mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4 on the Mohs scale. Color: Translucent light blue to greyish blue with soft banding. Luster: Vitreous (glass-like). Crystal Structure: Isometric (cubic). Cleavage: Perfect octahedral in four directions. Specific Gravity: 3.18.

Hardness: 4 on the Mohs scale
Color: Translucent light blue to greyish blue with soft banding
Luster: Vitreous (glass-like)

Identified July 27, 2026More mineral →

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Physical properties

Formation & geological history

Forms via hydrothermal activity in veins alongside metallic ores, or within pegmatites and limestones as warm, fluorine-rich fluid crystallizes during cooling.

Uses & applications

Used as a flux in steelmaking and aluminum processing, source of fluorine gas for fluorochemicals, and widely collected as tumbled gemstones and ornamental pieces.

Geological facts

Fluorite exhibits fluorescence, glowing vivid purple-blue under ultraviolet light—a property named directly after this mineral. Its distinct soft hardness makes it prone to scratching easily.

Field identification & locations

Can be identified by its softness (easily scratched by a copper penny or steel nail), distinct cleavage planes, cubic shape when raw, and color zoning/banding. Commonly found in China, Mexico, South Africa, and the USA (Illinois/Kentucky district).