Oxide chrome, 

TOPAZ. 

3 

- 6 

" 

" 

O'lO to 0*15. 

It is not determined whether the ancients meant by 

topaz the same gem as we describe, since the Greeks understood 

the topaz to be of a transparent gold-yellow, and 

the Romans, of a transparent green-yellow. The name, 

which, according to Pliny, is derived from Topazos, an 

island in the Red Sea, has no reference to its color. To- 

paz was, in former times, thought to possess great medicinal 

virtues; for example, as a remedy for mania, and as a


strengthening medicine. The topaz occurs crystallized in 

a rhombic prism, but mostly in very complicated forms, 

particularly the Brazilian, Siberian, and 

Saxonian : it is often found in boulders. 

Its fracture is conchoidal ; it is transparent 

and translucent ; possesses some 

double refracting powers ; a very vivid 

vitreous lustre ; clear, straw, sulphur, 

wine, and gold yellow colors, sometimes 

with a tinge of violet-blue, greenish, and 

white. Topaz scratches quartz distinctly, 

but is attacked by sapphire. Its streak- 

powder is white ; specific gravity, 

3*49 to 

3 '5 6 ; it is phosphorescent when heated, 

Fig. 6. 

with a bluish or yellowish lustre,* in small fragments. It 

becomes electric either by rubbing, heating, or by pressure, 

and retains the property for more than twenty-four hours. 

Before the blowpipe, at a strong heat, it is covered with 

many small bubbles, and partly loses its color. It is dis- 

acids 

solved, fusing slowly with borax, into a white bead ; 

have no effect upon it. Its component parts are alumina, 

silica, and fluoric acid. 

In commerce, topaz is distinguished by the following 

names : 

1. Water clrops, pebbles (gouttes d'eau), clear, limpid. 

2. Siberian topaz, white, with a bluish tinge. 

3. Brazilian topaz, gold-yellow, withâ 

4. Saxon topaz, pale wine-yellow. 

5. Indian topaz, saffron-yellow. 

6-. Brazilian ruby, light rose-red. 

7. Brazilian sapphire, light-blue. 

touch of red. 

8. Aquamarine, sea and mountain green. 

Topaz belongs to primitive rocks, and is found in chlorite 

slate, gneiss on gangues, argillaceous schist,

TOPAZ. 231 

zil, it is found in a decomposing chlorite slate (and is there 

called malacheta), within brown hematite cavities or quartz 

gangues, which are of one inch to one and a half feet thick, 

and are overlaid by indurated talc and white and brown 

kaolin, and sometimes intermixed with quartz crystals 

and* micaceous iron, which are the surest indications of 

topaz. Such topaz localities are at Villa Rica, Capao, and 

Lana. Little attention is paid during the dry season to 

the digging of topaz ; but with the beginning of the rainy 

season, the searches for topaz are undertaken, and the 

operation for washing and procuring them is performed 

like that of the diamond, mentioned under its proper 

head. 

In places where the topaz is found in company with tin 

ore, it is picked out ; but where it forms a part of the rock, 

it is wrought by mining operations, as in Saxony. 

Topaz is cut on a leaden wheel, either with emery or pulverized 

topaz, and is polished on a copper wheel with rottenstone. 

Care has to be taken in slitting the foliage. The 

forms which it is to receive depend upon its qualities and 

purposes. The white topaz is cut in brilliant form, with a 

small table ; the bluish topaz, however, is cut with a mixed 

form, but it is to be observed that the table side requires 

to be higher than usual, the. table smaller, and the collet 

side, with its steps, must be attentively wrought in propor- 

tional distance. The yellow topaz is mostly cut as brilliant 

or table-stone, and in setting, its back is supplied with a 

gold foil, and the pale with a red-colored foil. Many spe- 

cies of topaz are set d jour. Topaz assumes, by calcining, 

a different color, and also by coloring fluids, as stated in a 

former chapter. % 

The topaz is in general use by jewellers for setting in 

lings, pins, ear-rings, seals, or necklaces. Its fragments 

are pulverized and used for grinding the softer precious


stones ; 

this is effected by calcining them first, then throw- 

ing them into water, and afterwards pulverizing them. 

By heat the topaz assumes a pink or red hue, so nearly 

resembling the balais ruby that it can only be distinguished 

by the facility with which it becomes electric by friction. 

Topazes from New South Wales, Brazil, and Scotland, 

sometimes contain cavities, in which Sir David Brewster 

discovered two fluids, one of which has an index of refrac- 

tion=l*211, and expands 0*25 of its original vo.lume on 

being heated, from 10 to 27. 

The topaz is found green, blue, and colorless at Ala- 

baschkka Meersinsck, Miask, and Adum Tschelon in Sibe- 

ria ; Kamtschatka, Peru, and Rozena in Moravia, with lep- 

idolite ; Mucla in Asia Minor, Peneg in Saxony, and at 

Schneckenstein, near Auerbach, in Saxony, of a wine-yellow 

color; at Villa Rica, in Brazil, of a deep-yellow color; 

with tin ore at Geyer, Ehrenfriedersdorf, and Altenberg 

in Saxony, Schlackenwald in Bohemia; with tin ore and 

apatite in veins of granite at St. Michael's Mount and Huel- 

in granite in the Morne 

kirid, near St. Agnes in Cornwall ; 

mountains in Ireland ; in the United States, at Trumbull 

and Middletown, Connecticut. 

The less transparent variety (pyrophysalite), with fluor 

in granite veins, at Tinbo, near Fahlun, in Sweden ; 

in bouX- 

ders at Braddbo, in Sweden ; in gneiss at Fossun, in Norway. 

Topaz is generally of less value now than formerly, owing 

to the yearly supplies obtained from Brazil, which is about 

forty pounds. The mine at Capao has yielded about twelve 

thousand dollars' worth, and the supply has been accumu- 

lating at Rio de Janeiro and Bahia to such a degree, that 

it is disposed of at^ less price there than at the mines. 

Those most esteemed are the rose-red and the white, or 

water drops, pingos cFagoa. A topaz of the size of a bean 

is sold at Chapada, in the Termo Minas Novas, at one

TOPAZ. 233 

dollar ; one of one carat is disposed of at an average rate, 

for eight dollars; a yellow one for three dollars; and a 

yellow burnt one for five dollars. In Brazil, very large, 

* 

fine, and lustrous ones, bring thirty dollars. 

The Saxonian topazes are less valued, yet good yellow 

or crimson colored ones, nine lines long and seven broad, 

bring four hundred and twenty francs. 

Aquamarine and chrysolite are sometimes substituted 

for topaz; but it may easily be distinguished from them, 

not only by its hardness, fracture, and specific gravity, but 

more especially by its property of becoming electric by 

rubbing. This will prevent, the substitution of either of 

the above, or those most resembling them; such as the 

yellow quartz, chalcedony, or other yellow-colored stones. 

According to the account of Tavernier, the Grand Mogul 

possessed an octangular polished topaz of one hundred and 

fifty-seven and three quarters carats weight, which has been 

purchased for sixty thousand dollars. 

M. d'Eshwege notices- a topaz crystal ten inches in length 

and four inches in diameter. The United States (Connect- 

icut) yield topazes of an opaque color^ pale, dark orange, 

and yellow, twelve inches in length. One of the finest 

Brazilian topazes I have seen is in the rare collection of 

Robert Gilmore, Esq., of three inches length, and perfectly 

terminated. The Brazilian topaz on the frontispiece was 

exhibited in the London Palace by Mr. Tennant. Some 

very splendid cut Oriental topazes I saw at *Mr. Stephen 

H. Palmer's; they were of wine-yellow color and good size. 

In the French Imperial Bibliotheque there are several 

engraved topazes Philip II. and Don Carlos in white 

topaz, and engraved by Jacques de Trezzo ; and in a very 

large and deq) yellow topaz, an Indian Bacchus, in the 

Vatican. The House of Orleans had a Mercury seen in 

profile, on ah Oriental topaz, with eight facets.


In Turin, in the Generosio collection, was a topaz in- 

taglio, representing Victory in a chariot drawn by two 

horses. 

Caire possessed an Oriental topaz of twenty-nine carats, 

pierced lengthwise, with the following words in Arabic let- 

ters : "God only will accomplish." It was an amulet, 

known by the Arabs as gri-gri. 

The ancient rona&v was found on an island in the Red 

Sea, which was often surrounded with fog, and therefore 

difficult to find ; it was hence named roTraâ, to seek. This 

name, like most of the rnineralogical terms of the ancients, 

was applied to seyeral distinct species! Pliny describes a 

statue of Arsinoe, the wife of Ptolemy Philadelphus, four 

cubits high, which was made of ronafrv, but evidently not 

the topaz of the present day, nor chrysolite, which has 

been supposed to be the ancient topaz. It has been con- 

jectured that it was a jasper or agate ; 

it to be a prase or chrysoprase. 

. EUCLASE. 

others have imagined 

Monoclinohedric figures ; cleavage clinodiagonal, highly 

perfect, very brittle and fragile ; conchoidal 

fracture ; hardness, 7*5 ; spe- 

cific gravity, 3* ; transparent ; splendid 

vitreous pale mountain-green, passing 

into yellow, blue, or white. When 

heated befor^ the blowpipe, it intu- 

mesces, and melts in thin splinters to a 

white enamel; is not acted upon by 

acids; is composed of 44'7 silica, 31*8 

alumina, and 23'5 glucine, with 1 to 

2-2 peroxide of iron, and 0*4 to 0*7 

oxide of tin. It is found in chlorite 

slate at Boa Vista 'and Capao, near

EMERALD. 235 

Villa Rica, in Brazil ; in Peru, and is said to have been 

found in Siberia. It is very rare, and for this reason not 

much used as 'a gem ; it resembles much the aquamarine 

when cut. 

EMERALD. 

The emerald proper and the beryl belong to this mineral 

species, and are distinguished by their color and crystalline 

form. The emerald occurs in six-sided prisms with their 

modifications; it scratches quartz, and is scratched by 

topaz. The streak-powder is white ; its hardness is 7*5 to 

8*0 ; specific gravity, 2'73 to 2'76 ; it becomes electric by 

rubbing ; 

it is rounding before the blowpipe, 

and forms an 

opaque black, but becomes a green or limpid glass, having 

the hardness of borax. Its constituents are glucia, alumina, 

and silica. 

THE EMERALD PROPER. 

The emerald appears to have been known in the most 

remote ages, and was the third stone, according to Cal- 

met's arrangement, on the high priest's breastplate of judgment, 

with the name of Zebulon inscribed on it. In the 

time of Pliny, this stone was held in such high estimation 

that it was seldom if ever engraved upon. The moderns, 

however, did engrave on the same, as we find in the royal 

collection at Paris a head of Henry IV., and one of Louis 

XIV. It has been excavated from the ruins of Rome, and 

from Herculaneum and Pompeii. But the ancients often 

included under this name other gems of the same color ; 

such as the green fluor, aquamarine, jasper, malachite, &c. 

They appear to have' obtained the emerald from Egypt. 

Cailloud has in modern times succeeded in finding the old 

emerald mines in the Theban deserts,' on the Arabian Gulf 

which have been noticed by the ancient authors, and by


the traditions of the Arabs, as coming from the mountains 

of the Sahara when sent on an exploring expedition by 

the Pasha of Egypt. He mentions having found subterra- 

nean mines, capable of allowing four hundred men to work ; 

and he likewise found tools, ropes, lamps, and other uten- 

sils. He, judged from the ruins of the architecture of the 

temples of a city which he discovered, that- they were of 

Egyptian or Grecian form, and about one thousand years 

old. 

Among 

the church treasures of the ninth and tenth centu- 

ries, we find the emerald, which came into particular notice 

after the conquest of Peru, where an emerald the size of 

an ostrich egg is said to have been idolatrized by the savage 

inhabitants. The' emerald was formerly used as medicine, 

and was worn "as a preventive against epilepsy. 

The emerald occurs in somewhat depressed 

six-sided prisms ; the lateral faces of which are 

smooth ; the fracture is conchoidal to uneven ; 

it is transparent to translucent ; displays double 

refraction in a slight degree ; has a vitreous 

lustre; is green and emerald-green 

different shades. 

with its 

According to Mr. Ebelman, the true emerald is prepared 

artificially by 

Silica - 7* grains. 

Alumina - 1*60 

Glucia - 1-40 

Fused boracic acid - 4*06 

Oxide chrome - O'lO 

It is scratched by an English file, and scratches strongly 

white glass, and slightly quartz. Its specific gravity is 2*73 

to 2*77. Its color is owing to the oxide of chrome. An 

emerald when calcined, and thrown into water, crumbles 

" 

" 

" 

"

EMERALD. 237 

into pieces of different colors. The purest emeralds are 

called the Peruvian. 

The emerald is found in micaceous schist at Salzburg, in 

the Sahara mountains, in gangues in Peru, in the argillaceous 

and in hornblende slate. Formerly, the finest 

emeralds came from Warta, in Peru; but the mine is 

either exhausted, or the Indians filled up "the mines before 

they left them at the conquest. The best are now found 

in the valley of Tunca, in Santa Fe, where they occur in 

granite. The emerald has lately been discovered in Siberia, 

in the micaceous schist, and is equal to the Peruvian in 

every respect. 

The emerald is sawed into pieces with emery, cut on the 

copper wheel, and polished on a. finer wheel with rotten- 

stone, pumice-stone, tin-ashes, ancl water. .The step-cut, 

and the mix^d step-cut, or the table-cut, are mostly used, 

yet it is sometimes cut as a brilliant or rose-cut. They are 

set with a green foil or green satin on their back ; *or some- 

times in a back colored with mastic, and very black ; but 

if perfectly pure, and of fine color, they are set djour. On 

exposure to air, emeralds grow by degrees paler. 

The* emerald is, on account of its agreeable green color, 

a very favorite ornament, and is . used' for the most expen- 

sive kinds of jewelry. Its value' depends altogether ûpon 

its pure and fine color, vivid lustre, and the size of the 

specimen. The price of emeralds was much higher before 

than it has been since the discovery of Mexico ; the prod- 

uct of the mines of Pern reduced their price considerably; 

now they are getting dearer again, and always command a 

good price. A small box of fair 'emeralds from Peru, 

which I saw a few. years ago, at the oifice of the American 

and Foreign Agency, in this city, which ^weighed from 

three to four pounds, was sold afterwards at Paris for nine 

thousand francs. A good emerald, of fine color, is worth


twelve dollars per carat ; 

to its intSrior. qualities. Jhe price 

and the price increases according 

of the best emeralds of 

4 grains is 18 dollars. 

8 

16 

24 

48 

" 

30 

" ... 200 

" ... 300 

. 

" 

'1000 

Good emeralds, meaning 'good color and quite free from 

flaws, are very rare, and have nearly as much value as the 

ruby. 

An emerald of twenty-four grains, and good color, was 

sold at the auction of the Marquis de .Dree, for two thou- 

sand four hundred francs. Emeralds of indifferent pale 

color, are sold for two 'dollars per carat. The faults to 

which emeralds are subject, are inequality of color and 

transparency, dark or white spots, fissur.es, and feathers. 

. For emeralds, there are sometimes substituted the green 

tourmaline. and apatite; the former is easily detected by 

its property of becoming electric by heating ; but in general 

all these stones do not 'possess the lustre and hardness 

of the emerald. The pastes in imitation of the emerald, 

are so well manufactured that it is often difficult to dis- 

criminate the genuine from the false. The following yields 

the best imitation of the emerald : 

1000 parts of discolored strass, 

8 

" 

pure oxide of 02 

" 

copper, 

oxide of chrome. 

An emerald is said to have been at the Chapel of our 

Lady at Loretto, in Italy, larger than a man's head, and for 

which an Englishman offered ninety thousand crowns. 

The Sultan of Oude, in the East Indies, is said to have 

given to the King of England, among other presents, an 

emerald of the size of a hen's egg. 

" 

" 

" 

'"

EMERALD. 239 

The treasury of Vienna is said to contain an emerald of 

two thousand, two- hundred and five carats, valued at three 

hundred thousand crowns. 

The most magnificent specimen of emerald was presented 

to the cathedral of Loretto, by one of the Spanish kings. 

It consists of a mass of white quartz, thickly implanted 

with emeralds, more than an inch in diameter. 

An emerald belonging to the crown of Russia, is noticed 

in the Memoires du r&gne de Catherine, Tmperatrice de 

Ritssie, as being of the size of a hen's egg. . ' 

A fine crystal in the matrix, is in the museum at Dres- 

den, which I examined in 1827. 

Among the large emeralds stands foremost the magnificent 

crystal belonging to the Duke of Devonshire, as repre- 

sented on the frontispiece of this work; it is a regular 

six-sided prism, perfectly well formed ; two of the parallel 

faces are more developed tha*h the others, so that the 

hexagonal base of the crystal has one side larger than 

the rest ; the dimensions of the base are 2*36 inches, by 

1'97 in diameter, and it weighs eight ounces and eighteen 

pennyweights ; it is of a fine green color and perfectly 

clear in the upper part, it was found in a vein of dolomite, 

which traverses a hornblende rock at Muso, near Santa Fe 

de Bogota, in New Grenada. 

A prettier but smaller specimen, weighing but six ounces, 

is in the possession of Mr. Hope, of London. 

Mount Zalora, hi Upper Egypt, affords a less distinct 

variety, and was the only locality which was known to the 

ancients. 

At the New York Exhibition, in 1853, quite a number 

of emeralds were shown from the New Grenada mine. 

Dr. J. R. Chilton, of New York, has a very beautiful 

crystal of emerald in the matrix in his private cabinet, of 

one inch in length.


The largest cut emeralds and in great profusion, set in 

bridles, saddles, and in the girdle of an- apron, about the 

size of pigeons' eggs, were in the East India Company's 

collection. From forty to fifty of that size were set to- 

gether, some of them not well cut and polished, but all 

transparent and of beautiful tainly very 

green color, they were cer- 

valuable. 

Mr. Herz, of London, has a beautiful polished emerald 

of 112 carats.' 

Mr. Stephen H. Palmer, jeweller of this city, has some 

very fine cut emeralds, one of which weighs four and seven 

eighths carats, for which he asks $350. 

The prettiest cut emerald is in the imperial cabinet of 

St. Petersburg ; it weighs thirty carats ; is of pure color, 

and a perfect stone ; it has a round form with too many 

facets. 

The emerald has been* very successfully imitated, so 

much so that the most experienced eye may sometimes be 

deceived. 

BERYL, AQUAMARINE. 

This gem was likewise known to the ancients, who con- 

sidered and described it as a sea-green precious stone, and 

called the yellow varieties of this mineral the chrysoberyl. 

It was used' by the Romans as ornaments for cups, also for 

cameos. The crystals of the beryl are six-sided, terminated 

by six-sided pyramids, they also taper gradually from one 

end to the other ; the lateral faces are striated ; the frac- 

ture is conchoidal or uneven ; they are transparent or trans- 

lucent at the angles, with indistinct double refraction, and 

vitreous lustre : the colors are green, bluish-green, yellow- 

ish-green, or greenish-white ; bluish, sky, smalts, or indigo 

blue ; straw, wax, or honey yellow ; all pale colors : hard- 

ness,?^ ; specific gravity, 2'67 to 2:71. According 

to its

BERYL. 241 

color and transparency, it is designated the common and 

precious beryl : 

under the first are generally comprised the 

greenish and blue varieties, which are also called the aqua- 

' 

marine whereas the ; 

yellowish varieties are exclusively 

called the beryl, and are generally divided thus : 

1. Aquamarine, pure pale sky-blue. . 

, 

2. Siberian aquamarine, pale greenish-yellow, of a vivid 

lustre, faigt color. 

3. Aquamarine chrysolite, greenish-yellow, and yellowish- 

green, vivid lustre. 

The beryl belongs to the primitive formation, is found 

in quartz veins and granite (graphic granite), and is associ- 

ated with garnets, quartz, chrysoberyl, schorl, topaz, &c. 

The most magnificent beryls come from Siberia, Rio de 

Janeiro in Brazil, Aberdeenshire in Scotland, and Limoges 

in France. The common and translucent beryl occurs all 

over the globe, and in the United States in great abund- 

ance, where it is without mercantile value. The granite 

rocks of New Hampshire (at Acworth), have brought 

forth gigantic beryls, perfect six-sided crystals, three fee,t 

in length and four feet in circumference, and weighing up- 

wards of three hundred pounds, and some with a distinct 

termination of the crystals. Specimens of this description 

may be seen in the collection of the Lyceum of Natural 

History, New York, in Mr. Gilmore's collection at Baltimore, 

and in the author's collection. Large quantities of 

beryl crystals have also been found in Chester county, 

Pennsylvania. 

The beryl is cut on a leaden plate with emery, and 

polished with rotten-stone on a tin plate, and generally of 

the brilliant cut, on account of Its not possessing much 

lustre in the interior. 

The foil that is required in mounting, depends upon the 

color of the stone : the greenish variety, for instance, is set 

11

' 

24:2 A POPULAR TREATISE ON GEMS. 

with a greenish-blue foil ; the pale is set in a black ground, 

like the diamond, or on a silvery foil. 

Beryl is- employed in jewelry for rings, pins, ear-drops, 

seals, &c. : but 011 account of its softness it is rendered 

less lasting, and as by wearing it loses all its beauty, it 

does not command a high price in market, being much 

below that of the emerald. 

A beryl of a carat, averages about one dollar and fifty 

cents, and the price increases in the same ratio with the 

number of carats. The beryl is subject to such faults as 

spots, feathers, and fissures. 

For the beryl, is sometimes substituted chrysolite, which 

is softer, however ; it is also imitated by paste, which ia 

likewise softer than beryl. 

One of the largest transparent beryls, weighing five 

hundred and ninety-five carats, was once in the possession 

of a mineralogist at Vienna. In 1811, a beryl of fifteen 

pounds, pure, was discovered in Brazil. In 1825, a beautiful 

rounded Brazilian beryl, of four pounds weight, was 

offered for sale for six hundred pounds sterling. 

Mawe describes a pure transparent beryl, altogether free 

of faults, seven inches long antf three quarters of an inch 

thick. 

In 1827, a superb aquamarine, weighing thirty-five gram- 

mes, was found in the borough of Mowzzinskaia, in Siberia, 

which the Russians are said to value at six hundred thousand 

francs. A very remarkable aquamarine, of extraordinary 

size, ornamented the tiara of Pope Julius I. 

There is also a very fine aquamarine in the Imperial 

Library of Paris, on which there is a well-executed engraving, 

by Erodus, of Julia, daughter of Titus. 

There is, according to Caire, another aquamarine in 

London-, weighing five hundred and forty carats. In the 

Mineralogical Museum, of Paris, there is an aquamarine

BEEYL. 243 

weighing one hundred and thirty-three grains; and another 

one in a rough state, and extremely beautiful, weighing 

over twenty carats, for which 15,000 francs were offered. 

There are many of the intaglios of the ancients in the 

aquamarine. 

Pliny speaks of the finest beryls as those "qui viridatem 

piiri maris imitantur," and hence the term aquamarine is 

applied to those beryls which have beautiful shades yf skyblue 

or mountain-green colors. 

The aquamarine was much employed by the ancients for 

engraving : there is one by Qnintillius, of Neptune mounted 

on marine horses ; another of a drunken Hercules, by Hyllus. 

A similar intaglio, with terrestrial instead of sâ horses,' 

is the treasure of Odescalchi. 

The specimen of beryl on the frontispiece was the prop- 

erty of Baron Struve, Russian ambassador at Hamburgh ; 

was of grass-green color, fifteen inches long and two inches 

in diameter. A similar, but smaller, specimen, and more 

yellowish-green in color, was in the case of Mr. J. Tennant, 

of London, at the Exhibition of 1851. Both are Siberian 

beryls. The most splendid specimen, weighing eighteen 

and a half pounds, which formerly belonged to Don Pedro, 

in size and form, resembles the head of a calf, and exhibits 

a crystalline structure on one side only ; the* rest is water- 

worn, perfectly transparent, and without a flaw, and of 

a fine gale bottle-green color. Beryls are frequently ob- 

tained in Brazil and Siberia of one foot in length, but they 

are commonly very deeply striated longitudinally. 

Mr. Francis Alger, of Boston, informed the author ot 

having obtained a huge beryl crystal nearly perfect, of one 

thousand pounds weight, from Acworth, in New Hampshire, 

about fifteen miles from Bellows' Falls. Beryls occur there 

in extensive veins of granite, traversing the gneiss. The 

localities of beryl are very numerous in the United States. 

it


In graphic granite, associated with black tourmaline, good 

clear crystals are found in Bocodoniham, and Taphain, 

Georgetown, Parker's Island, and at the mouth of Kene- 

bec river, in the State of Maine ; 

at Goshen and Chester- 

field, Mass., in irregular crystals of a pale-green color ; 

and 

transparent, at Monroe, in Conn., in a granite vein ; in 

Had dam, Conn., at the chrysoberyl locality, where the 

beryls of yellow and yellowish-green colors are imbedded 

with crystals of chrysoberyl and colunibite. 

' 

ZIRCON, HYACINTH, JARGON. 

Zircon*and hyacinth were regarded as distinct minerals 

until the improvement in chemical analysis proved the same 

constituents to exist in both, particularly zirconia, a peculiar 

earth: they are now considered. as two varieties of one and 

the same mineral. Zircon is also called jargon, and this 

name is either of Ceylonese or French origin. The ancients 

denominated hyacinth, the gem which is now known 

their true hyacinth was a dark 

by the name of carbuncle ; 

amethyst. The zircon was formerly used as a celebrated 

medicine. 

Zircon crystallizes in four-sided prisms, terminated by 

four-sided pyramids, with various modifications ;* the crys- 

tals are smooth, rough, or uneven; it occurs likewise in 

rounded pebbles; it is transparent and translucent; pos- 

sesses double refraction in a great degree ; 

and has a vivid 

vitreous lustre, approaching sometimes to adamantine. 

Color, from hyacinth-red to yellow and brown ; also, red, 

gray, white, brown, and greenish-gray. It slightly scratches 

* See in the frontispiece, a beautiful American zircon, from the cabinet 

of Dr. J. K. Chilton, of New York. It was found in Buncombe county, 

North Carolina.

ZIRCON. 

245 

quartz, but is attacked by the topaz ; its streak yields a 

white powder ; specific gravity is 4'00 to 4'70 ; hardness, 

7'5 ; 

it becomes electric by friction ; 

is infusible before the 

blowpipe, but loses its color at a low heat, the yellowish- 

brown, however* becomes redder ; acids do not act upon 

it. Its chemical constituents are zirconia an


color of hyacinth is preferable to that of zircon ; 

a carat of 

the former is worth from fifteen to twenty dollars. Zircon 

is imitated by pastes, which may easily be detected by their 

lustre, hardness, and specific gravity ; burnt topaz may be 

substituted for it. 

The jargon is a variety of zircon, being composed of the 

same constituents, and differing merely in color from the 

first. It is mostly of white, grayish-white, and greenish- 

white colors, with tinges of green, blue, red, and yellow ; 

but generally of a smoky white color. It usually occurs in 

worn angular pieces, or in small, detached crystals, of an 

octahedral form. The crystals are smooth, and of a bright 

adamantine lustre; have a conchoidal fracture, and double 

refraction ; seldom quite transparent ; is harder than quartz, 

and of a specific gravity of 4*3 ; loses its color when ex- 

posed to the blowpipe flame, but is infusible. It occurs 

chiefly in the sand of a river in Ceylon, accompanied by 

sapphire, spindle, tourmaline, &c. 

On account of its peculiar adamantine lustre, it has often 

been substituted for the diamond, and a century ago it was 

regarded as an inferior variety of the true diamond, and few 

of the precious stones were in more request, especially for 

mourning ornaments, for which the dark tone of its color, 

combined with its lustre, was supposed peculiarly appro- 

priate. It has no value, at present, in market, although 

it is still seen in the cabinet and in the collections of 

jewellers. 

Hyacinth differs from jargon and zircon only in color, 

being of a red orange color, very bright and transparent ; 

it is much more employed for. setting than zircon. It 

occurs also in the sand and alluvial deposits of some rivers 

in Ceylon ; at Espaillie, near Puy^ in France ; at Ohlapian, 

in Transylvania ; occasionally in volcanic tufa, in Auvergne, 

and at Vesuvius. Siberia affords crystals as large as -wal-

nuts. Splendid specimens 

GAENET. 247 

Occur also in Greenland and 

Hyacinth is not highly prized by the jeweller. A 

large hyacinth of two hundred and fifty carats, in the collection 

of Mr. Herz, of London, was offered at a nominal 

sum of fifty pounds. Wm. J. Lane, Esq., of New York, 

has a beautiful seal-stone of hyacinth, which the author has 

much admired. Mr. Herz has also a cut zircon of forty-six 

carats, which he values very highly. 

It is very doubtful whether the modern hyacinth is one 

of the number of stones called hyacinths, vdftivdo^ by the 

ancients. It is supposed that the name was applied to the 

amethyst pr sapphire. 

Garnet was well known to the ancients, who consid- 

ered the carbuncle as the same mineral, representing the 

whole species. It has been found among the ruins of Rome, 

in a variety of cut forms. But the name garnet is of 

modern origin, and probably was bestowed on this mineral 

from being found mostly in grams. 

The garnet crystallizes in dodecahedral forms, with many 

modifications; the crystals are sometimes flattened into 

and mas- 

tables; it -is also found in round angular grains, 

sive ; the structure is imperfectly lamellar ; fracture, more 

or less conchoidal, sometimes uneven and brittle ; lustre, 

shining vitreous; it is transparent and translucent; the 

color is blood, cherry, or brownish red, but almost invariably 

with a violet or blue tinge ; sometimes, however, we find 

garnet of a yellow, green, brown, or black color. 

The red garnet scratches quartz faintly, but is attacked 

by topaz, and even by the file ; 

its powder is reddish-green ; 

hardness, 6'5 to 7'5 ; specific gravity if from 3'1C to 4'30 ;


it becomes electric by friction ; 

heated by itself, the garnet 

grows darker, but resumes its color when cooled ; it fuses 

before the blowpipe into a black pebble. Its chemical 

constituents are silica, alumina, and the protoxides of iron 

and manganese. 

Garnet has names according to the different shadings of 

color : 

1st. Syrian garnet, which is also called the Oriental and 

precious garnet, almandine, carbuncle ; 

red, dark crimson color. 

this is of a blood- 

2d. Bohemian, or Ceylonese garnet, called the pyrope ; 

wine-red, nearly orange-yellow, deep colored. 

3d. Vermeille, or Aplome, having a deep shade of orange- 

yellow. 

Pliny describes vessels of the capacity of a pint, formed 

from carbuncles 

" non claros ac plerumque sordidos ac sem- 

per fulgoris horridi" devoid of lustre and beauty of color, 

which probably were large common garnets. The garnet 

is also' supposed to have .been the hyacinth of the ancients. 

a dark blood-red 

Pyrope is described #s presenting 

color by reflected light, but yellow .by transmitted light. 

Pyrope was so called from Ttvp, fire, onTopcu, to see, in allusion 

to its color. 

The almandine, or precious garnet, is transparent and 

brownish-red, while pyrope is blood-red. The" red garnet 

occurs imbedded in mica slate, granite, and gneiss, 

rarely in limestone, chlorite slate, serpentine, and lava, and 

is found in the greatest perfection in Ceylon, in the sand ot 

and in the alluvial soil of Pegu, Hindostan, Brazil, 

rivers ; 

and Greenland ; in Bohemia, in alluvium, near Collin ; in 

gneiss- at Zbislau; in Tyrol, in the Oetzthal, and on. the 

Greiner, in Carinthia, Styria; in Switzerland; at Ariolo, 

in Hungary, Sweden, Norway, Scotland, 

and in the United States, in North Carolina, Geor- 

Canaria, Maggia ; 

Spain ;

GAENET. 249 

gia, Massachusetts, and New Hampshire. Professor Edward 

Hitchcock once exhibited to the author some beautiful 

cut precious garnets from Berkshire county, Massachusetts ; 

the Hon. Mr. Clingman, U. S. Senator from North Caro- 

lina, has some very handsome transparent garnets from his 

district in Buncombe county, North Carolina. 

The common garnet is met with in dodecahedrons, from 

three to four inches in diameter, at Fahlun in Sweden, 

Arendal and Kongsberg in Norway, and the Zillerthal in 

Tyrol ; in Moravia, Silesia, and Siberia ; in granular limestone 

at Haslan, near Eger, hi Bohemia ; 

beautiful crystals 

of a rich brownish-red color, disseminated in hornblende 

gneiss, are found in Hanover, New Hampshire, in the 

United States; dark blood-red and splendid dodecahedrons, 

with peached and truncated edges, at Franconia, New 

Hampshire, in geodes, in massive quartz, calcareous spar, 

and magnetic iron ore ; at Carlisle, Massachusetts, beautiful 

geodes of crystals of transparent cinnamon color, accompa- 

at Monroe and Had- 

nying scapolite in white limestone ; 

dam, Connecticut, imbedded in mica slate, also associated 

with chrysoberyl, beryl, automolite, and columbite ; large 

dodecahedral crystals, two inches and more in diameter, of 

a dark brownish-red color, at New Fane and Marlborough, 

in chlorite slate ; also in mica slate, in Chesterfield, Massa- 

chusetts. 

Colophonite is a granular brown variety, and is found in 

Arendal, Norway, and forms a large vein in gneiss at 

Willsborough, New York, on Lake Champlain; a finer 

graded variety of yellow and red colors is found on 

Rogers' Rock, at Lake George. The colophonite is com- 

posed of coarse, roundish particles, oil-green and honeyyellow 

colors, and often possesses a fine iridescence. 

Alloehroite is similar to colophonite, but the particles 

are impalpable and strongly coherent.


Grossular has a pale gooseberry-green color (whence 

its name) ; 

in Kamtschatka. 

in serpentine, with idocrase, in the Wilni river, 

Topazolite is a honey-yellow garnet, 

in veins in ser- 

pentine ; has small yellow crystals ; found on the Mussa 

Alp, in Piedmont. 

Aplome presents the form of the dodecahedron, but 

the facets are striated, parallel to the shorter diagonal; 

its color is brown, sometimes greenish; from Sahla, in 

Sweden. 

Melanite, from peXag, black, occurs in black dodecahedrons, 

sometimes modified in volcanic rocks, on Monte 

Somma, in matter ejected by Vesuvius ; Frascati, Albano, 

near Rome, the Brisgau, in beds on the older rocks at 

Arendel, in Norway. 

Pyrenaite is found in minute, black, symmetrical dodec- 

ahedrons, and was . so called from its locality in the Pyre- 

nees, and at the Pic Eves Lids, near Bareges. 

Ouwarowite bears a close resemblance to the green 

garnet. It occurs in transparent emerald-green dodecahe- 

drons, with a hardness of V'05 harder than the garnet. It 

occurs at Bissersk, in Russia. 

The several varieties of garnet are quite different in their 

composition ; they all contain silicate of alumina, and va- 

riable proportions of the silicates of lime, iron, and manganese, 

which substances have the property of replacing one 

another without causing a change of crystalline form. The 

f varieties of garnet are often classed as distinct species, such 

as almandine, pyrope, dodecahedral garnet, melanite, grossular^ 

topazolite, aplome, essonite, cinnamon-stone, Green- 

Jandite, pyrenaite, colophonite, allochroite, Romanzovite, 

carbuncle, and ouwarowite. It is proper that garnet be 

divided into precious and common; the first being the 

transparent, and the latter the opaque variety. The pre-

GARNET. 251 

cious garnet, is again divided, according to its transparency, 

into almandine and pyrope. As already stated, the dif- 

ferent varieties differ very little, and as the only important 

species, possessing characters more distinctive than 

others from the garnet, is the cinnamon-stone, or essonite, 

the author has seen fit to separate it from the garnet, and 

to describe it under its proper head ; moreover, essonite 

is more used by jewellers, when cut, than any of the other 

species of garnet, 

and as it has of late become fashion- 

able, it may be well to give a fuller description 

same. 

of the 

Garnet was the carbunculus of the ancients. This term 

was probably applied also to the spinelle and Oriental ruby. 

The alabandic carbuncles of Pliny were so called, because 

hence the name 

they were cut and polished at Alabanda ; 

almandine, now in use. 

In Bohemia, where there is a considerable trade in gar- 

nets, they are separated from the earth by levigation, 

then assorted into different sizes, afterwards washed again, 

and assorted as to color and quality, and according to the 

quantity required for balancing a certain weight, as half 

an ounce, they are called 32, 40, 76, 100; very seldom 

do they find them 16 to 20, weighing together half an 

ounce. 

The larger garnets are cut on the leaden wheel with em- 

ery, or their own powder, and polished with rotten-stone 

or oil of vitriol, on a tin plate, in the form of brilliants, 

roses, table-stones, or in cabochon, or with two rows of 

facets at the girdle; and very often garnets are brighter 

and more agreeable by excavating them circularly on the 

bottom ; they are then called garnet-cups. I have in my 

possession several large excavated garnets, and I saw at 

Berlin, in 1828, such garnets of two and three inches size. 

Fine garnets are set d jour others are set with a gold


or violet foil at the base. Smaller garnets are wrought on 

a large scale in manufactories for that purpose. They are 

perforated with the diamond, first, by 

point, then of a larger, and at last a finer point ; 

means of a small 

one hun- 

dred and fifty garnets may be perforated daily. 

The best garnets are cut in brilliant iorm, and with regular 

facets, on a plate of fine sandstone, with sweet oil and 

emery. One man can finish thirty such garnets. in one day. 

The polishing on wooden or leaden plates, with rotten-stone 

or oil of vitriol, is performed by women and children. 

More than twenty thousand garnets are yearly carried to 

market from a single manufactory. 

Garnets are much worn in jewelry, *as -rings, breastpins, 

ear-rings, and necklaces; and sometimes snuff-boxes are 

cut out of the larger ones from Greenland, Syria, or Tyrol; 

the inferior pieces, unfit for cutting, are calcined and re- 

duced to powder, and employed as material for polishing 

other gems. 

The value of garnets is determined by their degree of 

perfection, as well as color, purity, and size. On account 

of their peculiarly deep color they must be cut very thin ; 

and all such garnets as retain their fine color, without being 

cut too thin, are held in high estimation, and stand in value 

near the sapphire. A Syrian garnet eight and a half lines 

long, and six and a half lines broad, and cut octangular, 

was sold at the auction of tne Marquis de Dree for three 

thousand five hundred 'and fifty francs. A fire-red oval 

Ceylon ese garnet, eleven lines long and seven broad, was 

sold for one thousand and three francs. They are generally 

sold by the pound, containing from sixty to four hundred, 

valued at about eight to ten dollars per pound ; but a set 

of one thousand of the best selected garnets, well cut, is 

sold at about sixty dollars. Garnet is harder than idocrase 

or oxide of tin, but the latter is heavier.

V 

253 

In the Mineralogical Museum of the Jardin des Plantes, 

in Paris, are some very fine garnets with engravings ; one 

^s a mask of Silene, crowned with vine leaves; another is 

also the bust 

Calphurnia's restlessness on the fate of Caesar ; 

of Adrian, from the cabinet of Odescalchi the ; dog Syrius ; 

a head of Augustus, belonging to the Prince of Orange. 

Garnet is very well imitated by pastes, which are, 

however, softer and lighter, and differ in many other 

respects. 

The following composition yields a superior imitation of 

the Syrian garnet : 

To 1000 parts strass, add 

500 

" 

glass of 4 

4 

" 

" 

antimony, 

cassius purple, 


ESSOXTTE, CIXXAMOX-STOXE. 

This gem was formerly considered identical with hyacinth, 

under which name it yet passes in commerce and 

among manufacturing jewellers, and in France it is called 

hyacinth de Ceylon; it is also called, in mineralogical 

works, cannel or cinnamon stone, which name it received 

from the Dutch gem-dealers, on account of its resemblance 

to the oil of cinnamon. Werner was the first who gave 

this stone the above name. 

*Essonite occurs in crystals and grains; its fracture is 

conchoidal and uneven ; it is transparent and translucent ; 

has simple refraction of light ; 

the lustre is between vitreous 

and resinous; its color is deep-red, hyacinth-red, or or- 

ange-yellow ; it scratches glass and quartz indifferently, 

but is attacked by topaz; its powder is white; specific 

gravity is 3'5 to 3*6 ; it becomes electric by rubbing ; acts 

sometimes on the magnetic needle ; fuses easily before the

254 A POPULAR ^REATTSE ON GEMS. 

blowpipe into a clear not affect it. 

greenish glass ; 

borax and acids do 

Essonite is found in the sand of rivers, and in the primi- t 

tive rocks of Ceylon, in considerable masses ; also in Scot- 

land. 

It is treated like garnet, by being cut on a copper 

plate with emery, and polished on a tin wheel with rottenstone. 

It also receives the form of other gems, and when 

set, it is mounted with a foil answering to its color. 

It is used for rings and breastpins. Essonite* is distin- 

guished from zircon by inferior hardness, smaller specific 

gravity, diminished lustre, and simple refraction of light. 

Garnet is heavier, and idocrase is lighter than essonite. 

TOURMALINE, RUBELLITE, SIBERITE. 

This mineral is as yet very little known among jewellers 

and the trade in general, although it has been in commerce 

for a number of years past, but under other names, such as 

red tourmaline, or siberite, brought from Siberia, and sold 

in the trade as Oriental ruby. 

Tourmaline was first introduced as a gem by the Dutch, 

who imported it from Ceylon. Tourmaline occurs in 

crystals and crystalline masses, and 

its forms are six, nine, and twelve 

sided prisms, with various trunca- 

tions and terminations, which com- 

monly differ in the number and size 

of the faces at the two ends. The 

crystals are long, striated, and com- 

plete, or aggregated into irregu- 

lar masses; the fracture is conchoidal and uneven, semi- 

transparent to opaque. It has double refraction of light, 

it has a 

which, however, is only visible in small pieces ;

TOTTRITALINE. 25 C 

vitreous lustre ; the colors are blue, red, green, and brown, 

of different shades. Several colors may often be observed 

in one and the same crystal, as, for instance, in the rubellite 

from Paris, in Maine, and Chesterfield, Massachusetts, in- 

closed by the green tourmaline ; 

and the color often varies 

in its different layers. 

Tourmaline scratches glass slightly, but is scratched by 

topaz ; its powder is white ; its specific gravity is 3*0 to 3'3 ; 

it becomes electric by rubbing, that end having the great- 

est number of faces being positive, the other negative. 

When tourmaline is heated it exhibits polarity, the iUbst 

modified extremity becoming positive and the other nega- 

tive. In this particular it resembles other hemihedrically 

modified crystals. At a certain temperature it loses its 

polarity, but exhibits it again on cooling ; its polarity continues 

with the decrease of temperature until it reaches 32 

Fahr. ; a continued increase of cold re-excites the electric 

polarity, though with reversed poles ; 

if the excited crystal 

be broken, ach part thus produced will equally possess 

polarity, and even in the powdered state it retains its pyroelectricity. 

Before the blowpipe it intumesces more or 

less, does not fuse, but vitrifies on the edges ; turns green, 

then yellow, then red, then milk-white, .then blue, and 

then black. Borax dissolves it pretty easily into a clear 

bead. 

The chemical composition of tourmalines varies greatly : 

they are composed of alumine, silica, oxide of iron, oxide 

of manganese, and boracic acid ; those from different localities 

contain either potash, soda, lithia, or calcia. The 

following are the different varieties, not -including, how- 

ever, the white, yellow, and black tourmaline, or schorl, they 

not being used as gems : 

1. Siberian tourmaline (siberite, rubellite, apyrite), which 

is of a carmine or hyacinth red, purple or rose red, passing


into violet ; sometimes, by looking through in one direc- 

tion, the red color changes into a blue color. 

2. Indicolite (Brazilian sapphire), of an indigo, lazulite, 

or Prussian blue color. 

3. Brazilian tourmaline (Brazilian emerald), of a grass- 

green or olive-green color. 

4. Ceylonian tourmaline (Ceylon chrysolite), of a green- 

ish-yellow color. 

5. Electric schorl, of a yellowish, reddish, liver, or black- 

ish brown color. 

^mrmaline occurs in rocks, such as granite in layers 

and gahgues, and in boulders ; it also occurs in the beds 

of rivers, and the localities are Siberia, St. Gothard, Ceylon, 

Brazil, Sweden, Saxony, 

and Moravia. In the United 

States, tourmalines are abundant, but there are very few 

localities of the betfer varieties, as those at Paris in Maine, 

and Chesterfield and Goshen in Massachusetts. 

The specimen of a crystal of rubellite, from Paris, Me., 

on the frontispiece, is a perfect prism, is dark^ red on the 

inside and dark green on the outside, and belongs to Prof. 

Charles U. Shepard, of. New Haven, who exhibited it in 

thje New York Exhibition in 1853. There are several 

beautiful green and red transparent tourmaline crystals, 

from the same locality, in the mineralogical museum of 

Yale College, from the collection of the late Baron Lederer, 

Austrian consul in this city. 

The yellow tourmaline, from Ceylon, is but little inferior 

to the real topaz, and is often sold for that gem. The green 

tourmaline, when transparent, is often highly prized. 

The Siberian red tourmaline, called .siberite, is cut in 

cabochon, and exhibits then a milk-white chatoyant lustre. 

The black tourmaline is called schorl. The localities of 

tourmaline are quite numerous : large size black tour- 

malines are found in Greenland at Hovelberg, in Bavaria 

'

TOURMALINE. 257 

near Bodenmays, at Karinbrida in Sweden, and near Bo- 

vey in Devonshire. Small brilliant crystals are met with, 

imbedded in decomposed felspar, at Andreasberg, in the 

Hartz mountains, forming the variety called aphrigite. Ru- 

bellite occurs in a species of lithomarge, near Ekaterinen- 

burg in Siberia ; pale yellowish-brown crystals 

are found in 

talc at Windiscji Kappell, in Carinthia ; white and varie- 

gated colored specimens come from St. Gothard and Sibe- 

ria, the first imbedded in dolomite. 

In the United States, some magnificent specimens of red 

and green tourmalines were found in 1829 at Paris, State 

of Maine ; 

some transparent crystals from that locality ex- 

ceed two inches in diameter, and very frequently one inch, 

and present a clear red color internally, surrounded by 

green, or are red at one extremity and green at the other. 

Blue and pink varieties, most commonly imbedded in lep- 

idolite, are yet occasionally found in this locality. 

Red and green tourmalines occur also at Chesterfield, 

Mass., in a narrow vein of granite traversing gneiss ; the 

crystals are commonly small and curved, nearly opaque, 

and exceedingly frangible. Green crystals often contain 

distinct prisms of a. red color, especially when they occur in 

smoky quartz ; 

blue tourmalines also occur at this locality, 

and are accompanied by albite. 

The Russian Mineralogical Museum was supplied, in 

1832, by its minister, Baron Crudner, with specimens of 

fifty pounds weight, containing the rock of green 

and red 

tourmalines, from the Chesterfield locality. 

At Goshen, Mass., similar varieties occur, and the blue 

tourmaline is met with in greater perfection ; very perfect 

crystals, of a dark-brown color, occur imbedded in mica 

slate, at Monroe, Conn. ; the crystals are commonly from 

one to two inches long, and nearly as broad, and uniformly 

they are perfectly terminated at the two extremities.


Haddam, Conn., also affords fine black crystals, and some 

of large size ; they are profusely mingled in a mica slate, 

and associated with anthophylite and hornblende. A cinnamon-brown 

variety is met with at Gouverneur, N". Y., 

imbedded with quartz, and also associated with scapolite, 

apatite, and sphene, in granular limestone. These crystals 

are very often highly modified, and occasionally exhibit the 

faces of a scalene dodecahedron in addition to the terminal 

planes. Similar specimens occur at Grenville, Lower Can- 

ada, and Newton, N". J., associated with corundum, spinelle, 

and rutil ; and at Kingsbridge, N". Y., and Carlisle, Mass., 

with garnet. 

The red tourmaline, when transparent and free from 

cracks and fissures, admits of a high polish, and forms a 

most beautiful and costly gem. 

It has been supposed that tourmaline was known to the 

ancients under the name of lyncurium (Aw/covptov), which 

is described as having electrical properties; this name, 

however, was more probably applied to some variety of 

amber, which was so called from its supposed origin from 

the urine of the lynx. The identity of the red tourmaline 

with the hyacinth of the Greeks is more probable ; the 

other varieties were either unknown, or possibly connected 

under a common name with other species of the same color. 

Tourmaline received no attention from the moderns till 

Lemery, in 1717, published his discoveries. The word 

tourmaline is a corruption of the name for this mineral at 

Ceylon, whence it was first brought into Europe. 

The name schorl, which has been applied to the black 

tourmaline and some other mineral species, is reported to 

have been derived from Schorland, the name of a village in 

Saxony, which afforded specimens of this variety. 

Tourmaline is cut on a brass or leaden wheel with 

emery, and polished with rotten-stone on a tin plate ; it re-

QUABTZ. 

259 

ceivcs varfctis forms, such as the step and table cut. If of 

a pure color, it is set d jour, otherwise with a foil corre- 

sponding to its color ; 

but the electric schorl is sometimes 

set so that it can be removed from its mounting to be used 

in performing experiments. The value of tourmaline de- 

pends upon its color, purity, and size. The siberite and . 

rubellite stand highest in estimation. A siberite, as large 

as* five lines, is worth about one hundred and fifty dollars; 

and one of four to twelve lines, good color and pure, is 

worth about fifteefl hundred dollars. The rubellite from 

Paris, Maine, has become very rare, and it is muqh to be 

regretted that no more attention is paid to obtaining a 

freh supply, as the crystals are of an exceedingly fine 

purple color, and perfectly transparent. I have a few polished 

rubellites and green tourmalines in my cabinet, which 

I value equally as high as any gems. 

The dark-green tourmalines, six. lines long and four 

broad, are sold in Paris for eighty francs, and the light- 

green, of the same size, for forty francs. The most splendid 

siberite is at the British Museum, having been pre- 

it is valued 

sented by the King of Ava to Colonel Symes ; 

at one thousand pounds sterling. 

Tourmalines may be readily distinguished 

from other 

gems or pastes, which are sometimes substituted for them, 

by their property of assuming polaric electricity after being 

heated. . . 

QUAKTZ, 

This mineral is diffused all over the globe. Its varieties 

are very numerous, and many of them are employed in 

jewelry and for divers ornamental purposes. It occurs 

massive, in concretions, in confused crystalline masses, and 

in crystals, of which the form is the six-sided prism, termi- 

nated by six-sided pyramids; also the dodecahedron, or


double six-sided pyramid. Quartz scratches^rlass and 

felspar, but is attacked by topaz. Its hardness is 7*0. 

and its specific gravity, 2*5 to 2*7 ; it is transparent, and 

possesses a vitreous lustre ; becomes electric by rubbing ; 

is infusible before the blowpipe. Acids, except the- fluoric 

acid, do not act upon it. Silica is the only essential com- 

ponent part of quartz, but some varieties contain iron, alumine, 

or lime. 

ROCK CRYSTAL. 

This mineral was know r n in early ages. It was highly 

esteemed by the Greeks on account of its purity and very 

regular formation. Theophrastes 

states that it was "cut 

principally as seals, and the ancients made great use of it 

for ornaments, particularly before the art of making glass 

had reached much perfection. Among the many vessels 

which were cut in the form of cups, vases, &c., were two 

fine bowls and chalices in the possession of the tyrant ]&"ero, 

who purchased them at a large sum. Rock crystal was also 

used as a medicine. 

It is found crystallized, in the primitive form, which is 

the rhomboid, extended to a six-sided pi-ism ; and in a great 

variety of forms and modifications, such as with a truncation 

or replacement of the edges, or solid angles, &c. It 

is frequently found in groups, also in the cavities of other 

minerals, or in incrustations, as small, but very perfect 

crystals, the pyramidal terminations of which have a high 

polish, and the specimen* appearing as if it were studded 

with gems. Many specimens of this description were 

brought from Vermont a few year's ago, and were eagerly 

purchased by the jewellers of this city for rings, earrings, 

and breastpins. Rock crystal has a conchoidal frac- 

ture ; is translucent and transparent ; possesses a double 

refraction of light; a perfect vitreous lustre; is limpid,

ROCK CRYSTAL. 261 

white, brown, bla*ck, or yellow; scratches glass; specific 

gravity, 2'65. The electricity acquired by rubbing lasts 

for thirty minutes. Before the blowpipe, when colored, it 

becomes limpid. The following varieties of it are made 

known by their names and characters : 

1. The pseudo diamond (Bohemian or occidental dia- 

mond), which is the limpid, colorless rock crystal, cut and 

polished. 

2. The iridescent quartz is that variety of rock crystal, 

the 'interior of which is replete with fissures and cracks, so 

that the refraction of the rays of light produce the rainbow 

colors. 

3. Citron (Bohemian topaz, occidental topaz, yellow 

quartz, Scotch pebble), which is of a pale, ochry, gold, 

whitish, lemon, or brownish yellow color. The false cairn- 

gouram of Brazil is a beautiful variety of yellSw quartz. 

4. Smoky topaz (cairngouram or true Scotch pebble, 

brown quartz, smoky quartz) is of a smoky or brown 

color. 

5. Morion is of a charcoal-black or brownish-black color. 

6. Hair or needle stone, or such rock crystal as has, in its 

interior, foreign substances, as rutil (red oxide of titanium), 

manganese, iron, chlorite, amianthus, or asbestos. When 

the stone is so cut as to represent the hair or needles in an 

upright position, they are called either Venus' hair (cheveux 

de Venus) , or Love's arrows (flbches cf amour). 

Rock crystal occurs in gangues, or rock cavities, in the 

oldest geological formations ; it is also occasionally found 

in some modern rocks. 

The mountain of Cairngouram, in Aberdeenshire, Scot- 

land, has furnished, and still continues to afford, many fine 

specimens of smoky quartz. The lapidaries of Edinburgh 

always meet with a ready sale of this far-famed stone 

among the* Scottish gentlemen, as the native produce of


their country. Many very beautiful sets of the Cairjigouram 

were exhibited in the London Exhibition. 

A group of rock crystal, in the museum of the univer- 

sity of Naples, weighs nearly half a ton. 

The black limestone of Quebec affords fine crystals of 

quartz. In the State of New York, quartz crystals, remarkably 

clear and perfect', from the size of a pin's head to four 

inches, are found in many localities. Diamond Island, in 

La*ke George, is a lamed spot ; Gouverneur, N. Y., affords 

splendid dodecahedral crystals, associated with an iridescent 

crystallized specular iron. At the Notch of the White 

Mountains, N. H., and at the locality of tourmaline at Paris, 

Maine, handsome crystals of brown and smoky quartz have 

been obtained. 

At Trentop Falls, in the State of New York, very perfect 

and completely terminated transparent crystals are 

found, with their endless modifications, some of them five 

inches long, and some containing drops of water. It is 

also found at Windham, Vermont, where the drusy variety 

occurs, which is extremely beautiful, and of variegated 

colors. About twenty years ago it had a great many ad- 

mirers, and was generally worn in brooches, rings, &c. 

It is also found in Maryland, Massachusetts, and on the 

Catskill mountains. 

V 

Rock crystal is obtained in Switzerland, and some other 

countries, by mining; those cavities geologically 

or me- 

chanically traced from the quartz veins, are sounded by 

miners in granite veins or other rocks, by means of in- 

struments, and when hollow, extensive preparations are 

made for procuring the whole produce of the cavities, 

which sometimes amounts to several tons. It is likewise 

procured from the sand of rivers, and it passes then under 

the name of flints ; also, from gangues or veins of. other min- 

erals. The smaller and clearer transparent ones are gener-

BOCK CRYSTAL. 263 

ally employed in jewelry and for ornaments ; but the larger 

specimens are first assorted and then split or cleaved, and 

the smaller pieces are sawed through with a copper wire, 

emery, and oil, into the desired sizes, when they are ready 

for being cut on copper or leaden discs, with emery and 

water, and polished on tin plates with rotten-stone, putty, 

bole, or other fine powder; or they may be polished on 

wooden wheels, lined with fur or leather. The forms which 

they generally receive from the lapidary, are the brilliant, 

rose, or table. The iridescent quartz, and the hair or 

needle stones, are only cut concave. Those specimens that 

"have a full pure wine-yellow color, are best cut in steps. 

When mounted, they are either d jour\ or with a black 

foil. Those which are spotted, or of an, irregularcolor, 

may be discolored by careful calcinati


country as white topaz, and command a fair price. Wellcut 

seal-stones are sold at from five to twenty dollars. 

Those of the brilliant-cut are sold at from fifty cents to a 

dollar a piece. 

The largest rock crystal is said to be in the 

collection of M. Rafaelli, artist, at Rome, and a large can- 

delabra of. iridescent quartz, is in the Vatican. The proprietors 

of the American Museum of this city, can boast of 

having one of the largest specimens of rock crystal from 

Brazil. It weighs two hundred and twelve pounds, is two 

feet and a half high, and one foot in diameter, and is a 

perfect six-sided prism. 

Two large crystals of quartz, attached by one of the- 

vertical faces, the crystals being each two and a half feet 

high by eight inches in diameter, w r ere exhibited by the 

Duke of Devonshine, at the London Exhibition, in 1851. 

