mineral

Fluorite (Rainbow/Purple Fluorite)

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: Purple, teal, and clear color zoning; Luster: Vitreous (glassy); Crystal Structure: Isometric/Cubic with perfect octahedral cleavage; Specific Gravity: 3.175–3.184.

Hardness: 4 on Mohs scale
Color: Purple, teal, and clear color zoning
Luster: Vitreous (glassy)

Identified March 15, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal activity, often in veins or as a gangue mineral in metallic ores. Colors are caused by trace impurities or radiation damage in the crystal lattice. Found in deposits ranging from Paleozoic to Cenozoic eras.

Uses & applications

Used as a flux in steel making, in the manufacture of opalescent glass, and as a source of fluorine for hydrofluoric acid. In jewelry and collecting, it is popular for its vibrant colors and translucency, though limited by its softness.

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' because it comes in more distinct colors than any other mineral.

Field identification & locations

Identify in the field by its softness (it can be scratched by a steel knife but not a copper penny) and its characteristic octahedral cleavage. Found commonly in China, Mexico, South Africa, and Illinois, USA (where it is the state mineral).

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