The pawn shop guy looked at my 2am coin haul and told me to stop cleaning them
I was about to scrub a handful of old mercury dimes with baking soda paste when the guy behind the counter in Cicero told me that cleaning them knocks off half the value and just leaves tiny scratches. He pulled out a jeweler's loupe and showed me the hairlines I would have put there, then said "let the grime be." Now I just soak them in room temp water and a drop of dish soap, so has anyone figured out a way to get the green gunk off without touching the surface?