644 



PRECIOUS STONES. 



chromate of potash that under the continuous 

 action of fire for fifty hours yields a porous and 

 friable gangue in the crucible containing rubies 

 which were separated from it by washing. 



Artificial Emeralds. Hautefeuille and Per- 

 ry, two French chemists, have succeeded in pro- 

 ducing very beautiful crystals of emeralds by 

 fusing silica, alumina, and glucina containing 

 traces of oxide of chromium with the acid ma- 

 lybdate of lithia. The materials were heated to 

 a temperature of 600 to 700 for fifteen days. 

 There were obtained fifteen grammes of small 

 crystals of about a millimetre, having all the 

 minerakigical and physical' characters of the 

 natural emerald. The longer the operation is 

 continued the larger the crystals become. 



Sapphire. In 1882 a very remarkable dis- 

 covery of sapphire was made in the Zenskar 

 range of the northwestern Kashmir Himalaya, 

 a short distance from the village of Machel. 

 The stones were found at the foot of a precipice, 

 where a landslide had taken place, the including 

 rocks being gneiss and mica. They were col- 

 lected by the villagers, who were attracted by 

 their beautiful colors, and so little was their 

 value realized that they were used as flints for 

 striking lights with steel. They were so abun- 

 dant at first that one writer speaks of having 

 seen about a hundredweight of them in the pos- 

 session of a single native. The price rose rapidly 

 until about 20 an ounce was paid for good speci- 

 mens, at which rate they have remained. The 

 Maharajah of Cashmere promptly sent a regi- 

 ment of sepoys to take possession of the mines, 

 and worry natives who were suspected of having 

 gems in their possession or who had any knowl- 

 edge of new localities where they could be found. 

 Several crystals were found weighing from 100 

 to 300 carats each. During the first year of the 

 discovery the Delhi jewelers are said to have 

 bought more than 20,OJO worth of these sap- 

 phires. 



Pearls. Pearls have never been so popular 

 or commanded such high prices as in recent 

 years. At present nothing is considered more 

 desirable than the pearl, on account of its purity 

 and subdued beauty. This unusual request has 

 greatly stimulated the search for them, especially 

 on the western coast of Australia, the Thursday 

 island, the Sooloo Archipelago, in Ceylon, and 

 the Persian Gulf, and also along the coast of 

 Lower California. The demand includes pearls 

 of all colors except the inferior yellow. Fine 

 black pearls from Lower California have been in 

 great request, single ones bringing as much as 

 $8,000. With these black pearls are found many 

 beautiful gray and grayish-brown pearls. The 

 different fisheries of the world produce $1,000,000 

 worth annually, of which those in California yield 

 about one sixth. Kentucky, Tennessee, and Texas 

 have given us over $10,000 worth of pearls a 

 year ; their remarkable fresh-water pearls, espe- 

 cially the pink ones, are unrivaled for delicacy 

 of tint. Fancy-colored pearls have been colored 

 by artificial means. 



Opal. When it became generally known that 

 Queen Victoria was partial to the opal, the old 

 and stubborn superstition concerning it slowly 

 yielded xintil that gem has now its share of pop- 

 ular favor. Many of those imported are of the 

 fine Hungarian variety. Mexican fire opals are 



much more common, and come from mines on 

 the Hacienda Esperanza, near Querearo. It is 

 believed that a demand of 100,000 stones a year 

 could be supplied without raising the price per- 

 ceptibly. The opal mines of Dubreck, Hungary, 

 yield the Government a revenue of $0,000 annu- 

 ally. About fifteen years ago a new and very 

 interesting variety of opal was brought from 

 Baricoo river, Queensland, where it was found in 

 a highly ferruginous jasperlike matrix, some- 

 times apparently as a nodule, and then again in 

 brilliant colored patches or in specks affording 

 a sharp contrast with the reddish-brown matrix, 

 which admits of high polish and breaks with 

 conchoidal fracture. Many of these stones are 

 exceedingly brilliant. They are known as harle- 

 quin opals, and their color is somewhat yellow 

 as compared witji the Hungarian stone, although 

 not less brilliant. The rich ultramarine blue 

 opal is peculiar to this locality. A company 

 capitalized at 200,000 was formed, and the 

 gems are mined extensively. Many curious lit- 

 tle cameolike objects are made by cutting the 

 matrix and the opal together. 



Fancy Stones. The gem and mineralogical 

 collections contain a large series of stones that 

 are hard, of rich color, and are now known as 

 "fancy stones," and by the French as pierres de 

 fantasie. Considerable interest has now cen- 

 tered in these fancy stones. The Duke of Con- 

 naught gave his bride a cat's-eye engagement 

 ring, and this made that stone fashionable and 

 increased its value. The demand soon extended 

 to Ceylon, where the true chrysoberyl cat's-eye is 

 found, and stimulated the search for it there. In 

 the chrysoberyl cat's-eye the effect is the result 

 of twinning of the crystal, or of a deposit be- 

 tween its crystalline layers of other minerals iff 

 microscopic inclusions. If the stone be cut 

 across these layers, en cabochon, or carbuncle 

 cut, a bright line of light will be condensed on 

 the domelike top of the stone. In searching for 

 these chrysoberyl cat's-eyes, there have been 

 found a series of chrysoberyls of deep golden, 

 light yellow, yellow green, sage green, dark 

 green, yellowish brown, and other tints that 

 weigh from 1 to 100 carats each, and rank next 

 to the sapphire in hardness. It was found that 

 the darker leaf-green or olive-green stones pos- 

 sessed the dichroitic property of changing to 

 columbine red by artificial light, the green being 

 entirely subdued and the red predominating. 

 They were alexandrites, a gem that had formerly 

 been found only in Siberia, and there of poor 

 quality. A perfect gem of 1 carat was a rar- 

 ity. Here, however, fine gems under 4 carats 

 were common, and an exceptional one weighing 

 67 carats was found. Among this alexandrite 

 variety a few hav-e been found which include the 

 characteristics of the cat's-eye. and hence were 

 named the alexandrite cat's-eye. Moonstones 

 from the province of Candy, Ceylon, were 

 brought to light by this search for cat's-eyes. 

 Probably 100,000 of these stones have been 

 mounted in this country. They vary in size 

 from one eighth of an inch to nearly two inches 

 in length and one inch in thickness, and many 

 of them surpass anything hitherto known of 

 their kind in beauty and size. Those that dis- 

 play the chatoyant white and the hazy blue color 

 are especially beautiful. The demand for cat's- 



