Calcite
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Description
Calcite is a common and widespread mineral, often forming in a vast array of crystal habits and aggregates, typically appearing as white to colorless rhombohedral crystals or massive forms. It is characterized by its perfect rhombohedral cleavage and relatively low hardness.
Geological Context
Calcite is a primary component of sedimentary rocks like limestone and marble, formed from the accumulation of marine organism shells or chemical precipitation. It also occurs in hydrothermal veins, igneous rocks, and as a secondary mineral in many environments.
