A coating of blue-black or black oxidized zirconium of uniform and controlled thickness on a zirconium or zirconium alloy material is accomplished through the oxidative treatment of an amorphous zirconium or zirconium alloy substrate having an altered surface roughness. An oxidized zirconium coating of uniform and controlled thickness is especially useful on orthopedic implants of zirconium or zirconium-based alloys to provide low friction, highly wear resistant surfaces on artificial joints, such as, but not limited to, hip joints, knee joints, shoulders, elbows, and spinal implants. The uniformly thick oxidized zirconium surface of controlled depth on prostheses provide a barrier against implant corrosion caused by ionization of the metal prostheses. The invention is also useful in non-articulating implant devices such as bone plates, bone screws, etc.