A method for providing a surface finish to a metal part includes both diffusion hardening a metal surface to form a diffusion-hardened layer, and oxidizing the diffusion-hardened layer to create an oxide coating thereon. The diffusion-hardened layer can be harder than an internal region of the metal part and might be ceramic, and the oxide coating can have a color that is different from the metal or ceramic, the color being unachievable only by diffusion hardening or only by oxidizing. The metal can be titanium or titanium alloy, the diffusion hardening can include carburizing or nitriding, and the oxidizing can include electrochemical oxidization. The oxide layer thickness can be controlled via the amount of voltage applied during oxidation, with the oxide coating color being a function of thickness. An enhanced hardness profile can extend to a depth of at least 20 microns below the top of the oxide coating.