PRECIOUS STONES.*

IN this beautiful volume, got up as only his books ever seem to be got up, with a simple elegance in strict accord with his style, Mr. King endeavours to include all that is known upon the history and qualities of precioui stones. Long distinguished as an authority upon "gems" in the artistic sense of the word, he has in the course of his researches collected a vast quantity of information upon the materials employed for the designs he has studied so deeply, and this he has given to his readers in a series of papers • Precious Stones, Gems, and Precious Metals. By 0.W. Bing, M.A. London: Bell ad Daldr. each containing a complete account of some one stone, its nature and qualities, its uste in the- ancient world, its magic reputatiors in the Middle Ages, the modern estimate of its value, the best known plain examples, atvi if it has been used for engravings, the highest specimens of art o preserved which in the course of his researches have come before him. He adds chapters upon gold and silver, upon pastes and the various devices for swindling the collector, a translation of "Orpheus upon gems," the ancient song which professes to describe all the mystic qualities ascribed to stones in the ancient world, a chapter on prices, and another containing the chemical analysis of every stone. Of them all that on prices is

the only unsatisfactory one, the public really needing information such as only an experienced lapidary can give—a clue to compara- tive prices such as may enable them to check the trading jewellers,

whose profits, necessarily large, are unreasonably increased by- the ignorance of purchasers. Mr. King only informs us that

the ruby when exceeding a carat in weight costs more than the diamond, the price rising occasionally to 100/. a carat, that the average value of the diamond of the highest quality is 30/. a carat (?), that emeralds and sapphires are worth when fine about 3/. per carat, that a perfect turquois half an inch in diameter may be worth 10/., but the little turquoises like millet seed used to encrust jewels sell for sixpence a dozen, and

that Brazilian topazes in the rough are not worth more than 2L per pound. • None of these prices will in the least help the pur-

chaser, who will be told by the trade, which delights in fancy prices, that they are all absurd, and there are in practice, we fancy, only three rules worth much to the unskilled public when in search of really good stones. These are, first, never to buy of a jeweller, but always uns3t stones of a lapidary who deals in nothing else. He will give you an indefinitely larger choice at an

indefinitely lower price, and as you can really see an unset stone, you have at least the advantage of your eyes, which you have not when the stone is crusted up with what it pleases some jewellers. to call gold. Secondly, buy no stone of any value without a written statement of its weight, verified before the purchaser's eyes, and thirdly, recollect that all stones except the fines diamonds and rubies are cheaper than the popular impression

of their" price, and that the inferior stones—beryls, topazes, amethysts, turquoises, garnets, and onyxes, are comparatively very cheap indeed, being produced in quantities which ren- der enormous prices simply waste of money. The pink topaz, for example, often so highly valued by jewellers, is simply the yellow Brazilian topaz subjected to the action of fire, and.

the aqua marina, a stone sometimes almost as beautiful as the emerald, existing in such masses as to have lost almost entirely its. ancient value, the supply from Saxony, Siberia, and "America being

greatly in excess of the demand. "It possesses very great lustre, especially by lamp-light ; hence the lighter-coloured-varieties have long been used. in jewelry as fraudulent substitutes for the true diamond, a deception noted as early as the-end of the fifteenth century by Camillo Leonardo in treating of the tricks of the jewel-.

lers in his own times. At present it is similarly employed in Germany under the name of Diamond of the Rhine.' Hence it happens that people have often flattered themselves with being the owners of a diamond of enormous value, which, on examination by

a skilful lapidary, has turned out to be nothing more than a small, • worthless aquamarine. The stone has gone completely out of fashion in this country (though not in Italy), in consequence of the abundance in which it is now produced by the different regions above mentioned, and that too in masses often of enormous size,

their dimensions reminding us of the monstrous smaragdi spoken of by Apion and Theophrastus. Thus in the British Museum are

two beryls from Acworth, New Hampshire, one weighing 48 and the other 83 pounds." We have often wondered that the translu- cence of this stone, a quality in which it is unequalled by any other found in such quantities, has not tempted jewellers into wasting it a little by cutting it into imitative forms. A coronal of small vine-leaves cut in beryls would be far more beautiful than the tasteless crust of gems recently used for tiaras. The Oriental art of imitating flowers in gems alone, without the intervention of enamels, seems forgotten by our jewellers, and might be revived, to the immense improvement of the taste of the very rich. The amethyst also is a gem of very much lower value than the majority of people believe. The true "Oriental amethyst" is of course of great price, being in fact a purple sapphire, but not one jeweller- in five ever saw one, any more than he has seen a rose-coloured diamond, and the stone popularly so called, with its delicious colour, as of quivering port wine, is only a rock quartz coloured purple by the presence of manganese and iron, and is obtainable in endless quantities. "Even in the last century the commoa amethyst was held in high estimation, when Queen Charlotte's neckl lee of well-matched amethysts, the most perfect ever got together, was valued at 2,000!.; at present it would not command as many shillings, so vast has been the importation .of late years of German amethysts and topazes (purple and yellow crystals of quartz), which are got in endless abundance from various parts of Hungary, Bohemia, and notably at Oberstein, where they are cut and polished by steam power, and despatched into all parts of Europe to be made up into cheap articles of jewelry. They are also found plentifully about Wicklow, in Ireland. Barhat mentions a crystal of this kind as recently brought to Paris of the vast weight of 65 kites. (about 140 lb.). When the gem was in fashion it was formerly imported largely from the East Indies, and these were light-coloured, the purple being shaded not equably, but extremely lustrous. The colour of the amethyst can be dispelled by a careful roasting in hot ashes. Hence in the last century, when it was the great desideratum of the jewellers to .obtain a suite of stones all exactly of the same tint, they were able to obtain this result by subjecting the several pieces to the heat for a greater or less time, until they were all brought to tho same shade of purple. According to modern usage this is the only gem it is allowable to wear in mourning."

