mineral

Fluorite

Calcium Fluoride (CaF2)

AI-generated identification · may be incorrect

Hardness: 4 on Mohs scale; Color: Green, purple, clear; Luster: Vitreous; Crystal Structure: Isometric/Cubic; Cleavage: Perfect octahedral; Specific Gravity: 3.175–3.184.

Hardness: 4 on Mohs scale
Color: Green, purple, clear
Luster: Vitreous

Identified May 21, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: Green, purple, clear; Luster: Vitreous; Crystal Structure: Isometric/Cubic; Cleavage: Perfect octahedral; Specific Gravity: 3.175–3.184.

Formation & geological history

Formed in hydrothermal veins, often associated with metallic ores like lead and silver, or in sedimentary rocks like limestone via hydrothermal activity.

Uses & applications

Used as a flux in steel making, in the production of hydrofluoric acid, in high-performance telescopes/camera lenses, and as a popular semi-precious gemstone/collector specimen.

Geological facts

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

Field identification & locations

Identified by its octahedral cleavage, cubic crystal habit, and the fact it can be scratched by a knife but scratches a copper penny. Commonly found in China, Mexico, and the USA (Illinois/Kentucky).