mineral

Fluorite

Calcium Fluoride (CaF2)

Hardness: 4. Color: Typically green, purple, yellow, or blue. Luster: Vitreous. Crystal structure: Isometric (cubic or octahedral). Cleavage: Perfect octahedral. Specific Gravity: 3.18.

Hardness: 4
Color: Typically green, purple, yellow, or blue
Luster: Vitreous

Identified June 28, 2026More mineral →

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Physical properties

Hardness: 4. Color: Typically green, purple, yellow, or blue. Luster: Vitreous. Crystal structure: Isometric (cubic or octahedral). Cleavage: Perfect octahedral. Specific Gravity: 3.18.

Formation & geological history

Formed in hydrothermal veins often alongside metallic ores like lead and silver, or in hot spring deposits and carbonate rocks. It is found in geological settings ranging from Paleozoic to more recent era deposits.

Uses & applications

Used as a flux in steel making, in the production of hydrofluoric acid, in high-performance telescopes and camera lenses, and as a popular semi-precious gemstone.

Geological facts

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

Field identification & locations

Identify by its distinctive softness (can be scratched by a pocket knife but not a copper penny) and its four directions of perfect cleavage. Found in locations like Illinois (USA), China, Mexico, and South Africa.