Hydroxyapatite (HAp) was successfully produced by using recycled eggshell. The observed phases of the synthesised materials were dependent
on the mechanochemical activation method (ball milling and attrition milling). The structures of the HAp were characterized by X-ray diffraction,
scanning electron microscopy and infrared spectroscopy. Attrition milling proved to be more efficient than ball milling, as resulted nanosize,
homogenous HAp even after milling.