The pyramidal summits of these crystals, which rise nearly 

a foot above the prism, are completely transparent, but the 

prisms are cloudy. These magnificent crystals were obtained 

from the Alps, having been discovered during the 

formation of the road over the Simplon, in a cutting made 

through the old rocks. I saw a most magnificent chandelier 

of rock crystal in the Tuileries, which is said to have cost one 

hundred thousand francs. The clearest rock crystal comes 

from the island of Madagascar, in blocks weighing from 

fifty to one hundred pounds. In Switzerland, and the province 

of Auvergne, in France, very fine specimens may be 

had. The Bristol, Buxton, Cornish, and Irish diamonds, 

which are all pyramidal crystals -of quartz, are known all 

over the world. 

A specimen of rock crystal in the Museum of Natural 

History, at Paris, measures three feet in diameter, weighs 

nearly eight hundred pounds, and was found at Fischbach, 

in France. 9 

Rock crystal may be easily distinguished from white

BOCK CRYSTAL. 265 

paste, called strass, as the latter is heavier, on account of 

.the metallic oxides contained in the composition. 

A very remarkable phenomenon in quartz is exhibited 

by the fluid drops -which are contained in many specimens. 

They occupy small cavities, and evince their presence, 

on turning the specimens, by the motion of the accom- 

panying air-bubble, like the bubble in a spirit-level. These 

cavities are sometimes of considerable size. Jacobson, of 

Copenhagen, possesses a geode of [quartz an inch and a 

quarter long, which contains at least half a cubic inch of 

fluid. Mr. Allen also describes a crystal of amethyst in his 

collection, which contains four cavities partially filled with 

this peculiar fluid. At a temperature of eighty-three de- 

grees the fluid dilates and entirely fills all the cavities, and 

as it re-appears on cooling, an ebullition is apparent. Sir 

David Brewster has ascertained that the. fluid is not, as 

was supposed, water, but of an oleaginous nature, from 

twenty to twenty-five times thinner than water. A considerable 

number of specimens containing the fluid were 

carefully examined, and he found that one part of the fluid 

is volatile at twenty-seven degrees, and the other was a 

fixed oil. Prof. Dana has lately named the "former, cryptoline, 

and the latter, brewsterline. There is a great difference 

in the specific gravity of both liquids. The more dense 

yields a transparent yellow resinous globule, which absorbs 

the 

humidity of the atmosphere, is insoluble in water and 

alcohol, but dissolves in hydrochloric, and nitric acids. 

Occasionally a bituminous fluid, resembling napththa, is 

contained in the cavities of quartz. 

A very peculiar gelatinous substance, appearing to be 

silica in solution, has been observed on breaking open 

geodes, and the production of a species of chalcedony from 

the subsequent evaporation, has also been observed. But 

the nature of the solvent of silica is not yet fully ascer- 

' 

12


tained. It is, however, held in solution in the hot waters 

of the Geysers of Iceland, whose solvent power is supposed - 

to be due to the presence of a small quantity of alkali 

and their high temperature. The Geysers have covered 

the part of Iceland in their vicinity with a silicious sinter 1 

. 

The pseudomorphous quartz, from North Carolina, con- 

tains fluids in large quantities in its cavities. 

Two pieces of quartz rubbed together in the dark, emit a 

phosphorescent light and a faint empyreumatic odor. 

AMETHYST. 

This gem has been known sinc$ the earliest ages of 

Greece and Rome ; the name is of Greek origin. The 

ancients believed that wine drank from tm amethyst cup 

of that 

would not intoxicate ; hence its name, expressive 

belief a/K0wn>s-, from a, not ; pcd, 

to intoxicate. As re- 

gards the color, Pliny says : "ad riciniam crystalli descendet 

albicante purpurae defectu," purple gradually fading into 

white. This is not, however, the only amethyst of the 

ancients ; the violet-colored sapphire, the violet fluor spar, 

(" sculptaris faciles," easily graven Pliny,) and some other 

purple' species were designated by the same name. It has 

also been supposed that 'garnet came under the same de- 

nomination. This name occurs in Scripture, being that of 

the ninth stone in order on the high priest's breast plate of 

judgment, with the name Issachar engraved thereon. 

Amethysts were always used for engraving. The bust of 

Trajan, in the Royal Library, at Paris, and the Apollo 

Belvidere, the Farnese Hercules, and the group of the Lao- 

coon, are splendid specimens of it. It occurs massive in 

boulders, or in hexahedral prismatic crystals, terminated 

by hexahedral pyramids. Its crystals are rarely as distinct 

as those of quartz, being, for the most part, latterly aggre-

AMETHYST. 267 

gated by the whole prism, the terminal pyramids alone 

its fracture is from con- 

being separated from each other ; 

choidal to splintry ; 

it is transparent to translucent; of a 

vitreous lustre ; color of a high and dark violet blue, and 

from its richest tinge to almost colorless, in one and the 

same specimen. It scratches white glass, gives fire with 

steel, but yields to the file. Its specific gravity, 2-75 ; becomes 

electric by rubbing, which lasts, however, but half 

an hour. Before the blowpipe it loses its color. Its com- 

ponent parts are pure quartz, colored by manganese and 

iron. It occurs in veins of the older formations, studding 

the interior of agate balls or geodes in tho amygdaloid and 

trap rocks of Hungary, Silesia, Saxony, Tyrol, Oberstein ; 

and as boulders of splendid specimens in Ceylon, Siberia, 

and Brazil. It is wrought in the same manner as rock 

crystal, being cut on a copper wheel with emery, and pol- 

lished on a tin plate with rotten stone. In order to raise 

its lustre, many facets, and very frequently those of a rose- 

diamond, are given to it in cutting. 

It is sometimes cut in" 

the form of a brilliant, and when set is supplied with a blue 

or red foil, provided the amethyst is pale, for the deep- 

colored ones do not require any artificial assistance. It is 

used in almost every description of jewelry, such as rings, 

ear-rings, and breastpins ; but it is set in necklaces to 

the best advantage, and is the only colored gem which 

may be worn with mourning, an advantage 

which adds 

'to its value. The amethyst is no longer held in such 

estimation as formerly, but the color, when intense and 

uniform, as also the size, contribute greatly to its value ; 

and good well-cut amethysts, of one carat, are worth from 

three to five dollars, and so on, in proportion to their size ; 

an amethyst fifteen lines long and eleven lines broad, ex- 

quisitely fine, was valued at five hundred dollars. 

The best amethysts now in commerce come from Cey-


Ion, Siberia, and Brazil; the first are commonly called 

Oriental amethysts, which, however, must be carefully 

distinguished from a much more valuable gem, the true 

Oriental amethyst, which is the violet 

.sapphire. I have 

in my collection a quantity of the Brazilian amethysts, 

which are of an intense violet color, and of a very large 

size. 

Amethysts occur also at Pic Bay, and at Gorgontwa, Lake 

Superior, crystallized in trap ; also at Bristol, Rhode Island, 

and occasionally throughout the trap region of Massachusetts 

and Connecticut. 

The amethyst, is valued by the jeweller in proportion 

to the dcpth r richness, and uniformity of its color, and 

its 

perfect transparency ;; it . forms, 

then, 

a stone of ex- 

quisite beauty, its color being, perhaps, more generally 

attractive than that of any other gem, especially as it may 

be obtained of as large a size as can be conveniently worn. 

It is worn by priests, bishops, and pontifical dignitaries- 

as a ring-stone set with brilliants. Like many other stones, 

it is less brilliant by candle-light, and it appears at all 

times to best advantage when surrounded with pearls and 

set in gold. 

Amethyst has lately been employed by the cameo-cutters 

of Paris, for cameos and intaglios ; the head is cut at the 

collet, which is the thick part of the stone, and the crown 

having diamond facets produces a fine effect. 

The is amethyst often imitated by fluor spar or violet- 

blue lime spar; both, however, are softer than amethyst ; 

the liine is lighter, and the fluor is heavier than amethyst. 

But it is imitated very strikingly by pastes, so that with 

great difficulty the real is to be distinguished 

from the 

imitation; the latter, however, is somewhat heavier, on account 

of the metallic oxides contained in the composition* 

The following is the best receipt for imitating the amethyst :

COMMON QUARTZ. 

1000 parts of strass, 

8 

" 

oxide of manganese, 

0'2 

" 

purple of cassius, and 

2G9 

.500 " oxide of cobalt, 

One of the largest geodes of amethyst was brought into 

England in 1819, weighing one hundred ami fifty pounds; 

it was two feet long and fourteen inches' broad, and con- 

tained most magnificent crystals, of the deepest violet color. 

On account of having been set down at too low a price at 

the custom-house, which was sixty-five pounds sterling, it 

was confiscated. 


But a few varieties of the common quartz are used in 

jewelry, which are : the Rose Quartz, the Oafs-eye, the 

Prase, and the Avanturine, 

Rose Quartz, 

This mineral generally occurs massive; it is semi-trans- 

parent, and translucent on the edges ; has a vitreous lustre ; 

conchoidal and splintry fracture ; is of a rose-red color ; some- 

times giving a lustre of mother-of-pearl. It scratches glass; 

has a specific gravity of 2*64 to 2*67; its color, which is 

derived from the oxide of manganese, becomes paler before 

the blowpipe. 

Rose quartz occurs in gangues of granite and gneiss, par- 

ticularly fine in Sweden, Bavaria, Bohemia, and Siberia ; 

also a beautiful dark color in New-Hampshire and Massa- 

chusetts. 

Rose quartz is cut and polished for jewelry ; such as 

rings, breastpins, and snuff-boxes; it is cut on a copper 

wheel with emery, and is polished with rotten, stone and 

putty, on a tin plate, receiving the form of a cabochon or


table, and when set requires a foil, colored by carmine or 

solution of gold, as it fades when exposed a long time to 

the light. The rose quartz is not held in great estimation ; 

the color as well as the lustre of faded rose quartz may 

be resuscitated by being left for some time in a moist 

place. 

A vase of rose quartz was in the possession of the Marquis 

de Dree, nine inches high and two inches in diameter. 

Cat's-eye. 

The name of this mineral is derived from the peculiar 

play of light perceptible on its surface, by which it resem- 

bles the rays of light in the eyes of a cat ; it is not ascer- 

tained whether the ancients knew this mineral, and whether 

it was comprised in their .asterias; but it is well known that 

cat's-eye is in high estimation among 

the Malabars and 

Moors ; and it is worn throughout the whole East, where it 

is employed as an amulet, being believed to possess the virtue 

of enriching the wearer. 

Cat's-eye occurs massive, and in more or less roundish 

pieces ; 

has a. conchoidal fracture ; 

is translucent and trans- 

parent sometimes on one end ; it has a shining lustre, 

between vitreous and resinous ; gray and brown, green, 

red and yellow color ; it presents a peculiar floating light, 

which is particularly visible if cut in high cabochon, as it 

usually is when brought to market; it scratches glass; has 

a specific gravity of 2'56 to 2'73, and contains 95 silex, 

1*75 alumina, 1'50 lime, and 0*26 oxide of iron. In many 

specimens, there may be observed small parallel white 

fibres, which are supposed to be the cause of its peculiar 

play of light ; but the semi-transparent varieties, which 

are equally chatoyant as the more opaque ones, present 

no such appearance. This leads to the conclusion that


27l 

amianthus in its finest fibres occasions the phenomenon, 

and the chemical analysis of the latter corresponds with 

the additional constituents of the cat's-eye. By exposure 

to a strong heat, it loses its lustre and transparency ; and, 

in' small fragments, is fusible before the blowpipe. Cat's- 

eye is found in fragments of gangues and boulders, of 

very small size, never larger than a hazel-nut, in Ceylon, 

on the coast of Malabar, in the Hartz mountains, Bavaria, 

and in this country, (in Vermont, New-York,


more probably he alluded to the emerald ; 

for the same min- 

eral is at the present time called the emerald mother or 

matrix by jewellers. 

it has a conchoidal fracture ; 

Prase occurs massive and crystallized; 

is translucent on the edges ; 

between vitreous and resinous in lustre ; and of a garlic- 

green color, the cause of which is, that actinolite is intermixed 

with the silex. It scratches glass ; has a specific gravity 

of 2-66 to 2-88, and is composed of silex, alumina, and 

oxides of iron and manganese. It is found in Saxony, Tyrol, 

Styria, Hartz, and the island of Elba. It is used for rings 

and pins ; also for snuff-boxes and other jewelry, and is cut 

in cabochon, and set with a gold foil at the base, by which 

its color is heightened, and rendered more agreeable. 

It is 

used in mosaic works, for foliage ; and likewise in the 

mounting of rubies, in order to raise their -color. Prase does 

not stand in great estimation ; 

for although it assumes a very 

good polish, it loses the same on long êxposure to the air, 

and grows spotty. 

Avanturine. 

This mineral received its name from bearing a resemblance 

to a glass paste, formerly manufactured in 

Italy. 

It is a 

brown or red quartz, which is massive and translucent, or 

opaque ; it has a resinous lustre, and its fracture is splintry 

and uneven ; it is penetrated with gold or brass-yellow glistening 

fissures, caused by the refraction of light, or by innumerable 

mica leaves. It scratches white glass ; has a specific 

gravity of 2 '64 to 2 '68 ; 

are its constituents. 

silex, with some alumina and water, 

The avanturine is. found in the Uralian mountains, Styria, 

&c. It is 

Cape de Gata, near Madrid, Nantes, Scotland, 

used "for ring-stones, ear-rings, and snuff-boxes. It is cut 

on a copper wheel, with emery, and polished with rotten-

JASPER. 273 

stone on a tin plate ; it is cut semi-lenticular or oval, does 

not take easily a good polish, but may be improved by 

rubbing the stone with oil of almonds* The value of avan- 

turine is much depreciated of late, and its imitation by glass 

paste, called goldstone, is by far superior to the real stone, 

which has nothing but hardness in its favor. This paste is 

manufactured in great quantities in France, by throwing the 

finest impalpable powdered brass into a quantity of colorless 

strass, or into a composition of 

105 parts quartz, 

85 " 

purified potash, 

230 " 

tin and lead alloy> 

50 " 

brass powder. 

The artificial avanturine, as made in Italy, is a silicious 

oxide of copper. The mode of 

manufacturing 

the best 

quality, which is done very extensively in Italy and France, 

is still kept a secret ; that the copper is reduced first to a 

sub-oxide, and nearly to its crystalline metallic state, may 

be inferred on examining with a microscope the common 

artificial stone, which has a most splendid appearance* 

The best ananturine is manufactured in Venice, by M. P. 

Bibaglia, who alone appears to have the secret of excelling 

the natural stone. Messrs. Fremy and Ckmendot, expert 

French chemists, have succeeded in approximating the Ve- 

netian manufacture, by heating 300 parts ground glass with 

40 parts of protoxide of copper and 80 parts of oxide of 

iron, and allowing the mass to cool very slow. 

Large blocks of the factitious avanturine, with a great 

variety of manufactured ornaments, were admired in the 

Paris Exhibition, in 1855. 

JASPER. 

This mineral is of Oriental origin, and is very often men- 

tioned in the Bible. * 

It was the sixth stone in the plate of 

12*


the high-priest. Jasper was well known to the Greeks and 

Romans, and according to Pliny, who has described sev- 

eral varieties, the best came from Scythia, Cypria, and 

Egypt, on the banks of the Nile. The lapidaries formerly 

made use of it in their works, particularly the Egyptian 

jasper, which afforded them abundant material. The column 

of Memnon and the foundation of the column of Pom- 

pey were constructed of it, and we find daily, among the 

excavations of Herculaneum and Pompeii, fragments of ruins, 

composed of Egyptian jasper. 

has a conchoidal frac- 

Jasper occurs in enormous masses ; 

ture ; is opaque ; its lustre is 

slightly resinous, like wax, 

often dull ; 

it is of white, red, yellow, green, blue, brown and 

black colors ; it scratches glass, but yields to rock crystal ; 

its specific gravity is 2-31 to 2*67. 

It is usually found in gangues, seldom in strata, in Egypt, 

Bohemia, Saxony, Tyrol, Hungary, France, Italy, Spain, 

Siberia, Corsica ; in the United States, principally in 

Florida, North Carolina, Massachusetts, &c. ; also, in Nova 

Scotia. 

A fine yellow jasper is found at Vourla, bayôf Smyrna, 

in a low ridge of limestone, to the right of the 

wateringplace, 

between the harbor and the high hills that commence 

their rise about a mile back ; it is here associated with a 

beautiful opal, coarse carnelians, chrysoprase, and hornstone, 

and these minerals seem to occupy in the limestone 

the place of the hornstone, which is found in various parts of 

the adjoining country, and also at Napoli di Romania, in 

Greece. The plains of Argos are strewed with pebbles of red 

Jasper. 

The jasper and quartz rocks of Siberia am well known 

materials of extreme hardness, worked only in the Russian 

empire, and are rarely met with, except as imperial presents 

to princes and distinguished foreigners. A group of

JASPER. 2*75 

very remarkable objects was exhibited among the Russian 

goods in the London Exhibition. The material of some of 

these vases is quartz rock, but most are of a kind of pseudo 

jasper or pseudo jasper lava, of greenish color, and extreme 

toughness and hardness, resisting almost every tool, and 

requiring to be cut with emery, like the hardest gems. 

These rocks chiefly exist in Siberia, beyond the Oural, and 

are in great abundance and variety. The vases of jasper 

were worked at the imperial manufactories of Ekaterinen- 

burg and Kolyvan. There almost the whole work is performed 

by manual labor ; the only machine used is a simple 

lathe, on which the object to be turned is placed, and 

worked by iron tools and emery. No tool will touch these 

stones, both chisels and files of the hardest temper turning 

without producing any effect. The time 'for furnishing 

vases of considerable magnitude is often many years, and 

their value is calculated by the cost of the large establish- 

ment kept at constant work. A large vase, measuring three 

feet on each side, in a square form, was exhibited, hollow 

under the rim, with foliage in the same, and was one of the 

great curiosities in the Exhibition. Smaller vases, an olive- 

green jasper urn, decorated' with admirably worked foliage 

in relief, from the imperial manufactories, were -likewise 

exhibited, all of which excited the admiration of the spectators; 

and since the times of the Greeks and Romans no such 

gigantic works, both in dimensions and weight, have been 

wrought. The quantity of intaglios and cameos from the" 

ancient Greeks and Romans is too numerous for giving them 

a space in this treatise, for it would fill a whole book to spe- 

cify the antiques which are scattered around the world, in 

the various museums of Rome, Vienna, Paris, London, Ber- 

lin, Dresden, and the private cabinets which have for centu- 

ries existed in noble families. 

According to their varieties, which are very numerous

276 A POPULAR TREATISE ON GfEMS. 

that is, in color and structure they receive their names \ 

but they may still be classified into the following two- 

divisions : 

1. Egyptian Jasper, (Egyptian pebble,) which occursin 

spheroidal pieces,, of a gray-brown and red color, the- 

form of which is cut and polished in annular represen- 

tations around its centre. It is found in Baden, tip- 

of the 

per Egypt, and other places ; among the pebbles 

river Nile it is 

frequently discovered ; and in the year 

1714, it was found near the village of Inch eric; by Paul 

Lucas. 

2. Ribbon or Striped Spar. It occurs in masses, with 

nearly conchoidal fracture, around which parallel, straight,. 

or twisted stripes of a gray, green, yellow, red, or brown 

color may be perceived ; it is principally found in Siberia, 

the East Indies, Corsica, Tyrol, and the Hartz mountains ; 

some of the West India islands produce most splendid spe- 

cimens. 

Jasper is principally used for seals, snuff-boxes, vases, 

table-plates, and for some architectural purposes. 

When in lumps, it is divided by means of copper saws 

and fine sand, and then cut on copper or leaden wheels 

with emtfry, and polished on tin plates with rotten stone, 

on wood 

colcothar, or charcoal ; or it may first be polished 

with pumice stone, and lastly on a tin plate with rotten stone 

and water. 

The yellow jasper is often employed in mosaic works in 

Italy, and the striped jasper as cameos. Jasper- has no 

great value in trad-e, unless it be of exquisite quality, and 

fine objects be made of it. It generally commands the 

best price in China, where the emperor has a. seal cut of 

it. A vase of red Jasper, with white veins, and one of 

black jasper, with yellow veins, may be seen in the Vatican. 

Chatouilles and other boxes of considerable size

CHALCEBONt, 

are frequently fotmd in the jewelry stores of France, Eng- 

land,- and the United States, 

HORNSTONE, 

Hornstone occurs massive, globular, stalactiform, and in 

pseudo-morphous crystals of carbonate of lime, and also in 

the form of petrified wood, (wood-stone or agatized wood.) 

Its fracture is either conchoidal or splintry ; it is opaque or 

transparent on the edges; has a dull or shining lustre;- deep 

gray, brown, red, yellow, or green, and rarely a pure color. 

Often it has several colors in one and the same specimen, 

such as points, spots, and stripes. It scratches glass, and 

has a specific gravity of 2 '53 to 2 '65. 

It is mostly found in the gangues of the older formation J 

also in the old red sandstones and alluvial formations, in 

Bohemia, Saxony, Sweden, Siberia, Hungary, and a number 

I 

of other places ; in the old red sandstone of Thuringia. 

have traced one stem of the red agatized wood eighteen feet 

in length and two feet in diameter. The price of hornstone 

is very low ; 

it is used for snuff-boxes, seals, crosses, mortars, 

and principally as knife and fork handles. It is now used 

by silversmiths to mount butter and dessert knives and forks," 

which are imported from Germany in considerable quan- 

tities-. 

CHALCEDONY. 

This mineral was held in great estimation by the ancients, 

who received their principal supplies from Egypt and other 

parts of Africa. In Rome, much use was made of it for 

cameos, many of which may yet be seen in collections. The 

inhabitants of Iceland are likewise said to value it very 

highly, and to attribute many medicinal properties to it*


It is found in crystals, such as cubes, but mostly massive, 

botryoidal, stalactiform, globular, or reniform, &c. The 

fracture is even, sometimes running into conchoidal or 

splintry ; 

it is semi-transparent 

or translucent, 

of little 

lustre, or dull ; of white, gray, blue, yellow, brown or green 

colors, which are all of a light shade, and variously figured, 

striped, spotted, &c. 

It scratches white glass, and has a specific gravity of 

2'58 to 2*66. It is distinguished into the following varieties, 

viz. : 

1. Chalcedony proper, or chalcedony x, wherein white and 

gray stripes alternate with each other. 

2. Mocha, or tree stones, are such chalcedonies as display 

black, brown, or red dendritical figures, 

3. Rainbow, or agate chalcedony, is chalcedony of thin 

and concentric structure, which, cut across and kept towards 

the light, displays an iridescence. 

4. Cloudy chalcedony, has a light gray and transparent 

base, with dark and cloudy spots. 

5. Plasma, dark grass-green. This mineral was very often 

employed by the ancients for cutting. 

6. Semi-carnelian, or ceregat, is generally called the yellow 

chalcedony. 

7. Sappharine, is the sky or sapphire blue chalcedony. 

8. St. Stephen's stones, is the white chalcedony, with 

blood-red spots. 

There are many more varieties, and in my own collection 

I have polished chalcedonies, among which, perhaps, 

as many 

again may be enumerated. 

Chalcedony was originally procured from Chalcedon, in 

Asia Minor, whence its name. 

Chalcedony is found in gangues, and in the cavities of 

Localities exist 

many rocks ; also in boulders and pebbles. 

in Saxony, Hungary, Faroe Islands, Ceylon', on the shores

279 

of the Nile, in Nubia, Nova Scotia, the UnUed States, (in 

Connecticut, Massachusetts, Pennsylvania, Ohio, New-Jersey,. 

Missouri, Florida,) and in other countries; but the best 

specimens are brought from Oberstein, Iceland, and the 

Faroe Islands. 

The finest specimens are employed in jewelry, for rings, 

pins, bracelets, necklaces, and seals; -the more common for 

snuff-boxes, vases, buttons, &c. The larger masses are cut 

by means of a copper wire, with emery and oil on a copper 

wheel ; they are polished on a tin plate with rotten stone, 

putty-powder, and pumice stone. The cutting is generally 

done on a large scale, like that of agate. Many are susceptible 

of receiving figures artificially, by means of the nitrate of 

silver. By Oriental chalcedony is generally understood the 

better qualities ; those chalcedonies of two or three divisions, 

called onyx, are used for cameos. 

The value of the chalcedony depends on its 

quality, such 

as purity, color, and the figures and drawings displayed on 

it ; and among all the varieties of chalcedony, the mocha 

stone stands the highest in price, and also the onyx, which 

is principally employed for cutting cameos, and according 

to its size, commands a high or low price. Mocha stones 

are sold in France at from five to eight francs. The cabi- 

net of Dresden contains a plate of onyx, about three inches 

broad and long, which is estimated at twenty-five thousand 

dollars. 

CARNELIAff. 

This stone was known to the ancients by the name of Sarda ; 

which, according to some, is derived from a place in Lybia 

or Sardinia, or, according to others, from the Arabic word 

sarda, meaning yellow; it has been employed very frequently 

for cutting intaglios or bas-relief gems. 

Carnelian occurs massive or in pebbles ; 

its fracture is con-

280 A POPULAR TREATISE ON 

choidal ; lustre resinous ; it is semi-transparent and translu- 

cent; of a blood-red, yellow-brown, or yellow color; fre* 

quently dark at the outside* growing paler 

side ; 

the colors are sometimes changing striated ;- 

towards the in- 

it scratches 

white glass, and has a specific gravity of 2-59 to 2 '63. There 

are two varieties known by lapidaries and jewellers which 

are better than the others; those having a pale color or yel- 

lowish tinge, and those having a dark-red color; the latter 

are in the highest estimation, and are called by the French 

cornalines de vieille roche. 

Sardonyx is called a carnelian, having as its principal color 

tne dark-brown or orange-yellow, interchanged with layers 

of a white color. 

Carnelian onyx has a blood-red base, marked with white 

stripes. The finest carnelians come from Siberia, India, 

Arabia, Nubia, Surinam, Oberstein in Germany, and Tyrol ; 

they occur mostly as pebbles or in .cavities of^ rocks. In the 

United States they are found on Lake Superior in large 

quantities, in Missouri, and in Massachusetts. The carne- 

lian is used for numerous articles in jewelry, such as seals, 

it is cut on a leaden plate with 

rings, watch-keys, &c. ; 

emery, and is polished on wood with pumice stone, 

and ob- 

tains its highest polish on a plate composed of lead and tin 

with rotten stone and water. The form of its cutting is 

that of pavilion or step cut, on the upper part, and either 

quadrangular, hexagonal, octangular, or round ; and for 

raising its lustre or color it is furnished with a, silver or 

gold foil, or with red paint on its base. The color of th 

carnelian is also improved by calcination ; the yellowish 

it in a moderate heat and 

kind, for instance, by calcining 

cooling.it slowly, may assume a good red color. It is said 

that the ancients boiled the carnelian in honey in order to 

heighten its- color. Colored figures or drawings may suc- 

cessfully be represented by a mixture of white-lead, colco-

CARNELIAN. 281 

thar, or other metallic oxides, and gum-water, which is the 

material for drawing on it, and by burning the same under a 

muffle. 

Carnelian is divided into Oriental and occidental ; the first 

is found in the old rocks, and is generally very hard, rich in 

color, clear and transparent, and takes a high polish, is 

brought from Surat, in the Indies, and valued at ten francs the 

kilogramme ; the occidental carnelian is softer, of a yellower 

red and less brilliant. 

Stygmite is a beautiful variety with variegated colors, of 

reddish-yellow or yellowish-red, with many white lines passing 

through the stones. 

The ancients, particularly the Romans, were very partial 

to engraving on carnelian, and some very remarkable stones 

are still in existence in the imperial library at Paris. The 

seal of Michael Angelo, which is valued at 50,000 francs, 

is said to have been engraved by Maria de Descias after 

the original of Praxiteles ; the bust of Ulysses, Hercules 

killing Diomede, Jupiter, Mars, and Mercury. 

The great scarabee in carnelian, in the Prussian cabinet, 

which represents the five heroes of Thebes, is a master-piece 

of Etruscan art. 

The crown jewels of France contain some very costly car- 

nelian engravings of very large size. 

The faults of the carnelian are fissures, unequal color, and 

flaws from other stones. Carnelian is, on account of its 

being less brittle, more useful for engraving and cutting 

cameos ; the white layers are generally used for the figures 

of cameos and' the red for the base. Sometimes such 

carnelians as are cut with bas-relief objects, are filled out 

with colored strass ; and we receive from India, very fre- 

quently, cameos with the most singular drawings, and which 

are made by the inhabitants in the following manner : the 

whole carnelian is covered with carbonate of soda, and then


exposed to the fire for a few minutes, whereby a strass is 

formed, upon which the figures 

are cut. The value of carnelian 

is much higher than chalcedony, but yet depends on 

all its qualities of color, transparency, equal division of color, 

and freedom from faults, such as fissures, clouds, dark spots, 

&c. For a perfect sardonix, a is very high price generally 

given, particularly when the layers are very distinct and 

run quite parallel, and are pretty thick, so that they are 

fit for cutting cameos or intaglios. The blood-red is second 

in value, and the pale-red third ; but the cheapest are the 

yellowish, brownish, or whitish kinds ; the prices vary from 

twenty dollars to twenty cents per piece. There exists a 

cameo of sardonyx, representing the portrait of the celebrated 

Father Fontanarosa, having his face white, with the base, 

show the 

cap, and cloak black, so that it may distinctly 

Dominican monk. 

HELIOTROPE, BLOODSTONE. 

This stone derives its name from the Greek language, 

having been used in ancient times for observing the sun. 

Pliny speaks of heliotrope. It occurs in massive and 

obtuse angular lumps, of a conchoidal fracture, is trans- 

lucent on the edges, of a resinous lustre, and leek-green 

It scratches white glass ; 

color, with red and yellow spots. 

has a specific gravity of 2*61 to 2'63. Heliotrope is 

found among amygdaloid, in Tyrol, in the United States, 

(in New-York, near Troy,) Scottish Islands, Siberia, Faroe 

Islands, Egypt, Barbary, Tartary, &c. It is principally 

employed in rings and seals, watch-keys, snuff-boxes, and 

other articles of jewelry, also for sword and dagger han- 

dles ; and is wrought like chalcedony, but sometimes cut 

on brass plates ; its forms are various : as cabochon and 

pavilion.

AGATE. 283 

Heliotrope has been greatly admired in modern times ; 

its pric'e depends upon the color and quantity of red spots 

contained in ft. From one to twenty dollars is the usual 

price for good and large specimens. 

It is said that superstitious people in the middle ages 

valued the 

heliotrope, with many red spots, very highly, 

thinking that Christ's blood was diffused through the stone. 

AGATE. 

This stone was well known to the ancients, under the 

name of achates, and was used for various purposes of jewelry. 

In Rome, it was principally used for cutting cameos 

from the striped kind, the onyx. It has also been worn as 

an amulet, with different characters engraved upon it. Its 

name is derived from a river in Sicily, where the ancients 

procured it. Agate is a mixture of several species of quartz, 

which are variously combined ; chalcedony or carnelian 

usually forms the principal part, and is mixed with hornstone, 

jasper, amethyst, quartz, heliotrope, cachelong, and 

flint; and according to the predominating substances, it is 

sometimes called chalcedony, jasper, 

or carnelian agate. 

Its 

color, as well as its other characters, depends upon the na- 

ture of the mixed parts ; likewise its hardness ; but it usually 

scratches white glass, and has a specific gravity of 2*58 to 

2-66 at the utmost. 

According to the different figures represented in agate, it 

receives its various names. 

1st. Ribbon, or striped agate, representing layers vari- 

ously colored, and alternating with one another. Onyx, 

or agate onyx, are such agates as have the colors beautiful 

and distinct, and whose layers run in a parallel direction 

with the larger surface ; whereas the common ribbon agates 

display their various layers on the surface, without being


parallel. If the stripes run together around the centre, it 

is called the circle agate, and if in the same stone the 

centre shows more colored spots, it is called the eye agate, 

or eyes tone. 

2d. Fortification agate is that brownish agate, the vari- 

ous colored stripes of which run in a zig-zag, or irregular 

lines and angles, representing the ground plan of fortifica- 

tions. 

3d. Rainbow agate ; the curved stripes have the property 

of displaying rainbow colors when held towards the sun, 

or candle-light, and the more distinctly if the stone is cut 

very thin. 

4th. The cloud, landscape, dendritic, figure, moss, punctated, 

star, petrifaction, shell, coral, tube, fragment, and ruin 

agates are all the various forms in -which the is agate dis- 

played, according to its figure or drawing. A ruin or fragment 

agate may be pasted together from the fragments of 

a common ribbon agate, so as to make it represent old 

walls, whereby it receives the name of breccia agate ; sometimes 

the rainbow agate occurs in connection with the shell 

agate, where the moss surrounding the petrified 

shells forms 

the rainbow agate. 

The royal collection at Dresden contains a table service of 

German agate; at Vienna, in the imperial cabinet, there .is 

an oval dish twenty-two inches in length, formed from a sin- 

gle stone. 

The achates of the Greeks were so called from the river 

Achates, in Sicily, whence, according .to Theophrastus, these 

stones were originally brought. 

J asp achates corresponds to our jasper agate ; sardachates 

contained layers of the sarda, or carnelian ; dendrachtes, 

from &evtpov, a tree, corresponding to our moss agate ; 

hsemachates, from dâ, blood, which was an agate sprinkled 

with spots of red jasper.

AGATE. 285 

Among the crown-jewels of France, is a very valuable set 

>f agates, ten cups and sa.ucers, four urns, four chandeliers, 

four busts, two ewers, two basins, two vases, two bowls, two 

salvers, one decanter, and one candlestick ; the whole set is 


At the French Exhibition in 1855, a magnificent Oriental 

agate, by Froraent Maurice, belonging to the Princess 

Mathilde, was exhibited, having the engravings 

of the 

three infatuations, 

the amorous, the poetical and sad, most 

tastefully represented. It is the Benvenuto Cellini of our 

day. 

The most celebrated cameo in Oriental agate, is the bust 

of Alexander the Great, which is a perfect gem ; 

the head is 

quite independent in color froin the base of the stone, and 

the execution without a blemish. 

The Orleans collection contained two agates : one repre- 

senting the death, of Cleopatra, as a half-body ; the other, 

Lysimachus, the head girdled with a diadem. 

A large black agate, particularly remarkable for its 

perfec- 

tion and .the complication of its workmanship, represented 

a captive followed by two generals on horseback, and 

several other persons, one showing a trophy, and another a 

laurel branch, 

An intaglio of Neptune, belonging to the Sabatini Museum, 

was also exhibited. 

Agate is found in gangues, in gneiss, porphyry, or amygdaloid 

; also, as boulders and pebbles, in rivers, &c. It 

is found in Baden, Oberstein, Saxony, Bohemia, Hungary, 

the Faroe Islands, Siberia, the West Indies, and in the 

United States, (Massachusetts, Rhode Island, New Jersey, 

Indiana, Missouri, Maryland, Georgia.) Those occurring- in 

amygdaloid are mostly in the form of geodes, or balls, 

hollow inside, and coated with quartz or amethyst ; when 

the rock begins to disintegrate, these balls, becoming


loose , fall scattering around the soil, and are then collected 

by persons who make a business of either selling or cutting* 

them. 

The agate is used not only for various purposes of 

jewelry and ornaments, such as seals, snuff-boxes, crosses, 

cases of various descriptions, ear-drops, &c., but also for 

numerous other useful purposes, on a large scale ; such as 

slabs, mortars, vases, instruments, knife and fork handles, 

playballs, &c. The manufacturing of th^m forms a considerable 

branch of 

industry in a 

part of Germany. The 

agate, after having been reduced to suitable sized pieces, 

by means of a saw, chisel or hammer, is then cut on a 

copper wheel by means of emery, powdered garnet or topaz, 

and is afterwards polished on a tin plate with rotten stone, 

putty or pumice stone. 

Oberstein, a small place in 'Rhenish Bavaria, in the north 

of Germany, has five large manufacturing establishments 

for the sole purpose of 

cutting and polishing the common 

gems or semi-precious stones, and it is the only place where 

this branch of business is carried to any great extent. 

Twenty mills are constantly driven by water, and more 

than one hundred thousand dollars worth of work is turned 

out yearly for export ; a sum which is small in comparison 

with the enormous quantity of goods manufactured and set 

afloat, but pretty considerable for such places, where labor 

is so cheap, and the best of workmen may be had for one 

dollar and fifty cents per week. At Oberstein the business 

is divided into two branches; the one is devoted to the 

cutting and polishing of the agate, 

and the other to the 

boring ; the workmen are called agate lapidaries and agate 

borers. The cutting is performed in the large agate 

mills, on sandstone ; each mill has generally five large 

sandstones, five feet in diameter and fourteen to fifteen 

inches in thickness, fastened upon a shaft, ^which causes

AGATE. 287 

them to revolve vertically, and which are 

continually 

moistened by a stream of water. The workman leans with 

his. body upon a peculiar bench, the seat of which is called 

the cuirass, and with his feet presses himself against a pole, 

whence he continually pushes the larger lumps of the agate 

towards the rnill-stotoe ; this, however, is often made so 

smooth from the friction, that it is often necessary to make 

it rough by knocking it with a sharp hammer, according to 

the kind of work, whether fine or coarse. The stones are 

either polished on sandstone or on wood, by means of fine 

clay or powdered chalk ; they are polished sometimes, also, 

on wooden wheels, covered with lead or tin. Snuff-boxes 

and other articles of agate, which are hollow, are polished 

on smaller sandstone wheels, which dimmish in size as the 

work advances. Agates which require to be bored belong 

to a particular branch, distinct from the other. The boring 

is performed by means of a diamond point, and is described 

by Mr. Mawe. The onyx varieties are mostly employed 

for cutting cameos, and are prepared there in such a manner 

that the darker layer is cut for the base, and the lighter for 

the intended objects. 

There is in Siberia, at Katherineburgh, an extensive 

manufactory for grinding and polishing agate 

and other 

gems. 

Many varieties of agate are used for engraving other 

stones, and also for the Florentine or stone mosaic work. 

Since agate has always been, and is 

yet, a favorite. stone, 

it has been attempted to improve either its color or other 

"external appearance by artificial or mechanical means ; this 

is done either by the use of metallic solutions or by boiling 

in oil of vitriol. The color has often been improved by 

giving to the stone, before it is polished, 

several strokes in 

succession, the small fissures thereby produced displaying 

an iridescence or some other phenomenon, if held towards


the light 5 this operation, liowev.er, may easily 

be detected 

by wetting the stone, when the water, entering the fissures, 

will destroy the effect; it will show itself again when dry. 

On some agates black and white layers are produced, in 

order to use or sell them in the place 

of real onyx this 

; 

who boil certain 

operation is performed by the lapidaries, 

varieties in oil of vitriol, which changes the color of some 

very soon to black, and renders others clear or still paler. 

Only polished agates are used for this purpose, and the cause 

appears to lie in the oil absorbed by them during the operation 

of polishing, on which account agates are by some first 

boiled in oil before submitting them to the operation of the 

oil of vitriol. 

The value of agate, although much reduced in com- 

parison to former days, a great deal depending upon the 

purity and perfection of color and peculiar figures, commands 

a pretty good price in the market ; it is particularly 

the onyx which is yet at high prices, and on that account it 

is imitated by pasting thin plates of chalcedony, jasper, agate, 

&c., together, and making them, by their different colors, 

appear like real onyx ; this deception may, however, be easily 

detected by it putting into hot water, which disengages the 

plates one from another ; the onyx is likewise imitated by 

pastes, and very happily, but may readily be distinguished 

from them by the hardness and other characters prominent 

in the real stones. 

Onyx, which, as already stated, is a .variety of agate, 

and most frequently 

of chalcedony, possesses 

in its intrinsic 

characters a- regular 

alternation of layers, which are 

more or less thick, and of distinct different colors, usually 

the grayish white, brown, and black predominating ; while 

sardonyx indicates one layer or more to be of carne- 

lian, and this is in higher estimation. It was this stone par- 

ticularly which the ancients mostly sought after for engrav-

AGATE. 289 

ing the heads of celebrated persons, their deities, and their 

idols; the fawn-colored variety, which is neither yellow 

nor red, was the highest in value. Both onyx and sar- 

donyx were purchased in Arabia and the Indies, and the 

harder the stones and finer the grain, the more valuable 

they were for the purpose of cutting. The title of Oriental 

of the 

onyx was always given to the finest qualities 

stones, regardless of the locality from whence they were 

brtmght. 

The Imperial Library at Paris possesses some of the most 

antique cameos and intaglios of onyx, 

such as Germani- 

cus, Marcus Aurelius, Faustina, and Tiberius ; the dread- 

ful Jupiter is an onyx in two layers ; Venus on a marine- 

bull, surrounded by cupids, are personifications 

of the 

highest perfection in the art. 

The superb fragment existing in Rome, and representing 

Antilochus announcing to Achilles the death of Patrocles, is 

another master-piece ; 

the cameo has a* black ground, with 

a white layer above, and the expression of grief on the 

three faces has secured to this cameo the decided suprem- 

acy of the ancient over the modern art. 

The bowl of Capo di Monte, in the Royal Museum of 

Naples, and the great cameo of Alexander and Olympia, 

belong to Mr. Bracciano, at Naples. 

The French Museum contained the great cameo of An- 

tonius and Faustina, engraved in different colors, but not 

parallel lines, it is not inferior to any other : the ground, 

which is of agate of brownish color, is Antonius, and 

above, in a white layer, is the pleasant figure 

of Faus- 

tina, whose drapery and hair ornaments are exceedingly 

well executed in a lilac color. 

The sardonyx is also called sarde, and if of a dark sable 

color, was preferred by the ancients for cutting intaglios. 

Mars and Venus when surprised by the gods, is executed 

13


by Valerio Yicentine; it represented nine figures. The 

Nuptials of Cupid and Psyche contains .five figures. 

In the inventory of curiosities belonging to the crown of 

France, made in 1*791, are mentioned two vases of sardonyx, 

valued at sixty-four thousand francs ; six sets, at one 

hundred and sixty-seven thousand francs ; 

two cups at six- 

teen hundred francs; one decanter at thirteen hundred 

francs ; one urn at six hundred francs ; but one remarkable 

sardonyx, of a grayish yellow mixed with brown, on which 

a Medusa head was engraved, was valued at twelve thou- 

sand francs. 

The onicolo or nicolo is another variety of onyx ; it is 

of brown ground with a band of bluish white ; 

it is distin- 

guished from onyx, by the lower layer being always thinner 

than the upper it is not so ; 

highly valued as either the 

onyx or sardonyx. The Mineralogical 

Cabinet at Paris 

possesses several cameos of this material ; one represents 

military piety ; also a cameo of Adonis, by Coinus. The 

stone is probably the cegyptilla, described by Pliny. 

The real sardonyx is the rarest mineral among that class 

of stones, on account of the multiplicity of layers, of which 

there are as many as ten, all, however, from the same sub- 

stances, but differently colored : such as chalcedony, jasper, 

agate, white, gray, red, and brown, opaque, translucent, 

bluish, or yellowish; they are highly prized, particularly 

those from the Orient. 

The finest cameo of the real Oriental sardonyx is in the 

imperial cabinet of Vienna, it is said to come from Diosco- 

rides ; it was obtained by Rudolph II., the German emperor, 

for 12,0(70 ducats. 

In the crown-jewels of France are some unique cameos 

of sardonyx, such as the triumph of Bacchus and Ariadne, 

valued at 7000 francs, and eleven other cut stones valued 

together at 60,000 francs.

AGATE. 291 

Great collections of antique onyxes, engraved as cameos 

and intaglios, are in Vienna and Berlin; in the first is to 

be seen the apotheosis of Augustus, which is ten lines broad 

and six high, and contains twenty perfect figures this was 

; 

purchased by the Emperor Rudolph at Frankfort-oir-the- 

Maine, for fifteen thousand ducats. 

The celebrated cameo in the Vatican Museum, at' Rome, 

is of agate, and represents Augustus. Italy has always been 

the great emporium for genuine antique onyxes and cameos, 

and occasionally we still behold fine specimens of art in the 

. 

possession of travellers coming from Europe. A very fine 

collection of antique cameos and intaglios in precious gems 

and antique pastes, likewise cameos and intaglios of modern 

artists, I have seen in this country, in the possession of 

Thomas G. Clemson, Esq., of Philadelphia. 

I have in my collection a good onyx of the Emperor Vi- 

tellius ; 

a splendid cameo of Bacchus, of two and one fourth 

inches long and one half inch thick ; 

Cleopatra ; 

one of Antony and 

also a splendid intaglio. 

In Paris are several celebrated cameos, worthy the notice 

of travellers going to Europe : the Brunswick Vase was cut 

from a single stone, and has the form of a cream pot, about 

Iseven inches high and two and a half broad on its outside, 

which is of a brown color; there are white and yellow 

groups of raised figures, representing Ceres and Triptolemus 

in search of Proserpine; Agrippina and- her two chil- 

dren, composed of two layers, brown and white ; 

the Quar- 

rel of Minerva with Neptune, which consists of three layers ; 

Venus on a sea-horse, surrounded with cupids, &c. 

The Museo Borbonico at Naples contains an onyx meas- 

uring eleven inches by nine the apotheosis of Ptolemy on 

one side, and the head of Medusa on the other ; both are 

splendid specimens of art, and supposed to be the largest in 

existence.


Two very beautiful flower-vases of black onyx, colored 

with natural white veins, two large cups of red chalcedony 

colored, long square links of chalcedony, connected together 

without joints, and alternating in colors, also a very beautiful 

snuff-box of green jasper, were seen at the London 

Exhibition, manufactured by Wild & Robinson, in Oberstein. 

Some modern works of cameo, from the hand of the cele- 

brated Puckler, are in the collection of Robert Gilmore, 

Esq., at Baltimore, and in that of W. J. Lane, Esq., of this 

city, who possesses also a Washington head of black and 

white onyx, by Isler, which is extremely beautiful; also a s 

very fine modern cameo in onyx, two inches in length, I 

saw in Stephen H. Palmer's establishment. 

CHRYSOPRASE. 

The ancients by this name designated a stone of a green 

but it is not certain whether 

color, with a yellowish tinge ; 

that which goes by this name, at the present day, is the 

same. We find, in the fourteenth century, this stone used 

as ornaments in churches and other places, but it was not 

known by the above name until 1740, when it was* discov- 

ered by a Prussian officer in Silesia. Frederick the Second 

ornamented his palace Sans Souci with this mineral. 

The common people of Silesia wear the chrysoprase 

around the neck as a charm against pains. 

Chrysoprase occurs massive and in plates ; 

the fracture 

is even and splintery; it is translucent; lustre, resinous; 

sometimes dull apple-green, grass-green, olive-green, and 

whitish-green color ; 

it scratches white glass distinctly, but 

is not so hard as true chalcedony; specific gravity, 2'56 ; 

it is infusible before the blowpipe, but loses its color when 

heated ; it consists of silex, with a little carbonate of lime, 

alumina, oxide of iron, and nickel ; its color is imparted by

CHRYSOPRASE. 293 

the latter substance. This mineral is found in the serpentine 

of Silesia ; also, in Siberia, and in the United States 

(in New Hampshire). 

Chrysoprase is used in jewelry and for various ornamental 

purposes, such as breastpins, rings, bracelets, necklaces, 

seals, &c. ; and the larger masses are used for snuff-boxes, 

cane-heads, table-plates, &c. The cutting is pretty difficult, 

and the greatest care is required for finishing the same 

with facets, as it is easily fissured ; 

it is done on tin or lead 

plates with* emery, keeping the first constantly 

wet with 

water ; it is polished on a tin plate with rotten-stone, but 

the lapidary has always to be cautious not to let it become 

hot, as it easily splirfters, and grows opaque and gray. 

The usual cut is the table or cabochon, with facets on the 

border ; in setting, a foil of green satin is often used for a 

back, but when pure and of good color, it is mounted djour. 

Inferior specimens are painted on the back with a mixture 

of verdigris, white lead, and gum mastic, or with sap-green. 

The chrysoprase loses its color by wearing; heat and 

sunlight likewise cause it to fade, and render it dark and 

cloudy ; but the color may be restored by keeping 

it in a 

wet or moist place, such as a cellar, in wet cotton or sponge, 

or even by dipping it in a solution of nitrate of nickel, 

which serves likewise to improve the inferior qualities. 

Very fine imitations in paste may be made by mixing 

1000 parts of strass with 

5 

" 

of oxide of iron, and 

8 

" 

of oxide of nickel. 

The chrysoprase is subject to a great many faults, such 

as fissures, either natural or received in cutting ; oily whitish 

spots, pale gray flaws and stripes, 

and sometimes small 

grains of clay of reddish color, intermixed in the interior of 

the stone ; but when pure, the chrysoprase has always been


a great favorite. A good seal or ring stone may be worth 

from twenty-five to thirty dollars, and smaller specimens 

from one to five dollars. The apple-green variety is most 

valued, and a specimen one line long by one half broad, 

has been sold at from fifty to one hundred and fifty dollars. 

At Paris, an oval chrysoprase, eight lines long and seven lines, 

broad, was- sold for three hundred and ten francs. The 

price generally has decreased of late, on account of the 

great quantity cut from the mines, which have recently 

been covered up, in order to raise its value again. At the 

royal palace of Potsdam, in Prussia, are two tables of chrys- 

oprase, the plates of which are three feet long, two feet 

broad, and two inches thick. 

CHRYSOLITE, PERIDOT, OLIVIN. 

The name of this stone is of Greek origin, and was well 

known to the ancients, although it is undecided whether 

they designated the same mineral by this name that we do 

at the present time, for they make it in their writings to be 

either the. topaz or goldstone, or the transparent gold- 

yellow stone. 

The chrysolite occurs in prismatic forms, generally a 

right prism with rectangular bases; also, in angular 

rounded crystalline grains or massive ; 

the fracture is conchoidal ; 

it is trans- 

parent and translucent; it possesses 

powerful double-refracting power ; its 

lustre is vitreous and resinous; the 

lateral planes of the crystals are some- 

times striated ; the color is olive-green, 

turning to yellowish and brownish; 

it scratches glass indistinctly, and is 

attacked by topaz ; hardness, 6'5 ; 

Fig. 10.

CHRYSOLITE. 295 

specific gravity, 3"33 to 3'44 ; becomes electric by rubbing ; 

is infusible by itself before the blowpipe, but is dissolved 

into a transparent pale-green bead with borax; 

acids do 

not affect it ; it consists of magnesia, silica, and oxfde of 

iron. Chrysolite is found particularly in basalt, trap, green- 

stone, porphyry, and lav% ; sometimes in alluvial deposits 

and the sands of rivers. 

The perfectly crystallized chrysolite is brought from 

Constantinople, but its true locality is unknown ; 

less dis- 

tinct crystallizations occur imbedded in Java at Vesuvius 

and the Isle of Bourbon ; imbedded in obsidian at Reel del 

Monte,. in Mexico; among sand at Expaillie, in Auvergne, 

in pale-green transparent crystals. 

Egypt, Natolia, and Brazil are the principal localities 

for the prismatic chrysolite; the oh*vin is more frequently 

found in imbedded crystals, and granular aggregations, in 

the basalts of the Habichtswald, the Eiffel, the Upper 

Palatinate, Geysingburg near Altenburg, Kapferistein. in 

and in the sienite at Elfaden in Sweden. The brown 

Styria, 

variety (hyalosiderite) is- found at Sabbach and Iringen on 

the Kaiserstahl, and hi dolorite, near Rpburg in Baden. 

Crystals of olivin, several inches in length, occur in green- 

stone, at Unkle near Bonn, on the Rhine, and it is a frequent 

ingredient of meteoric stones. 

The word chrysolite is derived from %pv0o$, gold, and 

/U0of, stone, in allusion to its color. 

The dark-colored peridots, which take a high polish, are 

now much worn in Europe ; they lose, however, their gloss 

very soon, on account of their softening. 

The ligurite is a species of chrysolite of an apple-green 

color, is transparent and of uneven fracture; hardness, 5 '3 ; 

specific gravity, 3*49. Its /4|kimary form is an oblique 

rhombic prism; the ligurite contains some alumina and 

lime in addition to the composition of the chrysolite ; 

it is

296 A POPULAH TREATISE ON GEMS. 

considered a superior gem to chrysolite, both in color and 

transparency. It occurs in a talcose rock on the banks of 

the Stura, in the Apennines of Liguria ; it does not become 

electrfc by heat or friction. 

The bot.tlestone of Moravia is likewise a species of chrys 

olite, of dirty-green and grayisto-green colors, does not 

occur crystallized, but in flat pieces of about an inch in size ; 

some specimens which the author collected in his youth, in 

Moravia, were fair specimens suitable for cutting, their 

color being dark-green. 

The chrysolite is cut on a leaden wheel with emery, and 

is polished on a tin plate with rotten-stone or oil of vitriol. 

Sometime^ pale stones are finally polished with some olive 

oil, which, raises the color considerably : this last operation 

is applied to restore its lustre, after the chrysolite becomes 

dull 'by wearing. The form is that ojf a rose or table cut ; 

also in pavilion ; and when set, gold foil is used for its base : 

the -pale-colored chrysolite looks well with a green-colored 

dark chrysolites may be rendered clearer by a 

copper foil ; 

careful calcination. +'. 

The chrysolite^ used for rings and pins, but does not 

stand in high estimation, not possessing either a distin- 

guished color, strong lustre, or great hardness, and losing 

its polish by wearing ; on account of its softness, it wears 

off at the edges. Very good specimens of peridot from 

Brazil were brought into this country from France, and 

commanded a good price, a few years ago, viz : from ten 

to fifteen dollars a carat. 

Chrysolite was much esteemed by the ancients ; 

Queen 

Berenice received a chrysolite as a present from Phile- 

mon, lieutenant of King Ptolomeus. 

Cleopatra likewise gave one to Antony. Louis XIII. 

brought chrysolite into fashion at his court. 

Among the engravings in chrysolite is one of the Em-

IOLITE. 29Y 

peress Sabine, which is in the cabinet of Crispi, at Ferrara. 

Among the most extraordinary engravings in chrysolite, 

is one representing Ptolomeus-Oulet, king of Egypt, and 

the Nuptials of Cupid. 

IOLITE. 

This mineral has for a long time been brought from 

Spain, but has lately been made known and brought into 

notice by Cordier, afte'r whom it received the name cor- 

dierite / it is called likewise steinheilite^ and has several 

other names, which I will mention, in order that the reader 

may not be confused when the same mineral is presented 

as a gem, under different names; the most appropriate 

name is dichroite, from its property of displaying two 

colors when held in different directions ; it is also known 

aspeliom and prismatic quartz. 

It occurs in regular six and twelve sided prisms ; also, in 

crystalline grains, massive, and in pebbles ; its fracture is 

conchoidal and uneven ; it is transparent, 

exhibiting an indigo-blue color when held 

in the direction of its axis, or viewed by 

transmitted light, and appearing brown- 

ish-yellow when held at right angles ; it 

possesses some double-refracting power. 

Sometimes a ray of light, resembling that 

of the star-sapphire, may be perceived in 

iolite, particularly when cut; it has a 

vitreous lustre ; its colors are violet-blue 

and indigo-blue, sometimes with a tinge 

Fig. 11, 

of black and bluish-gray. It scratches glass, and is attacked 

by topaz ; its streak-powder is white ; hardness, 6'5 ; 

it 

it becomes 

ha's a specific gravity of 2*88. By rubbing, 

electric, and assumes polarity by heating ; it is difficult to


fuse on the edges, and becomes then a grayish-green 

enamel : borax fuses it into a diaphanous glass ; acids have 

no effect upon it ; it consists of magnesia, alumina, and 

silica, with some oxide of iron and water. 

It is often found under the names of lynx and water 

sapphire, the first of a pale 

and the latter of a darkish blue 

color. It is found in primitive rocks ; also, in blue day, 

in copper pyrites, in quartz or felspar, and in small de- 

tached masses ; the localities are at Baldenmays in Bavaria, 

occasionally in perfect crystallizations, but usually massive ; 

' 

it is associated with magnetic pyrites. The variety from 

this locality has been called peliom, from its peculiar smoky- 

blue color, from rrehiog. It occurs in quartz, at Ujordlero- 

soak, in Greenland ; in granite, at Cape de Gata, in Spain ; 

at Arehdal, in Norway ; at Orrijervi, in Finland ; at Tuna- 

berg, in Sweden, &c. Ceylon affords a transparent variety 

in small rolled masses of an intense blue color. At Had- 

dam, Connecticut, it is associated with garnet and anthoph- 

yllite in gneiss. It is occasionally employed as a gem, 

and when cut exhibits its dichroism, or different colors in 

different directions. The name iolite is derived from tov, 

a violet, and /U0o, stone, in allusion to its color. From its 

property of exhibiting different colors according to the 

direction in which it was viewed, it has also been named 

dichroite, from 61$, double, and %poa, color. 

The hydrous* iolite, from Sweden, of grayish-brown or 

dark olive-green . color, is a very soft mineral ; hardness, 

3'75 ; occurs in red granite, accompanied by a light bluish- 

gray iolite. 

