Abstract: A bioactive bone mineral carbonated nano-crystalline apatite is chemically bonded to a variety of substrates, including implantable prostheses. This coating is applied uniformly to substrate surfaces of varying geometry and surface textures. It is firmly secured to the substrate and encourages rapid and effective bone ingrowth. The coating is applied by immersing the substrate in an aqueous solution containing calcium, phosphate and carbonate ions. Other ions, such as sodium, potassium, magnesium, chloride, sulfate, and silicate, may optionally be present in the solution. The solution is exposed in a controlled environment when it reacts with the substrate to form the coating.