mineral

Fluorite

Fluorite (Calcium Fluoride - CaF2)

Hardness: 4 on Mohs scale; Color: typically blue, green, or purple (shown as light blue/teal); Luster: vitreous; Crystal system: Cubic; Cleavage: Perfect octahedral; Specific gravity: 3.175–3.56.

Hardness: 4 on Mohs scale
Color: typically blue, green, or purple (shown as light blue/teal)
Luster: vitreous

Identified April 9, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: typically blue, green, or purple (shown as light blue/teal); Luster: vitreous; Crystal system: Cubic; Cleavage: Perfect octahedral; Specific gravity: 3.175–3.56.

Formation & geological history

Formed through hydrothermal activity in veins alongside lead and silver ores, or in vugs in limestone and dolomite. It can be found in a wide variety of geological ages from Precambrian to recent.

Uses & applications

Used as a flux in steel making, in the manufacture of opalescent glass, as an ingredient in enamel for cooking utensils, and for hydrofluoric acid production. High-quality specimens are used in lapidary work and jewelry.

Geological facts

Fluorite is where the term 'fluorescence' originated, as many specimens glow under ultraviolet light. It is often referred to as 'the most colorful mineral in the world'.

Field identification & locations

Identify by its hardness (can be scratched by a knife but not a penny) and its octahedral cleavage. It is commonly found in China, Mexico, South Africa, and the USA (Illinois/Kentucky).