by either physically or chemically removing the polymerized layers (not to be confused with the surface layer of regular oil), allowing rust to form on the now-exposed bare metal. Modern, less caustic, dish-soaps do not interact with the polymerized coatings, and therefore do not damage cookware patinas, though every effective soap will strip the protective surface-layer oils.

Knife collectors that own carbon steel blades sometimes force a patina onto the blade to help protect it and give it a more personalized look. This can be done