What is it and where was it formed?  Calcite is mostly found in sedimentary rock.  Calcite turns into the rock called limestone. Some limestone is made when sea creatures die and their skeletons and shells fall to the bottom of the ocean.  They pile on top of each other, push on the lower layers, and the pressure makes limestone.    All limestone starts in water.  There are places in the middle of the United States where there used to be a sea.  The water has been gone for millions of years.  Even though it’s dry now, limestone can be found there.  If you add pressure and high heat to limestone, it changes into marble, a metamorphic rock.

How and where is it mined?  Calcite is mined using quarrying or underground mining.  If the calcite is not far underground, then quarrying is used.  If it is too far underground for quarrying to work, then underground mining is used.  It is found in New Jersey [Franklin], Tennessee, Illinois, and other states of the U.S.; Mexico, Germany, India, England, and other parts of the world.

What is it used for?  Calcite/limestone is used for making glass, paper, photography, statues, building, and animal food.  The Ancient Egyptian Sphinx [below] is made of limestone.

It has calcium, carbon, and oxygen in it.