mineral

Fluorite

Fluorite (Calcium Fluoride, CaF2)

Hardness of 4 on the Mohs scale, exhibits vibrant colors including purple, green, blue, and yellow, vitreous to sub-vitreous luster, isometric crystal system with perfect octahedral cleavage, and a specific gravity of around 3.18.

Identified August 3, 2026More mineral →

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Physical properties

Formation & geological history

Forms primarily in hydrothermal veins, often associated with metallic ores like lead and zinc, as well as in cavities in sedimentary rocks and carbonatites.

Uses & applications

Used widely in metallurgy as a flux, in the manufacturing of optical equipment like lenses and prisms, in the production of hydrofluoric acid, and as a popular ornamental stone and collector mineral.

Geological facts

Fluorite is the defining mineral for a hardness of 4 on the Mohs scale. It is also famous for exhibiting strong fluorescence under ultraviolet light, a phenomenon named after the mineral itself.

Field identification & locations

Easily identified by its relatively low hardness (can be scratched easily with a knife), perfect cleavage forming octahedral shapes, and often striking multi-colored banding. Commonly found in China, Mexico, South Africa, and the USA.