mineral

Fluorite

Calcium fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: Multi-colored zoning (purple/green/teal); Luster: Vitreous; Crystal system: Isometric/Cubic; Cleavage: Perfect octahedral; Specific Gravity: 3.175–3.184

Hardness: 4 on Mohs scale
Color: Multi-colored zoning (purple/green/teal)
Luster: Vitreous

Identified July 21, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: Multi-colored zoning (purple/green/teal); Luster: Vitreous; Crystal system: Isometric/Cubic; Cleavage: Perfect octahedral; Specific Gravity: 3.175–3.184

Formation & geological history

Formed via hydrothermal activity in veins alongside lead and silver ores, or in limestone cavities and pegmatites. It precipitates as mineral-rich hot water cools underground.

Uses & applications

Used as a flux in steel making, as a source of hydrofluoric acid, in high-performance optical lenses, and as ornamental gemstone material.

Geological facts

Fluorite is the origin of the term 'fluorescence' because many specimens glow under UV light. It is often referred to as 'The most colorful mineral in the world'.

Field identification & locations

Identify by its characteristic purple-green color zoning and its cubic cleavage. In the field, look for its relative softness (scratches with a knife) and glassy appearance. Found globally with major deposits in China, Mexico, and the USA (Illinois).