Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate. Calcite’s name comes from the German “calcit” coined in the 19th century from latin for limestone. The word is somewhat related to chalk. Calcite can convert to aragonite in a matter of days depending on the temperature variants. Calcite is a very widespread and well-known mineral that comes in many forms and colors. It is known for its low Mohs hardness and is very abundant in the Earth's crust. It is found in sedimentary rock. Calcite contains carbon, calcium, and oxygen which are collectively known as calcium carbonate. It is usually mined from deep underground or quarried from the surface of the Earth.