If the stone is perfectly pure, it is used for rings and 

breastpins; is cut on a copper wheel with emery, and 

polished on a tin plate with rotten-stone, and receives the 

form of a cabochon, in order to let it display its proper 

colors, and in a cube form. Its price is not very high ; the

PRECIOUS OPAL. 299 

jewellers value it as an inferior quality of the sapphire, 

without paying any regard to its phenomena of light. 

Good-sized specimens are sold at about eight to ten dollars 

each ; at Paris, a good iolite, ten lines long and eight and 

a half broad, was sold for one hundred and sixty francs. 

When, a couple of years ago, the iolite was discovered by 

Professor Mather, at Haddam, Connecticut, it promised to 

be a valuable acquisition to American gems ; but the 

suppfy was very scant, and its original locality appears to 

be exhausted. Professor Torrey possesses a fine seal, in 

the form of a cube, from that locality, which displays its 

properties to the greatest perfection. 

A blue quartz is occasionally sold for iolite, but it may 

easily be distinguished by its colors and hardness. Sapphire 

is considerably harder than the iolite. 

OPAL. 

The precious variety of this mineral was known to the 

ancients, and received its name on account of the "play of 

colors which it has. The opal has a great many varieties, 

which are all considered more or less gems, and find their 

will therefore be treated 

application in jewelry ; they 

separately. But, as general characters, it may now be mentioned 

that opal scratches glass but slightly, while it is 

marked by rock-crystal ; it has a specific gravity of 2'OG.to 

2'11 ; it is infusible before the blowpipe, but decrepitates 

and falls into splinters ; it also dissolves with borax. Opal 

consists of silica with water, some oxide of iron, and some- 

times alumina. 

' 

PRECIOUS OPAL. 

This gem derives its name from the Greek word sig 

nifying the eye, for the ancients believed that this stone 

: *

300 A POPULAR TllEATISE ON GEMS. 

had the. power of strengthening the eye. It was highly 

esteemed by them, as we learn from l^liny, who thought 

that the play of color originates from the beautiful colors 

of the carbuncle, amethyst, and emerald. 

The phenomenon of the play of colors in the precious 

opal has not yet been satisfactorily explained. Hatiy attrib- 

utes it to the fissures of the interior being filled with films 

of air, agreeably with the law of Newton's colored rings, 

when two pieces of glass are pressed together. Mohs'con- 

tradicts this theory upon reasonable grounds, which are, that 

the phenomenon would present merely a kind; of irides- 

cence. Brewster concludes that it is owing to fissures and 

cracks in the interior of the mass, not accidental but of 

a uniform shape, and which reflect the tints of Kewton's 

scale ; but it is, in my opinion, sufficiently plausible, that 

the unequal division of smaller and larger cavities, which 

are filled with water, produces the prismatic colors, and for 

the simple reason that" the opal which grows, after a while, 

dull and opaque, may be restored to its former beauty if 

put 

for ti short time in water or oil. 

Although the precious opal was never found in the East, 

yet it bears the name of Oriental opal among jewellers: 

for in former times opals were carried by the Grecian and 

Turkish merchants from Hungary, their native locality, 

to the Indies, and brought back by the way of Holland 

to Europe, as Oriental opals. The precious opal is found, 

in small irregular gangues, nests of the trachytic por- 

phyry formation and its conglomerates, in Hungary, particularly 

in the neighborhood of the village of Czerwin- 

ccza ; also, in the Faroe Islands, Saxony, 

and South America. 

The Hungarian opal is found of various qualities, and is 

obtained from mines which have been wrought 

for several 

centuries ; and, according -to the archives of that part of 

the country, there were, in the year 1400, more than three


hundred workmen engaged at the mines near tlt above 

village ; whereas there are but thirty at present engaged 

there, 

mens. 

on account of the scarcity of large suitable speci 

The precious opal is principally used for rings, ear-rings, 

the smaller specimens for mount- 

necklaces, and diadems ; 

ing snuff-boxes, rings, chains, &c. It is ground on a leaden 

wheel with emery, and is polished with rotten-stone and 

water on a wooden wheel ; and, in order to increase its 

lustre, it is lastly rubbed with putty, by means of buckskin, 

or a woollen rag and red chalk. Its form is generally that 

of a semicircle, lens, or oval; sometimes of a table, and 

then also with some facets ; 

but great care has to be taken 

that the edges, on account of the softness of the stone, do 

not wear off. It is also apt to spring in a temperature sud- 

denly changing. When mounted, 

it receives a colored 

foil, or a variegated silk stuff, or a peacock-feather 

on the 

back, but it looks best in a black casing. 

Cracks and fissures may be removed by leaving the pre- 

cious opal for some time in oil. Very frequently the pre- 

cious opal is distributed in small particles in the matrix, 

called mother of opal, which is cut by the jewellers as 

boxes, and other ornaments 4 and very often, too, this 

matrix is plunged into oil, and exposed to a moderate heat, 

whereby the base grows b.lacker, and the true precious 

opal retains its ray of colors. In order to preserve the 

surface of the precious opal against wear and tear, it is 

covered with a thin plate of quartz crystal. The precious 

opal still stands in very high estimation, and is considered 

one of the most valuable gems. The size and the beauty 

those playing 

displayed by its colors determine its value ; 

in the red and green colors bear the highest price. Its 

value has latterly increased on account of the scarcity of 

the larger specimens. Formerly, a solitary large precious


opal, playing in the red color, was sold for two to three 

hundred ducats; and one playing in both red and green 

colors, about five lines long, was sold at Paris for two 

thousand four hundred francs; and lately a single opal, of 

fine colors, and the size of a dollar, was sold near the 

locality for three hundred thousand florins ; in this country 

precious opals are sold by the importers at the rate of 

four to ten dollars per carat, and single specimens, suitable 

for pins or rings, from two to twenty dollars. The mother 

of opal is, however, much cheaper ; one of five lines size is 

sold for three to five dollars. 

All experiments for imitating the precious opal have 

hitherto proved fruitless ; they were made either by preparing 

an enamel and adding several metallic oxides, or by 

affixing to the back of a clear or common opal or enamel, a 

polished thin plate of the mother of pearl, which may sometimes 

deceive the ignorant. 

The precious opal, when large and exhibiting its peculiar 

play of colors in perfection, is a gem of considerable value; 

it was used as an ornament among the Greeks and Romans, 

and was called opalus ; also paederos (Ttaidepd)?) , in allusion 

to its color and lustre as expressed in 

" 

Ipeprov repeva xpoa naidbs, having 

the : 

Orphic poem 

the delicate complexion 

of a lovely youth." The most magnificent Hungarian 

opal in the London Exhibition, called "the mountain 

of light" a very appropriate name weighed 526 carats, 

and was estimated at 4000 pounds sterling. 

From Honduras, at Gracias a Dios, large quantities of 

opals have been imported into this city for the last ten years, 

at first by the late Mr. De la Raye, and latterly by Mr. 

Aaron C. Burr ; 

and many large and beautifully cut speci- 

mens are in the possession of Mr. B. Palmer, of this city; 

they are by no means inferior to the Hungarian opal. A 

very large opal, cut and polished by himself, which he


values at four thousand dollars, is one and three quarters 

inches long by one and a quarter inches wide ; another, 

one and a quarter inches long by one inch wide, he prizes 

at. seven hundred and fifty dollars; and a third, one and 

one eighth inches long by one inch wide, he values at four 

hundred and fifty dollars. 

The ancients held the opal in great estimation, and the 

anecdote of the Roman senator, Nonius, is well known 

that he preferred exile to parting with a magnificent opal 

which Marc Antony coveted. 

In the French crown-jewels are two very large and 

beautiful opals. One is set in the centre of the Order of 

the Golden Fleece, and the other forms the clasp of the 

imperial cloak. They were purchased for 75,000 francs. 

The Empress Josephine possessed the unique oppl which 

was called " The Great Fire of Troy," on account of the 

great fire sparkles. 

The Vienna Cabinet possesses a very large opal, but 

unfortunately it is cracked. Count Walewski, who is a 

great amateur of gems, possesses a very beautiful opal, 

which is oval, the size of a franc-piece, and is said to be 

extraordinarily brilliant, 

The Imperial Mineralogical Cabinet at Vienna, contains 

the most celebrated specimens of precious opal ; one, par- 

ticularly, may 

be mentioned here: it is four and three 

quarter inches long, two and a half inches thick, and weighs 

seventeen ounces. It was discovered about' 1770, at the 

above locality, and transported to Vienna. It displays the 

most magnificent colors ; 

is perfectly pure, and not accom- 

panied by any. matrix. Half a million of florins were 

offered for it by a jeweller of Amsterdam, and refused on 

account of its uniqueness ; and the Viennese have not yet 

dared to put even any approximate value upon it.


FIRE OPAL. 

This mineral was first brought into notice by Baron 

Humboldt, who found it in Mexico. 

It occurs massive ; has a conchoidal fracture ; is trans- 

parent ; of strong vitreous lustre ; color, hyacinth-red, run- 

ning into honey, wine-yellow, showing carmine-red and 

sometimes containing dendritic draw- 

greenish reflections ; 

ings. Its specific gravity is 2 '02 ; loses one and a half per 

cent, by calcination, and leaves pale flesh-red fragments. It 

is found in the trachytic porphyry, in Mexico, and in the 

amygdaloid of the Faroe Islands. 

As the fire opal is very little known, it has not yet 

been employed in jewelry, but bids fair to find applications. 

It is ground on a leaden wheel with emery, and 

polished with rotten-stone on a wooden wheel. The forms 

of cabochon, table, or pavilion, might suit very well as ring- 

stones. 

The cabinet of the university of Bonn possesses a very 

large and fine fire opal, of the size of the fist. The largest 

specimen I have seen is in the royal mineral ogical cabinet 

at Berlin, which was deposited by Baron Humboldt on 

his return from South America, and which, if I recollect it 

well enough from the year 1827, must be at least six inches 

long and four inches thick. This is the largest specimen 

he ever found. A collection of six shades of fire opal, with 

six more varieties of the other opals, was presented to me 

in the year 1828, when in Berlin, by the Counsellor Berge- 

man, who received at that time a considerable quantity of 

polished specimens from the Faroe Islands, but all of small 

size. A splendid collection of fire opals was brought from 

Guatemala some years ago to this country. It is also called 

girasol, from its bright hyacinth-red tints.

HYDROPHANE. V , 305 

CO3CMOX OPAL. 

This mineral occurs massive and in rolled pieo^; also as 

stalactites; has a cOnchoidal fracture; 

is transient and 

semi-transparent ; has a strong vitreous and resinous lustre ; 

its colors are. milky, yellow, reddish, greenish-white, honey- 

yellow, wine-yellow, flesh, brick-red, and olive-green ; 

some- 

times dendritic (moss opal). Its specific gravity is 1 '9 to 2*1. 

The wax or pitch opal is subordinate to this variety. 

It is found in the same rocks as the precious opal, in Hun- 

gary ; in the hematite rocks of Saxony ; in the serpentine 

of Silesia; in cavities of trap and the amygdaloid rocks of 

Iceland ; 'Faroe Islands ; and in the United States (Penn- 

sylvania and Connecticut). 

It is used for rings, pins, and cane-heads ; but is, on the 

whole, not a favorite among jewellers,


It has, when dry, a white, yellowish, or reddish color, and 

a specific gravity of 1*95 to 2'01 and ; according to Hatly, 

a 

hydroplane, having been immersed for four minutes in 

water, gaiRd thirty-four centigrammes: 

The hydrophane is found in the porphyry of Hungary, 

France, Iceland, and the Faroe Islands. Large pieces of 

good and fine specimens of hydrophane are wrought and 

used in the same manner as the precious opal. 

It is said that the hydrophane becomes much quicker 

transparent in warm than in cold water ; the quickest in 

spirits of wine ; after which, it loses this property the 

sooner ; but when boiled in oil, it retains it, to a certain 

extent, for years. 

If the hydrophane is well dried and soaked in melted 

white wax, or spermaceti, it assumes the property, when 

warmed, of becoming translucent, and of displaying brown- 

ish-yellow or gray colors ; it is then called pyrophane. 

The hydrophane was formerly colored violet or red, by 

means of a decoction- of logwood and alum. 

The price of hydrophane is very high, on account.of its 

great scarcity, and because it is very seldom found in large 

lumps. 

"SEMI-OPAL. 

This variety of opal was formerly considered to be a 

pitch-stone, and if it assumes the fonn of petrified wood, it 

is called wood opal. It has a conchoidal and even fracture ; 

it is translucent and opaque; of a resinous and vitreous 

lustre ; 

its colors are yellowish, grayish, and brownish, the 

colors running mostly dnto one another ; sometimes the 

colors divide themselves ribbon-like. The wood opal is 

mdstly brownish, and displays, more or less, a ligneous 

aspect, with the form of branches. 

The semi-opal is found in gangues, in the trachytic

CACHELONG. 307 

porphyry in Hungary, in the serpentine in Silesia, in the* 

amygdaloid in Iceland and the Faroe Islands ; 

likewise in 

Moravia, Saxony, France, Greenland, and in the United 

States (Maryland and Pennsylvania). 

The semi-opal, on account of its taking a high polish, is 

used for many purposes in jewelry. There is an estab- 

lishment for manufacturing snuff-boxes from wood opal, in 

Vienna, and lately the varieties of wood opal, with layers of 

chalcedony, or semi-opal, have found a useful application for 

the cutting of cameos. The semi-opal is ground and polished 

like the precious opal, but with more difficulty, on account 

of its being more brittle. The form which it easily receives 

is in cabochon, but without facets. The price of the semi 

or wood opal is low. 

CACHELONG. 

According to Blumenbach, the name of this mineral is pf 

Mongolian derivation, meaning " a pretty stone ;" and ac- 

cording to Phillipps it receives its name from the river Cach, 

in Bucharia, on whose shores it occurs frequently in loose 

conglomerates. This mineral has been arranged under the 

head of chalcedony, but properly belongs to opal. 

It occurs massive, as a covering of other minerals, rarely 

reniform, often traversed with fissures in different directions. 

It has a conchoidal fracture ; is opaque, and of a pearly 

lustre ; milky-white, turning sometimes to a yellow or red 

color, and exhibits dendritic figures of manganese or green 

earth. ; It scratches white glass ; has a specific gravity of 

2'2 ; it decrepitates when first brought before the blow- 

pipe, but yet undergoes no change ; 

slowly, at a white heat. 

clissolves with borax, 

It is found in the same manner as chalcedony, some- 

times incrusting or penetrating it, in the amygdaloid of 

Iceland, Greenland, the Faroe Islands, the hematite of


Carinthia, the United States (Massachusetts), 

and Neva 

Scotia ; in Bucharia, in the sand of the river Cach, it is 

found loose. 

Caclielong being generally constituted of layers of different 

degrees of hardness, the sculptors of cameos profit 

thereby, for the purpose of producing better bas-reliefs. 

In the Imperial Library, at Paris, is a very fine cameo, 

representing Valentine III. 

Cachelong is much used in jewelry, for rings, seals, &c. 

The Calmucks of Bucharia manufacture of it tools and 

other domestic articles. It is cut on a copper wheel with 

emery, in cabochon, and receives the polish on lead plates 

by means of rotten-stone and putty. The price of the 

cachelong is pretty considerable, on account of its beauty 

and scarcity, as the specimens most frequently found in 

the above localities are seldom in layers of more than one 

quarter of a line, alternating with chalcedony. 

JASPER OPAL. 

This mineral stands between jasper and opal; and, al- 

though considered by Werner as belonging to the first, 

ought, nevertheless, more properly to be arranged with the 

opal, on account of its containing water in its. composition. 

The jasper opal occurs massive, in specks, stalactiform, and 

in geodic masses; it has a conch oidal fracture; is translu- 

cent on the edges, or opaque ; 

is of a strong resinous lustre; 

its colors are gray, yellow, red, and brown. Its specific 

gravity is 2'0 to 2*1. It consists of silica, water, and oxide 

of iron, amounting to forty-seven per cent. It is found in 

the trachytic breccias of Hungary; also, in Saxony -and 

Siberia. The best light and pure specimens are used for 

dagger and sword handles in Turkey. The price of jasper 

opal is low.

OBSIDIAN. 309 

OBSIDIAN. 

This mineral was familiarly known to the ancients, and 

its name is said to be derived from a Rpman, who first 

brought it to Rome from Ethiopia. Pliny states that the 

Romans manufactured mirrors and gems from it; the 

Mexicans and Peruvians manufactured their knives, razors, 

and sword-blades from obsidian, which appears to have 

served as a complete substitute for other materials with 

those nations, who were yet unacquainted with the use of 

iron for weapons and utensils of various kinds. Baron 

Humboldt says that Cortez mentioned, in his letter to the 

Emperor Charles V., having seen razors of obsidian at 

Tenochittan ; and the above naturalist likewise discovered, 

on the Sierra de las Nabajaz, in New Spain, the old shaft 

that was used for raising the rough obsidian, with relics 

of the tools and half-finished utensils. 

The inhabitants of Quito manufactured magnificent mir- 

rors from obsidian, and those. of the Azores and Ascension 

islands, and Guiana, used splinters of obsidian as points for 

their lances, razors, &c. 

Specimens of arrows and other articles, such as octangular 

wedges, were presented a few years ago to the New 

York Lyceum of Natural History, being relics from the 

ruins of Palenque. In the collection of Columbia College 

are some razors, or sacrificial knives, the gift of the Hon. 

J. R. Poinsett. 

Obsidian occurs massive, in roundish or obtuse lumps, 

balls, and grains ; has a conchoidal fracture ; is semi-trans- 

parent and translucent on the edges ; 

ous, and sometimes even metallic lustre; 

it has a strong vitre- 

its colors are 

either pure black, grayish, brownish, greenish-black, yellow, 

blue, or white, but seldom red; it sometimes displays a 

peculiar greenish-yellow shine, when it is called the irides-


cent obsidian ; there is rarely more than one color in the 

same specimen with stripes and specks. 

Obsidian scratches 

white glass indifferently, but is scratched by topaz; its. 

streak-powder is white ; it has 'a specific gravity 

of 2*34 to 

2'39. Obsidian is sometimes magnetic, so that small pieces 

show their magnetic poles. Before the blowpipe, the black 

and even at a white 

variety is fusible with much difficulty ; 

heat it does not melt into a solid glass ; but the gray and 

brown variety (marekanite) swells readily into a spongy 

mass. 

Obsidian consists of silex, alumina, with a little potassa, 

soda, and oxide of iron. 

The names, Iceland agate, lava, black-glass lava, volcanic 

lava, are all synonymous, and the mineral called bottlestone, 

in round grains of the size of a pea, is nothing but 

a green obsidian. 

Obsidian, sometimes, forms the cement of .whole mountain 

chains, often forms deposits in the trachyte and the 

streams at the foot of some volcano ; also, among the vol- 

canic ejections, and occurs in loose lumps in the sand of 

rivers, and at the foot of mountains. It is found in Iceland, 

Teneriffe, the Lipari Islands, Peru, Mexico, Sicily, Hungary, 

Asiatic Russia, the Ascension Islands, and on all the vol- 

canoes of former and present times. 

In the New York Lyceum of Natural History are several 

interesting specimens, presented by Don Correa, of Ta- 

basco, from the ruins of the city of Palenque ; 

such as con- 

cave or triangular wedges, and other masses of obsidian, 

from various localities. 

It is employed for several useful and ornamental pur- 

poses ; 

such as the making of ear-rings, necklaces, brooches, 

snuiF-boxes, knife handles, &c. -It is particularly worn as 

mourning jewelry; it requires, however, much care in 

working, being extremely brittle. It is ground 

on lead

AXINTTE. 311 

wheels with emery, and polished -with rotten-stone. It is 

kept in favor by the jewellers, on account of its high polish ; 

but its value is very indifferent, excepting that of the iri- 

descent obsMian, which commands a high price, and is 

sometimes seen cut in cabochon, and set in rings. 

There is no doubt but that obsidian is of volcanic origin^ 

being mostly found in the neighborhood of volcanoes, and 

that it is a glass, produced by volcanic fire, as it is a 

combination of silex and alkaline substances. The Neptunian 

theorists have endeavored to prove that it is occasion- 

ally found with the remains of decomposed granite, gneiss, 

and porphyry, with which it even alternates in layers. 

AXINTTE. 

The name of this mineral is derived from a Greek word, 

signifying an axe, and was applied to it oh account of the 

resemblance of its crystals to that implement ; it is also 

called by some English mineralogists, thumer-stone, from 

its first locality. 

- 

; : 

Axinite occurs in a variety of crystalline forms, which 

are reducible to the rhombic, viz : an oblique rhomb, or 

four-sided prism, so compressed that the edges appear 

sharp, like the edge of an axe ; likewise} massive and in 

specks ; its fracture is uneven ; it is translucent on the 

edges, or sometimes transparent; hag simple refraction 

of light ; its lustre is vitreous, also, resinous ; its colors arc 

violet-blue, brown, gray, and yellow; 

it scratches white 

glass, but is scratched by topaz ; has a white streak-powder ; 

its specific gravity is 3*27 ; it becomes electric by rubbing 

or heating; before the blowpipe it fuses into a grayishbrown 

glass ; acids have no effect upon it ; it consists of 

lime, alumina, and silex, with oxide of iron and manganese. 

It occurs in gangues and layers of various formations,

31T2 A POPULAR TREATISE ON GEMS. 

principally the primitive ; and is found in Dauphine, the 

Pyrenees, Gothard, Saxony (Thum), Norway, &c. 

This mineral takes a very high polish, particularly those 

specimens from Dauphine^ but has hitherto, on account of 

its scarcity, not found much application in jewelry, but will 

Hereafter be a great acquisition, as it may be used for rings, 

pins, and other small ornaments 

FELSPAR. 

The varieties of this mineral are mostly crystallized, and 

in very numerous forms ; but they are all distinguished by 

two great characters, which are, the foliated structure and 

peculiar lustre; the principal form is an oblique prism 

with unequal sides. Felspar scratches glass and is scratched 

by rock crystal ; its streak-powder is white ; it has a 

specific gravity of 2*5 to 2*6; before the blowpipe it fuses 

with difficulty ; on charcoal it becomes vitreous and white ; 

fuses with difficulty on the edges to a translucent white 

enamel ; acids have no effect upon it ; it consists of potash, 

alumina, and silex. 

ADULARIA. 

This mineral occurs in crystals (oblique prisms and rhom- 

boidal faces), crystalline fragments, and solid masses; its 

fracture is uneven; it is translucent on the edges; has 

double refraction of light ; the lustre is vitreous and pearly, 

more especially when cut and polished ; it throws out green- 

ish and bluish-white chatoyant reflections from the interior ; 

it cleaves in two directions ; the crystals often present the 

hemitrope form, which in polished specimens becomes obvious 

from the different directions of the laminae; its' colors 

are limpid-white, greenish, grayish, and bluish, frequently

ADULARIA. 313 

with a peculiar pearly shine, and sometimes it is iridescent. 

and softer than quartz. 

Specific gravity, 2 '5 ; 

In commerce, adularia goes under various names, such 

as ^noon-stone, sun-stone, girasol, fish-eye, and Ceylon or 

water opal. In the moon-stone the color is white, with 

small bluish or greenish shades, but the base is semi-trans- 

parent and milky ; whereas the sun-stone shows a yellow 

and reddish play of colors. Adularia is found in gangues 

and" cavities of granite, gneiss, and limestone, and in 

pebbles from Ceylon, Greenland, Bavaria, St. Gothard, 

Tyrol, Dauphine, and in the United States, particularly 

at Ticonderoga, near Lake Champlain, New York, Maryland, 

Pennsylvania, Connecticut, and Massachusetts. The 

adularia from St. Gothard is found in very large masses : I 

saw, in 1827, in the cabinet at Zurich, in Switzerland, 

groups of crystallized adularia, measuring two feet in 

length and one foot in thickness, the splendor of which 

dazzled my eyes. 

Adularia, displaying a good color, and strong pearly 

reflections, is now much used in jewelry, for rings, pins, 

and other smaller ornaments. Generally specimens which 

possess these qualities are cut out of large lumps, then 

ground on a lead wheel, in cabochon form, and polished 

with rotten-stone ; they are, hi general, mounted in a black 

case, whence it best shows its reflections. The moon-stone 

commands a good price ; exquisitely fine specimens, of the 

size of a bean, are worth from five to ten dollars, and some 

of them were sold at Paris, of six lines diameter, for seven 

hundred and five francs, and four lines for two hundred and 

three francs. 

The largest moon-stone, in a brooch, three fourths of an 

inch in length, I have seen, is in the possession of Francis 

Alger, Esq., of Boston ; and rough specimens, with most 

splendid reflections, I have admired in the collection of the 

14


late Dr. M. Gay, of the same city. Both these gentlemen 

are fortunate in possessing uniques in this country, which 

are of no ordinary scientific and commercial value. 

Among the varieties of felspar may be named ice-sf>ar, 

which is found in volcanic rocks, occurs crystallized in the 

Vesuvian lavas, and is of a white color. 

Murchisonite is a yellowish-gray variety of felspar, from 

Dawlish and Arran. 

Leclite^ or the hettefliata of the Swedes, has a peculiar 

waxy lustre and a deep flesh-red color, and is found at 

Gryphyttan, in Sweden, 

Conazeranite is a grayish-black or blackish-blue variety, 

from the steep defiles of Salleix, in the Pyrenees ; it occurs 

imbedded in limestone. 

Variolite is a dark-green variety of felspar, containing 

lighter globular particles ; originally found in Drac river, 

in France, but of late also in Piedmont, Switzerland, and 

Scotland ; in the Alps large blocks of several thousand 

pounds are found. This stone, when polished, takes a high 

gloss, equal to the most precious gems. Its name is derived 

from the peculiar spots flashing around the stone. 

The name adularia is derived from Adula, the ancient 

name of St. Gothard, where the prettiest specimens were 

first discovered. 

A very curious variety has been found in Siberia, of a 

yellowish color, but with innumerable gold spots disseminated 

throughout' the whole surface of the mineral; 

these reflections of light appear to be owing to very small 

fissures or cracks, or to a confusion of its lamellar system. 

The prettiest specimens, which are invariably cut in cabo- 

chon, look much like a reflection of a star, diverging from 

the centre ; they are very rare, however. This variety of 

moon-stone has often been confounded with the Oriental 

avanturine, but on examination may at once be detected.

COMMON FELSPJte. 315 

The Ceylon variety ought only to be called Oriental moon- 

stone, from the peculiarity that it is more uniform, not 

striated like that from St. Gothard, and having also a 

brighter lustre; its chatoyant qualities are therefore more 

prominent. 

Sun-stone contains minute scales of mica, and reflects a 

pinchbeck-brown tint. 

COMMON FELSPAE. 

This felspar occurs in crystals, massive, and disseminated ; 

its fracture is uneven and splintery ; is translucent ; has a 

pearly and vitreous lustre ; its colors are white, gray, red, 

yellow, and green, in their various shades, sometimes with 

a variegated bluish, greenish, or reddish play of colors ; its 

texture is compact, or minutely foliated. 

The amazon-stone, or green felspar, is from Siberia ; like- 

wise splendid grass-green felspar has been found in the United 

States, at Southbridge and Hingham, Massachusetts, and 

Cow Bay, New York; of apple-green color, at Topsham, 

and near Baltimore, Maryland. Also, the American glassy 

or vitreous felspar, found in Delaware, which ought prop- 

with this 

erly to be quoted as a distinct species, is arranged 

variety. 

Felspar is widely diffused all over the globe, 

and with a 

few exceptions is more common than any other mineral ; 

forms a constituent part of most primitive rocks, such as 

gneiss, granite, &c. ; is the principal ingredient of the 

sienites, porphyry, and, in fact, with a small percentage of 

other minerals, forms whole mountain ranges and chains in 

various parts of the globe : such we see in Siberia, the north 

and west of Scotland, &c., all of which are surrounded by 

felspar. Immense beds exist in the United States : around 

Wilmington, in the State of Delaware, is an inexhaustible 

deposit of exquisite and perfectly pure felspar; and ID 

it

316 A POPU1*E TREATISE ON GEMS. 

Connecticut and on the North River we see beds of the 

foliated felspar extending for miles. Sweden, Norway, and 

Greenland are likewise great depositories of the common 

felspar. 

The amazon-stone is used in jewelry for rings, pins, 

seals, snuff-boxes, &c. It is principally cut at Ekaterinen- 

burg, Siberia, where it is ground on a leaden wheel with 

emery, and polished with* rotten-stone on a wooden wheel; 

its form is that of cabochon, and sometimes that of the 

mixed pavilion-cut, when the table is to be cut pretty large, 

and arched, in order to display more distinctly its peculiar 

colors. 

Common felspar is of no great value, and . only 

the amazon-stone 

is used in jewelry, which commands a good 

price. Cut specimens, suitable for ear-rings or brooches, 

are worth from three to five dollars. 

A very fine specimen of the amazon-stone, in its rough 

state, may be seen in the New York Lyceum of Natural 

History. The imperial cabinet of St; Petersburg possesses 

two vases of this stone, which are nine inches high and five 

and one half inches in diameter. Although our vitreous 

felspar has not yet been brought into use for the purposes 

of jewelry and other ornaments, yet it bids fair to con- 

tribute, at one day, much to the national wealth of this 

country, for it is the best material for porcelain, china, and 

earthen-ware. Already have many cargoes of this beautiful 

mineral been shipped to France and England (six hundred 

tons of the Connecticut, Middletown, felspar were, accord- 

ing to Professor Shephard, last year shipped to Liverpool, 

and one hundred tons to the Jersey porcelain manufactory), 

where the manufacturer appears to appreciate better the 

purity of ingredients for the purposes just mentioned. Instead 

of 

receiving, as hitherto, the manufactured goods 

from abroad, made of our own raw material, it is earnestly

LABRADOR. 317 

to be hoped that w will shortly acquire skill, and exert 

sufficient industry to compete with loreign manufacturers 

in the art of making porcelain, with the superior material 

which nature has so abundantly lavished on this continent. 

I possess a splendid slab of the vitreous felspar, of one 

square foot, free from any admixture, and imposing in 

appearance. 

LABRADOR. 

This mineral was heretofore considered as a variety of 

felspar; but it has latterly been separated from it, and 

ought, therefore, no more to be called labrador felspar, the 

name by which it is known in all mineralogical works. 

Labrador was first discovered by the Moravian mission- 

aries on the island of St. Paul, on the coast of Labrador; 

and, according to others, by Bishop Launitz, in 1775, 

when it was first brought to Europe. Labrador occurs in 

crystalline masses, massive, and in boulders; it is of an 

uneven and conchoidal fracture ; its lustre is vitreous, and 

in one direction pearly; it is translucent; its colors are 

gray, with its various shades, such as blackish or whitish- 

gray, with spots of an opalescent or iridescent vivid play of 

colors, consisting of blue, red, green, brown, yellow, or 

orange, according to the direction in which light is falling 

upon the specimen ; sometimes several of these colors arje 

perceptible at the same instant, but more commonly they 

appear in succession as the mineral is turned towards the 

light. These colors are said to originate in fissures which 

intersect the texture of the mineral, as they are only perceptible 

from that side where they fall together with the 

foliated structure, and not like the opal, whose mass is sup- 

plied with fissures running in all directions. 

Labrador scratches white glass, is? scratched by rock- 

crystal, and is somewhat less hard than felspar ; its specific

318 A POPULAB TREATISE ON GEMS. 

gravity is 2'7l to 2'75 ; before the blowpipe 

difficulty, and is said to lose its play of colors ; 

it fuses with 

it consists 

of silex, alumina, lime, soda, with some oxide of iron and 

water. Labrador is found as a rock and boulder, in St. 

Petersburg, Norway, Bohemia, Saxony, Sweden, St. Paul's 

Island on the coast of Labrador, and in the United States, 

in Essex county (New Jersey), at the mouth of the North 

River, and near Lake Champlain, New York, where, 

according to the description given me by Archibald Mc- 

Intyre, Esq., its splendid colors are seen on both sides of 

the water, but a few yards apart, and the effect of the rays 

of the morning sun falling upon the rock and water at the 

same time, is said to equal that of the prismatic spectrum 

thrown into a dark room. 

Labrador is used for rings, pins, buttons, snuff-boxes, 

letter-holders, cane-heads, and other ornaments, such as 

vases and larger articles; but care has to be taken in 

grinding, that the direction where the *play 

of colors is 

visible is kept straight, and that it is cut in cabochon. 

The price of labrador is not very high, but soon after its 

discovery, a Doctor Anderson, having described the mineral 

as displaying all the variegated tints of color that are 

to be seen in the plumage of the peacock, pigeon, or most 

delicate humming-bird, and specimens having been carried 

to England, so great was the avidity to possess it, that 

small pieces were sold for twenty pounds sterling. The 

present price of good specimens is from two to ten dollars ; 

and a few years ago I purchased some letter-holders, which 

are beautiful specimens, for which I paid four dollars 

each. The largest specimens of labrador are in the col- 

lection of the Minerajogical Society, and in the museum of 

the Academy of Sciences at St. Petersburgh, which were 

found on the shore of the Pulkouka j 

one of them weighs 

(en thousand pounds. I have in my possession a rough

LABEADOE. 319 

specimen of the labrador of this State, merely rubbed off 

on the surface, and its colors, I venture to say, equal, if 

they do not indeed excel, in every respect, those of the 

specimens from St. Paul's Island ; and I anticipate the day 

when the citizens of New York will take as much pride in 

possessing labrador table and mantel slabs, as they now do 

in employing the Italian and Irish marble for these pur- 

to be inexhaustible in the 

poses ; for the resources appear 

rocky county of Essex. We do not see many specimens 

brought from the coast of Labrador, and I was informed 

by Mr. Audubon, on his return from that quarter, that he 

could not find any specimens. Mr. Henderson, of Jersey 

City, who presented me the above-mentioned rough specimen, 

had likewise splendid small polished specimens in 

breastpins, displaying all the properties in their full beauty. 

The same gentleman, who travelled last summer in com- 

pany with several scientific State geologists, mentions that 

they picked up beautiful specimens at the height of five 

thousand seven hundred feet above the level of the 

sea. 

In the collection of Columbia College is a fine specimen 

of labrador, brought from Gaspe, Lower Canada, by the 

Hon. Mrs. Percival. 

In 1799, it was announced" that in Russia* a labrador spar 

was discovered, where a perfect drawing and image of 

Louis XVI. could be distinctly traced, his head surrounded 

by a colored crown of pomegranate, with a rainbow border, 

and a silvery plume of azure color ; it was what may be 

called a lusus naturae. Count de Robassome, .formerly 

in the Russian service, was the possessor of this singular 

stone, and he demanded for the same, the sum of 250,000 

francs. 

There were some magnificent specimens, tables, and 

other ornaments, in the London Exhibition.

320 A POPULAR TREATISE ON GEMS.* 

In the New York Exhibition, were likewise fine speci 

mens exhibited from Labrador and the New York locality. 

HYPERSTHENE. 

This mineral was formerly annexed to hornblende, but 

has latterly been separated ; its name is derived from the 

Greek, and means of superior strength, in reference to 

the great hardness and specific gravity which it possesses. 

Hypersthene is found in crystalline masses it has an un- 

; 

even fracture ; 

it is opaque, and its colors are dark-brown, 

red, and greenish or grayish black ; the cleavage is parallel 

to the sides, and shorter diagonals of a rhombic prism ; its 

lustre is metallic, and when viewed in one certain direction, 

copper-red, light-brown, or gold-yellow, and in others it 

has a greenish play of colors. It scratches glass, has a 

darkish-green streak-powder, and has a specific gravity of 

3'38 ; it is easily fusible before the blowpipe on charcoal 

into a grayish-dark bead ; acids have no effect upon it ; it 

consists of magnesia, silex, alumina, and lime, with some 

water. 

It is found forming a constituent of the labrador rock, 

on the coast of Labrador, Greenland, and in the United 

States, on Brandywine creek in Pennsylvania, and in Essex 

county, New Jersey; fine specimens have been found in 

Hingham, Massachusetts. The French jewellers have lately 

begun to introduce this mineral for rings, pins, and other 

ornaments, on account of its high polish and beautiful 

color. The best-colored pieces are cut out of the mass, 

and ground on a lead wheel with emery in cabochon, and 

polished with rotten-stone. Beauty 

qualifications determine the price of this stone ; 

of color and other 

at Paris a 

hypersthene, in cabochon cut, eight to ten lines long and 

six lines broad, was sold for one hundred and twenty francs.

IDOCEASE. 321 

The mineral is, however, pretty rare, and has not yet 

been fully introduced. 

EDOCEASE. 

This mineral occurs mostly crystallized, in the form of a 

four-sided prism, terminated by four-sided pyramids ; also, 

massive ; its cleavage is parallel to all the planes of the 

prism ; it is transparent and opaque ; possesses strong 

double refraction of light ; its lustre is between vitreous 

and resinous ; its cross fracture conchoidal ; the crystals 

are all striated in length ; its colors are yellowish or 

brownish green, orange-yellow, sometimes blue and black. 

It scratches white glass and felspar, but is scratched by 

topaz. Its streak-powder is white, and it has a specific 

gravity of 3 '8 to 3*4. Before the blowpipe, it is fusible 

into a brownish glass. It consists of lime, alumina, silex, 

with some oxide of iron and manganese. 

Idocrase is found in different geological positions in 

primitive and volcanic rocks, in the cavities of the serpentine 

in the Alps, in Piedmont, Mount Soinma, Vesuvius, 

Etna ; also, Norway, Sweden, Spam ; in the United States, 

at Worcester, Massachusetts; Salisbury, Connecticut ; Cum- 

berland, Rhode Island. 

Idocrase, of pure green and brown colors, and transpar- 

ent, is used for rings and pins, and at Naples and Turin, 

it is principally cut for jewelry on a leaden wheel, and is 

polished on wood with pumice-stone. The forms it receives 

are the brilliant, table, and pavilion, and if perfectly pure, 

is mounted d jour ; otherwise with a suitable foil. The 

price of idocrase is not very high, as it is but little known 

among jewellers. 

Chrysolite and the green garnet are often substituted for 

but the first has a greater specific gravity and is 

HO 

idocrase ;


of a more vivid color ; 

the latter is harder, and likewise of 

greater specific gravity. 

The Italian ido erase, which is cut at Naples, is mostly 

called the Italian chrysolite. 

HAUYNE. 

The name of this mineral was given in honor of the 

celebrated French mineralogist, the Abbe Hatiy. It occurs 

in dodecahedral crystals, with brilliant faces ; also, in grains 

and massive ; it has a conchoidal fracture ; is transparent 

and translucent ; possesses a strong vitreous lustre ; its 

structure is imperfectly foliated. Its colors are indigo, sky, 

and smalt blue ; also, white, green, gray, and black. It 

scratches white glass and is scratched by quartz; white 

streak-powder; specific gravity is 2*47. Before the blow- 

and with 

pipe it loses its color and fuses into a porous glass, 

borax into a diaphanous glass, which turns yellow on cool- 

ing; it forms a jelly , 

with acids. 

It consists of lime, 

alumina, silex, protoxide of iron, sulphuric acid, and soda 

or potash. 

It is found in slacked basalt, and ejections of Mount Vesuvius 

; on Bodenmaise, on the Laach Lake, in Italy, and 

on the island of Tiree, Scotland. 

Hatiyne is not much known yet, but has lately been 

used for rings, ear-rings, brooches, &c. ; it is cut like ido- 

crase, but the price will always be high on account of its 

scarcity. 

LAPIS LAZULI. 

The name of this mineral is derived from the Persian 

language, and means blue color, or, with the Latin prefix, 

blue stone. The ancients were well acquainted with it, 

and have employed it as a substitute for other gems. The

LAPIS LAZULI. .323 

Greeks and Romans are said to have called it by the name 

of sapphire, denominating that with specks of iron pyrites 

the sapphirus regilus / Pliny called it the cyanus. It was 

formerly used as a strengthening medicine. 

Lapis lazuli very seldom occurs crystallized ; its regular 

form is the oblique four-sided prism ; it mostly occurs 

compact, and in grains and specks, 

with an uneven and 

conchoidal fracture; it is translucent on the edges; its 

lustre is nearly vitreous and shining ; structure foliated ; its 

color is fine azure-blue, with different shades, often inter- 

spersed with spots and veins of pyrites. 

It scratches glass, 

but is attacked by quartz and by the file ; its specific 

gravity is 2'3 ; before the blowpipe and on charcoal it with 

but with borax it fuses 

difficulty runs into a white glass, 

with effervescence into a limpid glass. 

It consists of lime, 

magnesia, alumina, and silex, with soda, protoxide of iron, 

and sulphuric acid. 

It is generally called in trade, the Armenian-stone. 

It is found in gangues of the older formations, and in 

Bucharia ; it exists in granite rocks, and is disseminated 

in all veins of thin capacity ; on the Baikal Lake it is found 

in solid pieces; also, in Siberia, Thibet, China, Chili, and 

Great Bucharia. 

Lapis lazuli is much used for jewelry, such as rings, 

pins, crosses, ear-rings, &c. The best pieces are generally 

cut out from larger lumps by means of copper saws and 

emery, then ground with emery on a lead wheel, and 

polished with rotten-stone on a tin wheel. The rocks 

which yield lapis lazuli, where it is contained in specks, 

are likewise cut for ornamental purposes, such as snuff- 

boxes, vases, candlesticks r cups, columns, cane-heads, &c. ; 

also, for architectural ornaments and stone mosaic; the 

larger specimens, having specks regularly disseminated on 

a white ground of the rock, are those selected for cutting.


The most important use of this mineral is that of furnish- 

ing the celebrated and beautiful pigment called ultramarine- 

blue, used by painters in oil, and said never to fade. The 

lapis lazuli takes a very high polish, but becomes dull again 

after being used for some time. It is sometimes imitated 

by lazulite' (azure-stone), or blue carbonate of copper, which, 

however, is not near so hard, and -effervesces- on testing 

with nitric acid. Those specimens having iron pyrites 

inclosed are difficult to polish well, on account of the un- 

equal hardness of the two minerals. 

Lapis lazuli has latterly been discovered in California, 

but the color of the mineral from this locality is very in- 

different, and its price is therefore much inferior to that 

from Persia. In Paris, the price is estimated at 300 francs 

per kilogramme. There are many engravings in lapis 

lazuli, such, for instance, as the Emblem of Peace a figure 

with a torch in one hand and a cornucopia in the other, and 

appearing to embrace military trophies, placed before her. 

The Chevalier d'Azara, Spanish minister in France, pos- 

sessed while there a very beautiful cameo of lapis lazuli, 

representing the head of Medusa, but without serpents. 

Maffei speaks of a Venus being carried by a she goat 

whipped by Love. 

The French crown-jewels contained some fine and gigantic 

specimens of lapis lazuli : one in the form of a boat of 

large dimensions, valued at 200,000 francs ; 

a sabre-handle 

given to Louis XVI., by Tippoo-Saib, valued at 6000 

a large vase, valued at 2600 francs. 

francs ; 

In 1855, at the Paris Exhibition, were numerous objects 

and carvings, exhibited by Rudolphi, which fairly compared 

with the antique relics of this species, both in material and 

in taste of execution. 

A marine shell carved from lapis lazuli was beautifully 

mounted by Morrel, and another chefcPoeuvre, in lapis lazuli,

LAPIS LAZULI. 325 

by Duponchel. A small round table of mosaic and lapis 

lazuli, which was a beautiful work by Jarry. 

A magnificent bagnivola of lapis lazuli, of very large size, 

and extremely pure and rich in color, was exhibited by Mr. 

Jones, in the London Exhibition, in 1851. 

Lapis lazuli has been well imitated of late, and, but for 

the touch, with much difficulty to be distinguished from 

the genuine, it is manufactured from bone-ashes and oxide 

of cobalt. 

The value of lapis lazuli, although depending upon its 

purity, intensity of color, and size, has nevertheless much 

diminished when compared with its former prices. 

. The Chinese, who have for a long time employed lapis 

lazuli in their porcelain painting, call the pure and skyblue 

stone zuisang, and the dark-blue, with disseminated 

iron pyrites, the tchingtchang, preferring the latter to the 

former ; they work the same for many ornaments, such as 

vases, snuff-boxes, buttons, and cups. 

In the palace which Catharine II. built for her favorite, 

Orlof, at St. Petersburg, there are some apartments entirely 

lined with lapis lazuli, which forms a most magnificent deco- 

ration. I have several slabs, three inches long, and of fine 

azure-blue color, in my possession. 

The production of ultramarine has been known since 1502, 

and was already employed, under the name of azurum ul- 

tramarinwtn, by Camillas Leonarus. 

The process of preparing ultramarine was known as 

early as the fifteenth century. The color is now mostly 

prepared at Rome, in the following manner : those pieces 

which are free from pyrites specks, are first calcined and 

pulverized ; the powder is then formed into a mass with a 

resinous cement (pastello), and fused at a strong heat this 

; 

is then worked with the hands in soft water, whereby the 

finest coloring particles are disengaged in the water,

326 A POPULAR TBEATISE ON GEMS. 

which will soon be impregnated with the blue color ; a fresh 

portion of water is then taken, and the same operation is 

continued until the remains are colorless. The ultramarine, 

after a short time, settles to the bottom of the vessels, and 

is carefully separated and dried. If the lapis lazuli be of 

the best quality, the product will be from two to three per 

cent. That color which remains yet in the mass is of an 

inferior quality, and is called the ultramarine ashes ; it is 

of a paler and more reddish color. 

Good ultramarine has a silky touch, and its specific gravity 

is 2*36. It does not lose its color if exposed to heat, but is 

soon discolored by acids, and forms a jelly. In order to 

distinguish the pure ultramarine from numerous spurious 

and adulterating coloring materials, such as indigo, Prus- 

to test the 

sian-blue, mineral-blue,

KTAJHTE. 327 

stuffs, several manufacturers have already 

been induced to 

engage largely in its preparation; and there is now a very 

extensive establishment in full operation by M. Guimet, 

three leagues from Lyons, who likewise claims the priority 

of its discovery: the royal porcelain manufactory at Meissen, 

in Saxony, also prepares it. The process" for making the 

artificial ultramarine, as it was first described by Gmelin, is 

here given, as it was published in the Annales de Chimie. 

The whole process is divided into three parts-: 

1. The pure hydrate of silica is prepared by fusing fine 

pulverized quartz or pure sand with four times its own 

weight of salt of tartar, dissolving the fused mass in water 

and "precipitating by muriatic acid ; also the hydrate of 

alumina is prepared from alum in solution, precipitated by 

ammonia. 

2. Dissolve the silex so obtained in a hot solution of 

caustic soda, and add to seventy parts of the pure silex 

seventy-two parts of alumina; then evaporate these substances 

until a moist powder remains. 

3. In a covered Hessian crucible, a mixture of dried sal 

soda, one part to two parts of sulphur, is heated gradually, 

until it is fully fused, and to the fused mass add small 

quantities of the earthy precipitate, taking 

care not to 

throw in fresh quantities until all the vapors have ceased ; 

after standing for an hour in the fire, remove the crucible, 

and allow it to cool. It now contains the ultramarine, 

mixed with an excess of sulphuret, which is to be removed 

by levigation ; and if the sulphuret is still in excess, it is 

to be expelled by moderate heat. Should the color not be 

uniform, levigation is the only remedy 

KYANTTE, SAPPAEE, DISTHENH. 

The name of this mineral is derived from the Greek, 

signifying blue, and was given to it on account of its blue


ccôr. It has been known for many centuries, having been 

cut by a Gernlan lapidary, Cornellius, in the reign of James 

I., under the name of sappare, by which it is yet known 

among the French jewellers. 

It occurs in masses composed of a confused aggregation 

of crystals, and in distinct crystals of four or eight sided 

prisms, much compressed, with two broad shining faces. 

The crystals are generally closely aggregated, and are cross- 

ing or standing on each other in a hemitropic form, so as 

to present a singular and curious aspect. Some of the 

crystals are curved, others are corrugated or wrinkled, as 

though they had been pressed endwise, or had not room 

to stretch themselves at full length ; others are pressed into 

triangular shapes, &c. It has a foliated structure ; uneven 

fracture ; is transparent and translucent ; possesses simple 

refraction of light ; its lustre is vitreous and pearly ; its 

colors are azure-blue, passing into light-blue or bluish-white 

and bluish-green. It scratches white glass, and is attacked 

by topaz or a good file ; yields a white streak-powder ; has 

a specific gravity of 3*63 to 3*67. It becomes electric by 

rubbing, and often exhibits positive and negative electricity 

in one and the same specimen; it is infusible before the 

blowpipe, but, with borax, fuses with difficulty into a trans- 

parent limpid glass : acids have no effect upon it. 

It consists of alumina and silex, sometimes combined 

with oxide of iron and water. 

The kyanite is found in micaceous, talcose, and argillaceous 

slate, at St. Gothard, in the Tyrol, and in Switzer- 

land; in Styria, Carinthia, Bohemia, Spain, and Siberia; 

also, in the United States, of the purest azure-blue color : 

large specimens in Litchfield, Haddam, and near New 

Haven (Connecticut) ; Chesterfield, Conway, Granville, 

Deerfield, and Plainfield (Massachusetts) ; Grafton, Nor- 

wich, and Bellows Falls (Vermont) ; 

Oxford (New Hamp-

TURQUOISE. 

shire) ; East Bradford, East Marlborongh, 

329 

smd Chester 

county (Pennsylvania) ; likewise, of a delicate light-blue, 

variously shaded, in Foster (Rhode Island). 

The kyanite has not yet been received as a favorite 

among the jewellers (perhaps from not being generally 

known by. them), or else it would long since have been 

cut for various ornamental purposes, more particularly in 

in this country, where the localities are so numerous and 

the color so beautiful. When well cut, it may be substituted 

for the sapphire. I indulge the hope that .some 

jewellers or lapidaries may take a hint from 4his remark. 

In France and Spain, it has for some years past been used 

for rings, brooches, and other jewelry. It is generally 

ground with emery on a lead wheel, and with pumice-ston.e 

polished on a wood plate, receiving the last polish with 

rotten-stone. The form it receives is cabochon or table 

cut. Usually, the best parts of good uniform colored specimens 

are picked out for cutting* 

The price of this stone depends upon the hardness, color, 

and polish : perfect specimens command a good price. 

Very fine cut specimens are brought from the East Indies, 

and sold in France as sapphires. 

TURQUOISE. 

The name of this mineral is probably derived from the 

country whence it was generally brought into market, 

which is Turkey. In ancient times it was used as a remedy 

for several diseases, and- was also worn as an amulet against 

disasters. It occurs in reniform masses and in specks; 

has a conchoidal fracture ; is opaque ; of a dull and waxy 

lustre ; its colors are blue and green, from sky-blue to 

apple-green, sometimes yellowish ; 

it scratches apatite, but 

not quartz nor white glass, and is easily attacked by the


file ; it has a white streak-powder ; its specific gravity is 

2'86 to 3*0; "it is infusible before the blowpipe alone, but 

loses its blue color and . becomes yellowish-brown but ; it 

fuses with borax into a limpid glass. 

Muriatic acid has no 

effect upon it. Consists of alumina, phosphoric acid, water, 

oxide of copper, and protoxide of iron. 

There are two kinds of turquoise used in trade, which 

differ materially in their composition, and are from differ- 

ent localities : 

1. Turquoise from the old rock, or true turquoise, which 

is generally . called Oriental turquoise, we receive from 

Persia, and is of a sky-blue and greenish color. 

2. Turquoise from the new rock, the occidental or bone 

and tooth turquoise, which is either dark-blue, light-blue, 

or bluish-green ; the surface of this mineral is sometimes 

traversed by veins which are lighter than the ground ; 

it is 

of organic origin, consisting, probably of colored teeth of 

antediluvian animals ; it owes its color, according to Bouil- 

. ' . ' O 

Ion Lagrange, to two per cent, of phosphate of iron, which 

is contained in it. It is easily distinguished from Oriental 

turquoise by its structure, internally foliated and striated, 

which is an indication of a bony composition ; it does not 

take so high a polish, is discolored in distilled water, dis- 

solves in acids, and is totally destroyed by aquafortis. Its 

localities are Siberia, Languedoc in France, and other 

places. 

True or Oriental turqupise is found in small gangues of 

bog-ore and silicious schist, in boulders, &c. A mineral 

by the name of kalaite, occurring as a coating to silicious 

sinter, in Silesia and Saxony, was some years ago dis- 

the mer- 

covered. Turquoise is brought to market by 

chants, of Bucharia, ready cut and polished; and in Mos- 

cow'it is wrought over, being ground on a lead wheel with 

emery, and polished with rotten-stone or pumice-stone on a

TURQUOISE. 

331 

tin wheel ; and its last and best polish is received from the 

jewellers, by rubbing with a linen rag and rouge. Since it 

is often traversed by fissures and cracks in the interior, 

it requires great caution in grinding. It is mostly cut in 

the form of cabochon ; also, as thick or table stones, and is 

used for numerous purposes in jewelry, such as rings, ear- 

rings, brooches, and also for mounting around the most 

precious gems. 

The price of turquoise has, for the last ten years, much 

decreased ; that of an Oriental is generally four times 

is worth 

higher than the occidental: one the size of a pea 

about five dollars; a good turquoise, sky-blue and oval-cut, 

five lines long and four and a half lines broad, was sold in 

France for two hundred and forty-one francs ; 

and a light- 

blue, greenish lustre, and oval-cut, five and a half lines long 

and five broad, was sold for five hundred francs ; whereas 

an occidental turquoise, four lines long and three and a half 

broad, brought only one hundred and twenty-one francs. 

Turquoise is very well imitated artificially (so much so as to 

render it difficult to discover the difference between that and 

the real), by adding to a precipitated solution of copper and 

spirits of hartshorn, finely-powdered and calcined ivory- 

black, and leaving the precipitate to itself for about a week, 

at a moderate heat, and afterwards carefully drying the 

same, and exposing to a gentle heat. This artificial tur- 

quoise is softer than the real, and cuts with a knife in 

shavings, whereas the genuine yields a white powder. The 

real turquoise displays in the daytime a sky-blue, and at 

night a light and greenish color ; 

and resists the fire. 

is not attacked by acids, 

In the museum of the Imperial Academy at Moscow, is 

a turquoise more than three inches in length and one inch 

in breadth. 

A jeweller at Moscow is said to have had in his posses-


sion a turquoise two inches long, in* the form of a heart. 

This formerly belonged to Nadir Shah, who wore it as aE 

amulet, for which he asked five thousand rabies. 

A short time ago, I beheld, at a sale, one of the largest 

and most splendid turquoises, which was one inch in size, 

and of a blue color. 

Major McDonald's collection of turquoises, from Arabia, 

exhibited at the London Exhibition, in 1851, was very 

beautiful ; it consisted of two hundred specimens, cut and 

polished. They differed very little from the Persian tur- 

quoises. He discovered several localities in the country of 

Sonalby, sixteen days' journey northeast of Suez, but all 

were within a range of forty miles, and upon a mountain 

range, at from five thousand to six thousand feet of elevation. 

Some turquoises were found in situ, but most of them 

were collected from the ravines descending the mountain 

chain. The rock is a reddish sandstone, composed of quartz 

grains, belonging to the paleozoic rocks. Their hardness 

is equal to that of agate. The nodules of turquoise form 

groups, almost like currant seeds, in the sandstone. There 

may be observed in this collection, veins and small concretions 

from one tenth to one twentieth of an inch in thick- 

ness, which cut across the bed of sandstone like small 

threads ; in color they vary from an intense blue to a bluish- 

white. 

NATROLITE. 

This mineral has been discovered of -late years, and re- 

ceives its name from the Latin natron, soda, given to it on 

account of that alkali being, contained in it; it occurs reni- 

form, botryoidal, and massive, such as mammillary, and in 

the alternate zones around the centre; it has a splintery 

fracture; is translucent on the edges; of a pearly lustre: 

its colors are white, yellowish-white, or reddish-brown, and

they often alternate in different layers ; 

glass, but is scratched by felspar; 

powder; its specific gravity is 2*16; 

blowpipe into a colorless* spongy glass ; 

FLUOR SPAR. 333 

it scarcely scratches 

has a white streak- 

it fuses before the 

it consists of soda, 

alumina, silex, and water, sometimes a little oxide of iron. 

Its localities are Switzerland, Bohemia, Saxony, Scotland, 

and Nova Scotia. Natrolite, on abcount of its susceptibility 

of a high polish, has been used for rings and other 

ornaments in jewelry, but has not yet been hi much de- 

mand, and its value is also very inconsiderable. 

FLUOR SPAR. 

This mineral was well known to the ancients, but did not 

attract particular attention until the sixteenth century, 

when it was introduced as a flux. As early as 1670, the art 

of etching on glass by means of fluor spar was practised at 

Nuremberg. 

Fluor spar occurs mostly in crystals of various forms, the 

principal of which is the octahedron with its varieties, the 

cube and the rhomboidal dodecahedron ; also, massive and 

in specks ; it has an uneven or splintery fracture ; is trans- 

parent or translucent on the edges ; possesses simple refraction 

of light ; a vitreous lustre ; its colors are green, yellow, 

gray, blue, and white ; also purple and red, in all their 

various shades, from the violet to the rose-red. 

It scratches lime, but not glass ; yields to the knife ; has 

a white streak-powder; its specific gravity is 3*14 to 3'17; 

it becomes electric by rubbing ;* before the blowpipe it 

fuses with ebullition into an opaque globule, but with 

when pulverized and treat- 

borax, into a transparent glass ; 

ed with heated sulphuric acid, it emits fluoric acid gas, 

which is employed in etching on glass ; phosphoresces when 

thrown on hot iron ; it consists of fluoric acid and lime.


