mineral

Fluorite

Calcium Fluoride (CaF2)

AI-generated identification · may be incorrect

Hardness: 4 on Mohs scale; Color: Green, purple, blue, or yellow; Luster: Vitreous; Crystal system: Isometric/Cubic; Cleavage: Perfect octahedral; Specific gravity: 3.18.

Hardness: 4 on Mohs scale
Color: Green, purple, blue, or yellow
Luster: Vitreous

Identified July 4, 2026More mineral →

Explore Fluorite in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 4 on Mohs scale; Color: Green, purple, blue, or yellow; Luster: Vitreous; Crystal system: Isometric/Cubic; Cleavage: Perfect octahedral; Specific gravity: 3.18.

Formation & geological history

Forms primarily in hydrothermal veins, often as a gangue mineral associated with metallic ores. It can also occur in sedimentary rocks like limestone and some igneous rocks.

Uses & applications

Used as a flux in steel making, in the manufacture of hydrofluoric acid, in high-performance telescopes/camera lenses, and as a popular ornamental stone and collector specimen.

Geological facts

Fluorite is famous for its wide range of colors and was the first mineral in which the phenomenon of fluorescence was studied and named. It glows under ultraviolet light.

Field identification & locations

Identify by its 4-way octahedral cleavage, its relatively low hardness (can be scratched by a pocket knife), and its cubic crystal habit. Common in Illinois (USA), China, and Mexico.