mineral

Fluorite

Fluorite (Calcium Fluoride - CaF2)

Hardness: 4 on Mohs scale; Color: Purple, green, blue, yellow, or colorless; Luster: Vitreous (glassy); Crystal Structure: Isometric (cubic or octahedral); Cleavage: Perfect octahedral in four directions; Specific Gravity: 3.18

Hardness: 4 on Mohs scale
Color: Purple, green, blue, yellow, or colorless
Luster: Vitreous (glassy)

Identified March 23, 2026More mineral →

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Physical properties

Formation & geological history

Primarily formed in hydrothermal veins where it often associates with metallic ores like lead and silver. It can also be found in vugs within sedimentary rocks. Its formation spans various geological ages from the Precambrian to the present.

Uses & applications

Industry: Flux in steel making, hydrofluoric acid production, and aluminum smelting. Construction: Ornamental stone. Jewelry: Used as a semi-precious stone, though soft and fragile. Collecting: Highly prized by mineral collectors for its vibrant colors and transparency.

Geological facts

Fluorite is the mineral from which the term 'fluorescence' was derived, as many specimens glow under ultraviolet light. It is often referred to as 'the most colorful mineral in the world.'

Field identification & locations

Identify in the field by its distinct cubic crystal shapes, its relatively low hardness (can be scratched by a steel knife but not a copper penny), and its perfect four-way cleavage. Common locations include Illinois (US), China, Mexico, and England.