How to clean Copper
Materials needed: One small container (glass or plastic) with a matching lid; White Vinegar; Dish Soap
Place the piece to be cleaned in the bottom of the container and cover with White Vinegar. Add a couple of drops of Dish Soap.
Put the lid on the container and shake for at least 10 seconds. Check the piece; it may need to be in the solution for a bit longer (just check it).
Remove the piece and rinse with clear water. The White Vinegar and Dish Soap solution can be saved and reused again.