The garnet, however, which is popularly and most unfairly de- spised, is of much greater value. The Guarnaccino garnet, with a sub-yellow, is a costly stone, and the " almandine," or purple garnet of Siam, sometimes fetches a high price, while even the in- ferior sorts are from their excessive hardness valuable. "Oar garnets and carbuncles, aluminous silicates coloured by iron oxide, are now supplied in vast quantities from the mines of Zablitz in Silesia, from the Tyrol, and from Hungary. These are all inferior, both in .beauty and hardness, to those from Siam, which sends stones of the richest red, tinged with yellow, besides its peculiar purple-tinted almandines. The latter also come in abundance from Ceylon ; hence their popular name of Ceylon rubies, by means of which our jewellers obtain a better price for them from the ignorant. In spite of this abundance, even now a stone of a certain size, of a fine rich tint, and free from flaws, is of considerable value, ranging from 8/. to 10/." There are some glorious jewels extant in this stone, the finest in the world being in the collection of the Duke of Marlborough. "That very intaglio to which, as Kohler justly observes, neither ancient nor modern art has ever produced an equal as regards the skill and industry displayed in the execution, The Head of the Dog Sirius' in the Marlborough collection, is engraved in a perfect Indian garnet of unusual size and beauty. The impression from this intaglio presents the head in full relief, with open jaws, the interior of the mouth represented with miraculous fidelity ; and its value still further enhanced by the legend on the collar, AI02 EllOIEL The antiquity of this work has been disputed, without much cause ; certain it is that the artist Natter, to whom it has been assigned, was far from capable of producing such a masterpiece."

We cannot follow Mr. King through his volume, and prefer therefore to condense his information on two points, both of import- ance to the public from their extreme liability to be cheated—his account of-the opal, and of the pastes by which able artists imitate all jewels. The opal, now once again among the most fashionable of stones, is composed of pure silica and water, the latter in the proportion of ten per cent., a structure which renders it very deli- cate, heat or extreme cold equally destroying it. Its strange iridescence, which Pliny thought combined the flash of every stone, proceeds from "the reflection and refraction of light in certain openings in the interior of its mass, which are not fissures, but arranged in regular directions." The water is imbibed from the .outside, the stone being porous, and therefore liable to lose its colours when the fissures on which they depend get choked with dust or grease. The stone therefore is not one which it is worth while to purchase at very high prices, as it cannot be made to descend for generations with its lustre unimpaired. Those who possess it should be careful not to let water or soap approach it, and not to expose it to any excessive heat. The gem is now prin- cipally procured from the Hungarian mines of Czervenitza and from Mexico, but purchasers must beware of the latter. "The Hun- garian opals exhibiting an uniform milkiness of surface, more or less iridescent, have from their greater density the advantage of resisting the effects of wear longer than any other sort, hence their superior value. But infinitely greater is the beauty of the Mexican when recent,, presenting an unmixed globule of green fire, like the glowworm's lamp, or a ball of phosphorus moistened with oil. Nevertheless of so porous a nature is this kind, that it becomes colourless if wetted, and changes to an opaque brown after a brief existence as a jewel, and consequently it has no value in the gem market."

Pastes or imitation stones of the best class are now almost always made in one way. The basis of all is "stress," a substance so called from the chemist who invented it, which was formerly made- from litharge, white sand, and potass, in nearly equal proportions,

but to these the Parisian makers now add a certain pi

borax, and the paste comes out with the brilliancy c41, diamond and a hardness which defies the file, the jewelleN' test. For sapphire, oxide of cobalt is mixed with the stress, 'an" for emerald, the green oxide of copper and oxide of chrome, for the beryl, antimony and the oxide of cobalt, and for garnet, anti- mony, purple magus, and oxide of manganese. The Romans often add a kind of cap made of a slice of the true jewel, the composi- tion thus resisting all external tests, and a back made of facetted crystal to impart extra brilliancy, the glue being Venice turpen- tine, which is perfectly transparent. Mr. King does not make the remark, but it is probable that in these imitations lies the chance of the next great advance in the manufacture of glass, as there seems no final reason why " stress " should not be produced on a great scale, so as to give us, for example, tables of engraved beryl, not, it is true, real, but as hard as crystal, and durable almost for ever. The Roman pastes, for instance, have lasted down to our own time, scarcely more injured by age than the true gem would have been. They had a special facility in imitating lapis-lazuli. "In such is to be seen the finest paste cameo known (in the glass department of the British Museum), a three-quarter figure of Bonus Eventus (so inscribed) holding a cornucopia. The slab is about eight inches square, and the figure, which is in half relief, has been carefully gone over with the tool after the manner of a cameo in stone."

Mr. King's book, a massive octavo of 440 pages, is full of in- formation like this, of illustrations from classical reading, and of corrections of the popular stories, which he usually tests by the original authority. If in his next edition,he will re-write his article on pearls, which is very deficient in information, extend his chapter on prices until it becomes of real value to the ignorant, and add some facts about Oriental gems, particularly the extra- ordinary intaglios discovered in Scinde, in which the design is covered on all sides by the gem, which nevertheless is apparently solid, he will produce a book without a rival in its own depart- ment, and .which will probably endure, no man in the trade possess- ing his varied knowledge of glyptic art, and no man out of it being able to give so many practical facts.