From the variety and beauty of its colors, it is known, when 

cut, in trade, under the various names of false emerald, 

false amethyst, false ruby, and false topaz, according to the 

color it exhibits. It is mostly found in metalliferous veins, 

and very rarely in the newer formations. Its localities are 

in Baden, Bohemia, Saxony, St. Gothard, at Derbyshire 

and Devonshire, in England, and the United States, in the 

last of which countries it occurs of most beautiful colors in 

fine crystals ; from a lately-discovered locality at Rnssy, in 

St. Lawrence county, State of New York, I have specimens 

of crystals two feet long and five wide. It is found in Illi- 

nois, seventeen miles from Shawneetown ; Blue Ridge, 

Maryland ; Smith county, Tennessee ; at Franklin Furnace, 

and Hamburgh, New Jersey; Saratoga Springs, and at 

Alexandria, New York; Middletown and Huntingdon, 

Connecticut ; Thetford and Southampton lead mines, Mas- 

sachusetts, and on the White Mountains, New Hampshire. 

Fluor spar is cut for ring-stones and shirt-buttons, and 

particularly 

in such forms as are intended to be substituted 

in Derbyshire there have been large mills 

for other gems ; 

for grinding, cutting, and polishing the flour spar into vases, 

cups, obelisks, plates, candlesticks, &c., ever since 1765, 

and there are now more manufactories, principally at 

Derby. That fluor spar which may be called the nodular 

variety, and the colors of which run in bands or zones, is 

only found in a single mine near Castleton, Derbyshire, and 

is known by the technical name of Derbyshire-spar 

John ; it is used for various ornaments, 

or Blue 

to be met with all 

over the world, in parlors or mineral collections. In order 

to heighten the various colors in the ornamental specimens, 

before they are polished, they are heated to a certain de- 

gree, when the dark spots, or tints, disappear, and the 

colored bands become more distinct, and assume a peculiar 

purple or amethystic hue.

MALACHITE. 335 

Fluor spar is often intermixed with lead ore, called galena, 

which produces, when polished, a beautiful appearance. 

Ornaments of fluor spar still command a high price, which, 

however, depends a good deal on the perfect qualities of 

the various specimens, their color, gize, &c. 

A translucent variety of fluor spar, called chlorophane 

(found in Cornwall, England, in Siberia, and principally in 

the United States, at New Stratford, Connecticut), is of 

beautifully variegated colors, but principally blue, violet, and 

green ; it is chiefly interesting on account of its phosphorescence 

; when put on hot iron in a dark room, it emits a 

most beautiful emerald-green light. 

One of the first locali- 

ties of chlorophane discovered in this country, was at Shee- 

konk, Massachusetts, near the summer residence of the 

Hon. Tristam Burges, about one and a half miles from* 

Providence. It is massive, opaque, and of a deep purple 

color. It phosphoresces readily on being projected upon a 

moderately-heated shovel, when it loses its color and becomes 

white. It also occurs of a crystalline structure in 

Wrentham, Massachusetts, near the Cumberland and Rhode 

Island line, in the vicinity of Diamond Hill. A beautiful 

vase of Derbyshire-spar, as also crystalline groups, may 

be seen in the collection of the New York Lyceum of 

Natural History. 

MALACHJTE. 

The name of this mineral is from the Greek, alluding to 

its color ; it was well known to the ancients ; Theophrastus 

called it the pseudo-emerald ; it was worn by many as 

an amulet. 

It occurs tuberose, globular, reniform, mainmillary, an


lustre ; 

and has an emerald or verdigris green color, alter- 

nating sometimes in stripes of different shades of green. 

It scratches lime, but not glass ; its streak-powder is of 

lighter color than the mineral; its specific gravity is 3*67 ; 

before the blowpipe, it decrepitates and turns black ; with 

borax, it is reduced to a* metallic grain ; 

it effervesces with 

nitric acid ; is dissolved, and forms a blue color with am- 

monia ; it consists of oxide of copper, carbonic acid, and 

water. 

Malachite is found in various rocks, primitive as well 

as secondary, in gangues and strata. The finest specimens 

are obtained in Siberia, Tyrol, France, Hungary, Norway, 

Sweden, England, Bohemia, and the United States, at a 

great number of localities, but either in small specimens, 

*or as a coating of other copper ores, which will ever ren- 

der jt useless for ornamental purposes. The principal locali- 

ties in this country are in New Jersey, Maryland, Connecti- 

cut, and at the various copper-mines ; it is also found in the 

island of Cuba, from which place I have seen some good 

compact specimens. 

Some very fine specimens of compact malachite from 

Siberia, were presented to the New York Lyceum of 

Natural History, by' Charles Cramer, Esq., of St. Petersburg. 

I have also seen some excellent specimens of mala- 

chite in the collection of Dr. Martin Gay, at Boston ; Dr. 

Chilton, of New York, &c. 

Malachite, when cut, takes a high polish, 

which well 

adapts it for various ornaments, such as rings, pins, earrings, 

&c. Snuff-boxes, candlesticks, mosaics, &c., are likewise 

made from it. In general, the specimens are assorted, 

and the best pieces cut on a leaden wheel with emery, and 

polished with rotten-stone on a tin plate. 

cirnens are used for table plates and vases. 

Very large spe 

The value of the malachite is not high, being very abun-


dant ; yet much depends upon the size of the various specimens. 

At St. Petersburg, a very large slab, said to be 

in the collection formerly belonging to Dr. Guthrie, thirtytwo 

inches long, seventeen inches broad, and two inches 

thick, was valued at twenty thousand francs. Many rooms 

in several European palaces are laid out with malachite ; 

and the Mineralogical Museum, at Jena, possesses a large 

collection of malachite, which was presented by the Grand 

Duchess of Saxe Weimar, a Russian princess. 

An apartment in the Grand Trianon, at Versailles, is 

furnished with pier and centre tables, mantel-pieces, ewers 

and basins, and enormous ornamental vases of malachite, 

the gift of the Emperor Alexander to Xapoleon. 

The malachite furniture exhibited by the Russian government 

at the London Exhibition, excited so much admira- 

tion and was sold at such high prices, that the author con- 

siders himself justified in copying a part of the report by 

the jury on inlaid work in malachite : 

" Malachite is a peculiar mammilla ted or stalagmitic form 

of the green carbonate of copper, chiefly found in an avail- 

able state for inlaid work, in a very few localities in 

Siberia, and lately in South Australia. It has long been 

employed in Russia in this manufacture. The mineral is 

remarkable for its fine emerald-green color (often present- 

ing several distinct shades in the same specimen), its bril- 

liant and silky lustre, and compact texture. It is softer 

than marble, very much heavier, and by no means so easily 

worked, owing to its brittleness and the concentric arrangement 

it generally presents. It can rarely be found in 

masses weighing more than ten to twenty pounds, and 

good specimens have a very high value, as the finer kinds 

are used exclusively for decorative purposes. 

" The most important locality at present known for the 

finer kinds of Siberian malachite, is in the copper ground


of Nijug Tagilsk, in the government of Ekaterinenburg, on 

the river Tura, a tributary of the Irtish, on the Siberian side 

of the Uralian mountains, in latitude 57J N., longitude 56 

E. In a mine at this place, belonging to Messrs. Demidoff, 

Sir Roderick Murchison has described an immense mass of 

malachite, which at the time of his visit, a few years back, 

had been recently discovered at the depth of two hundred 

and eighty feet, strings of green copper conducting to it ; 

and these strings increasing in width and value, were found 

to terminate in a vast irregular botryoidal mass, estimated 

to contain not less than half a million of pounds of this 

valuable mineral. The larger blocks, when exposed to the 

air, break up into smaller fragments, rarely weighing more 

than from one to four pounds. 

" It is by no means a modern application of this material, 

to employ it in inlaying or veneering for decorative purposes; 

and few palaces or large public museums in the 

principal capitals of Europe, are without specimens, mark- 

ing the progress of its manufacture from time to time, and 

generally regarded, from their great rarity, cost, and beauty, 

as worthy of being made imperial and royal presents. It 

is, however, only lately that Messrs. Demidoff, the owners 

of the mine in which the mineral occurs, have established 

in St. Petersburg a manufactory, where, after numerous 

trials and the expenditure of much capital, labor, and in- 

such works 

genuity, it has been found possible to produce 

as those sent to the London Exhibition, and in testimony 

of the magnitude and importance of the objects exhibited, 

their extraordinary beauty and richness, the excellence of 

the production, and the application of the various new 

methods of manufacture, Messrs. Demidoff have been 

awarded the highest premiums. These are chiefly seen in 

the construction of the doors, and more especially in the 

ingenious and beautiful manner in which the pattern is


adapted to the material, the detached pieces of mineral 

being fitted to each other so as to preserve the pattern ; 

they may also be noticed in the nature of the cement, 

which being mixed with broken fragments of the malachite 

itself does not interfere with the plan, or in any way injure 

the effect of the whole. 

" 

The working of malachite on a large scale is extremely 

tedious and laborious, and the mode of operation is too 

long to detail in this treatise. 

" The quantity of malachite obtained from the mine and 

brought into market annually is very small, and the price 

of the raw material is considerable, it ranges from twelve 

to seventeen shillings sterling per pound, according to color 

rather than veining, the darker colors being cheapest; 

there are four shades quoted, denominated respectively, 

foncee, ordinaire, claire, and pale ; but these are also sub- 

divided, the two first into ronde and longv.e, the others 

into ronde, longue, and tachetee. A large proportion of 

the malachite in the specimens exhibited was of very good 

color, and the average value probably exceeded fifteen 

shillings sterling per pound. 

"The objects exhibited consisted of a pair of fold- 

ing-doors, several vases, a chimney-piece, a table, a set of 

chairs, and sundry smaller articles; of these, the doors and 

vases were at once the most important and the most highly 

finished, and it is understood that the former required the 

constant labor of thirty workmen employed by day and 

night during a whole year. They were most skilfully and 

and beautifully planned, and the workmanship was in all 

respects admirable." 

There are fluted Corinthian columns of malachite in 

some churches in St. Petersburg, and many other large 

ornaments of large slabs of malachite in the palace of the 

King of Prussia, at Potsdam.


A large oblong table, inlaid with malachite, partly Russian 

and partly Australian, was also exhibited by a manufacturer 

of Paris, with specimens of azurite (blue carbonate 

of copper), but were all put in the shade by the Russian 

articles. 

SATIN SPAR. 

This mineral occurs stalactiform, globular, reniform, and 

massive ; it is of a fibrous texture (that is, of fine delicate 

fibres closely adhering together), a pearly lustre, and is 

translucent on the edges ; the colors are snow-white, yel- 

lowish-white, or pale-red, colored by 

metallic oxides. It 

scratches gypsum, but not glass ; specific gravity, 2*70 ; be- 

comes electric by rubbing ; before the blowpipe is infusible, 

and changes into quicklime, but borax reduces it to a clear 

glass. It effervesces and dissolves with nitric acid; and 

consists of lime and carbonic acid. Satin spar is called by 

mineralogists fibrous limestone, and is found in the coal 

formations, and in the cavities of several limestones. The 

finest specimens are found in Cumberland and Derbyshire, 

England ; in Hungary ; and in the United States, near 

Baltimore, in Pennsylvania, also at Westfield and Newburyport, 

Massachusetts, where splendid specimens five inches 

long are obtained, according to Professor Hitchcock. It 

takes a fine polish, and is distinguished by its extraordinary 

fine satin lustre, and is therefore used for various articles of 

jewelry, such as ear-rings, necklaces, beads, and also for 

inlaid work ; large specimens are used for snuff-boxes. 

Satin-spar beads have been in great favor as necklaces 

and ear-rings, and were sold a few years ago in England at 

very high prices. In modern times, the satin beads or 

pearls have been imitated to a great extent in France and 

Germany, in white and deep-yellow colors : glass beads, of 

a bluish-white tinge, and hollow, are made to imitate the

ALABASTER. 341 

reflection of the satin spar, by means of the scales of a 

small river-fish called the bleak, that are suspended in dissolved 

isinglass, and dropped into the bulbs, which are then 

turned in all directions in order to spread the solution 

equally over their interior surface ; in this way the glass 

bulbs assume the natural color and brilliancy of satin spar ; 

they are harder, however, and it is easy to detect them on 

that account. 

Fine specimens may be seen at the New York Lyceum 

of Natural History, also in the collection of Dr. Gay, of 

Boston. 

Satin gypsum, which bears the greatest resemblance to 

satin spar, and only differs in its chemical constituents (hav- 

ing sulphuric acid, instead of carbonic, as a component part), 

is much used for the same kind of ornamental purposes, and 

is more abundant over the world. I have seen very splen- 

did specimens at South Boston, in the beautiful collection 

of minerals belonging to Francis Alger, Esq., who brought 

them from Nova Scotia, and who (as also Dr. C. T. Jack- 

sou) has given so valuable a description 

treasures of that province. 

of all the mineral 

Satin gypsum is, however, much softer than satin spar, 

and is much easier scratched ; for which reason it is not 

so generally employed. 

ALABASTER. 

This mineral is a compact gypsum, and occurs massive, 

with a compact fracture ; it is translucent ; has a glim- 

mering lustre, and its colors are white, reddish, or yellowish. 

The purest kinds of this mineral are used in Italy for 

vases, cups, candlesticks, and other ornaments. It is found 

at Castelino, in Tuscany, thirty-five miles from Leghorn, 

at two hundred feet below the surface of the earth.


The yellow variety, called by the Italians, alabastro ago* 

tato, is found at Sienna ; another variety of a bluish color, 

obtained at Guercieto, is remarkably beautiful, being 

marked with variegated shades of purple, blue, and red. 

The above alabasters are carbonates of lime. 

The principal manufactory of alabaster ornaments is at 

Valterra, thirty-six miles from Leghorn, where about five 

thousand persons live by this kind of labor. In making, 

they require great care, and must be preserved from dust, 

as the alabaster is difficult to clean. Talcum, commonly 

called French chalk, will remove dirt, but the best mode 

of restoring the color, is to bleach the alabaster on a grassplat. 

Gum water is the only cement for uniting broken 

parts. 

Plaster of Paris is likewise, a compact gypsum, but 

contains a small portion of carbonic acid, which makes it 

effervesce when treated with acids. It was formerly ex- 

ported only from Montmartre, near Paris, hence its name ; 

it is much used in ornamenting rooms in stucco, in taking 

impressions of medals, in casting statues, busts, vases, 

time-piece stands, candelabras, obelisks, and for many other 

purposes. 

The common plaster of Paris is ground after being cal- 

cined ; 

and in this condition it has the property of forming 

a pliable mass with water, which soon hardens, and assumes 

the consistency of stone. 

Oriental alabaster is not a sulphate but a true carbonate 

of lime, and on account of its peculiar tint and trans- 

parency, and as it appears 

that it was formed similar to 

stalagmite, it was called by the ancients, alabaster; the 

large vase of this Oriental alabaster which was so justly 

and so much admired by the thousands of spectators at the 

London Exhibition, was executed by Dallamada, of Rome. 

It was really a magnificent piece of workmanship, being

AMBEE. 348 

from a large block and the whole work of one entire piece, 

the vase, the handles, which consisted of serpents, along 

with the tazza and the extremely fine polish, displayed the 

great ingenuity of the master. 

A hollow altar of Oriental alabaster, provided with a 

lamp and intended to show the remarkable transparency 

of the material, and of excellent workmanship, along with 

a great many statues and groups of life-size figures, were 

exhibited both in the London and New York Exhibi- 

tions. 

A3IBER. 

This gem was known to the inhabitants of remote ages ; 

the Phoenicians sailed to the Baltic (the Glessany islands), 

for the sole purpose of obtaining amber, which they 

wrought into chains and other ornaments, that were sold 

to the Greeks, who called the same electron. In the Trojan 

war, as Homer reports, the women wore necklaces of 

amber. Its electric properties were likewise known, for 

Thales was so much surprised at that phenomenon, that he 

attributed it to a soul in the amber ; and Pliny says that 

amber is revived by heat, the nature of electricity not 

being understood. It was also worn as an amulet, and 

used for medicine. The ancients could not agree as to its 

origin : Philemon, according to Pliny, classed it as a fossil ; 

Tacitus, however, judging from the insects held in it, concluded 

it must be a vegetable juice, whence its name in 

Latin, succinum, or juice. Many naturalists have, until 

lately, considered amber as a mineral; 

but it has been 

satifactorily proved by Schweigger and Brewster, from its 

chemical characters, and polarizing light, to be a gum-resin, 

and that it is the juice of a tree, called the amber-tree, now 

extinct. 

Amber occurs in nodules or roundish masses, from the


size of grains to that of a man's head ; and sometimes in 

specks; it has a conchoidal fracture; is transparent and 

translucent ; possesses single refraction of light ; a resinous 

lustre in a high degree : its colors are wine and wax 

yellow, greenish or yellowish white, or reddish-brown ; 

sometimes the colors vary in layers. It scratches gypsum, 

but is attacked by carbonate of lime ; its streak-powder is 

yello wish-white ; it has a specific gravity of 1*08 to 1*10; 

it becomes electric by rubbing. Before the blowpipe it 

burns with a yellowish and bluish green flame, emitting at 

the same time a dense and agreeable smoke, and leaving a 

carbonaceous residuum; 

heated oil softens and makes it 

pliable ; it does not melt as easily as other resins, requiring 

51 7 Farenheit ; it yields by dry distillation an acid which 

is called succinic acid, also an essential oil, known by the 

name of oil of amber, and in the retort remains a brown 

mass, called the resin of amber, which is used in the arts 

as amber varnish ; any essential oil, or spirits of turpentine 

may be used for procuring the resin ; 

fat oils dissolve 

amber perfectly; its elementary constituents are carbon, 

hydrogen, and oxygen, with some lime, alumina, and 

silex. 

Amber is found either thrown up by the sea, or in the 

small rivers near it ; 

sometimes in alluvial deposits of sand 

or gravel in the vicinity of the sea, or in bituminous forma- 

tions, such as lignite, bituminous wood, or jet, where crystallized 

minerals are at the same time found, such as iron 

pyrites, &c. 

Its geological distribution is in the green-sand formation, 

or, according to De la Beche, the stratified rocks, between 

the third and fourth large group. 

Amber occurs in the greatest abundance on the Prussian 

coast, in a bed of bituminous coal, where it is washed out 

or cast ashore during the autumnal storms on the coast of

AMBER. 345 

Pomerania and Prussia proper, between Konigsberg and 

Dantzic ; it is also obtained there by sinking 

a shaft into 

the coal, and is mined in a systematic way. All along the 

line of the Baltic coast, at Corn-land, Livonia, Pomerania, 

and in Denmark, it is picked up. On the Sicilian coast, 

near Catania, sometimes very peculiarly tinged blue, it is 

also found. In Greenland, at Hasen island, it occurs in 

brown coal. Near Paris it occurs in clay. It is also found in 

China. One of the largest specimens ever met with on the 

Baltic was found in 1811, measuring fourteen inches in 

length by nine inches in breadth, and weighing twenty-one 

pounds. 

I had in my own coUection, in the year 1831, a splendid 

wax-yellow amber, from the Baltic, which measured about 

sixty cubic inches, and weighed nearly two pounds. It is 

also found on the Danish coast, and in Greenland, Sicily, 

Monrovia, Poland, France, and the West Indies. A sailor 

is said to have found a remarkable specimen, eighteen 

inches in length, in a singular manner ; 

the discoverer acci- 

dentally seated himself on it, when he became so attracted 

to the amber, excited by his natural heat, that it was with 

some difficulty he could detach himself from it. 

In the United States we find amber at Cape Sable, in 

Maryland, in a bed of lignite, 

in masses of four and five 

inches diameter ; also, near Trenton, and at Camden, New 

Jersey, where a transparent specimen, 

several inches in 

diameter, was found. According to Professor Hitchcock, 

it is found at Martha's Vineyard, Gayhead, and at Nantucket. 

At the latter place, a light-colored specimen was 

found, of three or four inches diameter, which is 

collection of T. A. Green, Esq., of New Bedford. 

in the 

The production of amber depends upon the position of 

the respective localities ; whether it is found among sand 

and gravel, in mines called amber mines, or in the sea, on


the shore, or in smaller rivers near the sea-coast ; and the 

modes of collecting are threefold : 

1. The amber mines, which are numerous in Prussia, are 

wrought like other mines, and explored to a depth of more 

than one hundred feet. Shafts are constructed for raising 

the product from the interior of the mines ; the miners dig 

until they reach the amber vein, which is generally found 

after passing a stratum of sand and a bed of clay of twenty 

feet thickness, and another stratum of decomposing trees or 

come then to 

lignite, which may be fifty feet through ; they 

the pits, which the characteristic color of the soil is the best 

indication to search for. 

2. The second mode of collecting amber is practised, 

generally after a storm, by the fishermen, who either wade 

into the water, provided with leather dresses, 

to their 

necks, or use small boats, and find at the depth of three 

fathoms the floating amber. 

3. It is mostly, however, collected in large quantities on 

the shore, after having been thrown up by severe storms. 

The amber fishermen are, by practice, pretty well skilled 

in finding out the spots where the largest quantities may 

be obtained. 

Amber from the mines does not essentially differ from 

that of the sea, excepting that the former is rather more 

brittle, and is often covered with an earthy crust. 

The amber is assorted before it comes into the hands of 

the lapidary or merchant, and according to size and clear- 

ness of color, it receives different technical names. Thus, 

there are 

1. The exquisite specimens, which are perfectly pure, 

transparent, and compact, weighing from five to six ounces 

or more ; these are employed in larger ornaments and spe- 

cimens of the arts, and bring the highest price. 

2. The ton stones, which weigh from a quarter of an

AMBER. 347 

ounce to four ounces; the largest or purest pieces of which 

are used for jewelry, and the impure for incense or med- 

icine. 

3. The nodules are still smaller. 

4. The varnish stones are still smaller than the former, 

but are very pure and hard, so as to be easily pulverized, 

and are used for varnishes, sealing-wax, &c. 

5. The sandstones are very small, opaque, and perforated 

pieces. 

6. The lumps are large but impure specimens, unfit for a 

lapidary's use ; they are sold as specimens, or employed as 

incense, or for the manufacture of succinic acid. 

7. Refuse are those pieces which fall off at the lapidary's 

bench. 

The pure amber receives from the lapidary distinct 

such as 

names, according to the shades of color it possesses, 

egg, pale, and light yellow, and so into its brownish shades. 

The assorted amber is treated according to the various 

purposes it is intended for, and receives its requisite form 

by cleaving with an appropriate instrument, by which, also, 

the external crust is removed. It is generally believed that 

the worse the crust is in appearance, the more beautiful is 

the interior of the amber. 

Amber, taking a very high polish, is employed 

for a 

great many purposes of jewelry, and for various ornaments, 

such as beads, necklaces, bracelets, ear-rings, buttons, rosa- 

ries, mouth-pieces for pipes, cane-beads, snuffboxes, work- 

boxes, &c. It is generally wrought on the turner's lathe, 

by steel instruments, and is easily bored ; it is polished on 

a leaden wheel, with pumice-stone, then with linen or a hat- 

body and rotten-stone, and lastly by rubbing it with the 

hand. Common specimens are polished with a linen rag, 

chalk, and water. Beads of amber must be drilled before 

receiving the facets. In cutting and working amber, care


must be taken not to overheat it by friction, as it will then 

be liable to crack. Amber has occasionally been cut into 

cameos, busts, images,

AMBER. 349 

little; whereas copal, under similar circumstances, melts 

and falls in drops, which become flattened." My own ex- 

perience has taught me the following distinguishing charac- 

teristics : first, the electrometer, a small instrument com- 

posed of a brass needle, suspended on a pin, is the most esse^ 

tial distinguishing guide, for amber, on being rubbed, 

will excite the instrument about ten degrees more than 

copal ; secondly, amber, on being brought before the fire, 

requires a moderately high temperature for melting it, and 

exhibits no kind of ebullition, whereas copal easily liquifies, 

burns with much smoke, and decrepitates more than 

amber. 

Amber is likewise adulterated by gum arabic, gum thus, 

shellac, and glass pastes. The last can easily be distin- 

guished by their hardness, and the others by their solubility 

in hot water. 

Amber very frequently has inclosed within it insects, 

such as flies, beetles, &c., in a state of complete preservation. 

Such specimens are much sought for, and command 

a very high piice ; 

and on that account the adulterations 

are mostly practised, and in the following manner : either 

by boring a hole in the amber, introducing the beetle, 

filling 

it up with pulverized gum-mastic, and then let- 

ting it melt over a charcoal fire ;*or by melting the amber, 

throwing in the insects, and letting it cool. The former 

adulteration may easily be detected, since the mastic will 

never be able to combine closely with the amber, and shows 

more or less cracks and fissures ; but the latter is scarcely 

to be detected, without a scientific investigation of the in- 

closed insects, which in the natural specimens do not exist 

in the present world, being called antediluvian, or extinct 

species of animals. 

The most extensive use of this elegant material is for the 

manufacture of the mouth-piece, an essential constituent ol


Amber mouth 

the genuine Meerschaum and Turkish pipe. 

pieces have always been in great request in the East, where 

but in the United States a fash- 

they command great prices ; 

ionable taste, similar to other countries, has sprung up of 

late, which bids fair to outvie the East. No young man of 

any pretensions to smoking cigars, can do so without his 

meerschaum and amber cigar-holder. The dearer he pays 

for this luxury, the more respected he considers himself. 

There is a current belief in Turkey, that amber is incapable 

of transmitting infection, and as it is a great mark of 

politeness to offer the pipe to a stranger, this supposed 

negative property of amber accounts, in some measure, for 

the estimation in which it is held. 

There is evidence of the extreme antiquity of amber in 

the fact that the Phoenicians imported it from Prussia. 

Since that period it has been obtained there uninterruptedly, 

and no diminution in the quantity annually collected has 

been perceived. If we incline to the theory that amber is 

a species of wax or fat, having undergone a slow process 

of putrefaction, based on the fact that chemists are able to 

convert ceraceous or fatty substances into succinic acid, by 

inducing oxidation artificially, the belief must be entertained 

that a new formation of amber is constantly going 

on, which theory is strengthened by the different appearance 

of the varieties of amber, which seem to exhibit the 

successive stages of its development and decay. On the 

other hand, Tacitus, in his Germania, states that it is a resin, 

exuded by certain conifers, traces of which are frequently 

observed among the amber. Certain it is that, at one 

time, amber must have been liquid, from the simple fact 

that numerous small animals are found inclosed within it ; 

these, for the most part, are insects belonging to an extinct 

species of arachnidse. A specimen containing the leg of 

a toad was seen among an extensive collection at the Lon-

AMBER. 351 

don Exhibition, and it is said that in China, amber contain- 

ing insects is of frequent occurrence. From the fact that 

amber and fossil wood have been found in alluvial deposits 

of sand and clay, and associated with ocean shale and iron 

pyrites, at a depth of sixty feet, it is the author's firm belief 

that the marine amber is a subsequent formation to the 

terrestrial amber. That Pliny already took it for a vege- 

table production, may be inferred from his : 

expression 

" 

quod arboris succura, prisci nostri credidere." 

The different kinds of amber are distinguished by varie- 

ties of color and degrees of transparency. All shades of 

yellow, from the palest primrose to the deepest orange, or 

even brown, are its constant colors. In point of clearness, 

amber varies from vitreous transparency to perfect opacity; 

some are nearly as white as ivory, which is, however, a rare 

occurrence. If there are two layers together, the trans- 

parent and opaque varieties, it is used for cutting cameos. 

An inquiry naturally suggests itself as to which of these 

varieties of amber is the most valuable. It is self-evident 

that this must depend, as in the diamond, upon the size and 

the uniformity of the pieces. Besides, as all varieties ex- 

cepting the white, which has its special uses, are equally 

applicable for manufacturing purposes, it follows that the 

value of any particular sort must depend in a great measure 

upon its variety. The straw-yellow, slightly translucent 

variety is the most rare, and is that which the Orientals 

prefer to all others, and which they purchase at extrava- 

gant prices. Every piece of that quality is exported to 

Turkey, in the raw or manufactured state. 

Among the exquisite specimens of amber in the London 

Crystal Palace, were four most splendid imaums, or round 

amber mouth-pieces, richly ornamented with brilliants the 

; 

shortest two, which in smoking are pressed against the 

lips, were each worth three hundred pounds sterling, and


were each of that peculiar color and degree of transparency 

which approaches nearest to the Turkish ideal of beauty. 

The two longer mouth-pieces were of a different form, and 

although not of so good a color, nor enriched with as many 

diamonds, were still valued at two hundred pounds sterling 

each. 

A large specimen obtained from the amber pits in Prus- 

sia, weighing six pounds, 

and another marine amBer and 

waterworn, weighing four and a half pounds, owned by Mr. 

Wolff Manheimer, of Konigsberg, Prussia, were likewise 

at the London Exhibition. 

At the Royal Museum in Berlin, is a large mass of amber, 

weighing eighteen pounds. 

In the kingdom of Ava, a mass nearly as large as a 

child's head was found some years ago, which was inter- 

sected in various directions by veins of crystallized carbon- 

ate of lime. 

Amber is very fusible and liable to be broken. To join 

the broken pieces, and to unite them in such a manner as 

to look and wear as well as new, the author of this treatise 

recommends the use of soluble glass (either the silicate of 

soda, or silicate of potash), which is applied to the fissure 

or fractured part, after which the united parts are tied with 

with a twine and kept so for some days ; it will then remain 

firm. Thick shellac varnish is also highly recommended : 

dissolve bleached shellac in ninety-five per cent, alcohol, 

to the consistency of syrup, touch the broken parts with 

the varnish, tie them with twine, and leave the article in 

a warm place for some days before using. 

Amber powder made into a paste with thick shellac 

varnish and moulded, may easily be made into a variety of 

forms, and represent genuine amber. 

The most extraordinary collection of specimens of amber 

may be seen in the cabinet at Dantzic. A specimen of

JET. 353 

amber of fifteen pounds weight is preserved in the cabinet 

at Berlin. The inhabitants of Colberg, in 1576, presented 

to the Emperor Rudolph II. a specimen weighing eleven 

pounds. 

JET. 

This mineral occurs massive ; 

has a conchoidal fracture ; 

is opaque; has a shining lustre; and is of a jet, or pitch- 

black color. It is pretty soft, and yields to the knife ; 

its hardness is 1* to 2*5; specific gravity, 1*29 to 1*35; 

it burns with a greenish flame, and emits a strong bitumin- 

ous smell. In trade it is also called black amber, or pitch 

coal. It is found in the brown-coal formation, the plas- 

tic clay, and the lias, with lignite and amber, in England, 

France, Silesia, Hesse, Italy, Spain, and Prussia. 

Jet bears a high polish, and is wrought into necklaces, 

ear-rings, crosses, rosaries, snuff-boxes, buttons, bracelets, 

and particularly mourning jewelry. It is at first generally 

assorted to select the best pieces, most suitable for working ; 

such as are free from iron pyrites, lignite, and have no 

cracks or fissures. It is then turned on a lathe, and like- 

wise on horizontal sandstone wheels, which run unequally 

on their periphery, by which the various specimens may be 

cut and polished at the same time. During the operation 

the jet must be moistened with water, else it may crack 

from being overheated. It is polished with rotten-stone or 

crocus martis and oil, on linen or buckskin ; and lastly by 

the palm of the hand. 

The manufacturing of jet ornaments was formerly a con- 

siderable branch of industry in France, where, in 1786, the 

department de PAube occupied twelve hundred workmen ; 

but at the present time it is not worn, and the black enamel 

is substituted for it. 

Jet is a species of bituminous coal, which has several


names, such as common coal, black coal, cherry coal, splint 

coal, cannel coal, jet, lignite, &c.; more properly, how- 

ever, it is a variety of cannel coal, but it is much blacker, 

and has a more brilliant lustre. It occurs in detached 

pieces, in clay, on the coast near Whitby, in Yorkshire, 

and is the gagates of Dioscorides and Pliny, a name de- 

rived from the river Gagas, in Syria, near the mouth of 

which it was found. 

Cannel coal, which comes nearest to jet, has a dark- 

grayish, black, or brownish-black color, a large 

conchoid al 

fracture, and receives a good polish ; takes fire readily, and 

bums without melting, with a clear yellow flame. On this 

account it has been used as a substitute for candles, and 

hence receives its name. It is very abundant in Scotland, 

and in several parts of Ayrshire ; is wrought into inkstands, 

snuff-boxes, and other similar articles. In England the 

bituminous coal trade is a large traffic ; over one hundred 

thousand people are engaged in Newcastle, in digging. 

The principal coal mines of France are those of St. Etienne, 

Mons, Charleroi, and Liege. Germany has some coal ; but 

Belgium, Norway, Denmark, and Russia seem to be entirely 

destitute of coal beds. Some few beds are found in the 

Apennines, in Italy. In Spain, coal occurs in Andalusia, 

Aragon, Estremadura, Catalonia, Castile, and the Asturias, 

but not in large quantities. The only coal bed in Portugal 

which is worked, is situated in the province of Beira. 

Coal is also abundant in China, Japan, the island of Madagascar, 

Africa, and New Holland. But nowhere are its 

deposits more extensive and numerous than in the United 

States. It occurs extensively throughout the Middle and 

Western States. The great coal formation in the United 

States is one of its principal and most striking geological 

features, and in its influence upon our industrial pursuits, 

it is unquestionably the most important of all. The coal

JET. 355 

measures are distributed over two principal areas, termed 

the gre%t eastern and the great western coal fields, being 

separated from each other by a wide area of older formations. 

The eastern, or Alleghany coal field, may be traced 

from near the northern limit of Pennsylvania to the south- 

west, in a line parallel with the Alleghany chain, quite to 

the central part of the State of Alabama. The anthracite 

basins, which are of comparatively small extent, lie beyond, 

or to the east of the line here traced as the limits of the 

great eastern coal field. 

From its northeasterly margin it is traced along a veiy 

irregular outline, as far as the Alleghany river, in Warren 

county, Pennsylvania, 

and from thence it follows a direction 

nearly parallel to the shore of Lake Erie, to Portage and 

Summit counties, in the State of Ohio. From thence it 

follows a line generally parallel to its eastern margin, though 

gradually converging to its southern extremity, in Alabama. 

Tli is coal field has a length of more than seven hundred 

and fifty miles, and an extreme breadth of one hundred 

and eighty miles. The superficial area has been estimated 

by Richard C. Taylor to be sixty-five thousand square 

miles and when we consider the ; 

aggregate thickness of 

the different beds of coal over this wide extent, the ag- 

gregate amount of fossil fuel appears indeed incomprehensible. 

The great western coal field, or, as it has been usually 

termed, the Illinois coal field, occupies the larger part of 

the State of Illinois, and parts of Indiana and Kentucky. 

It is separated only by a narrow belt of the lower forma- 

tions, along the Mississippi valley, from the coal fields of Iowa 

and Missouri, the extent of which has lately been shown 

to be much greater than had been supposed. Including 

the parts of this field on both sides of the Mississippi river, 

its greatest extent from southeast to northwest, or from


the headwaters of Green river, in Kentucky, to its northern 

limit, on the Desmoines river, in Iowa, is more than five 

hundred miles ; while its greatest breadth across the States 

of Indiana, Illinois, and Missouri, is more than four hun- 

dred miles, and from its northern termination in Iowa to 

its present known limits, on the Osage river, at the south, 

is more than three hundred miles. This western coal field, 

therefore, including the area thus occupied on both sides of 

the Mississippi river, has a much greater superficial extent 

than the eastern coal field, already described. Perhaps 

the entire area may be estimated at one and a half that of 

the Alleghany coal field, or nearly one hundred thousand 

square miles. Still farther to the south, in Arkansas, there 

is a coal field of considerable extent, which has not yet 

been fully explored ; it is probably connected with the 

Missouri field. 

There are coal fields in Michigan, Rhode Island, and 

Massachusetts, Eastern Virginia, North Carolina, near Fort 

Laramie, Puget's Sound, and Bellingham Bay. 

The entire area occupied by coal measures in the United 

States, east of the Rocky Mountains, is about two hundred 

thousand square miles. 

The quantity of bituminous and anthracite coal consumed 

in the United States, may be estimated at fifteen millions 

of tons annually. 

The jet of Whitby, in Scotland, forms part of a thick 

bed of lignite found there in the upper lias marls ; it differs 

in this respect from the jet worked in France and Spain, 

which is found in irregular veins in the lower marls of the 

cretaceous series. 

Cannel coal is chiefly used in the manufacture of gas, 

but some of the harder and more compact kinds are oc- 

casionally cut into various ornamental objects, several of 

which were represented in the London Exhibition ; the most

MEERSCHAUM. 357 

interesting of these, as a finished work, well designed and 

well executed, was a garden seat, from the parrot coal, in 

the Fifeshire coal field, exhibited by His Royal Highness, 

Prince Albert ; also a model of the Durham Monument, 

and a wine-cooler, both of which were wrought from the 

Newcastle coal field. A set of chessmen and a snuff-box, 

both made of cannel coal from China, were exhibited. In 

Roman Catholic countries, a large quantity of small orna- 

ments, such as crosses, beads, rosaries,


cobalt becomes red, and is decomposed by hydrochloric 

acid. 

It is found in nodules, at Kiltschiek, near Conian, in Na- 

tolia, in a large fissure, six feet wide, in calcareous earth ; 

near Thebes, and in many other parts of Greece ; Vallecas, 

near Madrid, and Cavaiias, near Toledo ; Pinheiro, in Por- 

Hrubschitz and Osbowern, in Moravia, and in Swe- 

tugal ; 

den ; but by far the largest quantity is derived from the 

peninsula of Natolia, 

in Asia Minor. It is called meer- 

schaum, or ecume de mer, on account of the belief of the 

workmen engaged in digging the mineral, that it grows 

again in the fissures of the rock, and that it puffs itself up 

like froth. Good meerschaum is tolerably soft ; resists the 

pressure of the hand, but is easily indented by the finger 

nail, and especially after having been wetted ; it may be 

easily cut with a knife. 

Although the fracture is earthy, and rarely conchoidal, 

still the state of aggregation of pure meerschaum is very 

variable, as is proved by the marked difference in the specific 

gravity. Some kinds sink in water, others float on 

its surface ; 

and these qualities are, in the estimation of the 

pipe-maker, indicative of different values, for he rejects 

both the very heavy and the very light, and prefers those 

of medium density. The light varieties are generally very 

porous, and even contain large cavities, whilst the heavier 

kinds are suspected to be an artificial product. Formerly, 

the material was roughly fashioned, on the spot, into bowls, 

which were elegantly carved in Europe. The art was specially 

cultivated at Pesth and Vienna, where it formed an 

extensive and important branch of trade. These rough 

bowls still occur in commerce ; but by far the greater part 

of the meerschaum is exported in the shape of irregular 

blocks, with obtuse angles and edges, requiring careful 

manipulation, with the aid of water, in order to remove

MEERSCHAUM. 359 

irregularities and faulty portions. This preliminary treatment 

still leaves numerous blemishes. The meerschaum of 

commerce has defects of various kinds ; besides various 

minerals scattered through its mass, it contains a hard sort 

of meerschaum, which the manufacturers call chalk, and 

which is the cause of much difficulty in the carving. Pre- 

vious to the mechanical treatment of the meerschaum for 

making the bowl, it is subjected to a certain preparation. 

It is soaked in a liquified unguent, composed of wax, oil, 

and fat ; 

the wax and the fat which the substance absorbs, 

cause the colors which meerschaum assumes after smoking. 

Under the influence of the heat produced by the burning 

tobacco, the wax and fat pass through all the stages of a 

true process of dry distillation ; the substances thus formed 

become associated with the products of the distillation of 

the tobacco, and by their diffusion through the meerschaum, 

all those gradations of color which are so highly prized by 

the connoisseur, are produced. 

Occasionally, though rarely, the bowls are artificially 

stained, by steeping them, before they are soaked in wax, 

in a solution of copperas, either alone or with dragon's 

blood. This process must manifestly very materially affect 

the shade of color produced in smoking. 

The large quantity of meerschaum parings left in roughing 

out the bowls, would entail considerable loss, unless 

some process had been devised of rendering them available. 

A species of meerschaum bowl has long been known in 

commerce, under the name of massa bowls, which is made 

from the parings. They are triturated to a fine powder, 

boiled in water, and moulded into blocks, with or without 

the addition of clay. Each of these blocks suffices for one 

but before they can be used, they must be allowed 

bowl ; 

to dry for some time, as they contract considerably. These 

bowls are distinguished from real meerschaum by their


greater specific gravity ; but there is no very certain test by 

which the real meerschaum can be distinguished from the 

composition, and many suppose that all the heavier descriptions 

are spurious, though there is no absolute proof of 

this being the case. A negative test may, however, be 

mentioned : the composition bowls never exhibit those little 

blemishes which result from the presence of foreign bodies 

in the natural meerschaum ; therefore, if a blemish occur 

in a meerschaum bowl (which is frequently the case), the 

genuineness of the bowl is rendered more probable ; 

but as 

these do not show until after the bowl has been used for 

some time, the test is not of much value. 

Very extensive and valuable collections of meerschaum 

pipes and mouth-pieces were exhibited in the London Crystal 

Palace, from Gotha, of both real and imitation meer- 

schaum bowls. From Turin, Sardinia, were elaboratelycarved 

meerschaum pipe-bowls, the sculpturing of which 

was very exquisite. From Austria a large collection of 

massa pipe-bowls and cigar-tubes, which were manufactured 

from meerschaum dust ; the former of these articles was 

elegant, and the execution so good, that they were with 

difficulty distinguished from the real meerschaum. 

The importation of meerschaum pipes and cigar-tubes 

into the United States has of late become very extensive, 

and it was estimated at two hundred thousand dollars the 

last year. 

LAVA. 

This mineral is a compound of several minerals, and is a 

volcanic production. It occurs massive, with vesicular or 

porous marks ; has a splintery and conchoidal fracture ; a 

lustre dull or glistening ; is opaque, and of gray, brown, 

red, yellow, black, green, and white colors, of all their 

shades. It often contains crystals of felspar, leucite,

JADE. 361 

hornblende, &c. In the arts, for ornamental purposes, the 

compact varieties, only, are cut and polished. 

In Naples, 

jewelry and ornaments in great quantities are manufactured 

and exported ; 

such as pins, ear-rings, intaglios, snuff-boxes,' 

vases, candelabras, &c. The different lavas are cut with 

sand and emery, and polished with pumice-stone. Lava is 

found in all volcanic countries, and particularly at Etna, 

Vesuvius, Hecla, in Mexico, the Lipari Islands,

362 A POPULAR TEEATISE ON. GEMS. 

SERPENTINE. 

This mineral derives its name from its variegated color, 

which resembles the skin of a serpent. It is generally 

divided into two varieties : 

tine ; 

the common, or opaque serpen- 

and the precious, noble, or tmnslucent serpentine. 

Serpentine occurs massive ; the common is occasionally 

crystallized in rhomboidal crystals, 

in Norway, New Jer- 

it has a splintery, uneven, and con- 

sey, and Pennsylvania ; 

choidal fracture ; is unctuous to the touch ; yields to the 

knife ; its colors are green in all its shades, but also reddish 

and grayish ; hardness, 3 '4 ; specific gravity, 2*5 ; is infusi- 

ble before the blowpipe, but with borax dissolves into a 

transparent glass. 

It does not belong to the stratified 

rocks, but to the ophites of Brogniart, and is mostly asso- 

ciated with granite, gneiss ; micaceous, chlorite, argillaceous 

schists, and limestone; it therefore belongs to the primi- 

tive formation. 

Serpentine, for richness and variety of colors, exceeds all 

other rocks ; and it abounds all over the globe, in large 

consolidated masses. The finest precious serpentines come 

from Fahleen and Gulsjo, in Sweden, the Isle of Man, the 

neighborhood of Portsay, in Aberdeenshire, Corsica, Sibe- 

ria, and Saxony. Common serpentine occurs at Lizzard 

Point, in Cornwall. In the Alps we find the serpentine 

nine thousand feet high ; in France, the mountains of Li- 

mousin ; 

in Spain, Norway, Sweden, Scotland, the Shetland 

Isles, England, Italy, Bohemia, Saxony, Bavaria, and Swit- 

zerland; in the United States we find it all along the 

Atlantic coast, where the primary rocks are found, as at 

Hoboken (New Jersey), opposite to New York city, War- 

wick (New Jersey), as far as Maryland, at Bare Hills, 

through Pennsylvania, Rhode Island, Connecticut, Massa- 

chusetts, Vermont, &c. The serpentine beds of Massachu-

SEKPENTTXE. 363 

setts are inexhaustible. In Middlefield, Massachusetts, the 

bed is one quarter of a mile in breadth and six miles in 

length, which alone would be sufficient to supply the whole 

world with a valuable material for ornamental and archi- 

tectural purposes. There are beds at Westfield, Blanford, 

Pelham, Zoar, Windsor, Marlborough, Cavendish, and 

other towns in Vermont. Most beautiful specimens are 

and latterly a new 

found in Newbury, near Newburyport ; 

locality was discovered by Dr. Jackson, in Lynufield, 

Massachusetts. 

Serpentine 

incloses chromate of iron in the Shetland 

Islands, Maryland, &c. ; and is on that account of the 

highest importance to the artist. 

It is easily wrought on lathes into various articles ; such as 

snuff-boxes, vases, inkstands, &c. ; in a small place named 

Zoblitz, in Saxony, several hundred persons are constantly 

employed in the manufacture of boxes, trinkets, and chim- 

ney-pieces. The locality at Granada, in Spain, has supplied 

many churches and palaces of Madrid with large columns, 

and other ornaments. It is* really surprising that the in- 

habitants of those districts where the precious serpentine 

is found, have not yet employed it as an article of trade, as 

the quality of the American serpentine is, if not superior 

to the English and Spanish, certainly not inferior to any 

hitherto found : and I trust that the day is not far distant 

when our parlors will be embellished with mantel-pieces, 

tables, and mantel-ornaments, made of it. Candlesticks, 

mugs, pitchers, knife-handles, fire-iron-stands, jamb-hooks, 

and many other domestic articles, might be formed of it, 

instead of silver-plated, steel, and cast-iron ware. 

Serpentine 

is often associated with a number of other 

minerals : as, , serpentine with talc ; 5, serpentine with 

diallage or schiller-spar ; c, serpentine with amianthus ; d, 

serpentine with asbestos ; e^ serpentine with garnets ; /,


% 

serpentine with actinolite, &G. That variety which contains 

amianthus in a layer, is sometimes exceedingly beautiful ; 

and when polished has the appearance of satin spar. 

MARBLE. 

This is a carbonate of lime, and a wide range of minerals 

belong to this class, containing 

substances which are sub- 

servient to architectural and ornamental purposes ; the 

author intends, therefore, treating this subject more exten- 

than other common 

sively and giving it a wider range 

minerals, and to copy from the jury report of the London 

and New York Exhibitions. 

The primary form of calcareous spar is an obtuse rhom- 

bohedron, with a great many secondary forms; has a 

hardness of 2'5 to 3'5 ; specific gravity, 2'5 to 2*7 ; it has 

a vitreous lustre, also earthy; white or grayish-white 

color usually white, with a great variety of shades 

streak ; 

of gray, red, green, and yellow, also brown and black ; it 

is transparent and opaque, the transparent varieties ex- 

hibit double refraction very distinctly ; fracture usually 

conchoidal, but obtained with difficulty, when the specimen 

is crystalline. It is composed of .lime and carbonic acid, 

the colored varieties often contain, in addition, small portions 

of iron, silica, magnesia, alumina, and bitumen, and 

acids produce a brisk effervescence ; before the blowpipe 

it is infusible, it loses, however, its carbonic acid, gives out 

an intense light, and ultimately is reduced to pure lime, 

or quicklime. 

Calcareous spar appears under a very great variety of 

forms and aspects ; 

been created by mineralogists. 

a great many species have, therefore, 

Iceland spar was first applied to a transparent crystal* 

lized variety from Iceland, where it was found in a cavity

MARBLE. 365 

in trap, with stilbite, on the north shore of Eskifiord, on 

the east coast of Iceland ; and the property of double re- 

fraction was first observed in this variety of carbonate of 

lime. 

Oolite consists of minute spherical particles aggregated 

by calcareous cement, so as to produce a massive structure 

and nearly earthy appearance ; it occurs in extensive beds, 

and is so called from its resemblance to the roe of fish, 

from wov, the egg. 

Pisolite, or pea-stone, differs from oolite in the larger 

size of its particles, which are composed of concentric la- 

mina. 

Chalk is a massive opaque variety, usually white, and 

possessing a purely earthy aspect and absence of lustre, it 

is usually much softer than the other varieties of this 

species, and appears to consist in a great 

aggregation of fossils, chiefly infusorial. 

measure of an 

Tufa, an alluvial deposit from calcareous springs; it 

has a very porous structure. 

Agaric mineral, or rock milk, is a loose friable variety, 

deposited from waters containing carbonate of lime in so- 

lution, it is formed about lakes whose waters are impregnated 

with lime ; also in fissures in limestone, and in lime- 

stone caverns. 

Anthraconite, or stink-stone, swine-stone, which is found 

columnar, granular, and compact, of various shades, emits 

a fetid odor when struck with the hammer. 

Stalactites are pendant masses of limestone, formed in 

limestone caverns by the percolation of Water, holding 

lime in solution, through their rocky roofs ; the evaporation 

of the water causes the deposition of the lime, and thus, in 

time, columns are often formed extending from the roof to 

the floor of a cavern ; the water which drops to the floor 

from the roof also evaporates and causes the formation of a


layer of limestone over the floor ; this variety 

has been 

called stalagmite. 

Argentine possesses a silvery-white lustre and contains a 

little silica. 

Fontainebleau limestone Is an aggregate of secondary 

rhombohedrons, containing, mechanically mingled, large 

portions of sand ; 

this species in some of its forms is very 

generally diffused. 

Marble includes all the imperfectly crystalline and earthy 

varieties which admit of a high polish ; it is also called 

granular limestone, or statuary marble, which forms sometimes 

entire mountains ; but more frequently occurs in beds 

in gneiss, porphyry, and mica slate. The world has been 

supplied for centuries past with statuary marble from the 

Carrara beds on the gulf of Genoa, from the islands of 

Paras, Naxos, and Tenos ; 

Pentillicus and Hymettus, near 

Athens, in Greece, and Schlandens, in Tyrol. 

Calcareous spar is the principal source of our polished 

marbles, the material for sculpture, quicklime, for artificial 

stone, flux for smelting ores, &c. A peculiarly fine-grained 

compact variety is employed in lithography, which is mostly 

imported from Bavaria, under the name of lithographic 

stone.. 

where the manufac- 

Italy is pre-eminently the country 

ture of marble has been found most congenial to the 

artistic feeling of the mass of the people, and there, or in 

its vicinity, at the present day, a large part of the best 

marbles used in central Europe are obtained and worked. 

Of late years, however, France, Spain, Portugal, and parts 

of Germany and Belgium, have employed for their own use 

and in their own style, many useful and valuable marbles 

with which they abound, and in England manufactories 

have arisen, at first and chiefly in Derbyshire, but also in 

Devonshire and Cornwall, in which much has been done to

MARBLE. 367 

raise the character of marble decoration, by employing the 

excellent material which abounds in those places, and by 

introducing various useful objects of house-decoration at a 

price which, though somewhat too High for the mass of 

consumers, is far below that of foreign goods of the same 

kind in that country. Ireland, also, in which several fine 

marbles occur, has given proof of some activity in this 

manufacture, for which, indeed, nature has afforded many 

facilities to carry out to full advantage. 

Many marbles from Greece, Italy, and the coast of Asia 

Minor, were used Jby the ancients, but the quarries are now 

exhausted or concealed by rubbish. Among them may be 

mentioned the true Parian of Greek sculptors, and some 

other fine white marbles the nero ; 

antico, now a very rare 

black marble, considered purer and better than the known 

kinds ; the rosso antico, a deep blood-red marble with veins 

and spots; the verde antico, a green and very beautiful 

porphyritic breccia ; the giallo antico, not unlike the modern 

Sienna marble, of very rich yellow tint, with some others. 

Most of these are only known in sculptured specimens ; but 

many, if not all the colors are closely approximated by 

recent marbles. 

The French marbles, those illustrating the Pyrenees and 

Vosges, were not less interesting. Messrs. Derville exhibited 

one hundred slabs of marble, each sixteen inches in 

height, comprising twenty varieties, and among them the 

marble called " girotte" (spotted with red and brown), and 

the -white marble of St. Beat, all remarkable for the rarity 

of their colors and the beauty of their polish. The Campan 

marbles also possess a peculiar geological interest in the 

number of goniatites which they inclose and which are 

often mixed confusedly with the paste; an arrangement 

which evidences the great change which these limestones 

have undergone at some period, and which proves their


metamorphism, like the limestones of the State of New 

York. 

The chief marble manufacture of England is in a part of 

Derbyshire remarkable for its picturesque beauty, extend- 

ing along the valley of the Derwent and its principal 

tributary, the Wye, from below Buxton to Derby. 

The machinery for sawing and polishing was first estab- 

lished at Derbyshire at the village of Ashford, near Bake- 

well, in the year 1748, water being the motive power; in 

1810, similar machinery was erected in Bakewell, and for 

many years past, also, in Derby. 

The most important marbles of Derbyshire are the black, 

the rosewood, the encrinital, the russet or bird's eye, and a 

mottled dark and light gray kind, occasionally containing 

numerous small corals. Of some of these there are several 

varieties. Others might be added to the list of those 

found in the northern part of the county, one of which 

is a beautiful red, resembling the rosso antico, but it is ob- 

tained only in small blocks or lumps. 

. At Welton, in Staffordshire, near the borders of Derby- 

shire, are marbles differing much from the above, but they 

have not been brought into any considerable use, and are 

generally subject to flaws. The black marble is of very 

fine color and texture, but large slabs free from small veins 

of calcareous spar are rare ; 

the best quality occurs in beds 

of from three to eight inches in thickness, some beds are 

thicker. This marble is, perhaps, superior to the similar 

kinds found in other parts of Europe and is greatly valued 

for inlaying ; it is tough and contains a good deal of carbon, 

which imparts the color. 

Black marble is extensively used for ornamental objects, 

such as vases, pedestals, chimney-pieces, &c., for which it 

is admirably adapted. 

Rosewood marble is extremely hard and of close texture ;

MARBLE. 369 

the beds are of considerable thickness, but the most beau- 

the 

tiful part of the ma'rble ia only about six inches thick ; 

name is derived from the marking of the marble being 

somewhat similar to that of rosewood. 

Encrinital marble is the one in most extensive use, and 

contains very numerous fossils, consisting almost exclusively 

of the broken fragments of encrinital stems, often entangled 

in coral ; it may be obtained in blocks of large superfices 

and of a thickness of two to two and a half feet. 

Russet, or bird's eye, takes its name from its color and 

the shades varying from light-gray to brown. 

appearance ; 

It contains numerous minute fossils, also encrinital, and is 

found in beds from six to eighteen inches in thickness. 

Dark and light mottled gray marble, called Newburgh 

marble, and the overlying bed, which is coralline, can be 

obtained from one to two feet thick. 

The manufacture of Devonshire marble is much more 

modern, and the material is generally less manageable. 

Almost all the beautiful marbles of that county, especially 

those near Plymouth, are fossiliferous, brittle, and very apt 

to contain veins and cracks. The marbles of Devonshire 

belong to an older geological period than those of Derbyshire, 

the latter being exclusively of the carboniferous 

limestone series, underlying the coal measures and mill- 

stone grit ; 

while the former are of the devonian or middle 

paleozoic epoch. 

Among the most notable marbles in the London Exhibi- 

tion, may be mentioned the following articles:: 

Three chimney-pieces of Carrara marble, with many 

sculptured figures, from Milan, in Italy ^ columns and 

pedestals of the madrepore marble, from a quarry in Devon- 

shire ; some pedestals of green marble, from Connemara, 

in Ireland ; a table belonging to the East India Company 

was exhibited, the top of which consists of a slice of a


column from Nineveh; 

several slabs of the Lumachella 

marble, and a marble called verde di prato, were exhibited 

from Tuscany, which were extremely beautiful. A bust of 

Grattan, of Irish marble of a beautiful yellow color, attracted 

much attention. 

It may not be out of place to mention here the extensive 

display of marble statuary, which was also at the London 

Exhibition, only a few will be enumerated for want of 

space : 

1. Marble statue representing Gratitude. 

2. Group representing Eve with Cain and Abel asleep in 

her arms. 

3. Marble statue of Susannah. 

4. Iconic. statue in marble. 

5. Marble statue of Eve after the Fall. ^ . 

6. Marble statue representing the Greek Slave. 

7. Marble group representing Cephalus and Procris. 

8. Marble figure representing a Boy frightened by a 

Lizard. 

9. Reclining figure, in marble, representing Ishmael. 

10. Marble statue of a Boy catching a Butterfly; also, 

a marble figure representing Arethusa. 

11. Marble statue representing Giotto. 

12. Marble statue of the sculptor Flaxman, and two 

statues of the first Lord Eldon, and his brother, Lord 

Stowell. 

