mineral

Calcite

Calcium Carbonate (CaCO3)

Hardness: 3 on Mohs scale; Color: White, colorless, yellow, orange, brown, pink; Luster: Vitreous to pearly; Crystal structure: Trigonal; Cleavage: Perfect in three directions, rhombohedral; Specific gravity: 2.71

Hardness: 3 on Mohs scale
Color: White, colorless, yellow, orange, brown, pink
Luster: Vitreous to pearly

Identified August 4, 2026More mineral →

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Physical properties

Formation & geological history

Formed in sedimentary environments through the precipitation of calcium carbonate from water, as well as in hydrothermal veins and metamorphic marble. Geological age ranges from Precambrian to recent.

Uses & applications

Used in construction (limestone and marble production), agriculture (soil conditioning), manufacturing of cement and lime, and optical equipment.

Geological facts

Calcite exhibits strong double refraction (birefringence), where objects viewed through clear crystals appear doubled. It is the primary constituent of limestone and marble.

Field identification & locations

Easily identified by its characteristic rhombohedral cleavage and strong effervescence (fizzing) when exposed to weak hydrochloric acid. Found worldwide in sedimentary rock formations.