Hydroxyapatite is the most stable form of calcium phosphate and is slightly soluble in water. Hydroxyapatite is the man inoganic component of mammalian hard tissue such as bones and teeth. In this research, it has been synthesized using (NH4)2HPO4 as a source phosphate (P) and Ca(NO3)2 with Ca(OH)2 as source calcium (Ca) by comparison of the molar ratio Ca/P (1.67) which is calcined at 900°C w…