mineral

Blue fluorite

Fluorite (calcium fluoride, CaF₂)

AI-generated identification · may be incorrect

Typically transparent to translucent blue-purple with vitreous luster and cubic crystal structure; perfect octahedral cleavage, Mohs hardness 4, and specific gravity about 3.18. The blocky form and strong cleavage are characteristic, though this piece appears partly rough or cleaved.

Identified August 30, 2026More mineral →

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Physical properties

Formation & geological history

Forms mainly in hydrothermal veins and replacement deposits, often with quartz, calcite, galena, or sphalerite; specimens may range from Paleozoic to much younger mineralization. Common sources include China, Mexico, England, Spain, and the United States.

Uses & applications

Used industrially as a flux in steel and aluminum production and as a source of fluorine; attractive transparent material is cut as a gemstone or sold as a collector specimen. It is too soft for durable everyday jewelry.

Geological facts

Fluorite commonly fluoresces under ultraviolet light, sometimes blue, green, or purple. Blue color is usually caused by trace elements or irradiation-related defects.

Field identification & locations

Identify by cubic habit, vivid zoning, glassy luster, softness, and perfect cleavage; it scratches more easily than quartz and may fluoresce. Handle carefully because cleavage planes chip readily.