mineral

Fluorite (Purple/Blue variety)

Calcium Fluoride (CaF2)

Hardness: 4.0 on Mohs scale; Color: typically purple, blue, or green in mass; Luster: Vitreous (glassy); Crystal Structure: Isometric/Cubic; Cleavage: Perfect octahedral in four directions; Specific Gravity: 3.18.

Hardness: 4
Color: typically purple, blue, or green in mass
Luster: Vitreous (glassy)

Identified March 27, 2026More mineral →

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Physical properties

Formation & geological history

Formed as a hydrothermal mineral in veins, typically through the cooling of mineral-rich hot water in limestone cavities or as a byproduct in ore deposits. Found in geological ages ranging from Precambrian to Cenozoic.

Uses & applications

Used as a flux in steel and aluminum smelting; manufacturing of high-purity hydrofluoric acid; opalescent glass production; and widely used for ornamental carvings, jewelry, and gemstone collecting.

Geological facts

Fluorite exhibits the physical phenomenon of fluorescence, where it glows under UV light. It is often called 'the most colorful mineral in the world' due to the wide range of hues caused by chemical impurities.

Field identification & locations

Identify in the field by its 4.0 hardness (can be scratched by a steel knife but not a copper penny) and its characteristic four-way cleavage. Commonly found in Illinois (USA), China, Mexico, and England (Blue John variety).

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