I have some silverware that was found in a saltwater environment. It has some encrustations on it, and I need it cleaned to see the silversmith marks to help identify it. How can I clean it and not damage or pit the silver? I spoke with a coin collector who cleans old coins, and he was of little or no help. I'll get some pics up in the next day or so. I can't damage this stuff because it may have some historical value. I would have it done professionally if I knew who to send it to. Thanks.