mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale. Color: Transparent green. Luster: Vitreous/Glassy. Crystal system: Cubic (often appearing as octahedral shards). Cleavage: Perfect octahedral in four directions.

Hardness: 4 on Mohs scale
Color: Transparent green
Luster: Vitreous/Glassy

Identified July 4, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale. Color: Transparent green. Luster: Vitreous/Glassy. Crystal system: Cubic (often appearing as octahedral shards). Cleavage: Perfect octahedral in four directions.

Formation & geological history

Formed through hydrothermal activity, typically in veins where hot, mineral-rich water flows through fractures in rocks. Common in both sedimentary environments like limestone and igneous settings.

Uses & applications

Used as a flux in steel making, in the production of hydrofluoric acid, high-clarity optical lenses, and widely collected as ornamental specimens and jewelry.

Geological facts

Fluorite was the first mineral to have the property of 'fluorescence' described, named after the mineral itself. It is often called 'the most colorful mineral in the world'.

Field identification & locations

Identify by its relatively low hardness (can be scratched by a steel knife but not a copper penny) and its classic green or purple translucent hues. Look for it in limestone quarries or mining districts.