Coating bronze is a process that involves applying a thin layer of metal to a surface. The most common type of coating bronze is PATINA, which is a thin layer of corrosion that forms on the surface of the metal over time. PATINA is often used to give a unique look to metal objects and can be used to protect the metal from further corrosion. PATINA is typically created by exposing the metal to air and moisture, which causes the metal to oxidize and form a protective layer.