mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale. Color: Green with hints of purple. Luster: Vitreous (glassy). Crystal Structure: Isometric/Cubic. Cleavage: Perfect octahedral. Specific Gravity: 3.175–3.184.

Hardness: 4 on Mohs scale
Color: Green with hints of purple
Luster: Vitreous (glassy)

Identified May 18, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale. Color: Green with hints of purple. Luster: Vitreous (glassy). Crystal Structure: Isometric/Cubic. Cleavage: Perfect octahedral. Specific Gravity: 3.175–3.184.

Formation & geological history

Formed through hydrothermal activity, often found in veins where it occurs as a gangue mineral associated with metallic ores. It typically forms in hydrothermal deposits or as an accessory mineral in igneous rocks like granite.

Uses & applications

Used as a flux in steel making, in the manufacture of opalescent glass, enamels for cooking utensils, and in the production of hydrofluoric acid. High-clarity specimens are used for optical lenses, and colorful pieces are used for jewelry and carving.

Geological facts

The word 'fluorescence' is derived from fluorite, as many specimens exhibit a strong glow under ultraviolet light. It is often referred to as 'the most colorful mineral in the world'.

Field identification & locations

Identified in the field by its distinct hardness (softer than quartz or glass) and its characteristic octahedral cleavage. Commonly found in China, Mexico, South Africa, and the USA (Illinois and Kentucky). Collectors look for well-defined cubic crystals or zoning of colors.