Fluorite (also called fluorspar) is a halide mineral composed of calcium fluoride, CaF2. It is an isometric mineral with a cubic habit, though octahedral and more complex isometric forms are not uncommon. Crystal twinning is common and adds complexity to the observed crystal habits.
Category Halide mineral
Color: Colorless, white, purple, blue, green, yellow, orange, red, pink, brown, bluish black; commonly zoned
Crystal habit Occurs as well-formed coarse sized crystals also nodular, botryoidal, rarely columnar or fibrous; granular, massive
Mohs scale hardness 4 (defining mineral)
Specific gravity 3.175–3.184; to 3.56 if high in rare-earth elements