I stopped in my local coin shop and ended up in a discussion with him about cleaning coins. He said that Acetone works well but that you (me) could end up ruining a coin. "It's best left to the professionals who know what they're doing and that he has done it a couple time to "freshen" up a coin." Then he made reference to a coin that I had just bought from him (either a silver round or a silver eagle) that I had just bought. I couldn't figure out which.
Seeing that I had just purchased some coins from him, the above quote really didn't sit to well with me. As I was thinking about all the other coins that I had purchased from him. So I think that I'm behind the

.
On another forum they call it giving a coin a bath.