I have used acetone, but it comes with problems. As you know it immediately begins to evaporate when it is poured into the container you are working with. A small tight sealing jar is recommended. If you don't contain the fumes, they can be overwhelming. Lots of ventilation is required. Nail polish remover is a cheap source of acetone, even with lemon or lubricants. You would want to wash your coin gently afterwards anyway with mild soap and water. If you are not sure of what the material is that is stuck on your coin, 91% isopropyl alcohol is good for some stubborn dirt and grease, and it dries fast. If you have some partial containers of paint thinner or mineral spirits, you might try that. I would guess actual paint remover can be purchased in smaller quantities now. When I used it to restore antique furniture, it was a dangerous material and came in gallon and larger cans. There are safer products now, but probably not worth the expense for just one coin. You can soak silver coins for up to a few hours, but copper, bronze, and base metal coins react poorly to acetone as it strips original surfaces and leaves the ugly raw finish of a cleaned coin. As you know don't rub your project coin. Simply blot with a soft cloth or tissue. You can use Q-Tips, but believe it or not, cotton is abrasive. I found out the hard way. You can still use the swabs, but ever so gently. I don't recommend "tumbling" or any harsh rubbing. If the foreign matter doesn't come off with solvents, you may have to resort to a "coin dip" product that you can purchase on-line for about $8.00. Go slowly, and I hope you get good results. Be safe and Good Luck! Phil