13. Marble group of a Girl with a Lamb, representing 

Innocence. 

14. Marble statue representing a Startled Nymph. 

15. Marble figure of a Bacchante. 

16. Marble statue of Dying Gladiator. 

17. Marble group representing an episode in the history 

of the war between the Amazons and the Argonauts. 

18. Marble statue of Psyche. %

MAKBLE. 371 

19. Marble statue representing a Girl carrying a Nest of 

Cupids. 

20. Marble statue representing Eurydice. 

21. Marble group, "The Orphans." 

22. A reclining marble figure of Bacchus. 

23. Model in marble of a Friar presenting the Crucifix 

to two Children. 

24. Marble bust of the poet, Vincenzo Monti. 

25. Figure in marble representing Mary Magdalen. 

26. Marble group, Sleeping Child and Dog. 

Italian marble furnished the material from which most 

of the above sculptures were wrought. 

The United States limestones, for building purposes, and 

marble for statuary, are found in great abundance, and 

many of them fairly compare with the Italian and English 

marbles. The white granular limestones are mined in many 

places ; they all belong to the newer metamorphic rocks, 

where they occupy a wide range, from Vermont, Massa- 

chusetts, Rhode Island, Connecticut, New York, Pennsyl- 

vania, and Maryland, to Missouri ; but the best statuary 

marble has as yet only been found in the eastern part 

of Vermont: 100,000 cubic feet of good marble, suitable 

for building stone, mantel-pieces,


ries in Massachusetts are at West Stockbridge, Egremont 

Groat Harrington, Lanesborough, New Ashford, Sheffield, 

and New Marlborongh. In New York, marble is quarried 

in large quantities at Hastings and Sing Sing, and Dover, 

in Dutchess county, and the range of granular limestones 

extends through Columbia, Dutchess, and Putnam coun- 

ties ; 

and in Connecticut the same granular limestones occur 

in abundance; also in New Jersey, a few miles west of 

Philadelphia, and near Ilagerstown, in Maryland. The 

marble quarries in Rhode Island, Eastern Massachusetts, 

and Maine, furnish very fine marble, belonging to the 

metamorphic limestones of a more recent date, but it is not 

as durable as those of an older age ; 

has more fissures. 

it is more friable, and 

Bird's-eye or encrinitaJ marble forms an extensive bed in 

the State of New York; it is a compact crinoidal limestone, 

containing fragments of stems and joints of crinoids 

of a bright pink, and other organic remains of a dark 

color, which, on the gray ground, give a beautiful variety. 

A similar limestone, susceptible of receiving a polish, occurs 

in the lower bed of the Niagara limestone, at Lockport and 

at Becraft's Mountain, near Hudson, where the organic 

remains are nearly similar to the first. Also the Onondaga 

limestone affords a similar marble, and taking a fine polish, 

with a much greater variety of organic remains than either 

pf those just described. All these limestones compose very 

thick beds, and are all suitable for ornamental purposes; 

they are a very excellent and durable building-stone, and 

are extensively used for the massive and beautiful locks and 

piers on the Erie canal, at Lockport, and as building-stone 

in Buffalo, Lockport, and Rochester, and the city hall and 

court house in Chicago have been built from it ; they belong 

to the group of limestones called the Niagara group. 

On a recent visit to Buffalo, the author's special attention

MA-KBLE. 373 

was directed to the wide range of marble, beginning at 

Harlem Bridge, New York island, where the fine white 

granular marble begins ; crossing thence to Hastings, twen- 

ty miles farther up the Hudson river, of a still finer, and 

also coarser white marble ; 

white marble ; 

farther on, the Dutchess county 

and gradually coming into the black marble 

region at Schenectady. At Little Falls, high cliffs of 

that species of limestone, with magnificent scenery, excited 

his admiration on passing in the railroad cars. A 

short visit to the State Cabinet of Geology in Albany 

gratified him in the extreme ; 

and every person desirous of 

being informed of the vast resources of limestone of the 

State of New York, cannot spend a more pleasant or instructive 

day than to examine the well-arranged museum 

of the geological formation of the State of NewT York, and 

of the minerals of this State and neighborhood. 

A short description of this class of limestones may give 

the reader some idea of the intrinsic value of the results of 

the scientific -research, accomplished through the liberally 

extended munificence of the several legislatures of the 

State, by such men as Hall, Eramons, Conrad, Mather, and 

Yannuxem. The visitor will perceive, on the entrance 

into the large hall of the Geological Cabinet, a large slab 

of the chalky limestone, with the thousand ammonites and 

orthoceratites imbedded ;. he next beholds "the bird's-eye 

limestone, some specimens having also thousands of sharks' 

teeth on the surface ; he next sees the Black river and 

Trenton limestone, both rough, and also fine polished specimens, 

inclosing the orthoceratite in its polished state, as 

if cut in two parts, and it makes a very beautiful appearance 

; the Mohawk valley and Hudson river group, with 

all the imbedded fossils, next attracts his attention ; the 

Utica slate and its large trilobites, from one to twelve 

inches in length, along with the Niagara limestone group,


displaying likewise the gigantic trilobite family, is not less 

attractive than the enormous slab of the black limestone, 

called the corniferous limestone, with the Marcellus shale, 

near Manlius, in Onondaga county. This slab contains 

several ammonites of one foot in length; it is called now 

the 

' 

ffoniatilis expansus 

orthoceratas marcellinius. This 

specimen must weigh at least one hundred pounds, and is 

three feet in length ; and it is certainly a very magnificent 

specimen. 

The large rhombic limestone, from St. Lawrence county, 

with the dogtooth spar, from Lockport, form interesting 

specimens in the Cabinet. 

mineralogical- department of the State 

The splendid quartz crystals, from Herkimer county and 

Lake George, as also the fluor spar of Jefferson county, and 

the beautiful green crystals of apatite, from St. Lawrence 

county, with the sulphate of strontia specimens, from the 

latter, Onondaga, and Schoharie counties, all claim their 

respective merits ; 

the labrador spar and hypersthene, from 

Essex county, the gypsum, sulphate of baryta, the beauti- 

ful rose quartz, from Fort Henry, the red sapphire crystals, 

from Orange county, and the amethysts, intermixed in 

layers with the serpentine, from Putnam county, form very 

fine ornamental minerals. 

Among the most interesting minerals of this State may 

be mentioned the rensselaerite, from Fort Edward ; 

a great 

many specimens of this interesting mineral, both rough 

and polished, may be seen in the State Cabinet. It forms 

irregular masses in that limestone region, has an unctuous 

feel of stalactite, but is of superior hardness ; resembles more 

the satin spar in its crystalline form ; 

it resembles pyroxene, 

but differs much from it in its hardness and specific grav- 

ity ; its hardne'ss is 3'5 to 4', and specific gravity 2'87 ; its 

color is white, yellowish-white ; has uneven fracture. This

MARBLE. 375 

mineral was -named in honor of the late patroon, Gen, 

Stephen Van Rensselaer, of Albany. This mineral abounds 

in St. Lawrence county, and will, no doubt, at no distant 

day, be wrought into many beautiful ornaments ; the polished 

specimens in the State Cabinet are very fine. 

The Potomac and breccia marble is a rock of the newer 

red sandstone series ; it forms a beautiful rock, and the columns 

of the hall of the House of Representatives, at Wash- 

ington, are cut from this somewhat hard material. 

The serpentine marble, or verd-antique, occurs in numerous 

localities along the belt of formations which extends 

from northern Vermont, through the western part of 

Massachusetts, Connecticut, a small portion of southern 

New York, New Jersey,- Pennsylvania, and Maryland ; 

this formation is metamorphic of a part of the Hudson 

river group. A very beautiful verd-antique marble occurs 

at Cavendish, Lowell, and Troy, in Vermont ; 

in Cheshire, 

Massachusetts, and in Milford, Connecticut. There are 

two kinds of verd-antique marble the true verd-antique, 

and the serpentine marble; the first occurs in Vermont 

and Milford, Connecticut, and the latter, called the com- 

mon, near New Haven, Connecticut. 

The white coarse-grained marble, from Texas, Baltimore 

and used 

county, Maryland, is quarried very extensively, 

in Washington City for the capitol extension, treasury, and 

post-office department. 

In Missouri occur large beds of white and reddish-white 

marble, in Jefferson county and near St. Louis ; 

the Gene- 

vieve marble, which is an oolitic limestone, has a very 

extensive formation, and is used in St. Louis and New 

Orleans as building-stone ; some marble quarries are full 

of organic remains, and some are so hard and durable that 

they are used for hearths, having extraordinary power to 

resist the action of heat.


Breccia Marble, of Lancaster county, Pennsylvania. 

This is a recent discovery of a variegated marble, a pure 

carbonate of lime, and differs materially from other mar- 

bles of the United States and foreign countries ; and an 

independent name has been given to it by its discoverer, 

viz. : the leocadia breccia, which forms a solid, unstratified 

bed of compact marble. It is admirably adapted for orna- 

menting churches, banks, hotels, and other public buildings, 

as also for private houses for mantels, tables, wainscoting, 

balustrades, &c. It is very easily wrought, and has, therefore, 

the advantage of many other marbles of the United 

States. This new locality bids fair to drive the foreign and 

more costly marbles out of the market ; 

as for brilliancy of 

color and its variegated character, and for strength and 

durability, it has not its equal, either in the United States 

or any foreign country. It is sincerely to be hoped that 

so valuable a bed of limestone may not be left slumbering 

for another century, but that the discoverer, Mr. James -W. 

Hale, may reap the benefit of its speedy development and 

general application. 

The New York Exhibition of 1853 was well supplied 

with statuary from the whole world, but -particularly from 

Italy. The Italian works consisted mostly of copies from 

the antique. The copy of the Flora of the Capitol; Barto- 

lini's Faith ; Harpocrates, and Cupid in a mischievous niQod ; 

Canova's Hebe, and Thorwaldsen's statuary, were all of 

great merit. Power's statues of Eve and Proserpine have 

been, in addition to the Greek Slave and Fisher-boy, 

already noticed among the great curiosities of the London 

Exhibition. We will enumerate the other statues in marble 

which were much admired at the New York Exhibition, 

viz. : 

1. A Bacchante, and Psyche, from the sculptor, Gait, of 

Norfolk, Va.

MARBLE. 377 

2. Bust of Daniel Webster ; the Husbandman's Orphan, 

a nude figure of a boy leaning on a spade ; 

ing Child, 

all in marble, by Pietti, New York. 

3. The Minstrel's Curse, by Miller, New York. 

and the Sleep- 

4. Christ in the Sepulchre, by Creswell, Brooklyn. 

5. Bust of Dr. John Green, of South Carolina, and one 

of Charles Allen, of Massachusetts, by Kinney, of Worces- 

ter, Massachusetts. 

6. Head of a Female, by Ives, Connecticut. 

7. Bust of Daniel Webster, by King, Boston. 

8. A veiled Cupid, by Moon, New York. 

9. Head of Jupiter, and statuettes, by*Ferris & Taber, 

New York. 

10. Cupid, and Charity, a female figure seated, with an 

infant in her arms, life size, by Baudel, London. 

11. Busts of Daniel O'Connell and Father Mathew, from 

Hagan, Dublin. 

12. Bust of Jenny Lind, by Durham, London. 

13. Bust of Palmerston, by Sharp, London. 

14. Ruth and Naomi, by Kirk, Dublin. 

15. Bust of Louis Napoleon, emperor of France, by 

Deumier, Paris. 

16. Statue of Racine, by D'Angier, Paris. 

17. Lesbia, by L'Eveque, Paris. 

18. Damalis, by Etex, Paris. 

19. A veiled head ; a sleeping Cupid ; Psyche reposing, 

and bust of Prayer, by De Bokeleer, Antwerp. 

20. Statue of Venus and Cupid, by Fraikin; Brussels. 

sels. 

21. Two Children Sleeping, as a group, by Geess, Brus- 

22. Hebe, from Canova, by Lazzerini, Rome. 

23. A Danaide, head of an Amazon, and bust of Queefl 

Victoria, by Bariata, Rome. 

24. Iris, by Cartei, Florence.


ence. 

25. Hagar and Ishmael in the Desert, by 'Catelli, Flor- 

26. Lord Palmerston, by Fabrucci, Florence. 

27. Harpocrates, the God of Silence, full length ; and 

Cupid in a mischievous mood, by Santarelli, Florence. 

28. Statue of Truth, a tipsy Bacchus, and Virgin of the 

of the Eucharist, a bas-relief; by Cambi, Florence. 

29. The Betrothed, and the Son of William Tell, by 

Romanelli, Florence. 

30. The Genius of Sacred Music, and Laura, by Consani, 

Florence. 

31. The Sleep of Innocence, by Dupri, Florence. 

32. John the Baptist sleeping, by Magi, Florence. 

33. Death of Ferruccio, by Giampaoli, Lucca. 

34. Rebecca, Faithful Love, the Child's First Grief, bust 

of Cleopatra, and bust of Heloise, by Vaspi, Florence. 

35. The Mendicant, by Strazza, Rome. 

36. Shepherdess and Bird, the Guardian Angel, and 

Psyche sorrowing, by Bimaimi, Rome. 

37. Cupid leaning on a wine-skin, by Strechi, Rome. 

38. Cupid with the arms of Mars, the Sacrifice of a God, 

and three Female Dancers, by- Jerichau, Rome. 

39. Columbus, Staffetti, Carrara. 

40. A Bacchante, a nymph wreathing herself with flow- 

ers, the Genius of Summer, the Genius of Spring, Herminia 

writing the name of Tancred, and Poetry, by Pelliccia, 

Carrara. 

41. Cupid, Psyche, and Venus of the Louvre, by Fabri- 

cotti, Carrara. 

42. The Flora of the Capitol, Bartolini's Faith, the 

Dying Gladiator, bust of the Saviour, St. John the Baptist, 

bust of Rousseau, by Baratta, Carrara. 

43. Pope Pius IX., by Tenerasie, Carrara. 

44. Bust of Washington, by Bagazzi, Carrara.

MAKBLE. 379 

45. Cop/of the Warwick Vase, Flora of the Capitol, the 

Pet Bird, Apollo Belvidere, Copernicus, 

Diana of the 

Louvre, Dante, Jupiter, Shakspeare, Madonna, and Faith, 

by Marchetti, Carrara. 

46. Marcus Tullius Cicero, and Paris, by Fontana, Car- 

rara. 

47. The Shepherdess and Lamb; a Struggle 

Heart, by Orlandi, Carrara. 

for the 

48. Ceres, Venus, Child with a Bird, Psyche, Poetry, 

and Vincenzo Gioberti, by Bruneri, Turin. 

49. The Virgin mourning over the dead body of Christ, 

by Angero, Turin. 

50. The Virgin and Angel of Annunciation, by Galeazzi, 

Turin. 

5 1 . Hebe offering Nectar to the Eagle, by Kachszman, 

Milan. 

52. Boy riding on a Crawfish, a Tortoise, Leda with the 

Swan, Innocence, and veiled head, by Croff, Milan. 

53. Atala and Chactas, colossal bust of the Redeemer, 

by Fraccardi, Milan. 

54. Infant Saviour, Child on the Waves, by Galei, Milan. 

55. The Deserted, veiled head, Cupid forcing the Roses, 

nest of Cupids, cage of Cupids, and basket of Cupids, by 

Motelli, Milan. 

56. Sleeping Venus, by Rados, Milan. 

57. Resignation, by Tandardini, Milan. 

58. The Fisher-boy, by Cacchi, Milan. 

59. The Soldier's Son, by Jorini, Milan. 

60. Head of the Saviour, and colossal bust of Vincenzo 

Monti, by Langiorgio, Milan. 

61. Virgin grieving, by Nezeo, Milan. 

62. Eve after the Fall, by Ragani, Milan. 

And many more, less notable. All of these sculptures 

were in Italian marble.


Sfttlactite and Stalagmite. 

It occurs in large tuberous, undulated masses, botryoidal. 

mammillary, or concretional, either in icicles or circles ; 

has a fibrous fracture ; is translucent ; of a pearly lustre ; 

color generally yellowish-white and white ; its composition 

is calcareous spar ; 

it originates in caverns, through which 

water, holding this in solution, filters, and on its ultimate 

evaporation leaves the carbonate of lime in various forms, 

which sometimes resemble altars, pillars, animals, &c. 

Those pillars or icicles which are pendant from the roof, 

and those rising from the base, are sometimes divided into 

stalactite for the former, stalagmite for the latter. But the 

cause of their existence is the same, and there ought not 

to be any distinction in their name. 

Ornaments of stalactite in the shape of vases, &c., are 

often seen in fancy stores. The greatest localities of this 

mineral are, the Grotto of Antiparos, and Bauman's Cave, 

in the Hartz, which I visited in 1827, and which displays 

gigantic stalactites; also in Derbyshire. In the United 

States, are very celebrated caves which yield this article. 

These have been described by my friend, Charles Cramer, 

Esq., late Russian Vice Consul at New York, now 

of the Isle of Wight, an enthusiastic mineralogist, of St. 

Petersburg, in a pamphlet published by the Imperial 

Mineralogical Society of St. Petersburg, in the German 

and as this interesting little work is not accessi- 

language ; 

ble to all, I will here translate the list of all the caves enu- 

merate'd by him as North American. We would observe 

that these are not all situated in limestone regions, neither 

do they all furnish stalactites. 

Canada. Grotto in the Niagara ; a cave in Lanark, 

Upper Canada ; 

a smaller cave at the same place. 

New Hampshire. The Devil's cave. 

'

Vermont. Caves in Bennington ; caves in Dorset. 

381 

Massachusetts. Natural bridge and cave at Nahant ; 

natural bridge over the Hudsop brook ; 

cave near Sunder- 

land ; cave in Berkshire ; two caves near New Marlbo- 

rough ; cave near West Stockbridge ; cave in Lanesboro ; 

cave in Adams ; Purgatory, near Sutton. 

Connecticut. West Rock cave, New Haven. 

Rhode Island. Purgatory, near Newport ; Spouting 

cave, near Newport. -'4*; 

New York. Cave near Watertown ; cave at Niagara ; 

Ball's cave Knox's cave ; ; Monito, at Wigwam, or Devil's 

Abode ; Esopus cave. 

Pennsylvania'. Devil's Hole, in Bucks county ; cave on 

the Swatera river. 

Maryland. Hughes' cave ; cave at Harwell. 

Virginia. Weyer's cave ; Wreast's cave ; Madison's 

cave ; Zane's cave ; Blowing cave, near Panther Dale ; 

Greenbriar's cave ; cave on the Kanhawa river ; Chapin's 

cave ; Johnson's cave ; Allen's cave ; Ruffner's cave ; Roger's 

cave ; Reid's cave ; Natural Tunnel in Scott county ; Natu- 

ral Bridge in Rockbridge county. 

Ohio. Mason's, cave ; Nature's Building, or Cave in the 

Rock. 

Indiana. Epsom Salt cave ; cave near Corydon. 

Kentucky. Boone's cave ; Russell's cave ; White cave ; 

Mammoth cave ; cave on Crooked creek. 

Tennessee. Big-bone cave ; Arched cave. 

South Carolina. Great Flat Rock cave ; Lover's Leap. 

Georgia. Nicojack cave. 

Missouri. Ashley's cave. 

Mississippi. Abode of the Great Spirit on the North 

West Coast ; cave on Copper river. 

Mexico. Dantoe cave; Chamacasapa cave; San Felipe 

cave. 

'


Cuba. Cave near Matanzas. 

Hayti. Cave near St. Domingo. 

Peru. Cave in the Andes. 

New Andalusia. Canipe cave. 

Mr. Cramer mentions the size of the stalagmites in the 

antechamber of Weyer's cave, as being twelve feet high ; 

those in Solomon's Temple, of the same, twenty-five feet 

high, which are nearly transparent; and its Hermit's Chandelier, 

four feet high, and twelve feet in circumference; the 

colossal stalagmite in Washington Hall, which is said to 

represent the Father of his Country wrapped in his cloak ; 

Pompey's column, thirty feet high ; 

thirty feet in circumference. 

Egyptian Marble. 

also Babylon's Tower, 

This is generally milk-white, or grayish-white and bluish, 

and also black and red, which is called the rosso antico; it 

is of a close granular structure, and was a great favorite 

with the ancient architects. 

Italian Marbles. 

"With these may be counted the Parian marble ; the Pen- 

telian marble ; the Venetian or Lombardy marble, which 

is quite translucent ; the Luni and Carrara marble ; and the 

Laconian marble, or verd-antique. They have all yielded 

materials for the most ancient Greek and Italian sculptors. 

The Venus de Medici, the Diana Hunting, and Venus leaving 

the Bath, are of Parian marble ; a Bacchus in repose, a 

Jason, a Paris, and many Grecian monuments, are from 

Pentelian marble, which comes from the vicinity of 

Athens.

MAEBLE. 383 

American Marble. 

(Additional from the former edition of this treatise.) 

The varieties of marble, which substance is inexhaustible 

in the United States, are very numerous ; 

and I am proud 

to assert,' that for architectural and ornamental purposes, 

they will successfully compete with those of any foreign 

country. The colors are various, from the snow-white to 

the black with gold and grass-green veins. A small dis- 

trict in New England, of about fifty miles in extent, con- 

centrates, I may say, the marbles which may 

be collected 

in Europe through a space of two thousand square miles ; 

for we find in the county of Berkshire, and that of New 

Haven, the representatives of marbles from Italy and Ire- 

and the discoveries which are constantly being made 

land ; 

of additional marble localities are a source of great satisfaction. 

Thirty years ago, the City Hall, of New York 

city, was built of marble from West Stockbridge, Massa- 

chusetts, which was transported at great expense, a distance 

of over four hundred miles ; whereas, afterwards, the 

same quality of marble was discovered on New York island, 

but a few miles distant. According to Professor Dewey, 

the county of Berkshire alone turned out forty thousand 

dollars' worth of marble several years ago. I will here 

enumerate a few of the most interesting marbles: 

a. The Philadelphia marble, which is snow or grayish 

white, and sometimes variegated with blue veins, w r hich 

takes a very high polish. 

Z>. The Potomac marble, which is properly called a 

breccia, being composed of rounded and angular fragments 

from the size of a pea to that of an ostrich's egg. 

Its colors are red, white, gray, and blackish-brown, intermixed 

; it takes a very fine polish, and forms a most beau- 

tiful ornamental stone. It comes from the banks of the


Potomac, in Maryland. As specimens of this, we would 

refer to the .columns in the House of Representatives at 

Washington, which are twenty feet high, and two feet in 

diameter. 

c. The Yerd- Antique, of New Haven, Connecticut. This 

marble is intermixed with serpentine veins, and makes a 

most beautiful appearance. There are inexhaustible quar- 

ries of it at New Haven and Milford ; it bids fair to rival 

every other ornamental stone in the world. Four chimney- 

pieces of this mineral were purchased for the Capitol at 

Washington; and I lately examined a splendid centre 

table, wholly cut from this marble, that was exhibited at 

the tenth annual fair of the American Institute. It is to 

be hoped that some company may undertake to introduce 

this marble more extensively into notice, for it does not yet 

appear to be sufficiently known among our wealthy citizens: 

the enterprise would be well rewarded. Large slabs 

may be seen at the New York Lyceum of Natural History, 

and in the cabinet of Yale College, New Haven. I possess a 

very fine, large slab, polished. Portsmouth, Vermont, likewise 

furnishes splendid verd-antique, specimens of which 

may be seen at the American Institute, in New York. 

d. Berkshire county, in Massachusetts, may justly be 

called the marble pillar of the United States ; and, as Pro- 

fessor Hitchcock remarks, the inhabitants of that county 

cannot but regard their inexhaustible deposits of marble 

as a rich treasure to themselves, and an invaluable legacy 

to their posterity. The towns, West Stockbridge, Lanes- 

borough, New Ashford, Sheffield, New Marlborough, and 

Adams, in that county, keep thousands of hands constantly 

working in their quarries. In 1827, two thousand seven 

hundred tons of marble were exported from that town ; and 

in 1828, a block of from fifty to sixty feet square, and eight 

thick, was raised by one charge of gunpowder.

e. White, fine, granular marble, bearing 

semblahce to the celebrated Carrara marble, 

385 

the closest re- 

is' obtained 

from Smithfield, Rhode Island ; Stoneham, Massachusetts, 

and near Hastings, on the Hudson river. 

Shell Marble. 

This mineral is a secondary marble, and is called also 

conchitic marble, on account of its containing petrified 

shells, which, when polished, conimunicate to their matrix, 

the marble, a most beautifully variegated appearance. 

a. The Lumachella marble is a kind which is very scarce; 

it has a gray or brown ground, interspersed with shells of 

a circular form and golden color, and when held towards 

the reflection of light, displays red, blue, and green tints, 

like those of the precious opal or iridescent labrador.' 

It is sometimes seen in the form of pins and other jewelry, 

but stands,, on account of its scarcity, very high in price ; 

the only locality is in Carinthia ; . one formerly in Devon- 

shire, England, being exhausted. Some splendid specimens 

from Carinthia, are in the collection of Baron de Lederer, 

Austrian consul for this city ; and a very fine specimen of 

the lumachella, at the Boston Society of Natural History, 

was marked with the locality of Neufchatel. 

b. Panno di morto, or funeral pall, is a deep black 

marble, with white shells, like snails; it is only seen at 

Rome, and is very scarce. 

c. Bristol marble, from England, is a black marble, inter- 

spersed with white shells. 

d. Italian shell marbles from Florence, Lucca, and Pisa, 

are red, containing white shells (ammonites). 

e. French shell marbles are very numerous ; those from 

Narbonne are black with white belemnites ; that from 

Caen is a brown marble with madreporites j and those from 

17

386 A POPULAR .TREATISE ON GEMS. 

Languedoc are of a fiery red color, mixed with white and 

of this Napoleon's eight columns for 

gray univalve shells ; 

his triumphal arch in the CarouselJ at Paris, were cut. 

f. The United States "have a great many shell-marble 

quarries ; but they are all black and gray. Those of Trenton 

Falls, Little Falls ; near Seneca lake ; Northumber- 

land county, Pennsylvania; Bernardston, Massachusetts, 

and Hudson, New York, contain either trilobitea or encri- 

nites ; some take a very fine polish. 

PISOLITE AND OOLITE. 

These minerals are likewise composed of carbonate of 

lime; they occur massive, and in distinct concretional 

layers, either in the form of peas or other round grains or 

pebbles, and are of white, yellowish-white, brownish, or 

reddish color ; when cut and polished, they make a fine 

ornamental stone, and present a very effective appearance. 

The former is found in alluvial deposits of the hot water 

mineral springs of Carlsbad, in Bohemia, and the baths of 

St. Philip, in Tuscany ; 

the latter forms large beds in Eng- 

land and France. The city of Bath, in England, is mostly 

built of this limestone. 

ROCK OF GIBRALTAR. 

This is likewise a carbonate of lime ; occurs massive, 

mostly striped ; is yellowish-white, yellow, and brownish ; 

is only found in that rock from whence it takes its name, 

and has been heretofore a great favorite for jewelry and 

other ornaments. At this day we see in shops and private 

houses, pins, brooches, ear-rings, seals, cane-heads, snuff- 

boxes, letter-holders, vases, urns, candelabras, obelisks, &c. 3 

formed of it. It takes a high polish.

APATITE. 387 

APATITE. 

This mineral was named by Werner, on account of its 

color being so deceptive (anaraa), to deceive), as it resembles 

the color of some -other precious stones ; it occurs in six- 

sided prisms, massive and globular ; 

has a conchoidal frac- 

ture ; a vitreous lustre ; color usually sea-green, bluish-green, 

or violet-blue, sometimes white, occasionally yellow, gray, 

and red ; is transparent and opaque ; it resembles the beryl 

and emerald, but is distinguishable by color and hardness ; 

hardness, 4'5 to 5 ; specific gravity, 

3 to 3'235. A bluish 

opalescence is observed in the direction of the vertical axis 

in some specimens, especially in the white variety; fracture 

conchoidal and uneven ; brittle. Some varieties are phos- 

phorescent when heated, others become electric by friction. 

It is infusible alone before the blowpipe, except at the 

edges; dissolves slowly in nitric acid, and without effervescence. 

Apatite usually occurs in primitive rocks ; 

is often found 

in veins of primitive limestone traversing granite, it also 

occurs in serpentine and in ancient volcanic rocks. 

It contains about ninety per cent, subsesquiphosphate of 

lime, and the rest is chloride and fluoride of calcium. On 

account of its phosphoric acid, the compact varieties of 

apatite have become an important article of trade for agri- 

cultural purposes. 

The principal localities are in Saxony, at Ehrenfriders- 

dorff, in the Hartz mountains, where the author collected, 

in his youthful years, some magnificent crystals; also in 

Bohemia, at Schlackenwald ; 

in Cumberland arid Devon- 

shire, England; at t. Gothard, in Switzerland; 

and a 

greenish-blue variety, called moroxite, is found in Norway, 

at Arendal. 

Asparagus stone, which is of a yellow color and trans-


lucent, is found at Estremadura, in Spain, of which many 

fine specimens may be seen at the Academy of Natural 

Sciences of Philadelphia, in Maclure's collection ; also in 

Zillerthal, Tyrol, where it is imbedded in talc. The phosphorite, 

or massive varieties, from Spain and Bohemia, has 

been found in large beds. In the United States it occurs 

in a vein of limestone intersecting the granite at Gouver- 

neur, St. Lawrence county, New York, and crystals of 

ten to twelve inches long and one and a half to two inches 

in diameter, of fine sea-green color, were formerly found 

in abundance. 

Yale College has some fine specimens of this crystallized 

variety, from Baron Lederer's cabinet. Professor Shep- 

herd, Mr. Francis Algar, and Dr. Charles T. Jackson, in 

Boston, possess many fine and large crystals. Mr. Kranz, 

in Bonn, was fortunate to procure, through his collector, 

some gigantic crystals of this beautiful mineral. There are 

some other localities of the crystallized variety in the 

United States, such as Amity, New York, where it occurs 

of a green color in white limestone, presenting the primary 

form, and accompanied with pyroxene and scapolite. Crystallized 

and massive specimens of a bluish-green color 

occur at Boston, Massachusetts, associated with sphene and 

petalite. Reddish-brown crystals,- of one inch in length, 

have been obtained from a granite vein in Greenfield, New 

York. The massive variety of phosphate of lime from 

Crown Point, New York, has furnished several thousand 

tons for export to England as a fertilizing agent, and the 

concretional variety of phosphate of lime from Dover and 

Franklin, in New Jersey, has likewise yielded considerable 

quantities for a manure. These two latter varieties have 

been treated with sulphuric acid (oil oT vitriol), 

in order to 

obtain a superphosphate of lime, which is now considered 

the most useful vehicle to enrich the soil, and to produce

MICA. 389 

the most prolific crops. Liebig and Johnstone, the two 

great agricultural chemists, have demonstrated beyond any 

controversy that .the resuscitation of worn-out soils depends 

materially upon the addition of phosphate of lime ; and 

hence the application of bone-dust, which is a phosphate of 

lime, and guano, which contains the latter ingredient with 

the ammoniacal salts in combination, of which at the 

present day 100,000 tons are annually consumed by the 

farmer, along with the artificially prepared superphosphate 

of lime, are well known, but do not belong here. 

LEPIDOLITE. 

This mineral derives its name from the Greek language, 

from its scaly structure ; it occurs massive, presenting an 

aggregate of minute, shining, flexible scales or hexagonal 

plates ; it has a splintery fracture ; a glistening and pearly 

lustre; is translucent on the edges; its colors are lilac, 

rose-red, pearl-gray, greenish-yellow, and blue ; 

it is 

scratched by glass, and yields to the knife ; has a specific 

gravity of 2'81 ; is fusible with ease into a transparent 

globule. It is found in granite and primitive lime, in 

Monrovia, France, island of Elba, Corsica, Sweden, and in 

the United States, in Maine, New Hampshire, Vermont, 

and Massachusetts. It is cut in Europe for various orna- 

ments, such as plates, vases, snuif-boxes, &c., and will, 'I 

trust, at some future day, be more extensively 

jewelry ; for there are some variegated specimens 

used in 

of a 

peach-blossom color, and very fine granular structure, 

which are extremely beautiful. 

MICA. 

This mineral occurs crystallized, in six-sided tables and 

oblique rhombic prisms, and massive ; also, disseminated ;


it has a perfectly foliated structure ; a glittering and 

metallic lustre ; is transparent and translucent ; very fusi- 

ble and elastic ; its colors are white, green, black, brown, 

peach-red, yellowish, and bluish ;. it has a specific gravity 

of 2'7. It is found in primitive rocks, and forms an ingredient 

in granite, gneiss, mica slate, and other rocks, where 

it more or less predominates ; its localities are, therefore, 

universal, but in Siberia it forms large beds, and is quarried 

for special purposes, such as a substitute for glass windows ; 

and although the United States afford ample localities of 

here for 

it, yet a few years ago quantities were imported 

the doors of Nott's stoves. 

The plumose mica is a beautiful variety, and derives its 

name from its resemblance to a quill or plume, the lamellar 

or fine delicate crystals diverging in such a manner as to 

present this appearance. It is of a pearl-gray color. It is 

found in the United States, at Williamsbury, Mass., Hart- 

ford, Conn.,, and many other places. The green mica is of 

a beautiful grass-green color, and is found in Brunswick, 

Maine. The rose-red mica is a very beautiful mineral, and 

is found in numerous places, in this country ; principally at 

Goshen, Chesterfield, Mass.; Acworth, N. H. ; Bellows 

Falls, Vt., &c. Mica may, when of good colors, be used 

for jewelry and other ornaments, as well as the lepidolite. 

PYRITES. 

This mineral is called sulphuret of iron, iron pyrites, and 

markasite. It occurs crystallized in many forms ; 

such as 

the cube, octahedron, and dodecahedron ; also massive, 

disseminated, capillary, and cellular; 

it has a conchoidal 

fracture ; a brilliant metallic lustre ; its colors are bronze, 

yellow, brass-yellow, and steel-gray. 

This mineral takes a 

very high polish, and from its fine lustre looks extremely

PORPHYRY. 391 

well when cut in the form of a brilliant or rose. It was 

formerly much -used in jewelry for ear-rings, rings, pins, 

and necklaces. It was, in former times, considered a great 

preservative of health. It is now but seldom seen, except 

in mineralogical cabinets. 

ROSE MANGANESE. 

This mineral is called in mineralogical works the silicious 

oxide of manganese, and also the carbonate of manganese. 

It occurs massive; has a foliated structure; a conchoidal 

fracture ; a shining lustre ; it scratches glass ; its colors are 

rose-red, reddish, and yellowish. 

It is found in Siberia, Sweden, Hungary, England ; and 

in the United States, at Middlebury, Vt., and at Cummington 

and Plainfield, Mass., where, according to Professor 

Hitchcock, the silicious oxide, or according to Dr. Thompson, 

the bisilicate of manganese is found in great abundance. 

Since it takes a very high polish, and is much wrought at 

Ekaterinenburg, in Siberia, into many ornaments, it is confidently 

to be hoped that it may also find its amateurs in 

this country, as it is very easy to cut and polish, and the 

material is so plenty. 

PORPHYRY. 

This mineral forms rocks in a geological sense, but is 

properly a compact felspar. It has various' colors and 

shades, and contains imbedded crystals of felspar and 

quartz. The name porphyry signifies purple, from iroptyvpa, 

such having been the usual color of the ancient porphyries ; 

the same rock exhibits, however, almost every variety of 

color ; it is the hardest of all rocks, and when polished, Is 

probably the most enduring. It is much used in Europe 

for ornamental and architectural purposes ; also for slabs, 

mortars, and other articles.


In the United States, porphyry has never been used for 

any purpose ; but Professor Hitchcock f emarks, in his 

Geological Report of the State of Massachusetts, that it 

would be strange if an increase of wealth and refinement 

should not create some demand for so elegant and enduring 

a rock as porphyry. In the same excellent work the author 

divides porphyry into four varieties, as occurring in Massa- 

chusetts, in the neighborhood 

of Boston : 

1st. Compact felspar, with several predominating colors; 

the one with yellow, resembling the Turkey stone; one 

with red, from brownish to blood-red, closely resembling 

jasper ; one with a rose-red color, resembling the rose petro- 

silex of Europe. 

2d. Antique porphyry ; closely resembling that European 

porphyry which was employed by 

the ancients in monu- 

ments and ornamental furniture and forms, and is, when 

polished, a beautiful ornament. It presents numerous varieties 

and shades of color : one of the most elegant is the 

light-green ; then a deep-green ; red of various shades ; 

reddish-brown ; black, or nearly so ; gray, and purple ; and 

the imbedded crystals are usually of a light color, some- 

times white, brown, and greenish. 

3d. Porphyry with two or more minerals imbedded, and 

having a base of common felspar. 

This mineral is between 

sienite and porphyry, resembling the trachytic porphyry, 

and is generally unfit for ornamental purposes ; the quartz 

which it contains is hyaline and smoky. 

4th. The brecciated porphyry, which is composed of an- 

gular fragments of porphyry and compact felspar, reunited 

the fragments are also of 

by a paste of the same material ; 

various colors, usually, however, gray and red ; 

the rock is 

very hard, and when polished, furnishes specimens of great 

delicacy for ornamental purposes. 

Porphyry is much used in England for paving stones, in

SEENITE. 393 

the entrance halls of large public buildings or private 

mansions, and the Cornwall porphyry is particularly cele- 

brated- for its various tints of colors. The author distinctly 

recollects four slabs : one was a black slab ; another, red ; 

a third, green; and a fourth, a large slab, containing 

twenty-four specimens of various variegated rocks of porphyry. 

Also, the elvan-stone, from the quarries of New 

Quay, in Cornwall, which is a beautiful porphyry. The 

large slab, weighing about eight hundred pounds, was of 

very fine red color it was without ; 

flaw or defect. 

In Prussia porphyry is abundant, and there were some 

fine specimens in the London Exhibition, such- as a table, a 

small column and tazza ; 

the latter was a round slab of red 

color and fine texture, and the tazza vase and pedestal were 

of the same material. 

From Sweden and Norway a sienitic porphyry, of grayish-red 

color, was also in the London Exhibition. 

The porphyry vase in the Berlin Museum, which, accord- 

ing to the author's recollection, is about eight feet high 

and six feet in diameter, is well deserving a place hi this 

treatise, as it is unique of its kind in the world. 

SIEXITE. 

This rock is composed essentially of felspar and horn- 

blende, and sometimes contains quartz or mica, or both. 

When polished, it forms the most splendid ornamental 

stone of all rocks ; it is very hard ; and its color and the 

mode of distribution of the various ingredients,' make it 

very agreeable to the eye. It much resembles granite, and 

is often almost identical with it ; 

but by close inspection it 

may be distinguished from the want or addition of the 

component ingredients. 

Professor Hitchcock describes six varieties of sienite:


1st. That sienite which is composed of felspar and horn- 

blende, when the first is white, greenish, and yellowish, and 

the latter inyariably black. 

2d. Felspar, quartz, and hornblende ; the first is foliated, 

and commonly of grayish, bluish, or yellowish color ; the 

second from quite light to dark color and hyaline ; 

and the 

latter is black. Under this variety the quarries at Quincy 

and Cape Ann have been arranged by the author (which 

are generally called granite), on account of the absence of 

mica. The Quincy granite, or rather sienite, is that cele- 

brated architectural material used in the cities of Boston 

and New York, for those huge and magnificent edifices, 

public as wêll as private, erected within the last six years ; 

and it may be supposed that five thousand buildings in the 

city of New York have been constructed with this splendid 

article. 

3d. Felspar, hornblende, quartz, and mica. This rock, 

likewise, has a beautiful appearance, but is, as yet, less 

wrought than the other varieties. The felspar and hornblende 

are predominant. The quartz is in small grains, and 

the mica is black, 

4th. Porphyritic sienite ; its base is quartz and felspar, 

and the hornblende is almost entirely absent ; 

it has a 

porphyritic aspect ; the felspar predominates. It is the 

most ornamental stone when polished. 

5th. Conglomerated sienite; it is a quarternary com- 

pound of felspar, hornblende, quartz, and mica, but all in 

rounded or conglomerated masses, having the aspect of a 

pudding-s'tone ; 

the nodules are from half an inch to six 

inches in size, and may be easily broken out of the mass, 

and the hornblende predominates mostly in them. It is 

unfit for architectural purposes. 

6th. Augite sienite ; in this rock the hornblende ia 

present and rnica absent. It is composed 

of black horn-

SIEXTTE. 395 

blende, greenish augite, and yellowish felspar ; all, except 

the felspar, presenting a crystalline structure; it is also 

composed only of augite and felspar. 

The name of the rock sienite was originally derived from 

Syene, in Upper Egypt, from whence the first specimen 

was procured ; it was examined and identified by Werner ; 

many of the Egyptian monuments, such as Cleopatra's 

Needle, and Pompey's Pillar, were obtained from there. 

There are valuable quarries of sienite in abundance in 

the State of New York. It is a durable and beautiful 

stone, and may be quarried in large' blocks, but on account 

of its great hardness requires much labor to dress it. 

Along the North River there are many 

localities : An- 

thony's Nose, or Anthony s Face, which is a mountain in 

the northwest corner of Putnam county, opposite Fort 

Montgomery. It is called so in consequence of the profile 

bearing a rude resemblance to the human face, that may 

be seen in one position, when passing it ; but on account of 

its steepness, being five hundred feet in height, it is more 

generally called Breakneck Mountain. Here is the granitic 

sienite. It is composed of a darkish-gray colored felspar, 

with a little black hornblende. 

In Peekskill bay, on the Hudson river, and the adjoining 

hills for five miles in length, very valuable quarries of this 

fine rock may be quarried. 

The sienite rock of the Highlands is veTy extensive ; 

such as the Target rock on Constitution Island, opposite 

West Point, and all along the slopes of the mountains in 

the Highlands, there are boulders and blocks of this valu- 

able and useful rock. 

Fort Putnam, near West Point, and the base of Butter 

Hill, four miles north of West Point, are composed of sienite. 

When it was ascertained that the famous rock from 

Syene, in Upper Egypt (so much employed in ancient


monuments), and from which the name of sienite was de- 

rived, was nothing but granite with black mica, and also, 

that Mount Sinai, in Arabia, was composed of genuine 

sienite, a French geologist proposed to substitute sinaite 

for sienite, but the name, although a good one, has never 

been adopted. 

The Quin cy and Cape Ann sienite, which is sent from 

Massachusetts to all parts of the United States, and forms 

such a beautiful architectural material, is composed of 

felspar, quartz, 

and hornblende. 

GRANITE. 

This rock is composed of quartz, felspar, and mica, and 

forms the crust of our globe. It occurs over the whole 

earth, and the eastern part of the United States is abund- 

antly furnished with this valuable mineral. As a building 

material it has been most extensively used for the last ten 

in Decem- 

years ; but the great fire in New York, which, 

ber, 1835, consumed seven hundred buildings, among 

which about two hundred were of granite, has given a 

sufficient proof that granite is> in this changeable climate, 

unfit for a building material, but that it may be usefully 

employed for ornamental and architectural purposes, where 

it is not constantly exposed to the atmosphere and weather, 

which make it so liable to decomposition. 

Nevertheless, granite continues to be generally employed 

in the erection of public buildings, warehouses, bridges, 

&c., and begins to form an important pecuniary object to 

the merchant and mechanic ; and on this account I cannot 

forbear to. treat more fully on its general characters, and I 

must confess that the rich granite treasures of Connecticut, 

Rhode Island, and Massachusetts, which I had occasion to 

examine a short time since, on a journey into those regions,

GEANTTE. 

397 

deserve fully all the encomiums bestowed upon them in 

Hitchcock's Report on the Geology of Massachusetts, and 

in Shepherd's Report on the Geological Survey of Connec- 

ticut. So abundant and large are the granite rocks in the 

eastern part of the United States,* that some single locali- 

ties are sufficient to supply many countries with this lucra- 

tive article. 

Professor Hitchcock divides the granite of Massachusetts 

into four varieties, viz : 

1. Common granite, which, according to him, embraces 

nine tenths of the granite in Massachusetts : the ingre- 

dients are a distinct crystalline structure, of mixed and dis- 

criminating colors. 

2. Pseudomorphous granite is that variety in which the 

mica separates distinctly the other ingredients, which are 

closely mixed. 

3. Porphyritic granite : it contains, besides the usual 

composition of quartz, felspar, and mica, distinct imbedded 

crystals of felspar. 

4. Graphic granite : this variety consists of quartz and 

felspar only ; the cross-fracture presents the appearance of 

written characters. 

Professor Shepherd divides the ornamental granite of the 

State of Connecticut into eight different types, viz. : 

1. Gray granite. 

2. White granite. This variety I have examined myself 

in Plymouth, Connecticut, and so beautiful was its color 

and close granular texture, that I took it at a distance for 

a sandstone, or white marble. 

3. Flesh-colored granite. 

4. Red granite. 

* Professor Hitchcock remarks that there is not a town in Massachusetts 

in which more or less granite does not occur, eiiher as situ or as boulders.


5. Epidotic granite. 

6. Porpbyritic granite. 

7. Chloritic granite. 

8. Sienitic granite. 

In Rhode Island a fine white granite has, according to 

Dr. Webb, of Providence, been employed fgr the erection 

of the arcade of that city, from a quarry in Johnstone, five 

miles from Providence. 

The manner in which granite is usually split out at the 

quarries, is this : a number of holes, of a quadrangular 

form, a little more than an inch wide and two or three 

inches deep, are drilled into the rock at intervals of a few 

inches, in the direction in which it is wished to separate 

the mass. Iron wedges, having cases of sheet iron, are 

then driven, at the same time and with equal force, into 

these cavities ; 

and so prodigious is the power thus exerted, 

that masses of ten, twenty, thirty, and even fifty and sixty 

feet long, and sometimes half as many wide, are separated. 

and it 

These may be subdivided in any direction desired ; 

is common to see masses thus split till their sides are less 

than a foot wide, and their length from ten to twenty feet. 

The price of the granite from these quarries, according 

to Professor Hitchcock, is from forty to forty-five cents per 

superficial foot, and for hammering and fine dressing it, 

about thirty cents the superficial foot, such as in the style 

of the Tremont House in Boston ; common work from 

twenty to thirty-five cents ; posts 

for stone fronts cost 

thirty-four cents per foot. The enterprising citizens of the 

city of New York have erected gigantic monuments of 

granite, for future generations to admire. 

New York abounds in granite, both east and west of the 

Hudson river, Staten Island, Westchester and Putnam 

counties. In the city of New York, a large bed of fine 

granite extends froin. Thirty-first street on the west side,

GRANITE. 399 

and from Twenty-fourth street in the middle, to Sixtieth 

street on the north. The Croton Aqueduct is mostly 

built of granite quarried in Tenth avenue near Forty-eighth 

street. 

Granite abounds in Rockland and Orange counties ; 

occurs in beds, veins, and irregular masses, forming hills, 

and often the tops of mountains. 

The fine-grained varieties of granite are best for eco- 

nomical uses. When granite contains distinct crystals of 

felspar, it is called porphyritic ; when the ingredients are 

blended into a finely granular mass, with imbedded crys- 

tals of quartz and mica, it is called by French writers, 

eurite. A granular mixture of quartz and felspar is called 

pegmatite. 

In England, Cornwall is particularly celebrated for its 

granite ; the obelisk from the Lamorran quarries, twentytwo 

feet high, which was exhibited at the London Exhi- 

bition, was twenty-one tons in weight, and of a coarse 

grain, and another, from Cornseco granite, weighing thirtyone 

tons, and" eighteen feet high, were beautiful specimens 

of this useful rock. They were each wrought from a single 

block of granite, and were remarkable for extreme fineness 

and closeness of grain, and the delicacy of finish which was 

thereby obtained. 

The granite column of Cheesewing granite, the property 

of the Prince of Wales, near Liskeard, in Cornwall, was 

likewise a magnificent piece. It was thirty feet high. 

The bust and pedestal of blue Peterhead granite was 

also an interesting specimen of its kind. 

Swedish granite has been known for many centuries ; it 

is obtained from extensive quarries on the island of Ma- 

leuva, on the west coast of Sweden. It bears a high polish 

it

400 . 

A 

POPULAR TREATISE ON GEMS. 

PEARLS. 

Pearls are concretions, consisting of carbonate of lime, 

having a roundish, tubercular, or angular form ; a white, 

gray, blue, or green color ; 

a shining lustre, and the hard- 

ness of lime; specific gravity, 2*68. They 

are found in 

several bivalve shells the meleagrina margaritifera, haliotis 

gigas, and haliotis iris, and a large species of turbo, which 

shells are known in commerce as flat shells, ear shells, green 

snail shells, buffalo shells, and Bombay shells ; many unios, 

alaniadontas, &c. Mother of pearl is the internal or nacreous 

layer of such shells. These precious substances are the 

result of an excretion in superimposed concentric laminae of 

a peculiarly fine and dense nacreous substance, which con- 

sists of membrane and carbonate of lime. The finest qual- 

ity is produced by the bivalve of the Indian seas, called par 

excellence the pearl oyster (meleagrina margaritifera}. In 

the United States the alasmadonta arcuata, corresponding 

with the mytilus margaritiferus of Barnes, the unio ochra- 

ceus, unio complanatus, and many other species, contain 

the pearls, and according to the nacre of the shells the 

color of the pearl is corresponding. 

The origin of pearls is by some considered to be unfructi- 

fied eggs ; by others, a morbid concretion or calculus, 

produced by 

the endeavor of the animal in the shell to fill 

up holes therein ; by others again, 

as mere concretions of 

the juice of which the shell has been formed, and with 

which the animal annually it. augments It is very plausible, 

however, that the animal of the shell is attacked often 

by enemies, such as the boring shells (turritella), &c. ; 

that 

grains of sand, or any other pointed substance, which, on 

such occasions, come within the shell, stick fast and augment 

with the growth of. the shell; it is also known that 

pearls may be produced artificially, by pressing a sharp

PEARLS. 401 

body on, or by boring a hole in, the shell. The Chinese 

are in the habit of laying a string with five or six small 

pearls separated by knots, inside of the shells, when the fish 

are exposing themselves to the sun, and taking them out 

after some years, whereby they obtain very fine and large 

pearls, and but a little open on the side where they were 

adherent to the shell. The pearl fishers say that when the 

shell is smooth and perfect, they never expect to find any 

pearls, but always do so when it has begun to be deformed 

and distorted. It was therefore concluded, that as the fish 

grew old, the vessels containing the juice for forming the 

shell and keeping it in vigor, became weak and ruptured, 

and from this juice accumulating in the fish, the pearl was 

formed, and the shell brought to decay, as supposed by M. 

Reaumur. It would be, according to this idea, a sure 

guide to know from the form of the shell, whether the 

pearl is large or small; and thus by the smaller ones being 

thrown back into the sea, a constant crop of large pearls 

might be obtained. The mother-of-pearl fish is found in 

the East and West Indies, and other seas in warm latitudes, 

and in the rivers of north and middle Europe. In some 

parts of the globe, they are found in clusters, containing a 

great number; the places where found are caUed pearlbanks. 

The most famous are near the coast of Ceylon, 

that of Japan, and in the Persian Gulf, near the island of 

Bahreim ; also near the coast of Java, Sumatra, &c. The 

finest and most costly pearls are called the Oriental, and 

are from the above places ; they are all white or yellowish ; 

those from, the Persian Gulf, on account of their perfect 

whiteness, are preferred to those from Ceylon. Pearls are 

collected in rivers with the hand, but in seas it is the busi- 

ness of divers, brought up to this most dangerous occupation 

from early youth. In the East Indies there are two 

seasons for pearl fishing ; the first in March and April, the

402 A POPULAR TREATISE (N GEMS. 

and the more rain, the 

second in August and September ; 

more productive are the pearl fisheries. In the beginning 

of the season there are sometimes two hundred and fifty 

the larger barks have two divers, the 

barks on the banks ; 

smaller, one. The divers descend from their barks with a 

rope round their body, and a stone of twenty or thirty 

pounds attached to one of their feet, so that they may sink 

speedily from eight to twelve fathoms, where they meet 

the shells fastened to the rocks ; the nostrils and ears are 

stuffed up with cotton, and to the arm a sponge dipped in 

oil is fastened, which the diver now and then brings to his 

mouth, in order to draw breath without swallowing water. 

He also carries down with him a large net, tied to his neck 

by a long cord, 

the other end of which is fastened to the 

side of the vessel, to hold the shells, and the cord is to 

draw him up when the net is full, or when he wants air ; 

he has likewise a knife or an iron rake, for detaching the 

the shells from the rocks. Thus equipped, he precipitates 

himself to the desired depth, where he can very distinctly 

see all that is passing around, yet cannot escape in time the 

sudden approach of sharks, to whom he too often becomes 

a prey. When the diver has been in water some minutes, 

and has his net filled, or is unable to stay any longer, he 

loosens quickly the stone at his foot, shakes the line, and 

he is drawn up by his companions. The diving-bell is now 

more so than in former years. 

frequently used ; 

In the Persian Gulf the divers rub their bodies with oil, 

and fasten a stone of about fifty pounds to their feet. 

The shells obtained are piled up in heaps, and left ex- 

posed to the rain and sun until the body of the animal 

putrefies, and they open of themselves. Those containing 

any pearls have from eight to twelve. After being picked 

out, washed, and dried, they are passed through nine sieves 

of different sizes.

PEARLS. 403 

At the Pearl Islands, near the Isthmus of Panama, the 

pearl fisheries have, within a few years past, become a 

lucrative business to many of the inhabitants. The clivers 

use more simple methods than those we have mentioned, 

for collecting the pearl oysters : they traverse the bay in 

canoes that hold eight men, all of whom dive naked into 

the water, from eight to ten fathoms deep, where they 

remain about two minutes, during which time they collect 

all they can with their hands, and dexterously rise to- 

deposit them in their canoe, repeating the operation for 

several hours. 

In Sweden, the pearl oyster is caught with a pair of 

long tongs. The fishermen are in small boats, painted 

white on the bottom, which reflects the light to a great 

depth, and as soon as they perceive them passing underneath 

they seize the oyster. 

Pearls are esteemed according to their size, form, color, 

and lustre ; 

the largest, of the size of a small walnut, are 

called paragons, which are very rare ; those the size of a 

cherry, are found more frequently, but still are rare ; they 

are the diadem or bead pearls. They receive names, also, 

according to their form, whether quite round, semi-circular, 

and drum-form, or that of an ear-drop, pear^ onion, or as 

they are otherwise irregularly shaped. The small pearls 

are called ounce pearls, on account of being sold by weight, 

and the very smallest, seed pearls. Those of a brilliant 

white color, or white water, are most sought for in Europe ; 

those of a yellowish color in some parts of Asia ; 

and some 

of a lead color, or those of a jt black, are preferred among 

some nations. They all turn more or less yellow with age, 

and to restore the white color, they are either baked in 

bread, rubbed with boiled salted rice, or kept for a short 

time in the gastric juice of fresh-killed chickens. 

Pearls are sold by weight troy weight j but the penny-

404 -A POPULAR TREATISE ON GEMS. 

weight of twenty-four grains is counted as thirty ; 

so that 

an ounce has six hundred grains, pearl weight, and four 

troy grains are equal to five pearl grains. The price 

has, within the last forty years, much diminished, for two 

reasons : 

1st. Diamonds, and particularly brilliants, have become 

more plentiful, and have since been worn, not by the higher 

classes alone, but also by the middling. 

2d. Within the last twenty years, artificial pearls have 

been manufactured in high perfection, and are worn to a 

great extent. 

It is my opinion, however, that the price of pearls will 

take a fresh rise among the nobility and richer classes, 

diamonds being now so generally worn ; 

as persons, think- 

ing to invest safely, without any future loss, their surplus 

capital, purchase brilliants that formerly were possessed 

exclusively by the rich. 

Pearl fisheries were first carried on in remote times in 

the Persian Gulf, and the most celebrated, formerly, were 

near the island Bahreim. Five hundred thousand ducats 

was then the yearly produce. About one million dollars' 

worth, at the present time, are exported. The island 

Kharack now produces the most considerable quantity. 

The principal market is at Muscat ; from thence they are 

brought to Surat. The mode of procuring them pursued 

in those countries, is in canoes, holding fifteen men, six of 

whom are divers: the shells caught during the day are 

delivered to a surveyor* when they are opened on a white 

cloth, and whoever finds a pearl of some value, puts it in 

his mouth, to give it, as they say, a " better water." The 

greatest harvests are generally after many rains, and the 

largest pearls are mostly found in the deepest water. At 

Ceylon the pearl fisheries are now considerable, particularly 

in the bay of Condatchy. The shells are there left to

PEARLS. 405 

reach the age of seven or eight years, and in the fourth 

year they have small pearls, sometimes a hundred and fifty. 

They fish yearly, in the month of May, during four weeks. 

In the year 1804, eight hundred canoes, each with two 

divers, were engaged. Before the year 1800, the pearl 

banks were leased, to an Indian merchant, for three hun- 

and before the arrival of the Euro- 

dred thousand pagods ; 

peans in India, the same bank was used every twenty or 

twenty-four years ; when under the Portuguese,.every ten, 

and under the Dutch, every six years. In 1800, the 

produce was from one hundred to one hundred and fifty 

thousand pounds sterling. 

