In this present study, hydroxyapatitewhichwas obtained fromcattle bones has been heat treated at temperature
400 °C and 600 °C. The microstructure after the treatment has been studied in detail using Transmission electron
microscopy (TEM) and X-ray diffraction techniques. The TEMresults indicate that natural bone consists of collagen
and hydroxyapatite nano-crystals which are needle shaped. The heat treatment influences the crystallinity
and growth of these hydroxyapatite nano-crystals known as ‘crystal maturation’ or ‘crystal ageing’.