mineral

Blue calcite (likely)

Calcite, CaCO₃

AI-generated identification · may be incorrect

Pale blue, translucent mineral with a glassy to pearly luster and prominent cleavage; Mohs hardness 3, rhombohedral crystal structure, and specific gravity about 2.71. The smoothly shaped specimen appears polished or cut, so natural crystal faces are obscured.

Identified August 11, 2026More mineral →

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Physical properties

Formation & geological history

Blue calcite forms in low-temperature hydrothermal veins, cavities, and carbonate rocks, with its color commonly caused by trace inclusions or structural defects. Calcite deposits range from ancient to recent geological ages.

Uses & applications

Used as a decorative and lapidary material, ornamental carving stone, and mineral specimen; it is generally too soft for durable jewelry or construction aggregate.

Geological facts

Calcite effervesces strongly in dilute hydrochloric acid and shows double refraction in clear pieces. Blue calcite can resemble blue aragonite, celestite, or dyed carbonate material.

Field identification & locations

Common sources include Mexico, Argentina, Brazil, Madagascar, and the United States. Confirm with a hardness test and acid reaction, avoiding damage to polished surfaces.