Japan has some pearl banks, which are, however, not 

much sought ; the same may be said of the Nipthoa lake, in 

Chinese Tartary. America sent, in the sixteenth century, 

pearls to the amount of eight hundred thousand dollars to 

Europe. The shells were mostly collected from Cape Paria 

to Cape Velo ; round the islands Margarita, Cubagua, 

Coche Punta, Aragy, and at the mouth of Rio la Hacha," 

from which latter locality, and the Bay of Panama, Europe 

is now mostly supplied. The former localities have long 

since been relinquished, on account of their small produce ; 

too many shells having been removed at one time, thereby 

retarding the growth of pearls. Panama has sent, within 

a few years past, about one hundred thousand dollars' 

worth of fine pearls to Europe, the trade being carried on 

of Panama. The coast of Florida is said 

by Messrs. Plise, 

to have been vefy lucrative to the Indians, as a pearl 

fishery, which, however, does not prove so now, since 

settlement of civilized people. 

the 

England used to be supplied from the river Con way, in 

Wales ; and Scotland supplied the London market, between 

the years 1761 and 1764, to the amount of ten thousand 

pounds sterling ; but the supply has failed. Pearls are


found in the Elster river, in the kingdom of Saxony, from 

its source at the borders of Bohemia to Elsterberg, where 

the fishery has been jcarried on since 1(521, with some ad- 

vantage to the sovereign ; some pearls found there were 

valued at fifty Prussian dollars each. In the river Watawa, 

in Bohemia, and in the Moldau river, from Kruman to 

Frauenburg, pearls are found of great beauty; 

so much so 

as to equal in price the Oriental pearls. Also, at Rosenberg, 

pearls are* sometimes found superior to the Oriental in 

and at Oelsnitz, a considerable pearl fishery is car- 

lustre ; 

ried on. Most of the rivers in Sweden, Lapland, Finland, 

Poland, Norway, Jutland, Silesia, and other places, contain 

pearls, but they are not collected. 

It is a "fact that the pearl is equally hard throughout all 

. its concretional layers, for by putting the pearl in a weak 

acid, the outside layer becomes gelatinous, arid the succeeding 

layers are found to be equally hard and uniform. 

It is almost impossible, therefore, that the story told of 

Cleopatra having swallowed a pearl after being dissolved 

in vinegar, should be true ; besides, if the pearl had been 

dissolved as quickly as reported, it would not have made 

a very disagreeable beverage. Pearls were known, and 

were very much esteemed by the Greeks and Romans, and 

when they became acquainted with the Indies, by com- 

mercial intercourse and conquest, they preferred the pearls 

of the East to those that were obtained from the rivers of 

Europe, or even from the Mediterranean. 

With the ancients the wearing of this species of curiosity 

became a passion and even a folly. Necklaces, bracelets, 

and ear-rings were then worn in profusion ; dresses, head 

and foot ornaments were manufactured with pearls. 

Mil- 

lions of sesterces (a Roman coin of two hundred francs 

value), were expended and lavished for the best and most 

extraordinary pearls. The two pearls of Cleopatra cost

PEARLS. 

407 

nearly two millions of francs ; Julius Caesar presented to 

Servilia, the sister of the celebrated Cato, of Utica, a pearl 

which he purchased for one million two hundred thousand 

francs-. 

Lollia Paulina, the wife of Caligula, wore ornaments to 

the value of eight millions of francs. The ladies went so 

far as to ornament their buskins with pearls. Nero lav- 

ished pearls upon his lewd women. In modern times 

Buckingham distributed in the halls of the Empress Ann, 

of Austria, and of King Louis XIII., pearls to the value of 

three hundred thousand francs. 

The baroques, which are excrescences in the mother of 

pearl, are sometimes very large, and display some extraordinary 

figures and inconceivable freaks of nature. They 

are held in high estimation, and are mostly worn in Spain 

and Poland. 

Caire, the celebrated French jeweller, possesses many 

baroques ; one representing a bearded dog ; 

" 

another, rep- 

resenting the order of the fleece. He had a mother of 

pearl containing a large excrescence, representing a Chinese 

with crossed legs. 

The prices of pearls, from one carat upwards, were for- 

viz : if the carat 

merly determined like those of diamonds, 

b fixed at five dollars, and a pearl weighs four carats, take 

the square, or sixteen, which multiplied by five is equal to 

eighty; so that a pearl 

of four carats was estimated at 

eighty dollars. 

At present the following are the prices of pearls : 

1 grain is worth, in France, 4 francs per carat. 

it " 

9 K c 

|0 

3 

" " " 25 

" u 

4 

" 

(1 carat) 

" 

50 

" " 

The baroque pearls are sold at from three hundred to 

one thousand francs per ounce.


The seed pearls, when quite round, are worth about one 

hundred and twenty francs per ounce. 

In France, perforated pearls are valued at twice the 

prices given above. The piercing of the pearl is well understood 

in the Indies. The value of a pearl is always 

those that have a 

enhanced by size, perfection, and color ; 

yellowish-white, or silver-white, or very pale gold-yellow 

shade, or a rose or lilac color, are the most esteemed 

pearls. 

The French pearl fisheries produce at least from three to 

four millions of franco. 

The French Crown possesses pearls of immense value : 

One round virgin pearl, of a magnificent orient, weighing, 

5 

27T g- carats, is valued at two hundred thousand francs. Two 

pear-shaped pearls, well formed, of a beautiful orient, and 

weighing together 57y^ carats, are valued at three hundred 

thousand francs; 

6 

two ear-drops, weighing 99T^ carats, are 

valued at sixty-four thousand francs. 

About seventy-two more large pearls, of great beauty 

and exquisite form, pear-shaped and round, valued in the 

aggregate sum of three hundred and fifty thousand francs. 

At the Paris Exhibition, in 1855, an enormous pearl, of 

pear-shape, brought from Berlin, by Napoleon I., was 

exhibited. 

The Princess Royal of England, at her marriage to 

Prince Frederic William, of Prussia, .wore a necklace of 

the finest pearls, which cost, at the least calculation, five 

hundred thousand francs. 

The Emperor Rudolph possessed a pearl weighing one 

hundred and twenty grains. 

King Philip II., of Spain, possessed a pear-shaped pearl 

of the size of a pigeon's egg, weighing one hundred and 

thirty-four grains. It came from Panama, and was valued 

at fifty thousand ducats. It was called the Peregrina.

PEAKLS. 

409 

In 1620, King Philip IV., of Spain, purchased a pearehaped 

pearl from Gougitas, of Calais, which weighed four 

hundred and eighty grains. An anecdote is told of the 

King, who asked the merchant how he could risk his whole 

fortune in so small a piece as that pearl ; whereupon the 

merchant replied, that he knew there was one king of 

Spain in the world who could afford to it. purchase It 

now belongs to the Princess Youssopoff. 

A costly collection of pearls from the Indies, Ceylon, 

and Singapore, and innumerable pieces of ornamental jewelry 

set with most costly pearls, was exhibited at the London 

Exhibition by Messrs. Garrard, Hunt, Roskell, and 

other jewellers. 

A large pearl, from Vermont, United States, weighing 

eleven carats, and very round, but not of bright color, is 

in the possession of Mr. S. H. Palmer. 

Messrs. Blogg & Martin, of London, inform me, under 

date of April 25, 1859, that they have in their possession a 

magnificent pearl necklace, consisting of thirty-seven perfect 

pearls, of forty grains each ; they sent a description of 

it, and also of two beautiful pearl-drops, which they value 

at two thousand pounds sterling. The necklace and drops, 

which must be unique specimens, deserve more than "a 

mere notice, but the description came too late for insertion. 

United States Pearls. 

New Jersey merits the credit of producing fine pearls ; 

a great many thousand pearls have been obtained from the 

mussels, which compare fairly with those of the India pearlshell 

; size, color, nacre, and orient are displayed in many 

of the New Jersey pearls in a high degree, and are now 

passing in Europe for the genuine 

Oriental or Panama 

pearls. In 1857, a shoemaker named David How ell, living 

18

410 


Fig. 14.

Fig. 15. 

PEAHLS. 411 

Fig. 12 J. 

Fig. 16.


near the town of Paterson, New Jersey, went to a neighboring 

brook, called Notch brook, in order to collect some 

mussels for his breakfast, and, on opening them, discovered 

a great many loose pearls falling out, which he took to a 

jeweller in Paterson, who stated to him that they were 

valuable, and they both began to collect millions of these 

mussels, and their efforts were crowned with success. The 

preceding representation of the mussel belongs to the great 

family of unio, which was formerly called the avicula mar 

garitifera, mya margaritifera, but now known as an alasmadonta 

arcuata named by Barnes. Many unios (of 

which there are, according to Lea, Say, and other Ameri- 

can conchologists, over six hundred species), contain pearls 

more or less and Mr. John H. ; Redfield, the efficient 

corresponding secretary of the New York Lyceum of 

Natural History, informs me that he found the pearls in 

the same locality in New Jersey, in three or four other 

unios, such as the unio complanatus, unio ochraceus, unio 

radiatus, &c. A very perfect pearl in the shell may be 

seen in the annexed drawing, which is copied from " Frank 

Leslie's Illustrated News" of May, 1857; the pearl is rather 

dark, and the shell, as may be seen, appears worn off. 

This is one of the characteristics of the shells containing 

pearls, and it appears to indicate that the animal is in the 

decline of life, and that the mussel is becoming gradually 

decayed. 

The streams in which these pearl shells are found are 

generally very shallow, not more than one or two feet 

deep, and the shells may be picked up with the hands; 

many thousand shells are opened, containing deposits of 

the pearly matter, most of which contains shapeless and 

colorless pearls^ which are so small that they -are of no 

value ; many, however, contain very perfect pearls ; the 

crown-pearl, weighing ninety-one grains, in the possession

PEARLS. 413 

of Messrs. Tiffany & Co., was purchased from Mr. Howell 

for $1500. This pearl resembles a crown, having three 

smaller pearls resting upon the large pearl ; 

another repre- 

sentation of a pearl weighing nearly four hundred grains, 

here represented, was destroyed by cooking the mussel in. 

order to open it better, and the color of the nacre has 

been spoiled ; it would, probably, have been the largest 

pearl of modern times, and of immense value. 

The alasmadonta of the present day was formerly called 

mya, from the Greek fiva), to compress, it is called in 

English, the gaper, on account of the bivalve gaping at one 

end, its hinge having a solid, thick, patulous tooth, seldom 

two, and not inserted in the opposite valve; the same 

genus was originally called mytilus; they inhabit both 

the ocean and fresh 

mud at the bottom. 

water; they perforate the sand or 

Many species are caught for food, 

and others for the pearls; some few of the same genus 

perforate and live in limestone, like the pholadites. 

The pearl-bearing mya, now alasmadonta, is frequently 

found in the large rivers of northern latitudes. The Brit- 

ish Islands, especially Ireland, were formerly famous for 

their fisheries, and a few pearls of great value have at times 

been obtained from these sources, although 

the British 

specimens are not held in high estimation, with the exception 

of a few procured from, the river Shannon, in the 

year 1821. 

The river Irt, in Cumberland, the Conway, in Wales, 

and the Tay, in Scotland, were once noted for their pearl 

fisheries. Suetonius reports that Caesar was induced to 

undertake his British expedition for the sake of the pearls ; 

and according to Pliny and Tacitus, he brought home a 

buckler made with British pearls, which he dedicated to, 

and hung up in the temple of the idol Venus genetrix. 

The gapers are mostly used for food, both in Britain


and on the Continent ; around Southampton, in England, 

these mussels are known by the whimsical name of " old 

maids," and the inhabitants of the northern islands call 

them smuslin, and consider it a fine supper-dish, which is 

by no means unpalatable.* 

I am informed by Mr. Plise, who brought a considera- 

ble quantity of pearls from Panama, that he receives four 

dollars per grain in England, for those of good size and 

quality. 

Pope Leo bought a pearl for eighty thousand crowns. 

Tavernier describes one belonging to the King of Persia, 

which is said to have cost one million six hundred thousand 

livres. Portugal has a pearl in her treasury of the size of 

a pear. Two Greeks, residing in Moscow, are in posses- 

sion of a pearl weighing twenty-seven and seven eighths 

carats. 

For restoring Oriental pearls to their original lustre, 

which they lose in the course of time, the following process 

is resorted to in Ceylon : the pearls are allowed to be 

swallowed by chickens, which are then killed, and the 

pearls are an hour afterwards taken out of the stomach, 

when they are as white and as lustry as if just taken from 

the shell. 

The poet Cowper thus expatiates on the mussel: 

" Condemn'd to dwell 

Forever in his native cell ; 

Ordain'd to move where others please, 

Not for his own content or ease ; 

But toss'd and buffeted about, 

Now in the water and now out ; 

Yet in his grotto-work inclosed 

He nothing feels in that rough coat, 

Save when the knife is at his throat; 

Wherever driven by wind or tide, 

Exempt from every 

ill beside."

PEAELS. 415 

Artificial Pearls. 

Artificial pearls or beads are of various kinds; most 

generally they consist of solid masses of glass, with a hole 

or they are blown hollow, and then filled 

drilled in them ; 

out with metallic lustry grains, wax, or with the fine scales 

of the bleak fish, which have a silvery and pearly lustre. 

The art of imitating pearls is attributed to a manufac- 

turer of beads, of the name of Janin or Jalquin, who lived 

at Paris in 1680; he was led to the discovery by seeing, 

one day, the scales of the bleak fish swimming in a trough, 

where the fish detached them by rubbing against each 

other, and he at once conceived the idea of applying these 

scales for imitating the orient of the pearls, by mixing 

them with a mucilage and filling the interior of hollow 

glass bulbs, and he gave this natural and wonderful production 

the name of Extract of Orient a very singular 

name, but still significant of the meaning of its employment. 

It is well known that this little white fish, the bleak, is 

found in abundance in the rivers Seine and Marne, in 

France, and in many small rivers in Sweden, Germany, 

and Italy. The bleak fish fructifies around water-mills, 

where they are caught by nets. 

For the purpose of extracting the color of the scales of 

the fish, they are rubbed pretty hard in the fresh water 

collected in a stone basin, which settles down in the bottom 

of this vessel ; the sediment is then pressed out through 

a linen rag, and they are then replaced again in fresh 

water and left there to settle for several days, when the 

water is drawn off and the precipitate is carefully collected ; 

this is called the extract or essence, and it requires from 

seventeen to eighteen thousand fishes to obtain five hun 

dred grammes (a little over one pound). 

The scales being animal matter are, therefore, liable to


decomposition, and for their preservation numerous chemical 

agents have been employed by the different manufac- 

turers, all of whom, who have succeeded, keep it a secret ; 

it is, however, known that liquid ammonia is added to the 

paste of the scales. . 

The operation of the manufacture is very difficult, but 

an experienced workman can manufacture six thousand 

pearls in a day. 

The chemists have experimented for some years to imi- 

tate the extract of orient, as it requires such a large 

and 

quantity of fishes to obtain any amount of the scales, 

according to Mr. Barbot, the following preparation has 

produced a favorable result : which is by distilling one part 

of oxide of bismuth and two parts of corrosive sublimate ; 

the product is a species of butter, which on redistilling 

yields metallic quicksilver and a very fine powder ; 

this is 

the substance used for orientalizing or coating the artificial 

pearls with the true gloss- of an Oriental pearl. 

The same scales are likewise used to coat beads of gypsum, 

or alabaster, which are soaked in oil and then covered 

with wax to give them a pearly appearance. The Roman 

beads are made in this manner : the scales are dissolved 

either in liquid ammonia,- or vinegar, and the solution or 

liquid is used for covering those artificial beads. The Turkish 

rose-beads are made of an odoriferous paste, and are 

turned afterwards like those of coral, amber, agate, or 

other hard substances. The knitting beads are sold in 

meshes of one hundred and fifty, or twenty strings, of 

fifty beads each, of various colors ; and the large glassbeads 

in meshes of twelve strings. There are numerous 

manufactories in Germany and Italy of the various kinds 

of beads, which are used to a very great extent both in 

Africa and North and South America. Germany exports 

yearly from its different manufacturing places, such as

PEARLS. 417 

Heidelberg, Nuremberg, Sonnenberg, Meistersdorf, in Bohemia, 

and Mayence, more than a million dollars' worth. 

In Venice are large establishments for the finest cut beads. 

Nuremberg manufactures, besides glass beads, considerable 

quantities of amber beads. In Gablontz, in Bohe- 

mia, more than six thousand persons are engaged in the 

manufacture of beads, that are made of pure glass, or of a 

composition. From the glass-houses, which are very 

numerous in Bohemia, the rods of different sizes are 

delivered to the glass mills for cutting, which is performed 

by water power or by hand. In 1828 there were in that 

neighborhood one hundred and fifty-two mills in operation; 

a number of glass-blowers were likewise engaged, who 

possessed great dexterity in blowing the small beads with 

the assistance of a small blow-table. In the manufactory of 

George Benedict Barbaria, at Venice, six hundred varieties 

and that of Messrs. Gas- 

of beads are constantly making ; 

pari and Moravia manufactures, besides the beads, every 

article of jewelry from the same material. 

The rose beads of Steffansky and Tausig, are made of 

bread crumbs, which are beaten up with rose water in a 

wooden mortar, until they become a uniform mass, to 

which is added some otto of roses and drop-lake, when it is 

made into beads with dissolved gum tragacanth ; for the . 

black rose-beads, Frankford black is substituted hi the 

place of the drop-lake. 

Lamaire, of France, manufactures beatfs equal in lustre 

and beauty to real pearls. He adds to 

1000 ounces of glass beads, 

3 

^ 

1 

" 

" 

" 

scales of the bleak-fish, 

fine parchment glue, 

white wax, 

1 

" 

pulverized alabaster, 

with which he gives them an external coating. 

18


Rouyer manufactures his beads, also in France, from 

opal, which he covers with four or five layers of dissolved 

isinglass, and then with a mixture of a fat oil, spirits of 

turpentine, and copal, so as to prevent their becoming 

moist. In order to render them of the peculiar lustre of 

the Oriental pearls, they are covered with a colored enamel. 

The opal is fused into rods by a lamp, over which is laid a 

brass wire to support it ; 

the wire is held in one hand and 

the opal in the other, and the wire is then kept turning 

until the bead has the desired size and .roundness; if a 

colored enamel is to be applied, the beads are made but 

half the required size, which being done, they are once 

more covered with the opal, then the solution of isinglass 

is used, and lastly the varnish. Beads made in this man- 

ner are with difficulty distinguished from the Oriental 

pearls. 

The best method of making artificial 

pearls, is certainly 

by means of pulverized real pearls. Either the smallest, or 

the deformed large specimens, may be reduced to a fine 

powder, and then soaked in vinegar or lemon-juice, and 

the paste made up with gum tragacanth ; they may then be 

cut out with a pill machine, or a silver mould, of any desired 

size, and when a little dry, inclosed in a loaf and baked in 

an oven : by tin amalgam, or by the silver of the scales of 

young fish, the proper lustre may be given. 

The artificial pearls, by Constant Vales & E. Truchy, of 

Paris, which were on exhibition in the London Crystal 

Palace, were extremely beautiful, and were with the 

greatest difficulty distinguished from the natural pearls. 

Messrs. Bouillette, Hyvelei & Co., of Paris, exhibited, 

besides many beautiful pearls, a great variety of artificial 

stones, all of their own manufacture, and very tastefully 

set ; among them was a stomacher in diamonds, pearls, and 

emeralds.

CORALS. 419 

The shad-fish, as well as the white-fish of our lakes, must 

yield an extract of orient, of as good a quality as the bleak- 

fish of the Seine, and it is to be hoped that some enter- 

prising mechanic may take an opportunity of preparing the 

white matter adhering to the scales of the fish just men- 

tioned, either for export, or for the purpose of imitating 

pearls, which may be done as well in this country as anywhere 

else. 

The usual price of false pearls is two dollars and fifty 

cents a string, one hundred to the string ; but some are 

lower, and some higher, according to color. 

CORALS. 

Corals are zoophytes, whose calcareous habitations resem- 

ble vegetable branches. They live in the sea, adhering to 

rocks, stones, or vegetables, and shoot to the surface of the 

water in tnbiform stems with branches, generally coated 

with a gelatinous or leathery skin that incloses a cartilaginous 

marrow, composed of many cells, inhabited by the 

animals, who propagate in sprouts from eggs so fast, that 

small reef-rocks are formed, which in the course of time 

become islands. 

The red coral, or precious coral (iris nobilis), belongs to 

that family of zoophytes which live mostly in the cavities 

of rocks in the sea ; the stem is always of a beautiful red 

color, rarely white ; quite compact, striated on the outside, 

of entire calcareous composition ; it grows one foot high 

and an inch thick. The stem is covered with a leathery 

crust, containing open warts of eight teeth, in which the 

animals, or polypi, with their eight arms, are situated ; 

the 

arms are whimpered, and the animal grows very slowly. 

The red coral is fished up with nets of strong ropes, fas- 

tened on large wooden cross-beams, which are thrown


down on the places where the corals are known to be fas- 

tened, and an expert diver contrives to entangle the nets 

in the reefs, which are then drawn up by force. The corals 

so brought up are cleaned, assorted, and sold to the manu- 

facturers. 

Messrs. Payenne & Laminal have invented a very ingenious 

machine for collecting the coral from the banks of 

the ocean, without breaking the fine branches and without 

injuring the banks which are formed for the growth of the 

coral. 

It is a fact admitted by naturalists and fishermen, that 

the growth and accumulation of the zoophytes take place 

continually in the same waters ; and that as great and pro- 

the fish- 

lific a traffic may be created by coral catching as by 

eries in France. Lord Ellis proved, in 1754, that the coral 

polype possesses an ovarium filled with small eggs, pre- 

pared for hatching ; all these eggs are attached together 

by a species of cordon, and resemble worms ; tentacles are 

shooting out from them, which move in the same manner 

a$ the grown polypes. 

In 3856, Mr. Focillon presented a report to the Acclimi- 

tation Society at Paris, on the methodical exploration of 

the ancient and natural banks, and on the construction of 

artificial coral banks in such a manner as to secure the 

most favorable position for the production and operation 

of an easy and sure coral harvest. Facts have already 

been elicited, that the new coral succeeds so well at a 

depth of seven to eight metres (twenty four feet), under 

the influence of the rays of the sun, that it develops quickly, 

and becomes large and of good color at the end of eight or 

nine years; while a coral at a depth of thirty to fifty 

metres (one hundred and fifty feet), requires from thirty- 

five to forty years to shoot out, and it is not then of as 

good a color as the former. This discovery ought to

COEALS. 421 

stimulate the African coast (Algeria), particularly the in 

habitants on the shores of Bona, Oran, and other places, 

who ought to be beforehand in the application ; also on the 

Marseilles coast, which is already full of coral reefs. . 

Coral was formerly cut in facets, and was in great favor 

under the consulate and empire of France, for almost every 

species of luxury ; combs, ear-rings, necklaces, beads, 

but 

crosses, &c., were manufactured and sold at high prices ; 

the fashion and price soon fell. Ten or fifteen years after- 

wards an endeavor was made to bring coral in vogue again, 

by offering coral engraved as cameo, and made into other 

ornaments, such as brooches, bracelets, ear-rings, and pins, 

which were then sold pretty high ; but on account of an 

insufficient supply of the article and bad workmanship, it 

fell back to its original lethargy, and for many years it was 

considered worthless and altogether out of fashion. 

During the last two years, coral has resuscitated very 

much, and got into good grace with the ladies. 

The Parisians have, however, changed their taste for the 

former favorite, the red coral ; the rose-colored, cut in a 

round form, so as to nearly resemble a rose pearl, being 

preferred, which is acknowledged to be extremely rare. 

The price of these rose'-colored corals has of late risen so 

high, that a fabulous sum is paid for them; and a coral 

which was worth but fifty francs in 1810, is now sold for 

three hundred francs and upwards. At present the fashion 

for corals is at its height, and ornaments of every con- 

ceivable variety may be seen in the shops of jewellers in 

this country, imported from France and Italy. . 

At the last Paris Exhibition there was a coral chess- 

board, with all its figures representing an army of Crusaders 

and of Saracens, which was admirably executed, and 

valued at 10,000 francs. Coral branches, if. without a frac- 

ture, bring a great price.


France manufactures and exports coral ornaments to the 

value of six millions of francs, and the demand for them 

is much greater; the establishments of Barbaroux and 

Garaudy & Fils, in Marseilles, where the coral is 

principallymanufactured 

into ornaments, give proof that France will 

retain the supremacy in this species of luxury. 

In the Paris Exhibition of 1855, many curious sculptured 

and chiselled objects were shown by Arsene Gourdin, of 

Paris. 

In the London Exhibition, fine corals were shown from 

the Cape of Good Hope, from Reftaelli & Son, in Tuscany; 

from Algiers .was also a collection. Tucker & Co., of Ber- 

muda, exhibited a fine collection of both corals and madre- 

pores, including the black flexible coral (gorgonia). 

Among the ancient rare coral engravings is the head of 

the philosopher, Chrysippe, in high relief: it was in the 

Orleans collection. A coral cameo of the 14th or 15th 

century, representing a Sphinx with three Cupids, well 

executed, is mentioned by Caire. 

The red corals are distinguished by the names of the 

countries where found. 

1. The Barbarian, which are the thickest and purest. 

2. The Corsican, which are the 'darkest, but not so thick, 

and less pure. 

3. The Neapolitan, and those from Ponza, which are 

clear and pretty thick. 

4. The Sardinian, which are thick and clear. 

5. The Catalonian, which are nearly as dark as the Cor- 

sican, but mostly thin. 

6. The Trapanian corals, from Trapani, in Sicily, which 

are somewhat preferred at Leghorn. 

The darkest corals are most liable to be worm-eaten. 

The polished corals are generally sold in bundles, which 

consist of a certain quantity of strings, of a certain weight.

CORALS. 423 

They are strung in Leghorn, either of various or equal 

thicknesses, which latter are then of various sizes, and the 

bundles receive their names accordingly; grossezze, mez- 

zanie, filotti, capiresti, &c. The thickest corals are put 

up in one string, resembling a tail, and are called codini ; 

the smallest are called smezzati. 

At Genoa, the various large corals are called mezza- 

nie j the uniform large, filze / and the uniform small, 

migUari. 

They are distinguished according to color at Leghorn ; 

the darkest red are called arcispiuma, Avhich are the dearest ; 

and then primo, secundo, terzo, quarto, coloro or sangue, 

chiari, moro, nero, &c. 

According to form they are called round (tondi), and 

cylindrical-round (boticelli). The former are sent to all 

parts of the world, but the latter are only sent to Poland. 

The large boticelli are put up in meshes of twelve pounds, 

and the middling size of the 

containing thirty-six strings ; 

boticelli are in meshes of six pounds, containing sixty 

strings; those boticelli which are still larger, are called 

olivatti, and are only sent to Africa ; those which are globular, 

and not drilled, are called paUini altorni, and sent 

principally to China, where the favorite color is the rose- 

red. 

The sound corals are called netti, and the worm-eaten, 

camolatti, which latter are mostly sent to the East Indies. 

The tops of the branches are called dog-teeth, or dents 

canines, and the thick ends of the branches are called mao- 

metti both kinds are perforated lengthwise, and are used 

in Barbary as ornaments for horses. The fine large coral 

stems which form suitable specimens for cabinets of natural 

history, in Marseilles, are called chouettes. 

There are one hundred varieties of shades of red coral 

distinguished at Marseilles.


Corals are principally used for ornaments, in the East 

Indies, China, and Africa, where they are preferred to the 

diamond. Almost every East India lady wears a bracelet 

or necklace of corals. 

The white coral has its origin from the eight-star coral 

(rtiadrepora occulta)] and the black coral from the black- 

horned coral (gorgonia antipotlies) . The medusa head 

(caput medusce), called the sea polen, belongs likewise to 

the coral family, and consists of sixty-two thousand six hun- 

dred and sixty-six articulated members. 

Corals are fished for on the coast of Barbary, between 

Tunis and Algiers ; 

in the latter state Bona is the principal 

the French have one also at Basteon de France. 

The monopoly was purchased by France, in the seven- 

station ; 

teenth century, at eighteen thousand dollars annually; and 

by England, since 1806, for fifty thousand dollars. 

At Bona there is a summer fishery, from the first of 

April to the first of October, which occupied, in 1821, 

thirty French, seventy Sardinian, thirty-nine Tuscanian, 

eighty-three Neapolitan, nineteen Sicilian barks ; alto- 

gether, two hundred barks of two thousand and twentythree 

tons capacity, with two thousand two hundred and 

seventy-four men ; they fished up forty-four thousand two 

hundred pounds of coral, valued at two million four hun- 

dred thousand francs. The winter fishery of the same year 

occupied three French barks, each with nine men, and they 

obtained six hundred and eighty pounds of coral. 

The principal manufactories of corals are now at Leghorn, 

where this branch of business has been carried on for 

two hundred years past, by the Jews. There were for- 

merly twenty establishments, but the number has lately 

been much diminished. 

They are sent principally to China, the East Indies, and 

Arabia, partly by the way of London, and partly by Mos-

SHELL CAMEOS. 425 

cow, Aleppo, and Alexandria; many corals are likewise 

sent to Poland. 

Genoa has a few manufactories, in which the Sardinian 

corals are mostly wrought. At Marseilles there has been 

a large manufactory ever since 1780, and at present it is 

the only establishment of the kind in France. 

The East Indies consume, according to the statement of 

Le Goux de Haix, nearly four million francs' worth. 

Corals are worn in the East as ornaments in the turban, 

and the Arabs bury the coral with their dead. 

A large coral, from the manufactory at Marseilles, was 

sold in China, to a mandarin, for twenty thousand dollars. 

Purpurin is the name of artificial coral. A large quantity 

of this false and base imitation of coral has been im- 

ported into this country. It is used for setting in cheap 

jewelry; brooches, bracelets, ear-rings, and pins may be 

seen everywhere in this city, all carved in figures and ani- 

mals, resembling the true coral, but on testing it with a 

knife, the baseness is easily detected. It is composed of 

marble powder, made into a paste by a very siccative oil 

or varnish, or soluble glass (silicate of potash), and a little 

isinglass, and colored by Chinese vermilion. The paste 

is then moulded into the various objects required, and when 

dry such parts as require it are perfected with the chisel. 

SHELL CAMEOS. 

The shells employed for cameo-cutting, .are the cassis 

rufa, and several species of cyprea, called cowries. They 

are dense, thick, and consist of three layers of differently 

colored shell material. In the cassis rufa, each layer is 

composed of many very thin plates, or lamina?, which are 

perpendicular to the plane of the main layer ; 

each lamina 

consists of a series of elongated prismatic cells, adherent by


their long sides ; the laminae of the outer and inner layers 

are parallel to the lines of growth, while those of the 

middle layer are at right angles to them. In cowries 

there is an additional layer, which is a duplicature of the 

nacreous layer, formed when the animal has attained its 

full growth. 

At the London Exhibition there was a very fine collec- 

tion of shell cameos, from Rome, owned by the engraver 

Seculine. 

Certain natives of India prepare shell cameos with rude 

but efficient instruments for cutting them, and the Indian 

department in the Exhibition showed numerous specimens. 

MOSAIC AND PIETRA DURA. 

Roman, Venetian, Florentine, and other Mosaics. 

The art of mosaic (opus musivum of the Romans), was origi- 

nally applied only to the combination of small dice-shaped 

stones (precious and common), or tessera? of the ancients, 

in patterns. 

It has long been an important source of labor 

to the inhabitants of several parts of Italy, such as Venice ; 

and under various modifications is now carried on in the 

principal cities of Europe. The manufacture has long 

ceased to be confined to combinations of tessera?, and is 

now understood to include all kinds of inlaid and veneered 

work, in whatever material, fragments of pseudo-precious 

stones (agate, chalcedony, malachite, lapis lazuli), marbles 

of the most variegated colors, porphyry, lava, granite, 

fluor-spar, and also the various colored glasses (imitation 

gems), avanturine, and enamels, which, when put together 

(sometimes in microscopical fragments), and formed into a 

landscape, figures, or other design, are now called mosaics. 

The richer the colors and shadings, so as to produce fine 

pictures, the more striking the mosaics fall on the eye of

MOSAIC AND PIETBA DURA. 427 

the spectator. The Roman mosaics, in which prisms or 

threads of glass, of various sizes and shapes, compose the 

whole picture ; 

the Venetian mosaics, where the glass is a 

tessera or square shape, of some size, inlaid often in a 

cement base. 

The manufacture of true Roman mosaics has always 

been confined to the city whence its name is taken, and no 

country has entered into competition with Rome. They 

are composed of glass, sometimes called smalt, and some- 

times paste ; are made of all kinds of colors and every 

different hue. For large pictures they take the form of 

small cakes ; for small works they are produced in threads, 

varying in thickness from that of a piece of string 

to the 

finest cotton thread : large quantities of these, of all tints 

and colors, are prepared. A plate or slab of copper, marble, 

or slate is then provided, of the size and thickness required 

for the intended work. This slab is hollowed out so as to 

resemble the bottom of a box or a tray, to a depth proportioned 

to the work; this may vary from an inch to the 

eighth, or even the sixteenth of an inch, if the work is to be 

small. This hollow is then filled with plaster of Paris, well 

smoothed, on which the outline of the proposed design is 

very accurately traced, and an inked pen is passed over 

the outline to preserve it. Very few tools are required by 

the workmen, but for the large works, where comparatively 

large pieces are to be inserted, small shape-cutting hammers 

are made use of for splitting the cakes and reducing 

them to their proper size and form ; pincers also, of differ-" 

ent forms, are used for placing them equally. In very 

small works, instead of hammers, sharp-pointed pincers are 

made use of, like those with which diamonds are taken up, 

and sometimes a small tool like a scarpello. The heat of 

an oil lamp is required, to enable the workman to draw out 

the strips of glass to the desired fineness, even to that of


a hair. When this is all ready, the first operation is to dig 

or scoop out, with a scarpello of a proper size, a small piece 

of plaster of Paris from the bottom of the box or tray, 

without injuring the outline ; this is filled up with a kind 

of mastic or putty, like that which is used for panes of 

glass in the sashes of a window ; 

and the required piece of 

smalt or glass is then pressed into the composition. In this 

way, step by step, and from day to day, repeating the 

operation of scooping out a small piece of plaster of Paris, 

and never losing sight of the outlines, they gradually fill 

up the whole tray. In works of considerable dimensions, 

the workmen place the tray before them as painters place 

the canvas on which they are painting, and have the original 

always close to them. For smaller works they sit at a 

table, as if writing, and keep the work flat on the same. 

The designs used in these mosaics are for the most part 

copied from the pictures of some artist of eminence, the 

designers themselves being also a separate body, working 

for the mosaicisti, who mechanically fill up the spaces as 

above described. When the operation is completed, it is 

passed over a stone made perfectly smooth and cleaned of 

every kind of dirt ; it happens, however, that interstices, 

however minute, will be left more or less between the 

several small pieces of smalt inserted into the mastic ; 

these 

are to be carefully filled up with heated wax, applied with 

hot iron instruments from a pallet on which it has been 

prepared for the purpose, and much of the good effect and 

finish of the work will depend on the ability and care of 

the workmen by whom this operation is performed. 

A most remarkable specimen of this beautiful art was 

shown at the London Exhibition, by the Cavaliere Barbed 

; it was a large round table, and represented cele- 

brated views in Italy; it was of singular delicacy and 

beauty of workmanship, the style of the design, the ex-

MOSAIC AND PIETRA DURA. 429 

quisite shading of the colors, the brilliant though softened 

effect of the group of views, the atmosphere and sky of each 

mingling into the same.ethereal tint, which relieved the eye 

and allowed it to rest with pleasure on the separate views : 

it was certainly a masterpiece. The author never left- the 

Crystal Palace without passing by the table, which always 

excited fresh admiration. 

There were two other mosaics, much larger than the 

former, and different in style, that were remarkably fine 

of a celebrated 

specimens of workmanship : one was a copy 

picture, by Guercino, a St. John the Baptist ; and the 

other a portrait of Pope Boniface the Second. 

A circular table, a square slab, and a picture representing 

a view of PaBstum, were likewise among the Roman 

mosaics in the London Exhibition. 

Dr. Chilton, of New York, has a beautiful Roman 

mosaic of the Pantheon, about three inches long. 

In the New York Exhibition, in 1853, the large picture 

of Pope Pio IX., in medallion size, was much ad- 

mired. 

In the Paris Exhibition, in 1855, many large works of 

Roman mosaics were exhibited ; 

one in particular, belonging 

to the Duke of Tuscany, required the constant work 

of fourteen years, and cost 700,000 francs. A large table 

in the rotunda of the panorama, of rich and elegant Roman 

mosaic, cost 400,000 francs. -^ 

The famous picture of the Campo-vacino, in Home, by 

Galand, cost the artist ten years' labor. 

Pietra dura, also called Florentine mosaic, consists in 

the manufacture of hard stone inlaid in a slab of marble ; 

they are, for the most part, of the quartz species, such as 

agates, jasper, chalcedony, carnelian, &c. ; also, lapis lazuli, 

malachite, and all such hard and colored minerals which, 

by their depth of color and brilliancy of lustre largely con-

430 A POPULAB TREATISE ON GEMS. 

tribute to produce a picture of a flower or a landscape, and 

all come under the name pietra dura of the Florentine 

school. 

In this kind of work, a slab of marble (generally black), 

of the required dimensions, and about one eighth to three 

sixteenths of an inch thick, is prepared, and the patterns to 

be inlaid are carefully cut out with a saw and file. The 

hard stones are worked into the required pattern by the 

ordinary methods of gem-cutting, and are accurately fitted 

into the spaces thus prepared, in a polished and finished 

state ; for if the whole were to be polished at once, some 

of the substances being softer than others, would be worn 

away too rapidly. The work, also, is liable to be spoiled 

by the accidental placing of one stone lower than another, 

and mistakes of this kind will often lead to the ruin of the 

whole. After the surface is thus prepared it is veneered 

on a thicker slab and is then fit for use. In point of diffi- 

culty of execution, durability, and taste, this process of 

inlaying in hard stones or gems may rank as the most important 

purely decorative work within the whole range of 

mineral manufactures. 

In order to illustrate the peculiar mode of inserting the 

different pieces of agate, jasper, &c., in these beautiful 

works of art, and to' show also to those not familiar- with 

them the elegant and simple forms produced, we give the 

following diagram, showing a fac-simile of a portion of 

the inlaid-work in one of the tables which were exhibited 

in the London World's Exhibition, in 1851. 

In this diagram the dark line represents the outline of 

the flowers, leaves, &c., and the dotted part, the lines 

where the different pieces forming a single object are 

joined together. The extreme delicacy and accuracy of 

the joints can only be fully appreciated by the examination 

of the original specimens.

MOSAIC AND PIETEA DUEA. 431 

Fig. 11. 

True Florentine mosaic, of fine design and good taste, 

was in profusion from Tuscany and St. Petersburg. 

A jewel-case belonging to the Empress" of Russia, was 

particularly worthy of notice : it was constructed of wood, 

having the four sides and top covered with groups of fruit 

cut in pietra dura, in a style which may be called cameomosaic 

in rather high relief; the stones were so selected as 

to afford perfect fac-similes, in color, size, and even in in- 

ternal structure, of the fruit they represented, which were 

currants, pears, and plums, and the whole work was ex- 

quisitely finished. 

The King of Sweden sent to the London Exhibition,


an inlaid oblong table of granite, porphyry, and jasper, 

of beautiful workmanship ; the materials were the hard 

stones of Sweden, which being nearly of equal hardness, 

admitted of being polished after the work Was finished. 

An Indian chess-table with an inlaid border, and a num- 

ber of small objects from India, the ground being a white 

marble of a peculiar saccharoidal texture, attracted great 

attention. The pattern was a fine scroll-work, remarkable 

for the extraordinary delicacy and exactness of the stems 

of flowers and the perfect joints 

the stems were of flint. 

This and another Indian inlaid-work are said to be of great 

antiquity. No comparison can be instituted between these 

Indian and 'European works, the mechanical execution of 

the former being at least equal to the best of those which 

have rendered Florence so justly celebrated, while the 

taste and design exhibited in them are greatly superior to 

inlaid work in marble. 

The great expense of inlaying hard- pebbles, which can 

only be cut as gems, and the excellent effect that may be 

produced by imitations in which marble of various kinds, 

shells, cement, and glass, replace the jasper and agate of 

Florentine mosaic, have caused the introduction into England, 

and elsewhere, of a manufacture which may be called 

inlaid marble work. In Derbyshire this branch of manu- 

facture has become very important. There are two prin- 

that followed 

cipal methods of producing marble mosaic ; 

in Derbyshire, where a recess is chiselled out of a solid 

block of marble, serving as the ground ; and that pursued in 

Devonshire, where the whole surface is in fact veneered; 

numerous marbles of various colors and forms being merely 

cemented together on a base, which may consist of slate, 

or any kind of marble; the whole surface being after- 

wards polished together. In Malta the former process is 

followed, while in Russia the malachite inlaid work is per-

MOSAIC AND PIETRA DURA. 433 

formed, as just described. The Duke of Devonshire loaned 

his fine collection of Florentine mosaics to the manufac- 

turers, from, which they copied the butterflies, leaves, and 

sprigs of jessamine, for which these mosaics are so celebrated. 

These works being used as guides, the art of inlaying 

was brought into successful operation, and materials 

foreign to the vicinity, as malachite from Russia, Continental 

marbles, Avanturine and other glasses, from Venice, 

with some cements, have been introduced into them. The 

manufacturers at Matlock, Ashford, Bakewell, Buxton, 

Derby, and Castleton are all doing a thriving business. 

A table with a wreath of flowers of extremely complicated 

pattern, and admirably finished, with a vast number 

of detached marbles, of Derbyshire work, owned by Mr. 

Yallance, attracted general attention at the "London Exhibition. 

Although not to be compared with the Florentine 

work, there were, nevertheless, much skill and labor bestowed 

upon it. 

A number of other tables of inlaid work, of the cinquecento 

style, were likewise weh 1 

executed. The exhibition 

of Derbyshire inlaid work was very large. 

A mosaic chess-table from the Isle of Man ; 

from Lisbon, 

interesting specimens of mosaic, composed of sixty specimens 

of Portuguese marbles ; and from the Cape of Good 

Hope, a peculiar kind of inlaid marble work, were at the 

London Exhibition, and all more or less interesting. 

Clay and Porcelain Mosaics* 

The encaustic and mosaic tiles used by the ancients for 

ornamenting houses, for pavements and walls, have of late 

years been extremely well imitated, both in England and 

the United States. 

The encaustic or inlaid tiles are made by pressing clay in 

in


the plastic state into an embossed plaster mould, the pattern 

or design on the mould being raised. When the tile is 

withdrawn from the mould, the outline of the pattern is 

indented, and the indented parts are filled in with colored 

liquid clays, according to the colors it is desirable to produce. 

The surface is then scraped quite flat, until the pat- 

tern appears well defined. The tile is then heated, or as it 

is termed, fired, which brings out the colors to the proper 

tint. 

The Venetian tiles and mosaics are produced by the com 

pression of powdered clays into metal dies, of any geometri- 

cal form that may be devised, the clays having been previ- 

stained with metallic colors. Each tile or tessera is, 

ously - 

of course, of the same color throughout. When fired, 

they are arranged on a smooth platform, with the faces 

downward, according to the design intended, after which 

liquid Roman or Portland cement is poured upon them, 

and they are thus formed into slabs of any size required. 

The Alhambra or Spanish tiles are made by pressing 

plastic clays into an embossed mould, which forms grooves 

or indentations these tiles are then ; 

fired, and come out of 

the oven with the pattern formed. The indentations are 

then filled in with enamels of various colors and fired again, 

which produces a brilliant efiect, and renders the tiles suit- 

able either for floors or the interior walls of buildings. 

A mosaic pavement, composed of tesserce of vitrified clay, 

of several colors and shapes, all produced by machinery 

with great rapidity, and without the necessity of chipping 

any of the tesserce, and at the same time making an endless 

variety of patterns, is produced in England, in the follow- 

ing manner : The clay being prepared in the usual way, 

by washing and sifting, and stained with various metallic 

oxides (oxide cobalt, blue smalts, manganese, zaffre, red 

lead, crocus mart-is, an rum musivum, oxide chrome, copper

MOSAIC AND PIETEA DTJBA. 435 

scales, &c., the principal ingredients used), is formed into 

thin ribbons, about three eighths of an inch thick and from 

three to four feet long, by a machine ; 

out of these ribbons 

the tessercB are cut by a patented machine, with great ra- 

pidity, and when dry are baked in saggers 

in the usual 

way. 

Pavement slabs are made by laying these tesserae face 

downwards on a perfectly flat slate, the pattern, of course, 

being reversed, and covering their backs with a layer of 

Portland cement, and two layers of rough thin tiles, care- 

fully embedded in the cement. In this way strong slabs are 

formed, of from an inch and three quarters to two inches 

thick, which are almost perfectly impervious to moisture or 

rising damp. 

The capitol extension, in the City of Washington, United 

States, is embellished with encaustic tiles ; and both the 

pavement in the halls of the house of representatives and 

senate chamber, and the avenues leading to them, and the 

encased walls, are laid out with bright-colored tiles, in the 

most gorgeous manner. 

Mosaic Tiles made with Soluble Glass. 

The many useful applications of soluble glass (which 

may be the silicate of soda, or the silicate of potash, or 

both alkalies combined with the silica), form a new era 

in the production of an artificial stone, which, if properly 

adapted, must ultimately supersede all other artificial 

stones or cements of any kind. If grains of sand, pebbles, 

lime, marble, or even granite, clay, and fluor-spar, are 

mixed with soluble glass into a paste of the consistency of 

putty, and this paste is then moulded into any required 

form, after slowly air-drying and burning the articles thus 

manufactured in a kiln at a bright-red heat, which may be


maintained for any length of time, by which process the 

alkali contained in the soluble glass is set free, the silica 

combines with the lime, and more particularly with the 

fluor-spar (fluoride of calcium), so durable a cement is 

formed thereby, that it will not admit of the smallest 

absorption of moisture, and consequently is absolutely unattackable 

by frost. By applying the chloride of calcium 

in solution to the cement, the supposed objection that the 

salts of soda, or alkali, are efflorescing by degrees, is hereby 

obviated, for the chloride of calcium at once absorbs the 

alkali. 

Soluble glass may be colored by various metallic oxides, 

so as to produce, when heated, very sharp colors, similar to 

enamels, and may also be employed for a coating over 

other paints, such as fresco, &c. 

As a cement for joining together heterogeneous and ho- 

mogeneous substances, it is unsurpassed, and when applied, 

renders the substances so coated both water and fire proof. 

If soluble glass is intended for a varnish, the proper specific 

gravity is 1'165, but for a paint it may be reduced to 

that of water. 

In France, soluble glass is much used in coating common 

building-stones, for the purpose of rendering them 

damp-proof. Marble buildings and damp cellars may be 

made impervious to dampness by varnishing the surface 

with soluble glass ; although the proper mode is to exhaust 

the air from the stone or brick, and then impregnate, it 

with soluble glass by pressure. A patent was lately taken 

out in England, for preserving building, pier, and wharf 

stones, by first coating them with a wash of chloride of calcium, 

and afterwards by the application of the concentrated 

solution of soluble glass, repeating the operation several 

times. Soluble glass was introduced into the United 

States, by the author of this work, in the year 1831, under

MOSAIC AND PIETEA DURA. 43} 

the authority of the government, for the purpose of pro- 

tecting the cannon and balls, exposed 

to the weather in 

the Brooklyn Navy Yard, against rust ; for this purpose, 

when treated with the various coloring pigments, such as 

oxide of manganese, umber, terra di sienna, ochre, Venetian 

red, ultramarine, &c., 

it is admirably adapted.

Q 

Chrsobtil 

-Jaspe 

tus(. Lapis 

stoiie Lazuli 

mrnam tmwm i 

1 

' 

Diamond 

Oriental OK "/: Or. 

Topaz, -ItnetfiYst Jlnbv Ckrvsoberfl 

- 

~~ - 

tiarnet Cinnninfini 

C 1[H 

Chciti-edonv 

(Itrxopnise ftridffte Chwsolite Opal 

a a 

TuriputHSf Malachite Amber 

IgM 

, 1 HHHI 

/>A.-,,y,x, /,dTO ^c Ltpidatitv .Varityan Serpentine 

Blood 

Hoc/use Labnada 

a 

Vurblt Porphrrr 

Granite 

E

EXPLANATION OF PLATES.

PLATE II. 

THE MOST REMAKKABLE EOTJGH DIAMONDS. 

No. 1. The Nizam, from India; it weighs 340 carats, is valued 

at five millions of francs, and belongs to the King of Golconda. 

No. 2. The great rough Diamond, as described by Tavernier, 

from India, weighing 282 carats. 

No. 3. The great South Star, from Brazil, weight when rough 

254i carats, was found in the mines of Begagem, in the province 

of Minas Geraes, in Brazil. It is as clear as water, slightly tinged 

with yellow ; it is valued at two and a half millions of francs ; it 

is thirty millimetres in height, forty in length, and twenty-seven 

in breadth. Its shape is a twelve-faced rhomboid, presenting 

altogether twenty-four triangles.

DIAMOND LATHE. 

PL.2.

fTfFjn 

-

THE. LARGE ROUGH DIAMONDS. 

PL.3

PLATE III. 

KEMABXABLE BOUGH DIAMONDS. 

No. 4. The great Spheroidal, six-sided, with forty-eight facets. 

" 5. The spheroidal Diamond, with twenty-four facets. 

" 6. A dodecahedral-pentagonal rough Diamond. 

" V. A dodecahedral-rhomboidal rough Diamond. 

" 8. An Octahedron, with twenty-four facets. 

" 9. An Octahedron, the primary form.

PLATE IY. 

REMAKKABLE BOUGH DIAMONDS. 

0i 10. A rough Brazilian Diamond. 

" 

12. A regular Tetrahedron. 

" 12. A round, concretional, rough Diamond, called Boort, 

" 

13. A rough Brazilian Diamond. 

" 14. A rough cubical Diamond. 

" 15. A rough Brazilian Diamond. 

" 16. A truncated octahedron Diamond. 

17. A rough Diamond, described by Tavernier. 

" is. A triangular crystal of Brazilian Diamond. 

" 19. An Octahedron, with modified secondary form.

ROUOH O/AMONOS 

PL.4

IUIIFBESI

ROUGH DIAMONDS 

PL. 6.

PLATE Y. 

No. 1. The improved Diamond Lathe (exhibited in the Paris 

Exhibition, 1855, by Phillippe). 

No. 2 and 2 a. The pincers, front and side view. 

THE PBINCIPLE OF CUTTING. 

No. 3. a. The table of a brilliant. &. The triangular faces. 

c. The angles terminating into planes, d. Lozenges 4 large and 

4 small, e. The planes on the edge of the stone. 

No. 3 a.f. The angles parallel with the planes, g. Pavilion 

or facets corresponding to Lozenges.* h. The collet of the bril- 

liant. 

No. 4. A rough Diamond, cleansed. 

" 5. Cut of the crown. 

" 5 a. The three different cuts. a. The table. 5. The girdle. 

c. The collet. 

No. 6. A Brilliant not recut. 

" 7. A Brilliant recut. 

8. Hose Diamond, a. The crown. 5. The facets. 

* Lozenge is the geometrical form of a rhomb.

PLATE VI. 

THE MOST CELEBRATED OUT DIAMONDS. 

No. 1. The Grand Mogul; it weighs 279 carats, and is valued 

at twelve millions of francs. 

No. 2. The Orlow, the great Russian Diamond, weighs 195 

carats, and is the size of a pigeon's egg : cost two millions of francs 

and a pension of one hundred thousand francs.* 

No. 3. The table Diamond of Ta vernier, weighing 242 carats. 

" 4. The Polar Star, weighing 40 carats. 

" 5. The Shah, belonging to the Russian crown, weighing 

95 carats. 

* It is on the top of the Russian sceptre, and has the form of a knob of a cane ; the 

under surface is a plane.

THE MOST CELEBRATED CUT DIAMONDS . 

PL. 6.

%> 

tnn 

B

6 

THE. MOST CELEBRATED CUT DIAMONDS 

7 

PL.T.

PLATE VII. 

THE OELKBEATED OUT DIAMONDS. 

No. 6. The Nassack, weighs 78| carats; was sold, in 1839, foi 

seven thousand six hundred pounds sterling, to the Marquis ol 

Westminster. 

No. 7. The great India half-cut Diamond, weighing 112 

carats. 

No. 8. A brillianted Rose in pear-shape, from India, weighing 

16 carats. 

No. 9. Another Rose in pear-shape, weighing 94^ carats. 

No. 10. A recut India Brilliant, weighing 29 carats. 

No. 11 and 11 a. The South Star of Halphen, weighing 124 

carats. 

No. 12 and 12 a. The Regent, or Pitt ; it weighs 136 carats, 

belongs to the French crown, is valued at five millions of francs, 

and is certainly the best-proportioned Diamond in the world ; it 

is perfectly pure and transparent, and sparkles with a magnificent 

play of color.

PLATE Till. 

THB CELEBRATED OUT DIAMONDS. 

No. 13. The Piggot, belonging to England, weighs 82 carats. 

No. 14. The Pacha of Egypt's Diamond, weighs 49 carats. 

No. 15. The Koh-i-noor, as it came from India ; and 15 a, its 

present form, from a side view. 

No. 16. An India pear-shaped Brilliant, weighing 31 1 carats. 

No. 17. A Half-Brilliant, faceted, weighing 14J carats. 

N"o. 18. Large Rose Diamond, of 280 carats. 

No. 19. An irregular Rose Piamond, in pear form, weighing 

20 carats. 

No. 20, An India Brilliant, described by Tavernier, weighing 

52 carats. 

No. 21 and 21 a. Large table Diamonds, step-cut.

THE. MOST CELEBRATED CUT DIAMONDS. PL. 8.

; 

^

THE. MOST CELEBRATED CUT DIAMONDS . 

22 

PL. 9.

PLATE IX. 

THE OELEBBATED OUT DIAMONDS. 

No. 22. The great Austrian Brilliant, belonging to the Grand 

Duke of Tuscany, weighing 139 carats ; valued at seven millions 

of dollars. 

No. 23. The Eugenie Diamond, belonging to the Empress ol 

France, weighing 51 carats. 

No. 24. The Hope Diamond, a beautiful blue Diamond, weigh- 

ing 44i carats. 

No. 25. A Brillolet of 16 carats. 

No. 26. A knob-shape of 10 carats. 

No. 27. A table-shape of 10 carats. 

No. 28. A flat Diamond of 20 carats. 

No. 29. A flat Diamond of 14 carats. 

No. 30 and 30 a. The celebrated Sancy, belonging to the 

French crown-jewels, weighing 33 carats, of pear-shape ; is 

valued at one million francs. 

No. 31. A large cleaved Diamond, of 64 carats, from India.

PLATE X. 

Ko. 1. Rock-Crystal Group, from Arkansas, IT. S. 

Size and weight of Diamonds, both round and square, from that 

of half a carat to 18^ carats.

PL.X.

PL.X/.

PLATE XI. 

AMEBICAN 

No. 1. California Marble. 

u 2. Verde Antique, from Vermont. 

3. Shell Marble, from New York. 

" 4. Tennessee Marble. 

" 5. Bale's Breccia Marble, from Lancaster, Pa. 

" 6. Potomac Marble. 

" 7. Variegated Marble, from the State of New York.

PLATE XII. 

No. 1. Black Marble, with petrified volutes (Pyramidella tur 

Unella). 

No. 2. Red, green, and white brecciated Marble, from Sicily. 

No. 3. Red mottled Marble, tertiary fresh-water Limestone, 

from Swabian Alps, cut parallel to the planes of the layers. 

No. 4. Pale, yellow, and violet Marble, from the Jura, in 

Wiirtemberg. 

No. 5. Reddish-yellow and bluish-red mottled Marble, from 

Wiirtemberg. 

No. 6. Marble, tertiary, cut perpendicularly to the planes oi 

the layers, from the Alps. 

No. 7. Pale-yellow Marble, and violet Flakes, from Wiirtem 

berg.

PL.XI/.

PLJfM.

PLATE XIII. 

No. 1. Tertiary brecciated Marble, from the Pyrenees. 

No. 2. Red Granite, consisting of red felspar, grey quartz, anc 

black mica, from Upper Egypt ; 

their monuments. 

used by the ancient Egyptians ir 

No. 3. Fibrous Calcite, or so-called Thermal Tufa, Sprude 1 

stein, from Carlsbad. 

No. 4. Compact Brown-spar, from Gibraltar. 

No. 6. Agate Marble, from Algiers.

PLATE XIY. 

No. 1. Kyanite, light-blue and oblique rhombic prism, with 

truncation, from St. Gothard. 

No. 2. Amphibole or dark-green Hornblende, Actinolite, an 

oblique rhombic prism, from Tyrol. 

No. 3. Precious Serpentine, in right rectangular prisms, from 

Norway. 

No. 4. Lumachelli or Fire Marble, containing fossil shells; the 

variegated colors are owing to nautilus or ammonite, from 

Corinthia. 

No. 5. Ruin Marble, cut perpendicularly to the planes of the 

layers, from Tuscany. 

