calcium is known as
Calcium Calcium is most well known to serve as a major building block of bone in the human body, with there being anywhere from 1-2 kg of calcium in the human body that is 99% localized to bone tissue (skeleton and teeth). The calcium tends to be stored in the form of hydroxyapatite crystals (Ca 10 (OH) 2 (PO 4) 6) formed by bone cells known as osteoblasts.