Fluorite
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Mineral NameFluorite
Chemical FormulaCaF₂
Mohs Hardness4
Crystal Systemcubic
Lustervitreous
Streak Colorwhite
Cleavageperfect octahedral (four directions)
Fracturesubconchoidal to uneven
Specific Gravity3.18
Colorspurple, green, blue, yellow, colorless
Transparencytransparent to translucent
Type LocalityWorldwide; notable localities include Illinois (USA), Weardale (England), Naica (Mexico)
Mineral Grouphalides
Usesflux in steelmaking, hydrofluoric acid production, optical lenses, jewelry, collector
Associated Mineralsquartz, calcite, barite, galena, sphalerite
Raritycommon
Description
The specimen is a dark purple, somewhat botryoidal or massive aggregate of fluorite crystals, displaying a rich, deep color on a lighter matrix.
Geological Context
Fluorite commonly forms in hydrothermal veins, often associated with metallic ores. It can also be found in pegmatites, granites, and sedimentary rocks.
