Wash your item in soapy water, gently scrubbing with scrubber-side of sponge to remove any accumulated dirt (crusty, sticky or mysterious). Dry the item thoroughly. Once you have done that, you should be left with two kinds of stuff to clean off: a blue-green patina (coating) or streaks and some dark brown or black patina as well.
Pour a small amount (like 2 tbsp.) of metal polish for copper onto the item. Apply it gently with soft cloth. Remember, "gently" is the watch-word. Copper is a soft metal. Bearing down hard with any kind of abrasive polish or metal scrubber (like steel-wool, for example) can scratch the surface, remove detail and even damage the shape of your item.
Let the polish dry completely. With a new clean cloth, rub off the polish. You should see some improvement. If green and brown stains remain, repeat.
Pour a small amount of ketchup into a fresh bowl/plate. Apply it to delicate surface details, like incising, and rims or edges that do not respond well to metal polish. Use Q-tips to apply and gently rub ketchup onto hard-to-clean areas.
Leave ketchup in place for 2 to 4 minutes. Moisten a clean cloth with a little water and gently rub off ketchup (it does not need to be dried). Ketchup is a great metal cleaner and you may wish to finish your job by rubbing the whole bowl with it, to even out your work.
Wash the polished item in soapy water. Dry it thoroughly and enjoy the warm, rosy, cheerful glow.
Things You Will Need
- Metal polish for copper
- Soft rags (like pieces of an old undershirt)
- Small dish or paper plate
- Masking tape, if the copper you are polished cannot be detached easily from another surface (like hinges on a wooden box)
- Rubber gloves
- Newspaper or other covering for your work surface
- Soapy water & a soft scrubby-sponge
- Ketchup on copper produces a really strange smell.