mineral

Fluorite in Host Rock

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: Purple, violet, and white; Luster: Vitreous to dull; Crystal structure: Cubic or octahedral; Cleavage: Perfect octahedral; Specific gravity: 3.175–3.184.

Hardness: 4 on Mohs scale
Color: Purple, violet, and white
Luster: Vitreous to dull

Identified June 3, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: Purple, violet, and white; Luster: Vitreous to dull; Crystal structure: Cubic or octahedral; Cleavage: Perfect octahedral; Specific gravity: 3.175–3.184.

Formation & geological history

Formed via hydrothermal activity where hot, fluorine-rich fluids circulate through fractures in limestone or other host rocks. Common in hydrothermal veins and associated with lead and silver ores.

Uses & applications

Used as a flux in steel making, in the manufacture of hydrofluoric acid, in high-performance telescopes and camera lenses, and as a popular semi-precious gemstone for jewelry and décor.

Geological facts

The term 'fluorescence' is derived from fluorite, as many specimens glow under ultraviolet light. It is often called 'the most colorful mineral in the world' due to its wide range of hues caused by impurities.

Field identification & locations

Identify in the field by its distinct cubic cleavage, relative softness (it can be scratched by a knife but not a copper penny), and purple coloration. Commonly found in China, Mexico, South Africa, and the USA (Illinois/Kentucky district).