mineral

Fluorite

Calcium fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: Purple/Violet (as shown); Luster: Vitreous/Glassy; Crystal structure: Isometric (often cubic or octahedral); Specific gravity: 3.18.

Hardness: 4 on Mohs scale
Color: Purple/Violet (as shown)
Luster: Vitreous/Glassy

Identified June 3, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: Purple/Violet (as shown); Luster: Vitreous/Glassy; Crystal structure: Isometric (often cubic or octahedral); Specific gravity: 3.18.

Formation & geological history

Formed via hydrothermal activity in veins alongside lead and silver ores, or in limestone cavities. It can range from Paleozoic to more recent geological ages depending on the deposit.

Uses & applications

Used as a flux in steel making, in the manufacture of hydrofluoric acid, in high-performance telescope lenses, and as a popular semi-precious gemstone for jewelry and carving.

Geological facts

Fluorite is famous for its wide range of colors and its property of fluorescence under UV light. It is often called 'the most colorful mineral in the world.'

Field identification & locations

Identify by the perfect octahedral cleavage and its relatively low hardness (can be scratched by a knife but not a copper penny). Commonly found in China, Mexico, and the USA (Illinois/Kentucky).