From the time that they are immersed into a marine environment, bronze propellers are prone to attack by marine organisms, such as barnacles, coral and algae, which attach themselves to the bronze metallic surface, creating lumps on the propeller, which adversely affect its balance and cause impedance and vibration of the propeller and its boat in the water. Anti-fouling paints are either too toxic for the marine environment or lack smoothness on the surface. These problems have been overcome by polishing the propeller to prepare it for electroplating, cleansing to remove dirt and grease, electroplating with copper, followed by spraying with a standard solution (5%) of sodium hypochlorite and sodium chloride and allowing sufficient time for a reaction of the hypochlorite solution with the copper to form a firmly adhering conversion coating of basic cupric chloride. The coating is blue-green in color.