mineral

Fluorite (Green Fluorite)

Calcium Fluoride (CaF2)

Hardness: 4 on Mohs scale; Color: typically green, purple, or blue; Luster: vitreous (glassy); Crystal Structure: Isometric (cubic/octahedral); Cleavage: Perfect octahedral; Specific Gravity: 3.18

Hardness: 4 on Mohs scale
Color: typically green, purple, or blue
Luster: vitreous (glassy)

Identified March 22, 2026More mineral →

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Physical properties

Hardness: 4 on Mohs scale; Color: typically green, purple, or blue; Luster: vitreous (glassy); Crystal Structure: Isometric (cubic/octahedral); Cleavage: Perfect octahedral; Specific Gravity: 3.18

Formation & geological history

Fluorite occurs as a hydrothermal mineral in veins, often in association with metallic ores like lead and silver. It can be found in sedimentary rocks as a cementing material or in igneous rocks like pegmatites.

Uses & applications

Used industrially as a flux in steel making, in the manufacture of hydrofluoric acid, and for high-performance telescopes/camera lenses. In jewelry, it is used for cabochons and beads, though it is fragile. Highly popular with collectors.

Geological facts

Fluorite is the origin of the term 'fluorescence,' as many specimens glow under UV light. It is often called 'the most colorful mineral in the world' due to the wide range of hues caused by impurities.

Field identification & locations

Identify in the field by its distinct 4-way cleavage, glassy luster, and the fact it can be scratched by a steel knife but can scratch a copper penny. Common locations include China, Mexico, South Africa, and Illinois, USA.