Calcite, Midelt Province, Morocco

A very common mineral found throughout the world in sedimentary, metamorphic, and igneous rocks. “ubiquitous mineral”. Calcite is the principal mineral in limestone and marble, two very common rocks that make up a significant portion of the Earth’s crust.

Limestone is a sedimentary rock, comprised mostly of calcite. Marble is a metamorphic rock that forms when limestone undergoes heat and pressure. Marble has been used for millennia for monuments and sculptures. The lack of porosity allows it to stand up well to weathering and erosion, as well as the freeze-thaw action. The low hardness makes it an easy stone to work with, from the pyramids to small figurines.