Arizona republican., 1894-11-06
PRECIOUS STONES.
interesting Facts About Some of
 the Worlds Rare Gems.
Beautiful Agates and Crystals Known to the AncieDts-The Diamond Not the Most Valued, as Is Com
 monly Supposed.

 supreme as the most precious substance in the world, says the New York Ad- vertiser So much many persons know, but few are aware that rubies. sapphires, oriental amethysts and to- pages are all practically the same gem. They are corundum, or crystallized alumina, but with infinite diversities of coloring and infinite different values. It is curious, but true, that ruby is only red sapphire, and sapphire only blue ruby.
 The finest ''pigeon's blood'' rubies come from Burmah, those from Siam or Ceylon being too dark or too pale, and the Montana stones being cloudy and brown. A perfect one carat specimen may cost six hundred dollars, while diamond of the finest water of the same size can be bought for one hum dred and twenty-five dollars. The rich color of the ruby, color which does not blacken like the blue of sapphire by night, is supposed to be due to trace of oxide of chromium, but this IS still moot point with chemists, and all are not even agreed as to the sap phire's velvet tinge. This latter stone is much less valuable than ruby, being found larger and more abundantly. Sapphires really present all colors, the pure white variety, when skillfully cut, being difficult to tell from diamond. This is deception dishonest jewellers not unfrequently practice to catch the unwary. Both rubies and sapphires are occasionally met with as ''star stones"-that is, opaque cabochon-cut gems showing the perfect steely rays of a star.
 The emerald is another exceedingly dear stone, surpassing the diamond in value when of good size and free from flaws Unfortunately, this gem is rare ly faultless, but, if perfect, it easily fetches five hundred dollars carat. Emerald and aquamarine, the latter a beautifully sunny sea-green stone, are identical in chemical composition, be- ing varieties of the mineral beryl with traces of different coloring matter. Bervl is found in all shades from honey yellow to the velvet green of the right emerald The aquamarine variety has lately become dear and fashionable, and rightly so, for the stone is durable and a lovely object. The late emperor ot Brazil is said to have possessed an aquamarine of over two hundred ounces troy weight. The indefinite colors of the beryl must have beer known for ages. since this gem repre- sented the doubting Thomas.
 After perfect rubies and emeralds and perhaps after great pearls, comes the diamond in value. This, too, has { range of colors, the most prized being red, blue, green, and water white, whil' brown or gray tinges are not quit so highly esteemed. The Koh-i-Noor, O one hundred and two and three-fourth carats, ranks low in point of size witt some of the worlds great stones-fo instance with the Great Mogul, tw' hundred and seventy-nine carats il weight Diamond is the hardes mineral known, brittle though it be acids do not affect it, and it is also tn only combustible gem. It has high re fractive and dispersive powers ('fre'' and some specimens become pho: phorescent by the action of light. usually occurs as an eight-sided crysta
 The name topaz is applied to thre distinct kind of stones, to the orientf topaz, which is really yello' sapphire; to the Scotch topaz, which only quartz, just as amethysts al Yiolet-colored quartz of little valu and to the Brazilian topaz, vivaciou sherry-colored gem which is the onl true topaz This latter stone takes high, brilliant polish, and it fee slippery to the touch. The rose pir topaz seen in shops is not natur color; it is obtained by subjecting u dark yellow varieties to great hea The commercial value of topaz IS e tremely fuctuating, one reason beil that light exercises bleaching effe on it.
 Another gem, beautiful and intere' ing in itself, which is occasionally SC for the true ruby, is the red zircon, al called iargoon and jacinth or hyacint Jewellers call these stones ''jacin rubies" and charge accordingly. T gem is of all colors, the pure white or being hard to distinguish from d monds, on account of their wonder. fire. Chrysolite is just as white, but is like glass compared with diamo or jargoon.
 There are two kinds of chrysobe
 used as gems. One the well-kno
 oriental cats-eye, an opaque greeni
 brown cabochon-cut stone, showing
 steely flash or line like silver wire;
 other the little known but beautl
 and curious alexandrite. This unit
 gem is olive or pistachio green by d
 light, and it has the remarkable pl