mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: typically green, purple, or blue; Luster: vitreous; Crystal structure: isometric/cubic; Cleavage: perfect octahedral; Specific gravity: 3.17 to 3.56.

Hardness: 4 on Mohs scale
Color: typically green, purple, or blue
Luster: vitreous

Identified June 30, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: typically green, purple, or blue; Luster: vitreous; Crystal structure: isometric/cubic; Cleavage: perfect octahedral; Specific gravity: 3.17 to 3.56.

Formation & geological history

Commonly forms in hydrothermal veins, often associated with metallic ores like lead and silver. It can also be found in vugs within limestone and dolomite through hydrothermal replacement processes.

Uses & applications

Extensively used as a flux in steelmaking (to lower melting point), in glass and enamel production, as a source for hydrofluoric acid, and as a popular semi-precious gemstone for jewelry and metaphysical collections.

Geological facts

Fluorite is famous for its fluorescence under UV light, a property named after the mineral itself. It is often referred to as 'the most colorful mineral in the world' due to the wide variety of hues caused by impurities.

Field identification & locations

Identify in the field by its softness (can be scratched by a knife but not a coin), perfection of cubic or octahedral cleavage, and glow under ultraviolet light. Major deposits are found in China, Mexico, and the Illinois-Kentucky district in the USA.