Image: Arenamontanus (CC BY 2.0)
cubiccommonHalides
Fluorite
CaF2
The image shows a translucent to transparent fluorite crystal, exhibiting distinct purple and colorless banding, characteristic of its octahedral cleavage. The specimen casts a shadow, highlighting its crystalline form and internal clarity.
Fluorite Physical Properties
Mohs Hardness
4Crystal System
cubicLuster
vitreousStreak Color
whiteCleavage
perfect octahedral (four directions)Fracture
conchoidalSpecific Gravity
3.18Colors
purple, colorless, violetTransparency
transparentType Locality
Illinois, USA; Derbyshire, England; Naica, Mexico; Hunan, ChinaMineral Group
HalidesUses
flux in steelmaking, hydrofluoric acid production, optical lenses, jewelry, collectorAssociated Minerals
quartz, calcite, barite, galena, sphaleriteRarity
commonGeological Context
Fluorite typically forms in hydrothermal veins, often associated with metallic ores, and also occurs in pegmatites and some sedimentary rocks. It crystallizes from hot aqueous solutions rich in calcium and fluorine.
