mineral

Yellow Fluorite

Calcium fluoride (CaF2)

Hardness: 4 (Mohs scale), Color: Yellow/Golden, Luster: Vitreous (glass-like), Crystal System: Isometric (cubic), Cleavage: Perfect octahedral, Specific Gravity: 3.17-3.18

Identified May 24, 2026More mineral →

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Physical properties

Hardness: 4 (Mohs scale), Color: Yellow/Golden, Luster: Vitreous (glass-like), Crystal System: Isometric (cubic), Cleavage: Perfect octahedral, Specific Gravity: 3.17-3.18

Formation & geological history

Formed in hydrothermal veins through cooling fluids rich in fluorine and calcium, often associated with lead and zinc ores in limestone or as a late-stage mineral in granitic pegmatites.

Uses & applications

Used as a flux in steel making, in the production of hydrofluoric acid, in the manufacture of high-clarity optical lenses, and as a popular semi-precious gemstone for jewelry and décor.

Geological facts

Fluorite is known as the 'most colorful mineral in the world' and is the namesake for the phenomenon of fluorescence; many yellow specimens glow blue-violet under UV light.

Field identification & locations

Identify in the field by its distinct cubic cleavage, vitreous luster, and its ability to be scratched by a steel knife but not a copper penny. Found globally in places like China, Mexico, Spain, and Illinois, USA.