The improved bone prosthesis of the invention comprises a unitary body containing an eutectic of metal pyrophosphate and refractory oxide. Preferably, the body also contains discrete particles of refractory oxide bonded together by the eutectic which serves as a matrix bonder. Moreover, the particles are preferably of the same refractory oxide, such as alumina, as is present in the eutectic and are of extended surface area for improved strength. The pyrophosphate preferably is calcium pyrophosphate so that the prosthesis is biodegradable. The prosthesis can be prepared, in accordance with the present method, by forming the eutectic, preferably a pourable mixture of the particles and the molten eutectic, and pouring the mixture into and filling a mold of a bone to be duplicated, solidifying the mold and recovering it from the mold. The surface of the prosthesis can be texturized, as by acid etching it, to increase bond ingrowth and/or tissue attachment when implanted.