mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: typically purple, green, or blue; Luster: Vitreous (glassy); Crystal Structure: Isometric/Cubic; Cleavage: Perfect octahedral; Specific Gravity: 3.18

Hardness: 4 on Mohs scale
Color: typically purple, green, or blue
Luster: Vitreous (glassy)

Identified July 1, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: typically purple, green, or blue; Luster: Vitreous (glassy); Crystal Structure: Isometric/Cubic; Cleavage: Perfect octahedral; Specific Gravity: 3.18

Formation & geological history

Usually forms in hydrothermal veins, often associated with metallic ores like lead and silver. It can also occur in sedimentary rocks as a primary or secondary mineral.

Uses & applications

Used as a flux for smelting in the steel industry, in the production of hydrofluoric acid, as high-clarity lenses for telescopes/cameras, and for decorative jewelry or carvings.

Geological facts

Fluorite is famous for its wide range of colors and its ability to fluoresce under ultraviolet light, a phenomenon named after the mineral itself.

Field identification & locations

Identify in the field by its distinct cubic crystals and its relative softness (can be scratched by a knife but not a copper penny). It is commonly found in Germany, China, and the USA (Illinois/Kentucky).