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Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (CaCO 3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on the Mohs scale of mineral hardness, based on scratch hardness comparison. Large calcite crystals are used in optical equipment, and limestone composed ...
The mineral is weakly piezoelectric and pyroelectric, meaning it produces a weak electric charge when it's rubbed or heated, hence the name analcime. [3] Other characteristics include the fact that the mineral can have a blueish white fluorescence when inspected under short UV light, and a creamy white-yellow one inspected under long UV light.
Construction marble is a stone which is composed of calcite, dolomite or serpentine that is capable of taking a polish. [20] More generally in construction , specifically the dimension stone trade, the term marble is used for any crystalline calcitic rock (and some non-calcitic rocks) useful as building stone.
Calcite alabaster: The tomb of Tutankhamun (d. 1323 BC) contained a practical objet d’art, a cosmetics jar made of Egyptian alabaster, which features a lid surmounted by a lioness (goddess Bast). Alabaster is a mineral and a soft rock used for carvings and as a source of plaster powder.
The typical cap rock is a salt, topped by a layer of anhydrite, topped by patches of gypsum, topped by a layer of calcite. [8] Interaction of anhydrite with hydrocarbons at high temperature in oil fields can reduce sulfate (SO 2– 4) into hydrogen sulfide (H 2 S) with a concomitant precipitation of calcite. [9]
As a type of calcite, Iceland spar can be used in construction as a building material in cement and concrete. Its high purity and brightness make it an ideal filler in paints and coatings. [54] In metallurgy, calcite acts as a flux to lower the melting point of metals during smelting and refining. [55]
Fossil skeletal parts from extinct belemnite cephalopods of the Jurassic – these contain mineralized calcite and aragonite.. Biomineralization, also written biomineralisation, is the process by which living organisms produce minerals, [a] often resulting in hardened or stiffened mineralized tissues.
Aragonite is a carbonate mineral and one of the three most common naturally occurring crystal forms of calcium carbonate (Ca CO 3), the others being calcite and vaterite.It is formed by biological and physical processes, including precipitation from marine and freshwater environments.