mineral

Likely polished fluorite or blue calcite specimen

Fluorite (CaF₂) or calcite (CaCO₃); exact identification is uncertain under blue lighting

AI-generated identification · may be incorrect

A polished blue, translucent cabochon with cloudy internal zoning and low-to-moderate luster. Fluorite has Mohs hardness 4 and cubic cleavage; calcite has hardness 3, rhombohedral cleavage, and commonly shows stronger cloudy banding.

Identified August 19, 2026More mineral →

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Physical properties

Formation & geological history

Fluorite forms in hydrothermal veins, while calcite commonly precipitates from carbonate-rich groundwater or hydrothermal fluids; specimens may range from Paleozoic to recent geological settings.

Uses & applications

Used as a decorative cabochon or collector specimen; fluorite is also an industrial source of fluorine, and calcite is widely used in cement, lime, and aggregate.

Geological facts

The intense electric-blue appearance is likely enhanced by aquarium or LED lighting and may not represent the natural color. A hardness test and acid reaction are more diagnostic than appearance alone.

Field identification & locations

Check for cubic cleavage or purple/green zoning for fluorite; calcite effervesces with dilute hydrochloric acid and is easily scratched by a copper coin. Common sources include China, Mexico, the United States, and Morocco.