Calcite 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 is a chemical or biochemical calcium carbonate corresponding to the formula CaCO3 and belongs to the carbonate minerals. One can find it as a vein mineral in deposits from hot springs, and in caverns as stalactites and stalagmites.