-$o, g. Pea-stone, calcareous Stalactite, from the hot springs 

of Carlsbad. 

No. 7. Dark-brown ribbon Agate, Arabian Onyx, 

East Indies. 

No. 8. Pale-yellow Marble, 

from Florence. 

from the 

No. 9. Variegated Marble, containing Corals, from the transi- 

tion rocks of Nassau. 

No. 10. Bed brecciated Marble, from Italy. 

No. 11. Black Porphyry, from Sweden.

PLJ(/V.

PL.XV.

No. 1. Egyptian Jasper. 

PLATE XY. 

No. 2. Ribbon Jasper, striated with red and green, froir 

Siberia. 

No. 3. Pudding-stone or Quartz Conglomerate, from Scotland. 

No. 4. Horny-colored Agate, from the East Indies. 

from the East Indies. 

No. 5. Chrysolite, 

No. 6. Noble Garnet, Pyrope, from Bohemia. 

No. 7. Dark-yellow Topaz, burnt, and called Balais, from 

Brazil. 

No. 8. Granite, 

from Milan. 

No. 9. Wood Opal, a petrified pine, from Hungary. 

No. 10. Black ribbon Agate, from the East Indies. 

No. 11. Green Tourmaline (Brazilian Emerald) in Dolomite, 

from St. Gothard. 

No. 12. Moss Agate or Mocca-stone, from the East Indies. 

No. 13. Dark Topaz, from Brazil.

PLATE XVI. 

No. 1. Black and white mottled Marble, from the monotniE 

limestone of Ardennes. 

No. 2. Red antique Porphyry, from Upper Egypt. 

No. 3. Blue Copper, Azurite, from Germany. 

No. 4. Malachite, Green Copper, from Siberia. 

No. 5. Natrolite on Clinkstone, from Bavaria. 

No. 6. Clear-yellow Amber, inclosing several flies, from the 

coast of the Baltic, near Dantzic.

PL.W.

PLXVII.

PLATE XVII. 

No. 1. Dark-green Serpentine, from the Apennines. 

No. 2. Amazon-stone or apple-green Felspar, an obliqne rhom 

bic prism, from the Ural Mountains. 

No. 3. Fortification Agate, from Oberstein. 

No. 4. Green Porphyry Felspar, from Greece. 

No. 5. Serpentine, Ophicalite, or Verde de Corsica duro, from 

Corsica. 

No. 6. Labrador Felspar, from Labrador.

458 INDEX. 

Borax, double refraction of, 88; reagent, 

116. 

Botryoidal, 72. 

Brachydiagonal, 46. 

Brachydomes, 47. 

Brachypyramids, 47. 

Brazil, discovery of diamonds in, 1ST; 

revenue from diamonds in, 201. 

Brewsterline, 265. 

Brilliant, the, 161. 

Brillionets, 161. 

Bromine, 119. 

Bronzite, fusibility of, 116. 

Brown spar, 56. 

Burning of gems, 171. 

Cabochon cut, 165. 

0. 

Cachelong, an opal, 807. 

Cadmium, test of; 125. 

Cairngourm crystals, 261. 

Calamine, 55. 

Calc spar, 43, 65, 66, 70, 73 ; hardness, 78 ; 

double refraction, 86; varieties of, 364. 

Calcareous scheelite, refraction of, 88. 

Cameos, shell, 425. 

Cannel coal, described, 354. 

Carat, origin of the word, 181 ; weight of 

four grains, ib. 

Carbon, 120. 

Carbonate of soda, reagent, 116; refraction 

of carbonates, 87; electricity, 99. 

Carbuncle (see Spinelle), 228 ; garnet, 251. 

Carengeair's goniometer, 5S. 

Cornelian, hardness of, 80; described, 279. 

CatVeye quartz, described, 270. 

Caves, list of American, 880. 

Cerium, test of, 127. 

Chabasite, 56, 65. 

Chalcedony, 73; hardness of, SO; refraction 

of, 88 ; described, 277. Varieties 1, 

Chalcedonyx; 2, Mochastones; 3, Kainbow 

: 4, Cloudy ; 5, Plasma ; 6, Semicarnelian 

or ceregat ; 7, Sappharine ; 8, St 

Stephen's stones, 278; varieties of, 77. 

Chalcopyrite, 64. 

Chalk, 365. 

Chemical properties of minerals, 102 ; reac- 

tion, 113. 

Chlorine, 119. 

Chlorophane (a fluor spar), 335. 

Chromate of lead, refraction of, 87. 

Chromium, test of, 127. 

Chrysoberyl, degree of hardness, 80 ; real 

gem, 136; same as cyinophane, 225. 

Chrysolite (Peridote, olivin), nardness ot, 

80 real ; gem, 136 ; oriental, a sapphire, 

216; refraction of, 87; Ceylon, a tourmaline, 

256; described, 294. 

Chrysoprase, described, 292 ; value, 294. 

Cinnabar, refraction of, 88. 

innamon stone or Essonite, 253 ; see Hya- 

cinth de Ceylon. 

Cleaning gems, 172. 

Cleavage, varieties of; 76. 

Clinopinacoids, 51. 

Clinoprisms, 51. 

Clinopyramids, 51. 

American coal-fields, ib. 

Coal, 354 ; 

Cobalt, solution of, reagent, 117; test of, 

125. 

Cobaltine, 80, 31. 

Collet the, explained, 161. 

Colophonite, a garnet, 249. 

Color, change of, 93; table of colors of 

minerals, 96 of ; gems, 136. 

Combinations, 81. 

Conazeranite (felspar), 314. 

Copper, test of, 126. 

Coral, described, 419 ; 

varieties of red, 422. 

Cordierite, a real gem, 136. 

Corundum, hardness, 78 refraction ; 

of, 87 ; 

description of, 214; see Sapphire. 

Corundum, common, or Diamond spar, de- 

scribed, 223 ; granular, or emery, 224. 

Crown-jewels of France, value of; 207. 

Crown-jewels of Queen Victoria, 210. 

Cryptoiine, 265. 

Cryptocrystalline minerals, 73. 

Crystalline, 19. 

Crystallized, 19. 

Crystals, defined, 20 ; described, &. ; systems 

of, ib. ; imperfections of, 54 ; strise 

55 ; drusy, 56 ; measurement, 58 ; macles 

or tw4n crystals, 61 ; irregular aggrega- 

tion, 70. 

described, 827. 

Cyanite, 73 ; 

Cymophane (oriental chrysolites), refraction 

of, 87 see ; Chrysoberyl. 

D. 

Deltoid dodecahedrons, 28; sign, 80. 

Derivation of forms, 27. 

Diamond, 24, 25, 29; hardness of, 78, 80 i 

double refraction of, 87 ; first cut by Ca- 

radossa, 151 ; manner of cutting, 156, 183 ; 

polishing, 158 ; forms of, 161 ; discovery 

in a diamond lens, 182 ; general account 

of, 183, etc. ; pure carbon, 184; artificial, 

ib. ; form of crystals, 185 ; color, ib. ; the

compact, ib. ; the original bed of, 187: 

loss In cutting, 193; Hindoo division of. 

195; value, Vt. ; color, purity, ib.; de- 

gree of clearness, ib. ; cat and size, 196; 

prices of, 197-8; celebrated diamonds, 

154, 193, 203 ; the largest known, 208 ; in 

Victoria's crown, 211 ; 

Exhibition, 212. 

Diamond grinders, 155. 

at the Industrial 

Ditetragonal, pyramids, 36. 

Divelsteene, 156. 

Dodecahedrons, subdivided, 22. 

Dolomite, double refraction of, 87. 

Double facet cut, 165. 

Doublets, 180. 

Druses, 71. 

Drusy crystals, 56. 

Dyakisdodecahedron, 30; sign, 31. 

E. 

Edingtonate, double refraction of, SS. 

Electricity of minerals, 99. 

Electro-chemical elements, table of, 105. 

Electroscopes, 99. 

Elongated brilliant facet cut, 165. 

Emerald, hardness of, 80; double refrac- 

tion, 85; a real gem, 136; the oriental, a 

sapphire, 216; described, 235; emerald 

proper, ib.; how cut, 237; value, ib.; 

remarkable emeralds, 238 ; the Duke of 

Devonshire's, 239 ; the Brazilian, a tour- 

maline, 256. 

Emery, a common corundum, 224. 

Engraving on gems, 167. 

Essonite, or cinnamon-stone ; hardness of, 

80; real gem, 136, 250; described, 253. 

Euclase, double refraction of, 87; description 

of, 234. 

Facets, 161. 

.Fablore, 63. 

F. 

Felspar, 52, 53, 75; described, 312; common, 

315; ad ul aria. 312; march isonite. 

814; leclite or helleniaU, conazeranite. 

ib.; amazon-stone, 315; porphyry, 391 ; 

sienete, 893. 

Fish-eye (adularia), 31i 

INDEX. 459 

Fluor spar, crystalline forms, 23 24, 25, 56, 

63, 65, '70; hardness, 78, 80; ciouble re- 

fraction of, 88; electricity, 99; describ- 

ed, 333. 

Fluorine, test for, 120. 

Foil, use of, 169. 

Form, primary, 26 ; semi-tesseral, 28 ; parallel 

semi-tesseral, 30. 

Forms of crystalline aggregates, 71. 

Dimorphism, 110. 

Fortification agate, 284. 

Dioptase, double refraction of, 88. 

Fracture surfaces, 78. 

Disthene 

321. 

(Kyanite, sappare), described, Fusibility, test minerals as to, 115. 

Galena, 23, 24, 56, 63. 

G. 

Garlic, used in repairing gems, 170. 

Garnet, 23, 25, 27 ; hardness of, 80 ; double 

refraction of, 88 ; magnetic, 100 ; a real 

gem, 136 ; described, 247 ; varieties, 24S ; 

Syrian, Bohemian, Ceylonian, Aplome, 

ib.; precious or almandine, 24S ; coloph- 

onite, 249; allochroite, ib.; grossular, 

250; topazolite, ib.; melanite, pyrenaite, 

ouwarowite, ib.; the ancient car- 

buncle, 251. 

Gems, 135; enumerated, 136; color, gravity, 

and hardness of, ib.; chemical char- 

acter, 139; composition, ib.; artificial 

production, 140 ; geological character, 

145; geographical distribution, 140; division 

and nomenclature, 147; history 

of, 148; superstitions as to, 149; sculpture 

in, 151 ; grinding, 153 ; engraving, 

167; sawing and drilling, 168 ; polishing 

materials, ib.; heightening color of, 169 ; 

setting, 171; cleaning of, 172; imitations,^.; 

1, pastes, ib.; 2, doublets, ISO ; 

3, burning, 180; price of, 181; optical 

use of, 181. 

Girasol sapphire, 216 ; fire opal, 304 ; adu- 

laria, 313. 

Girdle, in diamonds, what? 161. 

Glucina, test of, 123. 

Goldstone, a paste, 278. 

Goniometers, 58. 

Goutte de sang, a spinelle, 228. 

Grand mogul diamond, 193, 203. 

Granite, described, 896; American varie- 

ties, 397. 

Gray copper ore, 28, 68. 

Grossular garnet, 250. 

Gypsum crystals, 51, 56, 68, 74; doable 

refraction of, 88 ; tntin gypsum, 341 ; al- 

abaster, ib.

460 

H. 

INDEX 

Haematite, 65. 

Hardness of minerals, 78 ; Mob's, scale of, 

ib.; rough scale, 79 ; of precious stones, 

80 ; of gems, 136. 

Hatchet-stone (jade), 361. 

Hausmanite, 64. 

Hauyne, described, 822. 

Heliotrope, described, 282. 

Hellefliata, or Leclite (felspar), 314. 

Helvine, 28. 

Hemihedric crystal, 21. 

Hetnimorphism, 54. 

Hemiorthotype system, 21. 

Hexagonal system, 21, 39; pyramids 40; 

dihexagonal, 41 ; rbombohedral, 42. 

Hexahedron, 22, 23 ; sign of, 27. 

Hexakisoctahedrons, 25 ; sign of, 27. 

Hexakistetrahedron, 28; sign, 30. 

Holland diamond, 206. 

Holobedric crystals, 21, 22. 

Hope diamond. 206. 

Hornblende, 68, 320. 

Hornstone, described, 277. 

ous property, ib. 

Hydroxide of iron, double refraction of, 88. 

Hypersthene, not hornblende, 820; de- 

scribed, ib. 

I. 

Iceland spar, 66 double ; 

refraction of, 86 ; 

described,. 364 

Icositetrahedrons, 22, 24 ; sign of, 27. 

Idocraso, double refraction of, 88 ; 

ed, 321. 

Ignoble metals, 101. 

Imitations of gems, 172. 

Indicolite (Brazilian sapphire), 256. 

Iodine, test for, 119. 

describ- 

lolite, real gem, 136; described, 297; di- 

chroite; peliom, lynx and water sapphire, 

298. 

Iridescence, 93. 

Iron, double refraction of, 88; test olj 

127. 

Iron pyrites, 30, 81, 55, 68. 

Irregular aggregation, 70. 

Isomorphic substances, 111. 

Isomorphism, 110. 

Itacolumite, diamond-bearing rock, 188. 

J. 

Jade (nephrite, hatchet-stone, punamu), 

described, 361. 

Jargon (see Zircon), 244 ; described, 246. 

Jaspachates, a variety of agate, 284 

Jasper described, 273 ; varieties : 1, Egyptian 

; 2, Ribbon spar, 276 ; jasper opal, 

308. 

Jet, hardness of, 80 ; described, 353 ; a bituminous 

coal, ib. 

Jewish tribes, gems allotted to, 149. 

Jeweller's wax, 172. 

Hyacinth, hardness of, 80; oriental, a sapphire, 

215; a variety of zircon, 246 ; described, 

247. 

Hyacinth de Ceylon (Essonite, or cinnainon-stone), 

258. 

Hyaline, 19. 

Hydrate of magnesia, double refraction 

of, 88. 

Hydrometer, 81. 

Hydrophane, a variety of opal, 305 ; curi- 

Kaolin, 75. 

Kneeshaped crystal, 64. 

Kohinoor, a celebrated diamond, 154; its 

loss in cutting, 193 ; history of, 208. 

Kuinur, a celebrated diamond, 154. 

Kyanite (sappare, disthene) described, 827. 

L. 

Labradorite, 70 ; not felspar, 317. 

Lamellar, 71. 

K. 

Lapidaries, ancient, 151; s6ciety of, 153; 

gem lapidary, 163; common, 164; his 

apparatus, ib. 

Lapis lazuli, or Armenian stone, described, 

322 ; uses of, 323. 

Lava described, 360. 

Lava, black glass lava, or obsidian, 310. 

Lazulite, hardness of, 80 ; azure-stone, 324 ; 

used to imitate lapis lazuli, ib. 

, 66 ; test of, 125. 

Leclite (felspar), 314. 

Lepidolite, described, 339. 

Leucite, 27. 

Lievrite, 48. 

Lithia, test of, 121. 

Lime, test of, 122. 

Lithographic stone, 366. 

Love's arrows, a rock crystal, 261. 

Lustre, 93 ; degrees of, 94 ; varieties of, ib 

Lyncurium, not tourmaline, 258.

M. 

Macles or twin crystals, 61. 

Macrodiagonal, 46. 

Macrodoines, 48. 

Macropinacoid, 48. 

Macroprisms, 48. 

Magnetic iron ore, 24, 63. 

Malachite, 74; hardness of, 80; describ- 

ed, 835; beautiful articles made of, 

338. 

Manganese, test of, 125. 

Marble (Carbonate of lime), described, 264; 

best localities, 366 ; ancient marbles, 367 : 

French, ib. ; English, 863; varieties of 

Derbyshire, ib. ; marble statuary, 370, 

876 ; American marbles, 871, 8S3 ; white, 

ib. ; ancrinital or bird's-eye, 372 ; mar- 

bles, &c., in N. Y. Geological cabinet, 

373 ; breccia, 375 ; serpentine or verd an- 

tique, ib. ; leocadia breccia, 876 ; Egyptian, 

382; Italian, ib. ; shell marble, 

885. 

Marcasite, 66 ; 

or pyrites, 390. 

Marekanite, brown obsidian, 310. 

Measurement of crystals, 58. 

Meerschaum, described, 857; uses of, 

358. 

Meionite, double refraction of, 888. 

Melanite, garnet, 250. 

Mellite, double refraction of, 88. 

Mercury, test of, 124 

Mica, double refraction of, 88 ; described, 

' 

889. 

Microcosmic salt, reagent, 116. 

Mineralogy, how limited in this work, 

16. 

Minerals, forms of, 19 ; crystalline, amorphous, 

ib. ; physical properties, 75 ; hardness 

and tenacity, 73 ; specific gravity of, 

SO; optical properties, 84; double re- 

fraction, 85; polarization of light, 89; 

pleochroism, 92 ; iridescence, 93 ; lustre, 

ib.; color, 95; phosphorescence, 98; 

magnetism, 100 ; smell, taste, touch, 101 ; 

chemical properties, 102; composition, 

ib. ; influence of chemical composition 

on external character, 109; chemical re- 

action, 113; fusibility, 114-; solubility, 

orders of, 134 

11T; classification, 129 ; 

Mispickel, 66. 

Mix facet cut, 164 

Mocha stones, chalcedony, 278. 

Mobs; his system of crystallization, 21; 

scale of hardness, 73. 

Molybdite, double refraction of, 88. 

IND EX. 461 

Monoclinochedric system, 21, 49 ; its forae, 

49; combinations, 51. 

Months, gems, allotted to, 149. 

Moonstone (Adularia), 318. * 

Moroxite, an oolite, 387. 

Mosaic, 426; Roman, 427; Florentine or 

pietra dura, 429; clay and porcelain, 

433. 

Murchisonite (felspar), 314' 

Nassak diamond, 198; its value, 200, 204, 

210. 

Natrolite, fusibility of, 115; described, 332. 

Naumann, his system of crystallization, 21. 

Nepheline, double refraction of, 88. 

Nephrite or jade, 361. 

Nicholson's hydrometer, 81. 

Nickel, magnetism of, 100; test of, 125. 

Nitric acid, test, 119. 

Nizam diamond, 208. 

Noble metals, 108. 

Non-metallic elements, 113. 

o. 

Obsidian, hardness of, 80; described, 809. 

Octahedron, 23; primary form, 26; how 

distinguished, ib. 

Ofigoclase, 69. 

Olivin, or Chrysolite, 294 

Ouwarowite, garnet, 250. 

Onyx, carnelian, 280 ; agate, 288 ; describ- 

ed, ib. ; cameos of, ib. 

Oolite, a calcareous spar, 365, 836. 

Oolitic crystals, 78. 

Opal, 73 ; hardness, 80 ; double refraction, 

88 ; iridescence, 93 ; described, 299 ; precious 

opal, ib. ; mother of opal, 801 ; celebrated 

specimens, 802; fire opal, or 

girasol, 304 ; common opal, 805 ; hydro- 

phanes, ib. ; semi-opal, 806 ; wood opal, 

ib. ; cachelong, 807 ; Jasper opal, 808 ; 

Ceylon or water opal, ib. 

Orders of minerals, 137. 

Oriental and occidental gems, 147. .'

462 I N DEX. 

P. 

Pastes and artificial gems, 172 ; receipts fo 

colored, 176 how ; detected, 179. 

Paunched diamonds, 195. 

Pavilion facets, 162, 164 

Pearls described, 400; how formed, ib. 

localities, 401; value of, 407; Unite 

States pearls, 409 ; artificial, 415. 

Peliom, a variety of iolite, 298. 

Pentagonal dodecahedron, 30; sign, ib. 

Pentagonal dodecahedron, and pentagona 

icositetrahedron, not observed in nature 

. 81. 

Peridote (see Sapphire, Chrysolite),216, 294 

Phosphates of lead and lime, double re 

fraction of, 88. 

Phosphate of lime, 388 ; its uses, ib. 

Phosphorescence, 98. 

Phosphoric acid, test of, 118. 

Phosphorite, 388. 

Pietra dura (Florentine mosaic), 429. 

Piggot diamond, 206. 

Pisolite (calcareous spar), 365, 386. 

Plasma, chalcedony, 278. 

Plaster of Paris ; a gypsum, 342; constitu- 

ents, ib. 

Platinum, test of, 126. 

Pleochroism, 92. 

Point diamonds, 161. 

Polar-star diamond, 206. 

Polarization of light, 89; instrument for 

observing, 90. 

Porodine, 19. 

Porphyry, a compact felspar, 391 ; 

can varieties, 392. 

Potassa, test of, 121. 

Prase, common quartz, described, 271. 

Prehnite, 56. 

Prismatic topaz, hardness, 78. 

Pseudomorphism, 74. 

Punamu (jade), 361. 

Ameri- 

Pyramidal system, 21. 

Pyrenaite, garnet, 250. 

Pyrites described, 390; also called Marca- 

site, ib. 

Pyrope, a garnet, 248. 

Q. 

Quartz cpmmon, Eose quartz, cats-eye, 

prase, avantnrine, 269. 

Quartz crystals, 55, 56; hardness, 78 ; double 

refraction of, 87, 88 ; an oxidized stone, 

184; a gem^ 136 ; described, 259. 

Queen Victoria's crown, 210. 

R. 

Rainbow chalcedony, 278. 

Bed silver, double refraction, 88. 

Eefraction, double, 85 ; 

table of, 87. 

Eegent diamond, 154, 193, 204. 

Eeniform crystals, 72. 

Ehombic system, 21, 45. 

Ehombic dodecahedron, 23 ; sign of, 27. 

Ebombohedral system, 21. 

Ehombohedron, 42 ; combinations, 44. 

Eibbon spar, 276. 

Eock of Gibraltar, carbonate of lime, 386 

Eock crystal, 78; hardness of, 80; de- 

scribed, 260; varieties, 261; specimens, 

262; water in them, 265. 

Eock salt, hardness, 78; double refrac- 

tion, 88. 

Rose diamond, 162. 

Rose manganese, described, 391. 

Rose quartz, 269. 

Eubellite, double refraction, 88; a real 

gem, 136 ; tourmaline, 255. 

Euby, hardness of, 80 ; a variety of sapphire, 

214, 215. 

Juby cat's-eye, 216. 

Euby spinelle, almandine, balais, varieties 

of spinelle, 227, 228. 

lussia, discovery of diamonds in, 189. 

~ûtil, double refraction of, 88. 

Saline ores, 134. 

aline stones, 134. 

s. 

ancy diamond, 204 ; history of, ib. 

iappare (kyanite, disthene), described, 327. 

appharine, a chalcedony, 278. 

sapphire, hardness of, 80 ; iridescence of, 

93 ; real gem, 136 ; synonymous with 

corundum, 214 ; description of, ib.; va- 

rieties, 215; ruby, oriental hyacinth, 

amethyst, sapphire, and topaz, 215; 

aquamarine, chrysolite, and emerald, 

216; its constituents, 216; locality, 217; 

mode of cutting, ib.; uses, 219 ; value, 

ib. ; remarkable sapphires, 221, 222 ; 

Brazilian sapphire or indicolite, a tour- 

maline, 256 ; lynx and water sapphire, 

iolites, 298. 

arda, ancient name for Carnelian, 279. 

ardonyx, a carnelian, 280; agate, 289' 

cameos and intaglios, 290. 

atin gypsum, described, 341. 

atin spar, described, 340. 

calenohedron, 43.

Scapolite, 79. 

Schlaggenwald fluor spar, 70. 

Schorl, electric, a tourmaline, 256; origin 

of the name, 258. 

Sculptors in gems, 152. 

Selenium, test for, 118. 

a chalcedony, 1b. 

Semi-camel ian, 278 ; 

Semi-tesseral forms, 28. 

Serpentine, described, 362. 

Setting of gems, 171. 

Shah diamond, 206. 

Shrugging in diamonds, 195. 

Siberite, a tourmaline, 255. 

Siderite, 56. 

Sienite (felspar and hornblende), 893; 

American varieties, 894. 

Signs, crystallographic, 27. 

Silver, test of, 126. 

Soda, test of, 121. 

Solubility, .17 

Soluble glass, 435. 

Somerviilite, double retraction of, 88. 

South star diamond, 193, 210. 

Specific gravity of minerals, 80 ; how as- 

certained, ib,; of gems, 136. 

Spinel, spinelle, 23, 63; hardness, 80; 

double refraction, 87; real gem, 136; 

described, 227; constituents, ib.; varie 

ties, 227, 223; ruby spinelle, ruby balais, 

almandine ruby, goutte de sang, ib.; im- 

itation, 229. 

Stalactite, 73, '365; described, 380. 

Stalagmite, 73 ; described, 380. 

Star facets, 162. 

Star of the south, 210. 

Staurolite, 66. 

Stephanite, 66. 

Stilbite, 48, 56. 

Strahlstein, fusibility of, 115. 

Striae, 55. 

Strontia, test of, 122. 

St Stephen's stone (chalcedony), 278. 

Stygmite, a carnelian, 281. 

Sulphate of baryta, 87. 

T. 

Table of a diamond, 161. 

Table diamond, 163. 

Talc, hardness of, IS. 

Tantalium, test ot, 128. 

INDEX. 463 

Tchingtching (lapis lazuli). 325. 

Tellurium, test ot, 124. 

Tenacity of minerals, 80. 

Terminology, 19. 

Tesseral, or tessular system, 21 ; described, 

82. 

Tetragonal system, 21, 34; closed forms, 

35 ; tetragonal pyramids, ib.; ditetragonal, 

ib.; tetragonal sphenoids, 36; tet- 

ragonal scalenohedrons, ib.; open forms, 

86 ; tetragonal prisms, ib. 

Tetragonal crystals, how distinguished, 87. 

Tetrahedral form, 28 ; its sign, 29. 

Tetrakishexahedrons, 24 ; sign ot, 27. 

Thorina, test of, 123. 

Thumerstone, or axinite, 31L 

Tin, test of, 125 tin ; ore, 64. 

Titanium, test of, 129. 

Topaz, crystal, 48; hardness, 80; optical 

power, 87; electric, 99; a real gem, 

136; description of, 229; varieties, 230 ; 

cutting of, 231; localities, 232; imita- 

tions, 233; engraved topazes, ib.; topaz 

of the ancients, 229, 234. 

Topazolite, 250. 

Tourmaline, 55, 56; double refraction oft 

88; polarization of light, 89; real gem, 

136; described,- 254; composition of, 

255; 1. Siberian (siberite, rubellite, apyrite), 

ib.; 2. Indicolite (Brazilian sapphire); 

S.Brazilian (emerald); 4. Ceylon 

(chrysolite) ; 5. Electric schorl, 256 ; lo- 

calities, ib.; fine, specimens, ib.; not lyncurium 

of the ancients, 258. 

Triakisoctahedron, sign o^ 27. 

Triclinohedrie system, 21, 52; pyramids, 

53 ; combinations, ib. 

Trigonal dodecahedrons, 28 ; sign, 29. 

Tufa, calcareous spar, 365. 

Tungsten, test of, 128; see Wolfram. 

Turquoise, hardness of, 80 ; described, 329 ; 

1. true oriental; 2. bone, or occiden- 

tal, 330. 

Sulphur, 48; refraction of, fc7 ; test for, 118. 

u. 

Sunstone, sapphire, 216; iridescence of, 

93; adnlaria, 313. 

Ultramarine, made from lapis lazuli, 324; 

Systems of crystals, 21. 

how prepared, 325; imitations, 826. 

Uranium, test ot; 128. 

Y. 

Vanadium, test of, 128. 

Variolite (felspar), 814. 

Venus' hair, 261. 

Volcanic glass, or obsidian, 80fc

4G4 

W. 

INDEX. 

Water in rock crystal, analysis of, 265. 

Weiss and Rose, system of crystalliza- 

Yttria, test of, 128. 

tion, 21. 

Wernerite, double refraction o 88. 

Wolfram, 68; test of, 120; see Tungsten. 

Wollaston's goniometer, 58. 

z. 

Zircon, 

123; described, 244; same as hyacinth 

uroodstone, 2TT. 

ib.; varieties, 245. 

Zuisang (lapis lasuli), 825. 

Zinc, blend, 64 test of 124. 

; 

double refraction of, 87; test of

APPENDIX. 

CHRONOLOGICAL LIST 

OF 

WORKS ON GEMS AND MINERALS 

SINCE THE FIFTEENTH CENTUBY. 

BECHAI, (Ben Ascliar,) Biur al Hattorah, (Exposition of the Law of 

Moses,) a Commentary on Exodus xxviii. 17-20* A. M. 5207, 

(A. D. 1447.*) 

Plinii secundi, (Caii,) Naturalis Historia. Fol. Venice, 1469. 

Aristotle, Lapidarius, de novo e Graeco translatus. Lucas Brandis. 

4to. Eegia Mer&ourg, 1473. 

Serapion, (John,) De Medicamentis tarn simplicibus quam compositis. 

Mediolanum, 1473. 

Alberti, (Magni,) Philosophorum maximi de Mineralibus. Libri V. 

Patavii, 1476. 

Avicenna, (Abou-Ali-Alhussein-Ben-Adloulah,) Canones Medicinae, 

Latt. reddit. Venice, 1483. 

Csesalpinus, (Andreas,) De Metallicjs Libri tres. 4to. Rom. 1496. 

Leonardus, (Camillus, M. D.,) Speculum Lapidum. 4to. Venet. 

1502. 

* This work contains an ample account of the properties of precious stones. 

The edition of 1447 is the earliest, but it has since been many times re- 

printed.

466 APPENDIX. 

Aben Ezra, (Rabbi,) Commentarium in Decalogum. 8vp. Hehr. 

Basel, 1527. 

Rue, (Franc, de la,) De Gemmis. 8vo. Parisii, 1547 ; 8vo. Lugd. 

1622 ; 12mo. Franc. 1626 ; 12mo. Gron. 1626. 

Agricola, (G.,) De Re Metallica, Libri XI. ; et de Natura fossijium, 

Libri X. Fol. BasUice, 1546. 

Ruens, (F.,) De Gemmis aliquot, iis prsesertim quarum Divus Joannes 

Apostolus in sua Apocalypsi notavit. 8vo. Paris, 1547. 

Libravii (Andr.,) Singularium libr. IV. quorum I. et III. de metallis 

lapidibus, et fossilibus. 8vo. Franco/. 1549 ; also in 1601. 

Encelius, (Christoph,) De Re Metallica, hoc est, de origine, varietate 

et natura corporum metallicorum, Lapidum, Geinmarum atque 

aliarum quae ex fodinis eruuntur Libri III. 8vo. Francf. 1551. 

Theophrasti, (Eresii,) Opera omnia, Greece, cura Camotii edidit F. 

Turisanus. 70. Venetus, apud Aldi filios, 1552. 

Langius, (Johannes,) Epistolse Medicinales. Fol. Lugd. 1557. 

Agricola, (George,) De Ortu et Causis Subterraneorum. De Natura 

eorum quse effluunt ex Terra. Fol. Bas. 1558. 

Mandeville, (John,) Le Grand Lapidaire, ou sont declarez les noms 

de Pierres orientales, avec les Vertus et Proprietes d'icelles, et iles 

et pays ou elles croissent. 12mo. Paris, 1561. 

Porta, (Giov. Baptista,) Magiae Naturalis Libri IV. Antwerp, 1561. 

Fallopius, (G.,) De Medicatis Aquis atque de Fossilibus, tractatus ab 

Andrea Marcolino collectus. 4to. Venitia, *1564. 

Dolce, (Ludovico,) Libri tre, nei quali si tratta delle diverse sorti 

delle Gemme che produce la Natura. 8vo. Yen. 1564. 

Rulandus, (Martinus,) Medicina Practica, 12mo. Arg. 1564. 

Gesneri, (C.,) De omni rerum fossilium genere, gemmis lapidibus, 

metallis, &c. 8vo. Tiguri, 1565. 

Leonardus, (Camillus;) Trattato delle Gemme che produce la Natu- 

ra ; traduzione di M. Ludovico Dobe. 8vo. 1565. 

Gesner, (Conrad,) Liber de Rerum fossilium, Lapidum, et Gemmarum, 

maxime figuris, etc. 8vo. Tig. 1565. 

Epiphanius, De duodecim Gemmis in Veste Aaronis. Gr. Lat. cum 

corollario Gesneri. 8vo. Tig. 1565. 

Fabricius, (G.,) De metallicis rebus et nominibus obs. var. erud 

quibus. ea potissimum explicantur quse G. Agricola praeteriit. 8vo. 

Tiguri, 1566. 

Lemnius, (Levinus,) Occulta Naturae Miracula. 8vo. Antwerp, 1567. 

Mizaldus, (Anton.,) Memorabilium Utilium et Jucundorum Centuria 

IX. 8vo.

V 'APPENDIX. 467 

Cellini, (Benvenuto,) Del Arte del Gioiellare. 4to. Fior. 1568. 

Albert!, (Magni,) De Mineralibus et rebus metallicis. Libri V. 8vo. 

1541, 1569. 

Mizaldus, (Anton.,) Secrets de la Lune. Svo. Paris, 1571. 

Athenaeus, Deiphnosophistae, (Banquet des Pliilosopb.es,) traduit par 

Dalecbamp. Paris, 1573. 

Marbodaaus, (Gallus,) De Gemmarum Lapiduinque pretiosorum formis 

atque viribus opusculum. 8vo. Colon. 1593 ; 12mo. Ba#. 

1555 ; 12mo. Lubec, 1575. 

Belleau, (Rene,) Les Amours et nouveaux Changes des Pierres pre 

cieuses. 4to. Paris, 1576. 

Evax, (a King of the Arabs,) a MS. is attributed to him on the 

properties and effects of precious stones, published by Henry 

Rantzovius, under the title " De Gemmis scriptum olim a poeta 

quodam non infeliciter carmine redditum et nunc primum in lucem 

editum." 4to. Leipsic, 1585. 

Bacci, (Andrea,) Le XII. Pietre preziose. 

' 

4to. Roma, 1587. 

Cnesalpin, (A.,) De re metallica. 4to. Romce, 1596. 

Porta, (Giov. Baptista,) A Method of Knowing the Inward Virtues 

of Kings by Inspection. Fol. Neapoli, 1601. 

Arnobio, (Cleandre,) II Tesoro delle Gioie, trattato maraviglioso. 

Venet. 1602. ^ 

Bacci, (Andrea,) De Gemmis et Lapidibus pretiosis, tractatus ex Ital. 

Lingua Lat. red. 8vo. Franco/, 1605. 

Fernel, (John Francis^) Pharmacia, cum Guliel. Plantii et Franc. 

Saguyerii Scholiis. 12mo. Hanov. 1605. 

Morales, (Gasp, de,) Libro de las Virtudes y Propriedades maravil- 

losas de las Piedras preziosas. 8vo. Madrid, 1605. 

Porta, (Giov. Baptista,) De DistiUationibus. 4to. Rome, 1608. 

Avicennaa Opera. Roma?, 1593. Venetiis, 1608. 

Ferrante Imperator : De fossilibus opusculum. 4to. Napoli, 1610. 

Portaleone, (Abraham,) Shilte Haggeborim. (The Shields of the 

Mighty.) Heb. Mantua, (A. M. 5372,) 1612. 

Clutius, (Augerius,) Calsvee, sive Dissertatio Lapidis Xephrititri, seu 

Jaspidis viridis, naturam, proprfetates, et operationes exhibens 

Belgice. 8vo. Amsterdam, 1621, et Lat. per Gul. Lauremberg, 

fil. 8vo. Rostochii, 1627. 

Bacci, (Andrea,) De Gemmis ac Lapidibus pretiosis in S. Scriptura. 

4to. Rome, 1577 ; 8vo. Franc. 1628. 

Jonstonus, (Johannes,) Thaumatographia Naturalis. 12mo. Amst. 

1632,

468 APPENDIX.* * 

Clave, (Estienne,) Paradoxes, ou Traittez PMlosopliiques desPierres 

et Pierreries, centre 1'opinion vulgaire. 8vo. Paris, 1635. 

Csesius, (Bernardus,) De Mineralibus. Fol. Lugduni, 1636. 

Toll, (Adrianus,) Gemmarum. et Lapidum Historia. 8vo. Lugduni, 

1636. 

Boot, (Anselmus Boetius de,) Gemmarum et Lapidum Historia. 4to. 

Hanover, 1690. Recensuit et commentariis illustravit Adr. Toll. 

8vo. Lugd, Batav. 1636. 

Boot, (Ans. Boe'ce de,) Le Parfaict Joaillier, ou Histoire des Pierreries, 

de nouveau enriclii de belles Annotations par Andre Toll, trad, du 

Lat. par J. Bachou. 8vo. Lyon, 1644. 

Toll, (Adr anus,) Le Parfaict Joiillier, ou Histoire des Pierreries, ou 

1 01 1 amplement descrites leur naissance, juste prix, 

Lyon, 1644. 

etc. 8vo. 

Laet, (Jo. de,) De Gemmis et Lapidibus, Lib. II. Gr. et Lat. Part*, 

1647. 

Ecchellensis, (Abraham,) Versio Durrhamani de Medicis Virtutibus 

animalium, plantarum et Gemmarum. 8vo. Pans, 1647. 

Habdarralimanus, (Asiutensis ^Bgyptius,) De Proprietatibus ac Virtutibus 

medicis Animalium, Plantarum ac Gemmarum, ex Arab. 

Lat. redd, ab Abrahamo Ecchellenst 8vo. Paris, 1647. 

Laet, (John de,) De Gemmis et Lapidibus Libri II., quibus prsemit- 

de Lapidibus Gr. Lat., cum Annotationi- 

titur Theophrasti Liber ; 

- bus. 8vo. Ludg. Bat. 1647. 

Boetius, (de Boot,) Gemmarum et Lapidum historia, quam olim 

edidit Ans. B. de Boot, postea Adrianus Tollins recensuit. Tertia 

Edit, longe purgatissima. Cui accedunt Jo. de Laet, de gemmis 

et lapidibus Libri II., et Theophrasti liber de Lapidibus. 8vo. 

Lugduni Batawrum, 1647. 

Paracelsus, (Philippus Aurelius Theophrastus,) Nine Books on the 

Nature of Things ; into English by J. F. 4to. London, 1650. 

Nichols, (Thomas,) Arcula Gemmea ; or, the Nature, Virtue and 

Valour of Precious Stones, with Cautions for those who deal in 

them. 4to. Cambridge, 1652. 

Nichols, (Thomas,) A Lapidary, Vr History of Pretious Stones ; 

with 

Cautions for the undeceiving of all those that deal with Pretious 

Stones. 4to. Cambridge, 1652. 

Hermes Trismegistus, Tabula Smaragdina vindicata. 12mo. 1657. 

Nichols, (Thomas,) Gemmarius Fidelis, or the Faithful Lapidary ; 

experimentally describing the richest Treasures of Nature, in an 

Historical Narrative of the several Natures, Virtues and Qualities

APPENDIX. 469 

of all Precious Stones, "with a Discovery of all such as are Adul- 

terate and Counterfeit. 4to. London, 1659. 

Lowell, (Robert,) Panzoologicomineralogia, or a History of Animals 

and Minerals. 12mo. Oxford, 1661. 

Johnson, (J.,) Notitia regni mineralis, sive Catalogus subterraneorum 

cum prsecipuis differentiis. 12mo. Lipsice, 1661. 

Berquen, (Robert de,) Les Merveilles des Indes Orientales et Occi- 

dentales, ou nouveau Traite des Pierres precieuses et des Perles. 

4to. Pflrw,.1661. 

Jonstonus, (J.,) Notitia Regni Yegetabilis et Mineralifl. 12mo. Lips. 

1661. 

Boyle, (Hon. Robert,) Experiments and Considerations upon Colour, 

with Considerations on a Diamond that Shines in the Dark. 8vo. 

London, 1663. 

Kircheri, (Athanasii,) Mundus subterraneus in Libros XII., digestus. 

With plates and portraits of Kircher and Pope Alexander. 

. Amsterdam, 1665. 

Fol. 

Histoire des Joyaux et des principales Richesses de 1'Orient et de 

1'Occideat. 12mo. Geneve, 1665. 

M. L. M. D. S. D., Denombrement, FacultS et Origine des Pierres 

precieuses. Post 8vo. Paris, 1667. 

Schmid, (Joachimus,) De Margaritis. 4to. Wtttebergce, 1667. 

Rhosnel, Le Mercure Indien. Paris, 1668. 

Piererus, (G. P.,) Lazulus, Dissertatio chymico-medica. 4to. Ar- 

gentarati, 1688. 

Aldrovandi, (Ulyssis,) Opera Omnia. 3 vols. fol. with several thousand 

wood cuts. B&nonice, 1599-1668. 

Tesoro deUe Gioie, Trattato Curioso. 12mo. Venetia, 1670. 

History of Jewels. 12mo. London, 1671. 

Steno, (Nicolaus,) Prodromus to a Dissertation concerning Solids 

naturally contained within Solids. London, 1671. 

Boyle, (Hon. Robert,) An Essay about the Origin and Virtues of 

Gems, with some Conjectures about the Consistence of the Matter 

of Precious Stones, etc. London, 8vo. 1672, and 12mo. 1673. 

Sandius, (Christopher,)* On the Origin of Pearls. Phil. Trans. 

1674. 

Tavernier, Voyages en Turquie, enj'erse et aux Indes. 4to. Paris, 

1676. 

Kircher, (Athanasius,) Mundus Subterraneus in XII. Libros digestus. 

Fol. Ainstellodami, 1678. 

Blumenberg, Dissertatio Medica de Succino. 4to. Jena, 1682.

470 

APPENDIX. 

Kirani, Kiranedes, et ad eas Rhyakini Koronides, sive Hysteria 

Physico-Medica. 12mo.. London, 1685. 

Konig, (Emanuel,) Regnum Minerale, physice, inedice, anatomice, 

alcliymice, analogice, tlieoretice et practice investigatum. 4to. 

Basil, 1687. 

Orpheus, (1260 B. C.,) Hymni et de Lapidibus, Gr. Lat., curante A. 

C. Eschenbachio ; accedunt H. Stepliani notae. 8vo. Traj. ad Rh. 

1689. 

Panthot, (Jean B.,) Trait e des Dragons et des Escarbqucles. Small 

12mo: Lyon, 1691. 

Hiaerne, (Urban,) Kort Anledning til askillige Malm och Bergarters, 

Mineraliers, etc. ; eftersporjande och angifvande. Stockholm, 1694. 

Hiller, (Matth.,) Tractatus de Gemmis XII. in Pectorali Pontificis 

Hebraeorum. 4to. Tubingen, 1698. 

Slevogtii, (J. H.,) De Lapide Bezoar. 4to. Jena, 1698. 

Venette, (Nicolas,) Trait6 des Pierres. 12mo. Amst. 1701. 

Strachan, Observations on Coral, large Oysters, Rubies, etc. Abr^ 

ii. 711. Phil. Trans. 1701. 

Gulielmini, De Salibus dissertatio physica, medico-mechanica. Ve- 

netiis, 1705. 

Curiose Speculationen. Leipzig, 1707. 

of the Diamond. Phil. Trans. Abr. ii. 405. 1708. 

Description 

Chambon, 

1714. 

Traite des Metaux et des Mineraux. 12mo. Paris, 

Leisnerus, (Gott. Christ.,) De Coralliorum Natura, Proeparatis et 

Usibus. Wittembergw, 1720. 

Cappeller, (Maur. Ant.,) Prodomus Crystallographise, de Crystallis 

iinproprie sic dictis Commentarium. 4to. Lucernce, 1723. 

Henckel, (J. Fr.,) Pyritologia. 8vo. Lip&im, 1725. 

Woodward, (Dr. J.,) Fossils of all kinds digested into a method suitable 

to their mutual relation and affinity. With plates. London, 

1728. 

Woodward, (Dr. J.,) An attempt towards the Natural History of the 

Fossils of England, in the collection of J. Woodward. 8vo. Lon- 

don, 1729. 

Memoires de Regne de Catherine, Imperatrice de Russie. Amster- 

dam, 1729. 

Bourget, Lettres sur la Formation des Sels et Cristaux. 12mo. 

% Amst. 1729. 

Bromel, (Magn. von,) Inledning til nodig Kundskap om Bergarter, 

Mineralier, Metaller, samt Fossil ier. 8vo. Stockholm, 1730.

APPENDIX. 471 

Gimma," (D. Giacinto,) Delia Storia naturale dell^ Gemme, delle 

Pietre e di tutti Mineral!, owero della Fisica sotteranea. 4to. 

Napoli, 1730. 

Sarmento, (James Castro de, M. D.,) An Account of Diamonds found 

in Brazil. Phil. Trans. Abr. vii. 503. 1731. 

Henckel, (J. Fr.,) Idea generalis de Lapidum origine. 8vo. Dresd. 

et Lips. 1734. 

Colonne, (Francois Marie Pompee,) Histoire Naturelle de TUnivers. 

4 vols. 8vo. Paris, 1734. 

Pluche, (1'Abbe Antoine Noel de,) Spectacle de la Nature. 4to. 

Paris, 1732-39. 

Becher, (John Joachim,) Physica Subterranea. 4to. Lipsice, 1739. 

Argenville, Traite de 1'Oryctologie. Paris, 1740. 

Marbodaeus, De Lapidibus pretiosis Enchiridion, cum Scholiis Pic- 

torii. 4to. Wolfenbuttelce, 1740. 

Swedenborgii, (Emanuelis,) Opera Philosophica et Mineralia. 3 

vols. fol., with numerous plates. Paris, 1743. 

Argenville, (A. J. D. d',) De 1'Histoire Naturelle eclaircie dans deux 

de ses parties principales : la Lithologie et la Conchologie. 4to. 

Paris, 1743. 

Elliott, (John, F. R. S.,) on the Specific Gravity of Diamonds.' Phtt. 

Trans. Abr. ix. 147. 1745. 

St. Laurent, (Joanon de,) Description abregee du fameux Cabinet de 

M. le Chevalier de Baillon, pour servir a 1'histoire naturelle des 

Pierres precieuses, etc. Luques, 1746. 

Theophrastus, History of Stones, with the Greek Text and an English 

Version, and Notes Critical and Philosophical, including the 

Modern History of Gems described by that Author, by Sir John 

Hill. 8vo. London, m$. 

Kahler, (Mart.,) De Crystallorum Generatione. 4to. Upsal,174X. 

Henckel, (J. Fr.,) In Mineralogia redivivus. 8vo. Dresdw, 1747. 

Wallerius, (J. G.,) Mineralogia eller Mineral Ricket indelt och beskrifvet. 

8vo. Stockholm, 1747. 

Dingley, (Robert, Esq.,) On Gems and Precious Stones, particularly 

such as the Ancients used to engrave on. Phil. Trans. Abr. ix. 

345. 1747. 

Hill, (Sir 'John,) The History of Fossils. London, 1748. 

Leonardus, (Camillus,) The Mirror of Stones, in which the Nature, 

Generative Properties, Virtues and Various Species of more than 

200 different Jewels, Precious and Rare Stones are distinctly 

described. 8vo. London, 1750.

472 APPENDIX. 

Mariette, (P. J.^ Trait6 des Pierres gravies. Fol. Paris, 1750. 

Jeffries, (David, Jeweller,) Treatise on Diamonds and Pearls, in which 

their importance is considered, plain rules are exhibited for ascertaining 

the value of both, and the true method of manufacturing 

Diamonds is laid down. 8vo. 30 copper plates. Published by 

subscription. London, 1750-51 and 1753. 

Jeffries, (D.,) Trait6 des Diamants et des Perles. 8vo. . Paris, 1753. 

Pott, (M. J.,) Lithogeognosie, ou Examen chymique des Pierres et 

des Terres en general et de la Topaze et de la Steatite en particu- 

lier. 8vo. Paris, 1753. 

Jeffries, (David,) An Abstract of the Treatise on Diamonds and 

Pearls, by which the usefulness to all who are any way interested 

in these jewels will sufficiently appear, and therefore addressed to 

the nobility and gentry of this kingdom, and to the traders in 

jewels. 8vo. Baldwn, London, 1754. 

Natter, (Laurentius,) A Treatise on the Ancient Method of Engraving 

Precious Stones compared with the Modern. Fol. London, 

1754. 

Traite des Pierres _de Theophraste, trad, du Grec. 12mo. Paris, 

1754. 

Salerne, L'Oryctologie. 4to. Paris, 1755. 

Cartheuser, Elementa Mineralogise systematice disposita. 8vo. Fran- 

co/. 1755. 

Kalm, (P.,) Nagra Kannemarken til nyttiga Mineraliens eller ford 

och Baigarters upfinnande. 4to. Aboce, 1756. 

Da Costa, (E. Mendes,) Natural History of Fossils. 4to. London, 

1757. 

Pott, (J. H.,) Chemische tlntersuchungen, welche vornehmlich von 

der Litheognosie handeln. 4to. Potsdam, 1746 ; also 1751-54 

and 1757. 

Woltersdorf, (J. L.,) Systema minerale in quo regni mineralis producta 

omnia systematica per classes, ordines, genera, et species 

proponuntur. 4to. Berlin, 1738 ; also 1753-4, and 1755-8. 

Cronstedt, (Axel von,) Forsok til Mineralogia eller Mineral-rikets Upstallning. 

8vo. Stockholm, 1758. 

Bomare, (Valmont de,) Prospectus d'un cours surl'histoire.Naturelle 

des Mineraux. 12mo. Paris, 1759. 

Gerhard, (C. A.,) Disquisitio physico-chemica Granatorum Silesiae 

atque Bohemise. Inaug. Diss. 4to. Frankfurt a. d. Oder, 1760. 

Gronovii, (L. T.,} Bibliotheca Regni Animalis et Lapidei. 4to. Luyd. 

Bat. 1760.

APPENDIX. 473 

Natter, (Lgurentius,) Catalogue des Pierres gravies de Mylord Comte 

de Besborougli. 4to. London, 1761. 

Pouget, (N.,) Traite des Pierres precieuses, et de la maniere de les 

employer en parure. 4to. Paris, 1762. 

Vogel, (R. A. Praes.,) Terrarum atque lapidum partitio, resp. A. Fr. 

Hempel. 4to. Gdttingen, 1762. 

Walch, (J. E. J.,) Das Steinreich systematischentworfen. 2 vols. 

8vo. 24 plates. Halle, 1762. 

Bertrand, (E.,) Dictionnaire universel des fossiles propres 

et des 

fossiles accidentels, contenant une description des Terres Sables, 

&c. 8vo. 2 vols. in 1. La Haye, 1763. 

'Pheopliylacti Opera, a J. F. Bern, de Rubeis et Borif. Finettio, 

Greec. et Lat. 4 vols. Fol. Venet. 1754 and 1763. 

Justi, (J. H. G.,) Grundriss des gesammten Mineralreiclis. 

also in 1765. 

8vb. 

Gdttingen, 1757 ; 

Linnaeus, (C.,) Systema Naturae sive tria regna. Ed. I. Fol. Lugd.. 

Bat. 1735. Ed. XII., Holmice, 1766. 

Bertrand, (E.,) Recueil de divers TraiteV sur 1'Histoire Naturelle de 

la Terre et des Fossiles. 4to. Avignon, 1766. 

Bock, (Fr. S.,) Vesucb einer kurzen Naturgeschicbte des Preussischen 

Bernsteins, und einer neuen warscbeinlichen Erklarung seines 

1767. ' 

Ursprunges. 8vo. Kdnigsberg, 

Wallerius, (J. G.,) Lucrubrationum arademicarum specimen primum 

de systematibus mineralogicis et systemate mineralogico rite 

condendo. 8vo. Holmice, 1768. * 

Scopoli, (J. -A.,) Einleitung zur Kenntniss und Gebrauch der Fossilien. 

8vo. Riga und Milan, 1769. 

Baumer, (John Willi^ Historia Naturalis Lapidum preciosorum 

omnium, etc. 8vo. Franc. 1771. 

Bourguet, Du Regne Minerale. 4 vols. 12mo. Paris, 1771. 

Forster, (J. R.,) ClassiJBcation of Fossils and Minerals. London, 

1768 ; also in 1772. 

Scopoli, (J. A.,) Principia Mineralogiaa systematic^ et practical. 

Pragcs, 1772. 

Juwelier, Der Aufrichtige, oder Anweisung aller Arten Edelsteine, 

Diamanten, und Perlen zu erkennen, nebst einer aus dem 

Engliscben iibersetzten AbbandJung von den Diamenten und 

Perlen. 8vo. Frankfurt, 1772. 

Hodgson, (Rev. Jobn,) Dissertation on an Ancient Cornelian. ArcJwol. 

ii. 42. 1773.

474 APPENDIX. 

Bruckmann, (U. F. B.,) Abhandlung von Edelsteinen. Braunschweig, 

1757-73. 

Baiimer, (J. W.,) Naturgeschichte aller Edelsteine, wie auch der 

Erde und Steine, so bisher z'ur Artznei sind gebraucht worden. 

Aus dem Latein. von Karl, Freih. von Meidinger. 8vo. Wien, 

1774. 

Schroter, (J. S.,) Journal fiir die Liebhaber des Steinreichs. Weimar, 

1774. 

Werner, (Abr. G.,) Vender ausserlichen Kennzeichen der Fossilien. 

8vo. Leip. 1774. 

Bruckmann, (Fr. Hier.,) A Treatise on Precious Stones. 8vo. 1775. 

Born, (Baron Inigo,) Schneckensteine, oder die Sachsischen Topas- 

felsen. 4to. Prag. 1776. 

Collini, (Cosmus,) Journal d'un Voyage, qui contient differentes 

observations rnineralogiques, particulierement sur les agates, avec 

. un detail sur la maniere de travailler les agates. 8vo. Manrilieim, 

1776. 

Dutens, (Lewis,) Des Pierres precieuses et des Pierres fines, avec les 

moyens de les connoitre et de les valuer. Londres, 1776. 

Scopoli, (Jo.,) Ant. Crystallographia Hungarica. 4to. Prague, 1776. 

Vogel, (R. A.,) Practisches Mineralsystem. 2d ed. 8vo. Leip. 1776. 

Sage, Mineralogie docim'astique, with plates. 8vo. Paris, 1772 ; 

also in 2 vols. in 1777. 

Wallerius, (J. G.,) Systema Mineralogicum, quo Corpora Mineralia 

in classes, ordines, genera et species, suis cum va'r. divisa descri- 

buntur atque observationibus, experimentis et figuris illustrantur. 

2 vols. 8vo. Vindob.l. 

Bruckmann, (U. F. B.,) Gesammelte und eigane Beitrage zu seiner 

Abhandlung von Edelsteinen. Braunschweig, 1778. 

Bomare, (Valmont de,) Mineralogie, ou nouvelle exposition de Regne 

Minerale. 8vo. Pa/ris, 1769 ; also in 1774, 1780. 

Fichtel, (J. C. Von,) Mineralgeschichte. 4to., with plates. Ham- 

burgh, 1780. 

Haiiy, (Abbe de,) Traite de la Mineralogie. Paris, 1780. 

Regenbogen-Achat, Vom. 4to. Hamburgh, 1780. 

Gerhard, (C. A.,) Beitrage zur Chemie und Geschichte des Mmeral- 

reichs. 2 vols. 8vo. Berlin, 1773-1776 ', also in 1781. 

Lenz, (J. G.,) Tabellen iiber das gesammte Steinreich. 4to. Jena, 

1781. 

Bergmann, (T.,) Sciagraphia regni mineralis secundum principia 

proxuna digesti. 8vo. Lipsice, 1782.

APPENDIX. 475 

jjj 

Buchoz, Lee Dons merveilleux et diversement colories de la Nature 

dans le Regne Mineral. Fol. Para,. 1783. 

(^.rosi, (Johann,) Sur la Generation du Silex du Quarz. 8vo. 

Oracm. 1783. 

Rome de L'Isle, Essai de Cristallographie. 8vo. Paris, 1772. 2d 

ed. in 4 vols. 8vo. 1783. 

M. Buffon, (Le Comte de,) Histoire Naturelle des Mineraux. 4to. 

Paris, 1783. 

Faujas de Saint Fond, (B.,) Mineralogie des Volcans ou Description 

de toutes les substances produits ou rejetees par les feux souter- 

rains. Royal 8vo. Paris, 1784. 

Daubenton, Tableaux methodiqtie des Mine'raux suivant leurs differentes 

natures. 4to. Paris, 1784. 

Ravius, (S. F.,) Specimen Arabicum, continens descriptionem et ex- 

cerpta libri Achmedis Teifascbii ' De Gemmis et Lapidibus Pre- 

tiosis/ Arabic. Trapetum ad Rhenum, 1784. 

Haiiy, (Rene Just.,) Essay d'une Theorie BUT la structure des Cristaux. 

8vo. Paris, 1784. 

: 

- 

Cadet, (Le Jeune,) Memoire sur les Jaspes et autres Pierres precieuses 

de 1'ile de Corse, etc. 8vo. Bastia, 1785. 

Genuine Account of the present state of the Diamond Trade in the 

Dominions of Portugal, with some authentic pieces, in a letter 

from a merchant in Lisbon to his Correspondent in London. 4to. 

L

476 APPENDIX. 

De Born, Catalogue de la collection des Fossiles de Eleonore de 

Raab. 2 vols. 8vo. Vienna, 1790. 

