The other four natural isotopes, 42, 43, 46, 48Ca, are significantly rarer, each comprising less than 1% of natural calcium. The four lighter isotopes are mainly products of oxygen-burning and silicon-burning, leaving the two heavier ones to be produced via neutron capture.
Calcium carbonate is a common substance found in rocks and shells. It's a white, powdery compound made up of calcium, carbon, and oxygen. People use it in various products, like chalk, toothpaste, and antacids. In nature, it forms limestone and marble.

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View All Products. By Health Specialty. Beauty.Calcium: Calcium supplementation is utmost essential, especially during pregnancy. It reduces pregnancy complications and thus ensures normal pregnancy and gestation period.