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	Fluorite, in the colored transparent varieties, is desig­nated as false ruby, emerald, sapphire, topaz, amethyst, etc. Thirty years ago many specimens of the green variety were found at Muscalonge Lake, St. Lawrence County, N. Y., where the mineral was taken out from a vein which ran under the lake ; and in the autumn of 1888, an immense cavity lined with large cubic crystals of green fluorite was discovered at Macomb. This furnished groups measuring nearly two feet across and single composite crystals nearly a foot across, in all, several tons of fine crystals. The largest deposits in the United States are at Rosiclaire, Shawneetown, and Elizabethtown, Hardin County, 111., and some thousands of tons are annually mined there, crystals of the richest purple, yellow, red, rose-colored, green, and other shades being very common. It differs from English FLUORITE
	fluorite in that the crystalline faces in nearly all the specimens are dull, and the colors show only by transmitted light. Crys­tals a foot across were observed here twenty years ago dur­ing the workings of the Rosiclaire lead mine. In the mounds of this region it has occasionally been found shaped into orna­ments by the hand of prehistoric man. This is the only instance that is known of its being used as an ornament. The amount mined here for the arts amounts to over $15,000 a year. On the Cumberland River, Tenn., and at Pike's Peak, Col., some fine crystals of a blue-green fluorite have been found ; also yellow crystals in the géodes of the limestone at St. Louis, Mo. One of the most remarkable varieties of this mineral is a chlorophane from the microlite localities at Amelia Court House, Va., which has been described by W. M. Fontaine,1 who also noted the brilliancy of the phosphorescent light that it gives out at a low 1 Am. J. Sci. III., Vol. 25, p. 330, May, 1883 Minerals in Amelia County, Va