mineral

Likely calcite

Calcite, calcium carbonate (CaCO₃)

AI-generated identification · may be incorrect

Pale yellow to cream, translucent, with a vitreous to pearly luster and visible cleavage faces. Calcite has trigonal crystal structure, Mohs hardness 3, and specific gravity about 2.7; the image alone cannot confirm the identification.

Identified October 8, 2026More mineral →

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Physical properties

Formation & geological history

Calcite commonly forms in sedimentary rocks from mineral-rich water or accumulated shells, and also occurs in hydrothermal veins and metamorphic marble. It has formed throughout geologic time.

Uses & applications

Used in cement and lime production, as a building stone and industrial filler, and in collections; clear optical calcite is also used for specialized optical components.

Geological facts

Calcite effervesces in dilute acid and can be scratched with a copper coin. Its strong birefringence can make text viewed through clear crystals appear doubled.

Field identification & locations

The pale color and apparent cleavage are consistent with calcite, but a hardness or acid test would help distinguish it from gypsum and other light-colored minerals. Calcite is widespread in limestone, caves, and hydrothermal veins worldwide.