Calcite

The unit cell of calcite

Calcite is one of the most common minerals on the Earth's surface. It is a often part of sedimentary rocks, especially limestone. It is also the primary mineral in metamorphic marble.

It is a chemical or biochemical calcium carbonate with the formula CaCO₃. It is a carbonate mineral. It can be a vein mineral in deposits from hot springs, and in caverns as stalactites and stalagmites.

Calcite Media

Crystal structure of calcite
Photograph of calcite displaying the characteristic birefringence optical behaviour
Demonstration of birefringence in calcite, using 445 nm laser
Calcite Quarry, Michigan. Original from NASA.
One of several calcite or alabaster perfume jars from the tomb of Tutankhamun, d. 1323 BC
Phase Diagram for the Calcite and Aragonite System
Ocean acidification reduces pH, which affects calcification in shelled organisms.
Calcite (Iceland spar). More info about this file and about this specimen at geocollections.info
cristaux de calcite jaune sur fluorine (=fluorite) violette
crystals of calcite, crystals of galena, crystals of pyrite : Dal'negorsk (Dalnegorsk; Tetyukhe; Tjetjuche; Tetjuche), Kavalerovo Mining District, Primorskiy Kray, Far-Eastern Region, Russia

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