mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: Purple to violet with translucent areas; Luster: Vitreous (glass-like); Crystal Structure: Isometric/Cubic, often exhibiting perfect octahedral cleavage.

Hardness: 4 on Mohs scale
Color: Purple to violet with translucent areas
Luster: Vitreous (glass-like)

Identified July 25, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: Purple to violet with translucent areas; Luster: Vitreous (glass-like); Crystal Structure: Isometric/Cubic, often exhibiting perfect octahedral cleavage.

Formation & geological history

Formed through hydrothermal activity in veins alongside lead, zinc, and silver ores, or in pegmatites and metamorphic environments.

Uses & applications

Used as a flux in steelmaking, in the production of hydrofluoric acid, optics for special lenses, and widely as a lapidary gemstone and collector specimen.

Geological facts

Fluorite gave its name to the phenomenon of fluorescence, as many specimens glow strongly under ultraviolet light due to trace impurities.

Field identification & locations

Identified by its softness (can be scratched by a steel nail), cubic crystal habits, perfect 4-way octahedral cleavage, and vitreous luster. Commonly found in Illinois (USA), China, Mexico, and South Africa.