mineral

Calcite

Calcium Carbonate (CaCO3)

AI-generated identification · may be incorrect

Hardness: 3 (Mohs scale), Color: White/Colorless, Luster: Vitreous to pearly, Crystal structure: Trigonal (rhombohedral cleavage), Specific gravity: 2.71

Identified July 4, 2026More mineral →

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Physical properties

Hardness: 3 (Mohs scale), Color: White/Colorless, Luster: Vitreous to pearly, Crystal structure: Trigonal (rhombohedral cleavage), Specific gravity: 2.71

Formation & geological history

Commonly formed in sedimentary environments as a chemical precipitate from evaporation or accumulation of marine organisms Shells. It can also form in metamorphic (marble) and igneous rocks.

Uses & applications

Used in construction as a component of cement and mortar, in agriculture for soil treatment, as an abrasive, and in the optical industry for high-grade specimens.

Geological facts

Calcite exhibits double refraction; when you look through a clear crystal, images appear doubled. It is the primary constituent of limestone and marble.

Field identification & locations

Identify in the field by its rhombohedral cleavage (breaks into slanted cubes) and its rapid effervescence when exposed to cold dilute hydrochloric acid.