Lenz, (J. G.,) Mineralogisclies Handbucli durch weitere Ausfuhrui% 

des Wernerschen Systems. 8vo. Hildburghausen, 1791. 

Catalogue des Bijoux nationaux. Paris, 1791. 

Lehman, (J. A.,) Entwurf, einer Mineralogie. 

1857 also in 1769 and 1791. 

; 

8vo. Frank/, et Leip. 

Gallitzin, (Le Prince Dimitri de,) Traite ou Description abregee 

methodiques' des Mineraux. 4to. Maastricht, 1792. 

Emmerling, (L. A.,) Lehrbuch der Mineralogie. 8vo. Giezen, 1793. 

Veltheim, (A. V. von,) Reformen in der Mineralogie. 8vo. Helm. 

1793. 

Bekkerheim, (Karl,) Krystallographie des Mineralreichs. 8vo. Wien, 

1793. 

Veltheim, (A. F. von,) Etwas iiber Memnons Bildsaule, Nero's 

Smaragd, Toreutik, und die Kunst der Alten in Stein und Glas 

zu sclmeiden. 8vo. Helmstadt, 1793. 

Wulfinii Descriptlo Helmintholiti pulcherrimi versicoloris in marmore 

Corinthiaco. 4to. Erlangce, 1794. 

Lenz, (J. G.,) Vollstandig Einleitung zur Kenntniss der Mineralien. 

2 vols. 8vo. Leipz. 1794. 

Kirwan, (R.,) Elements of Mineralogy. 8vo. London, -1784 ; 2d 

ed. 1794. 

Schmeisser, (J. G.,) System of Mineralogy. Vol. 1. 8vo. London, 

1794. 

Wiedenmann, Handbuch der Oryktognostichen Theils der Mineralo- 

1794. . 

gie. 2 vols. 8vo. Leipzig, 

Del Rio, (Don Andres Manuel,) Elementos de Oryktognosia 6 del 

conocimiento de los fossiles, dispuestos segun los principios de A. 

G. Werner. .4to. Mexico, 1795. 

Retzius, (A. J.,) Forsok til Mineral-Rikets Upstallning. 

1795. 

8vo. Lund. 

Forster, (J. R.,) Onomatologia nova systematis oryktognosise, voca- 

bulis latinis expressa. Fol. Halce, 1795. 

Psellus, )Michael Cohstantinus,) De Lapidum Virtutibus, Gra3ce ac 

Latine. 8vo. Lugduni Batavorum, 1795. 

âbington, (Charles,) A Systematic Arrangement of Minerals, their 

Chemical, Physical, and External Characters. 4to. London, 1795. 

Ekeberg, (Andrew Gustavus,) Dissertatio de Topazio. Ifpsal, 1796, 

Hasse, (J. H, F..) Der Aufgefundene Eridanus, oder neue Aufsch- 

lus,se iiber den Ursprung des Bernsteins. 8vo. Riga, 1796.

APPENDIX. 477 

Napione, Element! di Mineralogia. 8vo. Turin, 1796. 

Gerhard, (G. A.,) Grundriss des Mineralsystems. 8vo. Berlin, 

1786 and 1797. 

Andrada, (M. d',) An Account of the Diamonds of Brazil. Nich. 

Journ i. 24 1797. 

* 

Diamond, The, or the Pest of a Day. Fores. 4to. London, 1797. 

Tennant, (Smithson, Esq., F. R. S.,) On the Nature of the Diamond. 

Phil.Trans 1797, xviii 97, and Nich. Journ. i. 177. 1797. 

Veltheim, (A. F. von,) Etwas iiber das Onyx-Gebirge des Clesias 

1 797. 

und den Handel der Alten nach Ost-Indien. 8vo. Helrwtadt, 

Bouruon, (Count de,) An Analytical Description of the "Crystalline 

.Forms of Corundum from the East Indies and China. Phil. 

Trans. At>r. xviii 368. 1798. 

Struve, (H.,) Methode Analytique desFossiles, fondee surleurs Carac- 

teres Exterieurs. 8vo. Lausanne, 1797 ; 8vo. Paris, 1798. 

Townson, (R.,) Philosophy of Mineralogy. 8vo, Plates. London, 

1798. 

Reuss, (F. A.,) Lexicon Mineralogicum, sive Index Latino-Gallico- 

Suecico-Danico-Angnco-Russico-Hungarico-Germanicus Minerali- 

*mn. 8vo. Cura Regis. Leip. 1798. 

GreviUe, (Rt. Hon. Charles, F. R. S.,) On the Corundum Stone from 

Asia. Phil.- Tram. Abr. xviii. 356, 1798, and NicJi. Journ, ii, 477. 

1799. 

Guyton-Morveau, (B. L.,) Verbal Process of the conversion of Soft 

Iron into Cast Steel by means of the Diamond. Nich. Journ. iii. 

353. 1799. 

Klaproth, (Martin Henry,) Analysis of the Spinel. Nich. Journ, iii. 

549. 1799. 

Palm, (J. J.,) Dissertatio gradualis sistens observationes nonnullas 

de Lapide Obsidiano. 4to. Londoni Gothorum, 1799. 

Babington, A Systematic Arrangement of Minerals. 4to. London, 

1795 ; 1799. 

Batsch, (A. J. G. K.,) Versuch einer Anleitung zur Kenntniss und 

Geschiehte der Thiere und Mineralien. 2 Bde. 8vo. Jena, 1788, 

1789 ; 

also 1796-1800. 

Jameson, (Robert,) Mineralogy of the Scottish Isles. Maps and 

Plates. 2 vols. 4to. Edinburgh, 1800. 

Brunner, (J.,) Versuch einer neuen Systems der Mineralogie. 8v r o. 

Leipzig, 1800. 

Blindheim, (J. J.,) Ueber den Sibirischen und Taurischen Kalzedon. 

Neue Schrift. der GeseUsch. naturf. Freunde. 4to. Berlin, 18CO.

478 APPENDIX. 

Mackenzie, (Sir Geo. Stewart, Bart., F. R. S. L. & E.,) Experiments 

on the Combustion of the Diamond, the Formation of Steel by its 

Combination with Iron, etc. Nich. Journ. iv. 103. 1800. 

BournoH, (Count de,) Description of the Corundum Stone, and its 

Varieties commonly known as Oriental Ruby, Sapphire/ e.tc. Phil. 

Trans, p. 223. 1801. 

Kohler, (H. K. A. von,) Untersuchung iiber den Sard, Onyx, und 

Sardonix. 8vo. Braunschweig, 1801. ' 

,-V 

Ur, (Fr. Ben.,) Ueber den Sarder Onyx und Sardonyx ; also, Nach- 

trag iiber, etc., 1804. Braunschiceig, 1801. 

Hoff, (A. von,) Magazin fur die gesammte Mineralogie, &c., pi. 

Leipz. 1801. 

8vo. 

Haiiy, (L'Abbe,) Traite de Mineralogie. 8 vols. 8vo. Paris, 1801-2. 

Mawe, Mineralogy of Derbyshire. 8vo. Plates. London,. 1802. 

Dolomieu, (D. de,) Sur la Philosophic Mineralogique et sur Fespece 

Mineralogique. 8vo. Paris, 1802. 

Klaproth, (Martin Heinrich,) Beytrage zur Chemischen Kenntniss 

der Mineralkorper. 3 B. 8vo. Berlin, 1795-1802. 

Biehle, (Von,) Ueber die Bernstein-Grabereien in Hinter-Pommeru. 

8vo. Berlin, 1802. 

Chenevix, (Richard, Esq., F. R. S.,) Analysis of Corundum and some 

Substances that accompany it. Phil. Trans, p. 327. 1802. 

Haiiy, Memoire sur les Topazes du Bresil. Ann. du Mus. Paris, 

1802. 

Schwarze, (Christ. Aug.,) De Smaragdo Veterum. 4to. Gorlicii, 1802. 

Lenk, (J.,) Neue Entdeckung eines Steines Serpentin-Agat. Wie?i, 

1802. 

Gregor, (Rev. William, M. A.,) An Analysis of a variety of the Corundum. 

Nich. Journ. iv. 209. 1803. 

Schwarze, (Christ. Aug.,) De quodam Pseudo-Smaragdorum apud 

veteres genere. 4to. Gorlicii, 1803. 

Hausmann, (J. F. L.,) Krystallogische Beitrage. 4to. PL 1803. 

Ludwig, (C. F.,) Handbuch der Mineralogie nach A. G. Werner.- 

8vo. Leipzig, 1803. 

Lucas, (J. A. H.,) Tableau Methodique des especes minerales. 8vo. 

Paris and Strasb. 1803. 

Schwarz, (G. M.,) Handbok i Oryktognosien. 

Launnas, (L. de,) Mineralogie 

8vo. 1803. 

and Paris, 1803. 

des Anciens. 2 vols. 8vo. Bruxelles 

Rozin, Essai sur Fetude de la Mineralogie. 8vo. 368 pp. Bruxelles, 

1803.

APPENDIX. 479 

Mohs, (Priederich,) Handbuch der Oryktognosie. 3 vols. 8vo. Wien, 

1804 

Accmn, (F.,) Elements of Crystallography, after the manner of Haiiy. 

8vo. plates. London, 1804. 

Accum, (F.,) Analysis of Minerals. 12mo. London, 1804. 

Suckow, Anfangsgriinde der Mineralogie. 8vo. Leipzig, 1790 ; 2d 

ed. 2 vols. 8vo. 1803-4. 

Haberle, (C. C.,) Bêobachtungen 

iiber die Gestalt der Grand und 

Keimkrystalle des schorlartigen Berylls, nnd dessen iibrige. 

oryctognostiche und geognostische Verhaltnisse. Erfurt, 1804. 

Meineke, (J. L. G.,) Ueber den Chrysopras und die denselben begleitenden 

Fossilien in Schlesien. 4to. Erlangen, 1805. 

Jameson, (Robert,) A Treatise on the External Characters of Minerals. 

8vo. Edinburgh and London, 1804-1805. 

Haberle, (C. C.,) Beitrage zu einer allgemeinen Einleitung in das 

Studium der Mineralogie. 8vo. Weimar, 1805. 

Haberle, (C. C.,) Characterisirende Darstellung der Mineralien mit 

Hinsicht auf Werner et Hauy's beobachtungen. 8vo. Weimar, 

1806. 

Reuss, (F. A.,) Lehrbuch der Mineralogie nach Karsten's Tabellen. 

8vo. Leipzig, 1801-1806. 

Flade, (C. G.,) De Re Metallica Midianitarum et Phoenicorum. 4to. 

Leipzig, 1806. 

Berzelius, (J. Jacob, M. D., F. S. A.,) On the Composition of the 

Topaz, etc, Nich. Journ. ix. 105. 1807. 

Brongniart, Traite de Mineralogie, avec application aux Arts. Paris, 

1807. 

Eckennan, (N.,) Electra, oder die Entstehung des Bernsteins. 4to. 

Halle, 1807. 

Pepys, (William Hasledine, Treasurer of the Geol. Soc.,) On the 

Quantity of Carbon in Carbonic Acid, and on the Nature of the 

Diamond. Phil. Trans, p. 267, and Nich. Journ. xix. 267. 1807. 

Brochant de Villiers, (A. J. M.,) Traite Elementaire de Mineraux 

suivant les principes de Werner. 2 vols. 8vo. Paris; also 1807. 

Leonhard, (C. C.,) Taschenbuch fur die gesammte Mineralogie mit 

Hinsicht auf die neueste Entdeckungen. 8vo. 1807. 

Accum, (F.,) Manual of Analytical Mineralogy. 2 vols. PI. London, 

1808.- ^ 

Karsten, (D. L. G.,) Tabellarische Uebersicht der mineralogischen 

einfach.en Fossilien. 8vo. 2te. Aufg. Berlin, 1792 ; also 1800, 

1808. 

'

480 APPENDIX. 

Bournon, (Le Comte de,) Trait e de la Chaux Carbonate et do 

1'Arragonite, auquel on a joint une introduction a la Mineralogie 

en general, une Theorie de la Crystallisation et son Application. 

4to. Londres, 1808. 

Brard, (C. P.,) Traite des Pierres precieuses. Paris, 1808. 

Haiiy, Sur la Reunion de la Pycnite avec le 1808. 

Topaze. 4to. Pans, 

Gautier, (J.,) Untersuchung fiber die Entstehung^, Bildung und den 

Bau des Cbalcedons, etc. Jena, 1809. 

Hausmann, (J. F. L.,) Entwurf eines Systems der unorganisirten 

Naturkorper. 8vo. Cassel, 1809. . 

Weiss, De indagando formarum crystallinarum cliaractere geometrico 

principal!. Lipsice, 1809. 

Lenz, (J. G.,) System der Mineralkorper. 8vo. also in 1809. 

Bamberg 

1800 ; 

und Wurzb. 

Petzl, (J.,) Ueber den glatten'Beryll von Rabenstein im Bayrischeri 

Walde. Abb. der Kon. Akad. 4to. Munchen, 1809-1810. 

Guyton-Morveau, (B. L.,) On the singular Crystallization of the 

Diamond. Nich. Journ. xxv. 67. 1810. 

G lithe, (J. M.,) Ueber den Asterios-Edelstein des Cajus Pliniiis 

Secundus ; eine antiquarisch-lithognostische Abhandlung. 4to. 

Munchen, 1810. 

Fischer, (G.,) Essai sur la Turquoise et sur la Calaite. Moscou, 

1810. 

Accum, (F.,) System of Mineralogy and Mineralogical Chemistry. 

4 vols. 8vo. London, 1810. 

Dree, (Marquis de,) Catalogue de Musee Mineralogique. 4to. Paris, 

1811. 

Maculloch, (John, M. D., F. 'L. S.,) Remarks on. Several Parts of 

Scotland which exhibit Quartz Rocks, and on the Nature and 

Connection of this Rock in general. Geol. Trans, i. 450. 1811. 

Chenevix, (R.,) On Mineralogical Systems. 8vo. London, 1811. 

Silliman, (B.,) Mineralogy and Geology of New-Haven, in a statistical 

account of the City of New-Haven, by Pres. Timothy Dwight, 

published by the Connecticut Academy of Arts and Sciences. 

New-Haven, 1811. 

8vo. 

Niizlein, (F. A., Versuch eine neuen Systems der mineralogischeinfachen 

Fossilien. Bamberg and Wurzburg, 1810, 1812. 

Lenz, (J. G.,) Erkenntnisslehre der Anorganischer Naturkorper. 

Giesen, 1813.

APPENDIX. 481 

Lucas, (J. A. H.,) Tableau Methodique des Especes Minerales. 8vo. 

Paris, 1806-1813. 

Bournon, (Comte de,) Catalogue de sa collection Mineralogique. 8vo. 

with 4to. plates. 1813. 

Mawe, (John,) A Treatise on Diamonds and Precious Stones, in- 

cluding their History, Natural and Commercial. To which is 

added some account of the best method of cutting and polishing 

them. 8vo. London, 1813. 

Brewster, (Sir David,) On the Optical Properties of Sulfuret of Car- 

bon, etc., with Inferences respecting the Structure of Doubly-refracting 

Crystals. Fol. Edinb. 1814. 

Davy, (Sir Humphry,) Prof, of Chem., etc., etc., Some Experiments 

on the Combustion of the Diamond and other Carbonaceous Sub- 

stances. Phil. Tram. p. 557. 1814. 

Aiken, (Arthur,) Manual of Mineralogy. 8vo. London, 1814. 

Allan, Mineralogical Nomenclature. 8vo. London, 1814. 

Gravenhorst,(J.L.C.,) Handbuchder Anorganognosie. 8vo. Leipzig, 

1815. 

Berzelius, (J. J.,) Versuch durch Anwendung der elektrisch chemischen 

Theorie und der chemischen Verhaltnisslehre, ein rein wiseenchaftliches 

System der Mineralogie zu begriinden. Aus dem 

Schwed von Dr. A. F. Gehlen. 8vo. Niirnberg, 1815. 

*Aikin, (A.,) Manual of Mineralogy. 12mo. Philadelphia, 1815. 

Bournon, (C. de,) A Descriptive Catalogue of Diamonds in the Cabinet 

of Sir Abraham Hume. 4to. London, 1815. 

Brewster, (Sir David,) On a New Optical and Mineralogical Property 

of Calcareous Spar. 4to. Edinb. 1815. 

Hauy, Observations sur les Tourmalines, particulierement sur celles 

qui se trouvent dans les Etats-TJnis. Mem. du Mus. Paris, 1815. 

John, (J. F.,) Naturgeschichte des Succins, oder des sogenannten 

Bernsteins. 8w>. Koln, 1816. 

Swedenstierna, (E. T.,) An Account of the Swedish Corundum, from 

Gellivara, in Lapland. Geol. Trans, iii. 415. 1816. 

Svedenstjerna, (E. Th.,) Ueber den Korund zu Gellivara in Lapland, 

ubersetzt von Dr. Hessel. Leonh. Taschenb. Frankfurt-a.-N. 1816. 

Berzelius, (J. J.,) Neues System der Mineralogie, aus dem Schwedischen 

von Dr. Gmelin und Pfaff. 8vo. Nurnberg, 1816. 

* Reprinted foreign works arc indicated by an asterisk.

482 APPENDIX. 

Tondi, Element! di Orittognosia. 2 vols. 8vo. Napoli, 1817. 

Haiiy, (L'Abbe,) Trait e des caracteres physique des pierres. 8vo. 

figs. Paris, 1817. 

Sowerby, Britisli Mineralogy. 8vo. London, 1802-1817. 

Leonhard, (C. C.,) R. F. Menz, und J. H. Kopp, Systematisch-Tabellarische 

Uebersiclit und Characteristik der Mineralkorper. 2 vols. 

Fol. Frankfort, 1806 ; 2d edit. 1817. 

*Phillips, (Wm.,) Outlines of Mineralogy and Geology. 12mo. New- 

York, 1817. 

Zappe, Mineralogische Abliandlungen. Wien, 1817. 

Haiiy, (Rene Just.,) Traite des Caracteres physiques des Pierres precieuses, 

pour servir a leur determination lorsqu'elles sont taillees. 

8vo. Paris, 1817. 

Brewster, (Sir David, LL. D.,F.R. S. L.etc,,) On the Optical Properties 

of Muriate of Soda, Fluate of Lime, and the Diamond, as ex- 

hibited in their action upon Polarized Light. Phil. Trans, viii. 

. 157. 1817. 

Brewster, (Sir David,) t)n the Effects of Compression and Dilatation 

altering the Polarizing Structure of Doubly-refracting Crystals. 

4to. Edirib. 1818. 

Carton, (J.,) Englischer Juwelier, Kenntniss, Werthund Preisschatzung 

aller Edelsteine, Perlen und Corallen, ins Deut. iibersetzt 

nach der 10 ed. 12mo. Ordtz, 1818. 

Fisher, (G. de Waldheim,) Essai sur la Pellegrina, ou la Perde Incomparable 

des freresZozima. Pamp. Hist. Nat. 8vo. Moscou, 

1818. 

Teifascite, (Ahmed,) Fior di Pensieri sulle Pietre Preziose, opera 

stampata nel suo originale Arabo di Ant. RainSri. 4to. Firenze, 

1818. 

Jameson, (Robert,) System of Mineralogy. 2 vols. pi. 8vo. Edin- 

&wr^,1804; 2ded. 1816; 3d ed. 1818. 

Hoffmann, (C. A. E.,) Handbuch der Mineralogie mit Fortsetzung von 

A. Breithaupt. 4 vols. Freylerg, 1811-1818. 

^Phillips, (Wm.,) Elementary Introduction to the Knowledge of 

Mineralogy, with notes and additions on American Articles, by 

Samuel L. Mitchijl. 12mo. New-York, 1818. 

Dana, (James Freeman,) Outlines of the Mineralogy and Geology of 

Boston and its environs. 8vo. Boston, 1818. 

*Thomson, (Thomas,) System of Chemistry, in 4 vols. Svo., the 3d 

containing a Treatise on Mineralogy. Edited by Thomas Cooper, 

from the 5th London edition. PMladelphia, 1818.

APPENDIX. 483 

Bakewell, (R.,) Introduction to Mineralogy. 8vo. London, 1819. 

Schoolcraft, (Henry R.,) A view of the Lead Mines of Missouri, 

including observations on the Mineralogy, Geology, Geography, 

&c., of Missouri and Arkansaw, and other portions of the Western 

Country. 2 plates, 300 pp. 8vo. New-York, 1819. 

Fladung, Versuch iiber die Kennzeichen der Edelsteine und deren 

vortheilhaftesten Sclinitt. Pesth, 1819. 

Brochant de Villiers, (A. J. M.,) Sur la cristallisation geometriquement 

et physiquement consideree. With numerous plates. 8vo. 

Strasburg, 1819. 

Frischholz, (J.,) Lehrbuch der Steinschneidekunst, fur Steinschneider, 

Graveurs, etc., und jedens welcher sich iiber die Veredlung der 

Steine zu unterrichten wiinscht. Mvnchen, 1820. 

Harris, (Thaddeus M.,) The Natural History -of the Bible, or a 

description of all the quadrupeds, birds, fishes, &c., precious stones, 

&c., mentioned in the Bible. 476 pp. 8vo. Boston, 1820. 

Hausmann, (J. F. L.,) Untersuchungen iiber die Formen der leblosen 

Natur Ir. Bd. 4to. mit vielen Kupfern. Gottingen, 1821. 

Mohs, (Friederich,) Die Charaktere der Classen, Ordnungen, Geschlechten 

und Arten, oder die Charakteristik der naturhistorischen 

Mineral-systems. 8vo. Dresden, 1821. 

Brard, (C. P.,) Mineralogie appliquee aux arts. 3 vols. 8vo. Paris, 1821. 

Berzelius, (J. J.,) Von der Anwendung des Lothrohrs in der Chemie 

und Mineralogie Aus der Handschrift ubersetzt von Heinr. Rose. 

; 

8vo. Number g, 1821. 

Berzelius, (J. J.,) The same, translated by J. G. Children. 8vo. 3 

pi. London, 1822. 

Kick, (Z.,) Tentamen JVIineralogicum, seu Mineralium nova distributio 

in classes, ordines, genera, &c. 8vo. BruxeUes, 1821. 

Koratz, (Michel,) Lexicon Mineralogicum enneaglottum. 8vo. Pest. 

. 

1821. 

Haiiy, (L'Abbe,) Traite de CrystaUographie. 2 vols. 8vo. Perns, 1822. 

Haiiy, (L'Abbe,) Traite de Mineralogie. 4 vols. 8vo. Paris, 1822. 

Cleaveland, (Parker,) Elementary Treatise on Mineralogy and Ge- 

ology. 670 pp. 8vo. Boston, 1816 ; 2d edit, in 2 vols. 8vo. Boston, 

1822. 

*Lowry, (Delvalle,) Conversations on Mineralogy and Geology. 

Philadelphia, 1822. 

Blumhof, (J. C.,) Lehrbuch der Lithurgik. Frankfurt, 1822. 

Cohen, (M.,) Beschreibendes Verzeichniss einer Sammlung von Diamanten. 

Wien, 1822.

484 APPENDIX. 

Mackenzie, (Sir G. S.,) On tlie Formation of Chalcedony. 4ta PMl. 

Trans. London, 1832. 

Partsch, (P.,) Besclireibendes Verzeichniss einer Sammlung von 

Diamenten und der zur Bearbeitung derselben nothwendigen Apparate, 

etc. Wien, 1822. 

Neumann, Beitrage zur Kristallonomie. 8vo. Berlin, 1823. 

Kosk, (M. F.,) Beitrage zur Kenntniss krys tallin Huttenproducte. 

8vo. Gdttingen, 1823. 

Breithaupt,*(A.,) Vollstandige Charakteristik des Mineral-systems. 

8vo. Dresden, 1823. 

Renier, (S. A.,) Element! di Mineralogia. 8vo. Padua, 1823. 

Phillips, (Wm.,) An elementary introduction to the knowledge of 

Mineralogy. 8vo. London, 1823. 

Bellerinan, (J. J.,) Die Urim und Thummin. Berlin, 1824. 

Glocker, (Ernst Friedrich,) De Gemmis Plinii, imprimis de Topazio. 

8vo. Vratislaviai (Breslau,) 1824. 

Brongniart, (Alex.,) Introduction a la Mineralogie. 8vo. Paris, 

1801 ; 2d edit, in 1824. 

Brard, (C. P.,) Manuel du Mineralogiste. 12mo. Paris, 1808 ; 3d 

edit. 1824. 

Steffens, Vollstandiges Handbuch der Oryktognosie. 4 vols. 8vo. 

Halle, 1811-1824. 

Stchegloff, (N.,) Mineralpguia po sistemie Gospodinda Haiiy. 2 

vols. 8vo. St. Petersburg, 1824. 

Webster, Catalogue of Minerals in .the State of New-York. 

Albany, 

12mo. 

1824. 

Hall, (Frederick,) Catalogue of Minerals found in the State of Vermont, 

and in the adjacent States. 44 pp. 8vo. Hartford, 1824. 

Robinson, (Samuel,) Catalogue of American Minerals, with their 

localities} arranged in the order of the States. 8vo. 316 pp. 

Boston, 1825. 

Haidinger, (Wm.,) Treatise on Mineralogy, or the Natural History 

of the Mineral Kingdom ; translated from the German of Mohs. 

3 vols. 8vo. Edinburgh, 1825. 

Monticelli and Covelli, Atlaute della Mineralogia Vesuviana. 

Napoli, 

19 pi. 

1825. 

Marx, (Dr. C. M.,) Geschichte der Krystallkunde. 

und Baden, 1825. 

8vo. Carlsrulie 

Ragoumovsky, (Greg. Comte de,) Distribution Technique des Pierres 

precieuses, avec leurs Caracteres distinctifs. 8vo. Vienne, 1825.

APPENDIX. 485 

Rose, (G.,) Ueber den Felspath, Labrador, etc., Gilbert, Ann. Leipzig, 

1826. 

Leonhard, (C. C.,) Handbnch der Oryctognosie. 8vo. Heidelberg, 

1821 ; 2d edit. 1826. 

Phillips, (Wm.,) Outlines of Mineralogy and Geology. 3d edit. 8vo. 

London, 1818 ; 4th edit. 1826. 

Naumann, (G. FT.,) Entwurf der Lithurgik oder okonomischen 

Mineralogie. 8vo. Leipzig, 1826. 

Rau, (Ambros,) Lehrbuch der Mineralogie. 8vo. Wurzberg, 1826. 

Girardin et Lecoq, Elemens de Mineralogie appliquee aux science 

chimique. 2vols. 8ro.pl. Paris, 1826. 

Drapiez, Mineralogie Usuelle, 504 pp. 12mo. Paris, 1826. 

Blum, (J. R.,) Verzeichniss der geschnittenen Steine indem Konigl. 

Museum zu Berlin. 8vo. Berlin, 1827. 

Del Rio, (Don Andres Manuel,) Nuevo sistema M nerale. Mexico, 

1827. -,> 

Bredsdorf, (J. H.,) De notione speciei in regno minerali. 104 pp. 

12mo. Copenhagen, 1827. 

Desnos,(J. O.,) Precis de Mineralogie Moderne. 2 vols. 32mo.pl. 

formant20 et 21 livr. de TEncyclopedique portative. Paris, 1827. 

Glocker, (Dr.,) Grundriss der Mineralogie. 8vo. Bredau, 1827. 

Bernhardi, Beitrage zur Kenntniss der Cristallformen. Erfurt 

1827. 

Comstock, (J. L.,) Elements of Mineralogy, adapted to the use of 

Seminaries and private students. Ixxvi. and 338 pp. 8vo. Bos- 

ton, 1827 ; 2d edit. 12mo. 

Beumenberger, (J. G.,) Der Volkommene Juwelier. Weimar, 1828. 

Corsi, (Faust,) Delle Piedre antiche libri quattro. Roma, 1828. 

Fladung, (J. A. F.,) Edelsteinkunde. Sm. 8vo. Wien, 1828. 

Hausmann, (J. F. L.,) Handbuch der Mineralogie. 3 vols. 8vo. 

Gottingen, 1813 ; 2d edit. 1828. 

Breithaupt, (A.,) Physiotegie der Unorganischen Natur. 8vo. pi. 

Dresden, 1828. 

Blondeau, Manuel do Mineralogie. 18mo. Paris, 1825 ; 2d edit. 

1828. 

Naumann, (C. Fr.,) Lehrbuch der Mineralogie. 8vo. Berlin, 1828. 

Freisleben, (J. Ch.,) Magazin fur die Orictographie von sachsen. 

8vo. Freib&rg, 1828. 

Ermann, Beitrage zur Monographie des Marekasit, Turmalin und 

Brasilianischen Topas. From the works of the Berliner Akad. 

4to. Berlin, 1829.

486 

APPENDIX. 

Breithaupt, (A.,) Das Gesclileclit der Rhomboedrischen Turrnaline. 

Schweizzers Jahrbmh fur Chym. und Phys. 8vo. 1829. 

Glocker, (Dr.,) Uebersiclit der Krystallisations-systeme, etc. 48 pp. 

4tb. Breslau, 1829. 

Glocker, (Dr.,) Handbuch der Mineralogie fiir Vorlesungen und zum 

Privategebrauch bestimmt. 1829. 

Grasman, (J. Gunter,) Zur physischen Krystallonomie, und geometrischen 

Combinationslehre. 8vo. 184 pp. 3 pi. Stettin, 1829. 

Frankenheim, (M. L.,) De Cristallorum cohaesipne. Breslau, 1829. 

Haidinger, (Wm.,) Anfangsgrunde der Mineralogie. 15 pi. Leipzig, 

1829. 

Finder, De Adamante Commentatio Antiquaria. Berlin, 1829. 

Macauley, (James,) A sketch of the Geology and Mineralogy of the 

State of New-York, pp. 281-362, in a work entitled, " The Na- 

tural, Statistical and Civil History of the State of New-York, by 

James Macauley." 3 vols. 8vo. New- York, 1829. 

Engelhardt, (Ab. von,) Die Lagerstatte der Diamanten im Ural- 

Gebirge. 4to. Riga, 1830. 

Lancon, (H.,) L'Art du Lapidaire. Paris, 1830. 

Schulze, (H.,) Practisches Handbuch der Juwelierkunst und Edelsteinkunde. 

Quedlinburg und Leipzig, 1830. 

Vettermann, (A.,) Kurze Abhandlung iiber einige der vorziiglichsten 

. Classen der Buntsn oder Gefarbten Edelsteine. 8vo. Dresden, 

1830. 

Beudant, (F. S.,) Trait6 elementaire de Mineralogie. 

2d edit, in 2 vols. 8vo. 1830. 

8vo. Plates. 

Paris, 1834 ; 

Naumann, (C. Fr.,) Grundriss der Kystallographie. 8vo. Leipzig, 

1826 ; 2d edit. 2 vols. 1830. 

Glocker, (Dr.,) Handbuch der Mineralogie. 2 vols. 8vo. pi. Nurn- 

berg, 1831. 

Kobell, (Frantz von,) Charakteristik der Mineralien. Nurriberg,. 

1831. 

Heseell, Crystallometrie. Leipzig, 1831. 

Kupffer, Handbuch der rechnenden Kristallonomie. 4to. pi. St. 

Petersburg, 1831. 

Karsten, (Dr. C. J. B.,) System der Mineralogie geschichtlich statis- 

tisch, theoretisch und technisch. 5 vols. 8vo. and royal folio atlas, 

containing 51 plates. Berlin, 1831. 

Baldwin, (Ebenezer,) Annals of Yale College, in New-Haven, Con- 

necticut. 8vo. New-Haven, 1831. Contains a sketch of the Ge- 

ology and Mineralogy of the vicinity of Yale College.

APPENDIX. 487 

Proposals of the Phenix Mining Company, with a statement of the 

History and Character of their Mines in Granby, Conn. 30 pp. 

8vo. New-York, 1831. 

Abich, (H.,) De Spinello, dissert, inaug. chem. 8vo. Berolini, 

1831. 

sur les Diamans de 1'Oural. 

Parrot^Notices 9 

4to. Mem. de I'Acad. 

Imp. St. Petersburg, 1832. 

Walchner, Handbuch der gesammte Mineralogie. 1104 pp. 8vo. 

Carlsruhe, 1832. 

Emmons, (Ebenezer,) Manual of Mineralogy and Geology. 230 pp. 

12mo. Albany, 1826 ; 2d edit. 299 pp. 12mo. Albany, 1832. 

Jackson, (C. T.,) and Francis Alger, Remarks on the Mineralogy of 

Nova Scotia. 1 pi. 115 pp. 8vo. Cambridge, Mass., 1832. 

Del Rio, (C. Andres,) Elementos de Oryctognosia. ' 

8vo. Philadel- 

phia, 1832. 

Mohs, (Friederich,) Der Naturgeschichte des Mineralreichs. Wien, 

1832. 

Brard, (C. P.,) .Description historique de sa collection de Mineralogie 

appliquee aux arts. 8vo. Paris, 1833. 

Kobell, (Frantz von,) Tafeln zur Bestimmung der Mineralien, etc. 

4to. Munich, 1833. 

Presl, (M. K. B.,) Anleitung zum Selbststudium der Oryctognosie. 

8vo. Prague, 1833. 

Catullo, Element! de Mineralogia applicata alia medicina e alia farmacia. 

2 vols. 8vo. Padua, 1833. 

Rose, (M. Gustav,) Elemente der Krystallographie. 8vo. 10 pi. 

Berlin, 1833. 

Uhde, Versuch einer genetischen Entwickelung, &c. A Philoso- 

phical Essay on the Mechanical Laws of Crystallization. 

Breme, 1833. 

8vo. 4 pi. 

Prestel, (A. E.,) Anleitung zur perspective Entwerfung, &c. On the 

Perspective projection of Crystalline forms. 8vo. pi. Gottingen, 

1833. 

Welsh, (Jane Kilby,) Familiar Lessons in Mineralogy and Geology, 

designed for the use of young persons and Lyceums. 2 vols. 

12mo. Boston, 1833. 

Hitchcock, (Edward,) Report on the Geology, Mineralogy, Botany 

and Zoology of Massachusetts, made and published by order of 

that State. 700 pp. 8vo. Amherst, 1833. 

Cairne, (A.,) La Science des Pierres precieuses appliquee aux arts. 

Paris, 1833.

488 APPENDIX. 

Blum, (Dr. Reinliart,) Die Schmuckstejne. Heidelberg, 1828, und 

Taschenbuch der Edelsteinkunde. 12mo. Stutgart, 1834. 

Burch, (A.,) Handbuch fiir Juweliere. Weimar, 1834. 

Ilartmann, (C. F. A.,) Mineralogie. 8vo. pi. llmenau, 1828 ; also 

in 1834. 9 

Hartmann, (C. F. A.,) Repertorium der Mineralogie. 8vo. pi, Leipzig, 

1834. 

Allan, (Robert,) A Manual of Mineralogy. 350 pp. 8vo. Edinburgh, 

1834. 

Suckow, (M. G.,) Grundriss der Mineralogie. 8vo. Darmstadt, 1834. 

Mather, (William W.,) Sketch of the Geology and Mineralogy of 

New-London and Windham Counties, in Connecticut. 36 pp % 8vo. 

with a map. Norwich, 1834. 

Moore, (N. F.,) Ancient Mineralogy, or an Inquiry respecting Mineral 

Substances mentioned by the Ancients. 192 pp. 12mo. New- 

York, 1834. 

Porter, (Jacob,) Topographical Description and Historical Sketch of 

Plainfield, in Massachusetts. 44 pp. 8vo. Greenfield, 1834. 

Hartmann, (C. F. A.,) Grundziige der Mineralogie und Geologic. 

8vo. Nwrnberg, 1835. 

Richard, (A.,) Precis elementaire de Mineralogie. 8vo. pi. Paris, 

1835. 

Frankenheim, (M. .L.,) Die Lehre von der Cohasion, umfassend die 

Elasticitat der Gase, die Elasticitat und Coharenz der flussigeii 

und sesten Korper und die Krystallkunde. 502 pp. 8vo. Breslau, 

1835. 

Necker, Le regne mineral ramene aux methodes de 1'histoire 

naturelle. 2 vols. in 8vo. of above 400 pages each. Paris, 1835. 

Thomson, (Thomas,) Geology and Mineralogy, forming the third 

portion, or the fourth and fifth volumes of his System of Chemistry. 

2 vols. 8vo. London, 1835. 

Shepard, (Charles Upham,) Treatise on Mineralogy, 1st part one vol. 

12mo. New-Haven, 1832. 2d part consisting of descriptions of the 

species, and tables illustrative of their Natural and Chemical 

affinities. 2 vols. 12mo. with^SOO wood cuts. New-Haven, 1835. 

Kurr, Grundziige der okonom-techischen Mineralogie. 8vo. 1836. 

Hochsteller, Populare Mineralogie. 12 pi. 8vo. 1836. 

*Moffatt, (J. M.,) Mineralogy and Crystallography ; pp. 236-298 of 

the Scientific Class Book. Reprinted with additions from, the 

London edition, by Walter R. Johnson. 12mo. Phttadel/phia, 

1836.

APPENDIX. 489 

Gesner, (Abraham,) Remarks on the Geology and Mineralogy of 

Nova Scotia. 8vo. 272 pp. Halifax, 1837. 

Dowd, (J. A.,) System of Mineralogy. New-Haven, 1837. 

Feuchtwanger, (Lewis,) Treatise on Gems. New-York, 1838. 

Hertz, (B.,) Catalogue of Mr. Hope's Collection of Pearls and Precious 

Stones, systematically" arranged and described. 4to. London, 

1839. 

Rose, (G.,) De Novis quibusdam Fossilibus quae in montibus Uraliis 

inveniuntur, Chrysoberillum, Uralium, etc. 8vo. Berobini, 1839. 

Blum, (J. R.,) Lithurgik, oder Mineralien und Felsarten, nach ihrer 

Anwendung in Oekon., Artist, und Technischer Hinsicht systematisch 

abgehandelt. Stutgart, 1840. 

Roy, (C. W. van,) Ansichten iiber Entstehung und Vorkommen des 

Bernsteins, so wie praktische Mittheilungen iiber den Werth und 

die Behandlung desselben als Handelsware. 8vo. Dantzig, 1840. 

Konneritz, (L. von,) Mittheilung mannichfaltiger Versuche Edel- 

steine kunstgemass zu schleifen. Weimar, 1841. 

Steinbeck, Ueber die Bernstein-Gewinnung. 8vo. Brandenburg, 

1841. 

Petzholdt, (M.,) Beitrage zur Naturgeschichte des Diamantes. 8vo. 

- 

Dresden und Leipzig, 1843. 

Transactions of the Imperial Russian Mineralogical Society at St. 

Petersburg, 1842. 

Ramdedsberg, (C. F.,) Chemical Mineralogy. Berlin, 1843. 

Alger, (Francis,) Elementary Treatise on Mineralogy, by William 

Phillips. Boston, 1844. 

Bielhe, (Von,) Bernstein, ein gewichtiges Naturproduct des Konigreichs 

Danemark. 8vo. Hamburg, 1845. 

Haidinger, (W.,) Ueber den Pleochroismus dee Amethysts. Natur- 

mssenschaftliche Abhandlungen. Wien, 1846. 

Priifer, (V.,) Ueber die Krytalfonn der Lazulith. 4to. Naturwissensch. 

Abhand. Wien, 1847. 

Goepert, (H. R.,) Ueber Pflanzenahnliche Einschlusse in den Chalcedonen. 

8vo. 1848. 

Haidinger, (W.,) Ueber den Pleochroismus des Chrysoberylls. 

Berichte iiber Mittheilungen von Freunden der Naturwissenschaf- 

ten. 8vo. Wien, 1848. 

Haidinger, (W.,) Ueber eine neue Varietat von Amethyst. Derik- 

8chHfLd.Kais.Akad. 4tov Wien, 1849.

490 APPENDIX. 

* 

Harting, (P.,) Description d'un Diamant remarquable, contenant'des 

crystaux. Acad. roy. des Sciences. 4to. Amsterdam, 1850. 

Loew, Ueber den Bernstein und die Bernstein-Fauna. Berlin, 

1850. 

Zerrenner, (Dr. Carl,) De Adamanti Dissertatio. Lipsice, 1850. 

Zerrenner, (C.,) Anleitung zum Diamanten. Wasclien aus Seifenge- 

birge, Ufer-und Flusbett-Sand. 8vo. Leipzig, 1851. 

Hindmarsli, (R.,) Precious Stones, being an account of the Stones 

mentioned in the Sacred Scriptures. 8vo. London, 1851. 

Booth, Encyclopedia. Philadelphia, 1852. 

Rose, (G.,) Das Krystallo-Chemische Mineral-system. 8vo. Leipzig, 

1852. 

Haidinger, (W.,) Pleochroismus und Krystallstructur des Amethystes. 

Sitzungsber. der Kais. Akad. 8vo. Wien, 1854. 

Fontenelle, Nouveau Manuel Complet du Bijoutier. 8vo. Paris, 

1855. 

Labarte, (M. Jules,) Handbook of the Arts of the Middle Ages and 

Renaissance as applied to the Decoration of Jewels, Arms, etc. 

8vo. London, 1855. 

Schmidt, (C. J.,) Das Wichtigste iiber den Opal in Allgemeinen und 

iiber sein Vorkommen in Mahftsn im Besonderen. Mittheil. d. k. 

k. mdhr. scJiles. Gesellsch. Brunn, 1855. 

Volger, (G. H. O.,) Versuch einer Monographic des Borazites. 

ver, 1855. 

Hano- 

Volger, (G. H. 0.,) Epidot und Granat, Beobachtungen iiber das 

gegenseitige Verhiiltniss dieser Krystalle. 4to. Zurich, 1855. 

Kokscharow, (Nic. von,) Ueber die russischen Topase. 4to. Mem. 

de I'Acad. Imp. Petersbourg, 1856. 

Krause, (T. H.,) Pyrgoteles, oder die edeln Steine der Alten in 

Bereiche der Natur, etc. Halle, 1856. 

Loninser, (Gust.,) Die Marmaroscher Diamanten. 4to. Presburg, 

1856. 

Ritter, (C.,) Der Tu-(Yu-)stein, d. i. der Tu-chi der Chinesen, Kasch 

der Tiirken, Yeschet der Perser, oder Jaspis der Alten, sein Fun- 

dort in Khotan, sein Verbrauch und Handel. 8vo. Berlin, 1856. 

Ginanni, (Fantuzzi M.,) Osservazioni geognostiche sul Coloramento 

di alcune Pietre e sulla formazione di un Agata nel Museo Ginanni 

di Ravenna. 8vo. 1857. 

Mobius, (K.,) Die echten Perlen. 4to. Hamburg, 1857. 

Barbot, (Ch.,) Traite complet des Pierres precieuses. 8vo. Paris, 

1858.

APPENDED 

491 

V 

Haidinger, (W.,) Der fiir Diamant oder noch Werthvolleree aus- 

gegebene Topas des Herrn Dupoisat. Sitzungsber. der Kais. Akad. 

4to. Wien, 1858. 

Rudolph, (A.,) Die edeln Metalle und Schmucksteine, mit 37 TabeUen. 

Breslau, 1858. " 

Scheerer, (Th.,) Ueber den Traversellit und seine Begleiter Pyrgom, 

Epidot, Granat. Ein neuer Beitrag zur Beantwortung der Plutonischen 

Frage. Bericht. der Kngl. sdcJis. GeseUsch. 8vo. Leipzig, 

1858. 

Feuchtwanger, (Dr. L.,) A Popular Treatise on Gems, in reference 

to their scientific value, etc. 8vo. New-York, 1859. 

Hessh'ug, (Th. von,) Die Perlmuschel und ihre Perlen. 8vo. Leipzig, 

1859. 

Kluge, Edelsteinkunde. Leipzig, 1860. 

Pole, (W.,) Diamonds. 8vo. Land. Archaol. Trans. London, 1861. 

Pisani, (J.,) Sur le Grenat octoedrique de 1'Ile d'Elbe. 4to. Comptes 

rend, de VAcad. des Sciences. Paris, 1862. 

Sotto, (Js.,) Le Lapidaire du quatorzieme Siecle. 8vo. Wien, 1862. 

Zepharovitch, (V. v.,) Der Diamant, ein Popularer Vortrag. 8vo. 

Gratz, 1862. 

Lacaze, (Duthiers H.,) Histoire Naturelle du Corail, Organisation, 

Reproduction, Peche en Algerie, Industrie, etc. 8vo. Paris, 1864. 

Von Kobell, (Franz,) Die Mineralogie. Leipzig, 1864. 

Madelung, (A.,) Die Metamorphosen von Basalt und Chrysolith von 

Hotzendorf in Mahren. 4to. * Jahrb. d. Geol. Reichsanst. Wien, 

1864. 

Partsch, (P.,) Catalogue of the Geological Cabinet at Vienna, with 

a Biographical List of the Works treating on the subjects of Ge- 

ology, Oryctology, and Palaeontology. 8vo. Vienna, 1864. 

Emanuel, (H.,) Diamonds and Precious Stones. London, 1865. 

Annales des Mines. Paris. 

Boetius, (Anselmus,) Tractatus de Lapidibus et Gemmis. Var. ed. 

Bondary, (Jean de la Taille de,) Blason des Pierres precieuses. 

Bouillon, (De la Grange,) Analysis of the Substance known by the 

name of Turquoise. Nick. Journ. xxi. 182. 

Cardanus, (Hieronymus,) De Lapidibus preciosis ; also de Subtilitate. 

Var. ed. 

Guyton-Morveau, (B. L.,) Account of certain Experiments and Inferences 

respecting the combustion of the Diamond and the Nature 

of its composition. Nich. Journ. iii. 298. 

Kohler, (H. K. A. von,) Kleine Abhandlungen zur Gemmenkunde.

. 

492 .APPENDIX. 

Lucretius, De Rerum Natura. Var. ed. 

Mortimer, (Cromwell, M. D.,) Remarks on the Precious Stone called 

Turquois. Phil. Trans. Abr. viii. 324. London. 

Phillips, Mineralogy. Var. ed. 

Philostratus, De Vita Apollonii. Var. ed. 

Vauquelin, (Citizen,) Information respecting the earth of the Beryl. 

Mch.Journ.u. 393. 

Vauquelin, (Citizen,) Analysis of the Chrysolite of the Jewellers, 

proving it to be Phosphate of Lime. Nich. Journ. ii. 414. 

Vauquelin, (Citizen,) Analysis of the Aqua Marine or Beryl, etc. 

Nidi. Journ. ii. 358. 

Vega, (Garcilaso de la,) History of the Incas. Var. ed. 

Wecker, or Weckerus, Antidotae speciales de Lapidibus minus pretiosis 

alterantibus. 

Poggendorff's Annalen der Physik und Chemie. 

Brooks in the Encyclopedia Metropolitain. 

Berzelius' Annual Reports. 

London, Edinburgh and Dublin Philosophical Magazine. 

Jamieson's New Edinburgh Journal of Science. 

Brewster's Edinburgh Journal of Science. 

Thomson's Records of General Science. 

Reports of the British Association. 

De Ik Beche's Report. 

Silliman's American Journal of Science. 

Haiiy, (L. Abbe,) Tableau comparatif des resultas de la Crestallo- 

graphie et de 1'analyse chimique, relativement a la classification 

des mineraux. 8vo. Figs. Paris. 

Kidd, (J.,) Outlines of Minerology. 2 vols. 8vo. Oxford. 

Karsten's Archiv fur Mineralogie. 8vo. Berlin. 

Glocker, Mineralogischen Jahreshefte. 8vo. Breslau. 

Hartmann, Jahrbuch der Mineralogie, Geologie, &c. 8vo. 

Leonhard und Bronn, Neues Jahrbuch fur Mineralogie, Geographie, 

Geologie und Petrefaktenkunde. 8vo. 

The British Museum, containing some Ancient Manuscripts relating 

to the subject : 

Galamazar, Liber vertutibus Lapidum Pretiosorum quern scripsit 

Galamazar, Thesaurarius Regis Babylonie, ipso presenti et pre- 

cipiente. Harleian MSS. 8vo.

APPENDIX. 493 

De Lapidibus, Avibus et Arboribus Indiae, Arabiae et AMcae. Har- 

leian M88. 8vo. 

Lapidum Pretiosorum usus Magicus, sive de Sigillis. Harleian 

MS8. 8vo. 

Liber Hermetis tractans de 15 Stellis et de 15 Lapidibus et de 15 

Herbis et de 15 Figuris. Harleian MSS. 8vo.

494 

TABLE OF THE DISTINGUISHING

495 

CHARACTERISTICS OF GEMS.

496 


49' 

CHARACTERISTICS OF GEMS. ( Continued.)

498 


499 

CHARACTERISTICS OF GEMS. ( Continued.)

502 APPENDIX. 

The value of stones above five carats is not attempted to be given, 

as it is impossible to fix it with any accuracy. It depends entirely 

on the demand for any particular size and the supply in the market ; 

it remains a matter of negotiation between the buyer and seller. 

When a Diamond has a very decided color, such as blue, red, 

green, &c., it is called a fancy stone, and will bring a most exorbitant 

price. A stone of five grains, of a brilliant emerald-green color, for 

which, if white, not more than 28 stg. could be obtained, has been 

known to sell for 320 stg. The terms first water, second water, 

&c., mean only first and second quality. Diamonds, when perfect, 

should be clear as a drop of the purest water, and they are described 

as second or third water when more or less clear, until decidedly yellow 

or brown, when they are termed colored. The value of stones of 

the first quality of a less weight than two grains, (half a carat,) is, 

according to Mr. Emanuel, 10 stg. per carat ; the second quality, 

8 stg. ; the third, 7 stg. per carat. 

The plates representing the sizes of the Diamonds, given in this 

Treatise, are drawn from nature ; still it is quite difficult to get at 

the actual weight, for the Diamond cutters of the present day turn 

their attention more to the production of the greatest weight from 

a given quantity of rough Diamond, than to the production of perfectly 

proportioned stones, for which reason we often meet with 

stones weighing three carats, whose proper weight, if reasonably 

spread, should be two, which renders them less valuable and not 

nearly so brilliant as one of two carats properly cut ; any 

over or 

under weight only detracts from its beauty. A well proportioned 

spread Diamond finds more amateurs than a heavy one. At present 

the following prices may be quoted for Diamonds in gold currency, 

*2 grains, (half a carat,) from ......... $68 to $75, gold. 

* 4 grains are equal to 1 carat. 

151)6 carats 

" "1 ounce troy weight.

APPENDIX. 

503 

Mr. Emanuel's price list quotes for 1865, in pounds sterling and 

shillings : 

A Brilliant, weighing i of a carat, stg. 

" " " 

f 

" " 

" 

1 "...." 

5 10*. 5d. 

9 10 

18 

" " 

li 

" " " 

28 

ft 

-Jl 

(( ft 

gg 

**< 

' ~ \ 

" 

-'. 

If 

2 

" 

" 

" " 

" 

48 

65 

^-: w- 

*"'''-"' " 

2i 

2 

V-.--< ..,"/' 2f 

> 3 

3i 

3i 

3f 

'.'"*'. 4 "".;>; 

4J 

4i 

4| 

5 

: 

-* 

\- ".,':..;*;' 

" 

" 

" " 

"...." 

70 

88 

100 

" "...." 125 

" " 

.... 135 

" 

" 

" 

" 

...'. 

"...." 

* w 

150 

175 

220 

" " " 

230 

" 

" 

" " 

"...." 

250 

280 

" "...." 320 

The Rose Diamond, which is not much in use in Europe, but more 

in South America, has not a very fixed value. The small Rose Dia- 

monds, if under 40 to the carat, are worth about five shillings each ; 

above that size, and up to one carat, bring from 9 stg. to 11 stg. 

the carat. 

Ruby and Emerald. Both these gems, when really fine, free from 

any defect, in color or size, are worth as much as Diamonds of the 

same weight. ^ 

A fair Ruby is worth from $30 to $40 per carat. A fine and pure 

Ruby, well spread and proportioned, is worth, according to Mr. 

Emanuel 

Of 1 carat, stg. 14 to 20 

" " 

H 25 to 35 

2 

" " 

70 to 80 

" 

3 

" 

200 to 250 

4 

" " 

400to450 

And those below the weight of one carat range from 2 to 8 stg. 

while stones of greater weight than four carats are of 

per carat ;

504 APPENDIX. 

Bucli exceptional occurrence as to command fancy prices. Again, a 

Ruby of four carats, but of a pale color, may not be worth 12 stg. 

The Emerald is so rarely found perfect that the saying, "An 

Emerald without a flaw," has passed into a proverb. A good Em- 

erald is at the present day worth more than a Ruby, on account of 

the pleasing effect it has both by day and candle-light, and is a very 

favorite gem ; stands high in value ; but the Emeralds found lat- 

terly and brought into market are far inferior to those formerly 

found. A good Emerald is worth in this country $40 to $50 per 

carat. In England the price ranges from 5s. to 15 stg. per carat ; 

but one of deep, rich grass-green color, clear and free from flaws, 

may bring from 20 to 40 stg. per carat. 

Sapphire. A fine, perfect, evenly colored spread Sapphire, weighing 

one carat, of a deep rich blue color, by night as well as by day, 

is worth 20 stg. ; it does not, however, increase so much in isalue 

in proportion to its size. 

The Spinel or Balajs-Ruby, if of good quality, is sold from 10s. to 

8 stg. per carat. The value is extremely uncertain and variable ; 

it depends entirely on caprice and fashion. 

The Topaz. The commercial nature of the Topaz as a jewel is 

entirely fictitious. A very fine stone can now be bought for a few 

shillings sterling, whilq it would have brought a great deal more 

when in fashion. Pink Topaz brings from 2 stg. to 20 stg. per 

ounce, the price depending on the depth of the pink color. 

Beryl or Aquamarine. The commercial value of this stone is 

trifling, and is used mostly for imitation jewelry. Zircon, Hyacinth 

or Jacinth, are also called Jargoon. These stones, are identically the 

same, but differ in color ; the red varieties are sometimes sold for 

inferior Rubies. The Jargoon is frequently cut in the form of a Rose 

Diamond, which is flat at the bottom and pointed at the top. The 

price is purely%rbitrary. 

The Garnet, Essonite, Pyrope and Almandine. The color of the 

Syrian Garnet, being of deep crimson, is at present much in vogue, 

and commands a fair price, say from $1 to $2 per carat. 

The Bohemian Garnets are worth from $15 to $25 per ounce. 

Amethyst. A fine deep-colored stone, of the size of a twenty-five 

cent piece, is worth from $80 to $100 per ounce ; smaller sizes and 

inferior qualities are sold for 50 cents to $10 apiece. 

Peridote, Chrysolite. The value of both stones is but small ; fair 

specimens of good size may be bought at from 25c. to $5 per carat. 

Turquoise. The Persian is much used in jewelry ; small, clear

APPENDIX. 505 

stones bring from sixpence to 20*. stg. each, while a fine Ring 

stone will realize from 10 stg. to 40 stg. Large Turquoise, of 

good quality and fine color, are extremely rare, and realize extravagant 

prices. 

Opal. The value of the precious Opal depends entirely on the 

brilliancy and play of its colors ; large, fine gems, of extraordinary 

beauty, have brought fabulous prices. They are not sold by the 

carat, but by the piece. 

Coral. The red Coral, which formerly was the most valuable, is 

now worth far less than the color which was formerly worthless. 

The pale, delicate pink, similar to that of the inside of the pale rose 

leaf, is sought after, but very scarce ; a Coral of this tint is very 

valuable. 48 stg. per ounce has lately been paid in London. A 

large bead or drop will readily realize from 30 stg. to 40 stg. ; 

small pieces, however, may be had for $4 to $6 per ounce. 

Pearls. The value for perfectly pure round Pearls, of a smooth 

and lustrous skin, perfectly free from specks or discoloration of any 

sort, of small size, is from 4 grain Pearls, 

6 

" " 

$1 to 

2 to 

5 to 

$2 a grain. 

" 

3 

6 

10 

" " 

8 to 10 

The following is Mr. Emanuel's table of prices of Pearls, viz. : 

A Pearl of 1 grain is worth from 

" 

2 

" " " 

2*. to 

6s. Qd. to 

2*. Qd. 

7. Qd. 

3 

" " " 

12*. to 16*. 

4 

" " " 

22*. to 28*. 

5 

" " " 

35*. to 48*. 

6 

" " " 

55*. to 65*. 

8 

" " " 

90*. to 110*. 

" 

10 

12 

" 

" 

" 

" 

" 

" 

8 stg. to 

12 

9 stg. 

" 

to 15 " 

" 

14 

" " 

15 " 

to 18 " 

16 

" " " 

20 " 

to 30 " 

18 

" " " 

30 " 

to 40 " 

20 

" " " 

40 " 

to 50 " 

24 

" " 

60 " 

to 70 " 

30 

" " " 

80 " 

to 100 " 

Round Pearls above the latter weight are of such rare occurrence 

and command such exceptional prices, that it would be useless to 

attempt any scale of valuation.

14 DAY USE 

RETU RROWED 

RN TQJ)ESK ERO]VOWai] 

LOAN IDE.?!. 

This book is due on the last date stamped below, or 

on the date to which renewed. 

Renewed books are subject to immediate recall. 

LD 21-100m-6,'56 

(B9311slO)476 

University of California 

Berkeley

YB ,'5203

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