Acidic cleaning solutions are very effective for cleaning copper. Vinegar, lemon juice and ketchup are all effective copper cleaners, especially when combined with gritty sodium-based substances.
- Make an acidic cleaning solution
- Apply the copper cleaner
- Rinse and polish
Mix 1/2 cup vinegar with 1 tablespoon of salt, or mix 1/2 cup of lemon juice with 1 tablespoon of baking soda. For large items, mix up a larger batch of cleaning solution.
Submerge the copper item in the solution and let it soak for 15 minutes. Check to see if the tarnish scrubs off easily. If it doesn't scrub away easily, let the copper item soak for up to an hour, checking it every 15 minutes.
Rinse all the acidic cleaner off the copper item, then either buff it until it shines or apply a coat of copper polish.