Effect of K+ on the stoichiometry of carbonated hydroxyapatite obtained by the hydrolysis of monetite

The stoichiometry and the thermal stability of apatites containing K+ and CO(sub 3)(super 2-) were investigated. The apatites have been obtained by the hydrolysis of monetite. The results showed the apatites started to lose carbonate at temperatures below 400 degrees C. The predominant substitution mechanisms for the stoichiometry of the precipitated samples are discussed.