A product comprising a copper alloy comprising a contact surface having a roughness of 6 to 14 microinches Ra. This may be produced by a method for maintaining and using a high concentration of dissolved copper on a surface of a useful article by providing a copper surface without coatings thereon which increase the wetting angle and which isolate the copper surface and which has a surface roughness between 2 and 50 micro inches Ra, so as to kill microbes thereon.
