The invention refers to a material which is chemically long-term stable in
a neutral or slightly acid environment and which can be used both as
bioactive bone replacement material, e.g. in the form of a coating applied
onto metallic prosthesis sticks by thermal spraying, and as substrate
material in biotechnology, e.g. in the form of a ceramic sheet. According
to the invention, said material comprises 15-45% by weight CaO, 40-45% by
weight P.sub.2 O.sub.5, 10-40% by weight ZrO.sub.2 and fluoride, said
material further comprises two crystalline phases being apatite and
calcium zirconium phosphate, and a secondary glass phase. Said material
has a very high chemical long-term stability, compared to known materials
which can also be produced by means of a melting process.