Fluorite
Image: “Jon Zander (<a href="//commons.wikimedia.org/wiki/User:Digon3" title="User:Digon3">Digon3</a>)" (CC BY-SA 3.0)
Mineral NameFluorite
Chemical FormulaCaF₂
Mohs Hardness4
Crystal Systemcubic
Lustervitreous
Streak Colorwhite
Cleavageperfect octahedral (four directions)
Fractureconchoidal
Specific Gravity3.18
Colorsyellow
Transparencytransparent to translucent
Type LocalityWorldwide, notable localities include Illinois (USA), Derbyshire (England), Mexico, China, Germany
Mineral GroupHalides
Usesflux in steelmaking, source of fluorine for hydrofluoric acid, optical lenses, jewelry, collector specimens
Associated Mineralsquartz, calcite, barite, galena, sphalerite
Raritycommon
Description
This image displays a roughly 1.5-inch (4 cm) fragment of yellow fluorite, exhibiting a translucent quality and a somewhat crystalline, fractured surface.
Geological Context
Fluorite commonly forms in hydrothermal veins, often associated with metallic ore deposits, and can also be found in granites, pegmatites, and some sedimentary rocks.
