The properties of powder synthesized from calcium acetate and sodium hydrophosphate with the ratio [Ca 2+ ]/[PO 43-] of the starting reagents equal to 1 have been investigated. After synthesis brushite, monetite, and octacalcium phosphate were found in the powder. A substantial mass loss, equal to 26%, on heating is due to not only the decomposition of the phases found but also the removal of the byproducts, consisting of sodium acetate and acetic acid and present in the powder, of the reactions occurring when the solutions of the starting substances interact. After firing at temperatures above 900°C the phases b-Ca 2 P 2 O 7 , b-Ca 3 (PO 4 ) 2 , and Ca 10 Na(PO 4 ) 7 are found in the samples.