I am interested in learning what is allowed in the way of cleaning. Please clue me in. Is a soft jewelers cloth allowed?
No. Unless you know exactly what you are doing, the most I'd do is soak the coin in 100% acetone (available at hardware stores/Dollar General/etc.)
No, using a jeweler's cloth would be polishing, and polishing is a form of harsh cleaning. There are ways of cleaning that won't hurt numismatic value, but all forms of harsh cleaning will. So, if you have coins worth more than face/melt value that you believe should be cleaned, post picures of them here on CT and we will tell if and how it should be cleaned.
As a general rule there 4 acceptable ways, methods of properly cleaning coins. 1 - distilled water 2 - acetone 3 - xylene 4 - coin dip All of them involve rinsing, soaking, or dipping the coin anywhere from 1 second to several days - depending upon which method you are using. And no mechanical action of any kind is used on the coin with any of them. Now you could add pure alcohol, or as close to pure as you can get (92%), in there but in almost all cases 1 of the 4 above will do the same things it will.
