Calcite

Calcite is a rock- forming mineral with a chemical formula of CaCO3. It is extremely common and found throughout the world in sedimentary, sedimentary, metamorphic and igneous rocks. Some geologists consider it to be a 'ubiquitous mineral' - one that is found everywhere. Calcite is the principal constituent of limestone and marble. These rocks are extremely common and make up a significant portion of Earth's crust. They serve as one of the largest carbon repositories on our planet.

The properties of calcite make it one of the most widely used minerals. It is used as a construction material, abrasive, agricultural soil treatment, construction aggregate, pigment, pharmaceutical and more.

Color: Usually white but also colorless, gray, red, green, blue, yellow, brown, orange.

Hardness: 3 on Mohs scale.