mineral

Fluorite on Matrix

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: Purple and clear/white; Luster: Vitreous/glassy; Crystal structure: Isometric (cubes, octahedrons); Cleavage: Perfect octahedral; Specific gravity: 3.01-3.25.

Hardness: 4 on Mohs scale
Color: Purple and clear/white
Luster: Vitreous/glassy

Identified June 23, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: Purple and clear/white; Luster: Vitreous/glassy; Crystal structure: Isometric (cubes, octahedrons); Cleavage: Perfect octahedral; Specific gravity: 3.01-3.25.

Formation & geological history

Formed through hydrothermal processes where hot, fluorine-rich fluids circulate through host rock fractures. It is often found in mineral veins or limestone cavities.

Uses & applications

Used in steelmaking as a flux, aluminum production, and the manufacturing of hydrofluoric acid. High-quality specimens are used for jewelry, carvings, and optics (lenses).

Geological facts

Fluorite is the origin of the term 'fluorescence' because many specimens glow under ultraviolet light. It is often called the 'most colorful mineral in the world.'

Field identification & locations

Identify in the field by its distinct 4-directional cleavage and relative softness (scratched by glass but not a copper penny). Commonly found in Illinois (USA), China, and Mexico.