Ch. 3: Corundum Gems

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	CORUNDUM GEMS.	19

	4 x 2 x 1-1/4 inches; part of it is transparent, and several very fine gems could be cut from it, see Plate XII. Another locality in the same county, interesting, though less prominent, is the Mincey mine on Ellijay (properly Elegee) Creek, about 2-1/2 miles northeast of Corundum Hill. Some good ruby corundum occurs here, together with a peculiar brown or bronze variety, known locally as " pearl corundum," which shows distinct asterism, both by natural and artificial light, when the stone is cut en cabochon. In natural light these corun-dums all show a bronze luster and are somewhat similar to the cat's-eye, but in artificial light the star is more distinct. Most of the bronze corundum is in rough crystals, but some have been found that have the prismatic faces smooth and well developed, and these are often dark, almost black, in color. One crystal of this dark kind, found some years ago, yielded gems 2/3 of an inch in diameter. A similar asterism has been noticed in many of the rubies and sapphires from Cowee Valley, and at several other points in the State. According to Von Lasaulx, it is sometimes produced by rifts due to the basal parting. These rifts when examined with the microscope, are seen to be very thin, sharp and rectilinear, and are parallel to the edge between the prism and the base. In other cases asterism is undoubtedly due to rutile or other minute crystals enclosed in the corundum, intersecting each other at an angle of 60°, or in some similar systematic positions. At the Cullakenee mine, Buck Creek, in Clay County, masses of emerald to grass-green amphibolite (also called smaragdite) are found, through which are disseminated particles of pink and ruby corundum, from the size of a pea to some as large as hickory nuts. The corundum is not of gem quality, but the combination of the green and pink makes very beautiful specimens, and as the rock is hard enough to take a good polish, it might furnish a decorative or ornamental stone of some value. It has been introduced for such purposes under the name of ruby matrix. A similar association of green amphibolite with corundum, sometimes pink and sometimes dark blue, is found near Elf post-office, on Shooting Creek, in the same county. Other corundum localities in Clay County are the Foster mine, near the headwaters of the north fork of Shooting Creek, and the Herbert mine on Little Buck Creek. Of late much attention has been aroused by the discovery of rich ruby corundum in small distinct crystals of a different character from any others found in the State, and in a different rock. These have been known as the Cowee rubies, from the locality in the Cowee valley, in Macon County. It has seemed as though here, at last, true gem rubies, equal to those of Burma, had been really found, and much interest has been felt in

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