mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: Purple, green, clear (this specimen shows deep purple); Luster: Vitreous; Crystal structure: Isometric (often cubic or octahedral); Cleavage: Perfect octahedral.

Hardness: 4 on Mohs scale
Color: Purple, green, clear (this specimen shows deep purple)
Luster: Vitreous

Identified July 5, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: Purple, green, clear (this specimen shows deep purple); Luster: Vitreous; Crystal structure: Isometric (often cubic or octahedral); Cleavage: Perfect octahedral.

Formation & geological history

Formed through hydrothermal activity in veins alongside lead and silver ores, or in sedimentary environments by limestone replacement.

Uses & applications

Used in metallurgy as a flux (steelmaking), manufacture of hydrofluoric acid, high-clarity camera lenses, and as a popular collector specimen.

Geological facts

The term 'fluorescence' is derived from fluorite, as many specimens glow under ultraviolet light. It is also the only common mineral that exhibits four directions of perfect cleavage.

Field identification & locations

Identify by its purple-to-green zoning, softness (can be scratched by a knife but not a penny), and its tendency to break into triangle-faced octahedrons.