Calcium hydroxyphosphate (calcium phosphate tribasic, tribasic calcium phosphate, hydroxyapatite, HAp) is an inorganic chemical compound that is made up of calcium, hydrogen, oxygen and phosphorus. Its formula is Ca₅(OH)(PO₄)₃.Calcium phosphate tribasic
/ref> It is found in the body and as the mineral

hydroxyapatite Hydroxyapatite, also called hydroxylapatite (HA), is a naturally occurring mineral form of calcium apatite with the formula Ca5(PO4)3(OH), but it is usually written Ca10(PO4)6(OH)2 to denote that the crystal unit cell comprises two entities. ...

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Calcium compounds {{inorganic-compound-stub