mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: Yellow (in this specimen), can be purple, green, or blue; Luster: Vitreous; Crystal system: Isometric (cubic/octahedral); Cleavage: Perfect octahedral; Specific gravity: 3.18

Hardness: 4 on Mohs scale
Color: Yellow (in this specimen), can be purple, green, or blue
Luster: Vitreous

Identified July 15, 2026More mineral →

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Physical properties

Formation & geological history

Formed in hydrothermal veins, often associated with metallic ores like lead and silver. It can also occur in sedimentary rocks such as limestone or in some igneous rocks like granite pegmatites.

Uses & applications

Used as a flux in steel making, in the manufacture of hydrofluoric acid, in high-performance telescopes and camera lenses, and widely as a decorative gemstone or mineral specimen.

Geological facts

Fluorite was the first mineral for which the phenomenon of fluorescence was named, as many specimens glow under ultraviolet light. It is also known as 'the most colorful mineral in the world'.

Field identification & locations

Identified in the field by its octahedral cleavage (it can be broken into 8-sided shapes), its relatively low hardness (can be scratched by a knife), and its vitreous luster. Commonly found in China, Mexico, and the USA (Illinois/Kentucky).