calcite

n. mineral that contains calcium carbonate

The carbonate mineral, calcite, is a chemical or biochemical calcium carbonate corresponding to the formula CaCO3 and is one of the most widely distributed minerals on the Earth's surface. It is a common constituent of sedimentary rocks, limestone in particular. It is also the primary mineral in metamorphic marble. It also occurs as a vein mineral in deposits from hot springs, and also occurs in caverns as stalactites and stalagmites. Calcite is often the primary constituent of the shells of marine organisms, e.g., plankton (such as coccoliths and planktic foraminifera), the hard parts of red algae, some sponges, brachiopoda, echinoderms, most bryozoa, and parts of the shells of some bivalves, such as oysters and rudists). Calcite represents the stable form of calcium carbonate; aragonite will change to calcite at 470°C, and vaterite, or μ-CaCO3, is less stable still.
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Noun
1. a common mineral consisting of crystallized calcium carbonate; a major constituent of limestone
(hypernym) spar
(hyponym) alabaster, oriental alabaster, onyx marble, Mexican onyx
(substance-holonym) limestone
(substance-meronym) calcium carbonate

n. calcite, mineral that contains calcium carbonate

(n.)
Calcium carbonate, or carbonate of lime. It is rhombohedral in its crystallization, and thus distinguished from aragonite. It includes common limestone, chalk, and marble. Called also calc-spar and calcareous spar.