fluorite

/floor"uyt, flawr"-, flohr"-/, n.

a common mineral, calcium fluoride, CaF₂, occurring in green, blue, purple, yellow, or colorless crystals, usually in cubes: the principal source of fluorine, used also as a flux in metallurgy and for ornament. Also called fluor, fluorspar, fluor spar.

[1865-70; < It; see FLUOR-, -ITE¹]

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or fluorspar

Common halide mineral, calcium fluoride (CaF₂); the principal fluorine mineral.

Fluorite occurs most commonly as a vein mineral and is often associated with lead and silver ores; it also occurs in cavities, sedimentary rocks, pegmatites, and hot-springs areas. It is widespread in China, South Africa, Mongolia, France, Mexico, Russia, and the central U.S. Fluorite is used in the manufacture of steel, aluminum fluoride, artificial cryolite, and aluminum. It is used in glassmaking, in iron and steel enamelware, in the production of hydrofluoric acid, in the refining of lead and antimony, and (as a catalyst) in the manufacture of high-octane fuels.

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▪ mineral

also called  Fluorspar,  

 common halide mineral, calcium fluoride (CaF₂); the principal fluorine mineral. It is usually quite pure, but as much as 20 percent yttrium or cerium may replace calcium. Fluorite occurs most commonly as a glassy, many-hued vein mineral and is often associated with lead and silver ores; it also occurs in cavities, in sedimentary rocks, in pegmatites, and in hot-springs areas. It is widespread in China, South Africa, Mongolia, France, Mexico, Russia, and the central United States. Fluorite is used as a flux in the manufacture of open-hearth steel, of aluminum fluoride, of artificial cryolite, and of aluminum. It is used in opalescent glass, in iron and steel enamelware, in the production of hydrofluoric acid, in the refining of lead and antimony, and in the manufacture of high-octane fuels (as a catalyst). Because of its low index of refraction and low dispersion, clear, colourless fluorite of optical quality is used for apochromatic lenses. At one time blue john, a variety from Derbyshire, Eng., was widely used in ornamental vases and other objects. For detailed physical properties, see halide mineral (table).

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