Maylinda, NiaAwaluddin, AmirYanti, Pepi Helza2016-05-022016-05-022016-05-02wahyu sari yenihttp://repository.unri.ac.id/xmlui/handle/123456789/8328The synthesis of hydroxyapatite (HAp) from seashell (Geloina coaxans) using precipitation method has been done . The seashell (Geloina coaxans) and H3PO4 were used as sources of calcium and phosphate. Molar ratio of precursor was 1.67. Product obtained was characterized using X-ray Diffraction (XRD) and FTIR. The results showed that the particle size of hydroxyapatite (HAp) using H3PO4 as precursor was 26.419 nm and degree of crystallinity was 89.90%. Analysis using FTIR revealed that hydroxyapatite (HAp) compounds have specific band of functional groups OH and PO43- in sample spectrumenGeloina coaxansHydroxyapatitePrecipitationstudent Paper Post Degree