mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: Multi-colored (purple, green, clear); Luster: Vitreous; Crystal system: Isometric/Cubic; Cleavage: Perfect octahedral in four directions; Specific Gravity: 3.18

Hardness: 4 on Mohs scale
Color: Multi-colored (purple, green, clear)
Luster: Vitreous

Identified July 20, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: Multi-colored (purple, green, clear); Luster: Vitreous; Crystal system: Isometric/Cubic; Cleavage: Perfect octahedral in four directions; Specific Gravity: 3.18

Formation & geological history

Commonly forms in hydrothermal veins where it is deposited from mineral-rich hot fluids. It is also found in the cavities of sedimentary rocks like limestone and in some igneous environments.

Uses & applications

Used as a flux in steel and aluminum manufacturing, in the production of hydrofluoric acid, glassmaking, and high-performance telescope lenses. It is highly valued as a decorative collector mineral and in jewelry.

Geological facts

Fluorite is the origin of the term 'fluorescence' because many specimens glow under ultraviolet light. It is often called 'the most colorful mineral in the world' due to the wide variety of colors it can display.

Field identification & locations

Identify in the field by its characteristic octahedral cleavage and relatively low hardness (can be scratched by a pocket knife). Common locations include China, Mexico, South Africa, and Illinois in the USA.