mineral

Fluorite (often called Rainbow Fluorite or Purple-Green Fluorite)

Calcium Fluoride (CaF2)

AI-generated identification · may be incorrect

Hardness: 4.0 on Mohs scale (can be scratched by a knife). Color: Banded purple, blue, and green. Luster: Vitreous (glassy). Crystal structure: Isometric/Cubic, though this specimen shows octahedral cleavage. Cleavage: Perfect in four directions forming octahedrons. Specific Gravity: 3.18.

Hardness: 4
Color: Banded purple, blue, and green
Luster: Vitreous (glassy)

Identified March 11, 2026More mineral →

Explore Fluorite (often called Rainbow Fluorite or Purple-Green Fluorite) in the encyclopedia →

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Physical properties

Formation & geological history

Formed through hydrothermal activity, often filling veins in limestone or dolomite or as an accessory mineral in igneous rocks like granite. Common in deposits ranging from Paleozoic to Tertiary ages.

Uses & applications

Industrial use as a flux in steel making and aluminum production; used in the manufacture of high-quality lenses for cameras/telescopes. Popular in jewelry (as beads/pendants) and for ornamental carvings/metaphysical collecting.

Geological facts

Fluorite is the origin of the word 'fluorescence' because many specimens glow under UV light. It is often referred to as '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-directional cleavage (octahedron shape), soapy feel compared to quartz, and its ability to be scratched by metal but not by a fingernail. Found globally but major deposits occur in China, Mexico, and the Illinois-Kentucky district in the USA.