The images below are of a 1969S Proof I found in the recent box of halves I searched (see the Roll Searchers thread). There are many green spots on the front that I think are rather unappealing. Is there any cleaning that you can recommend (I know that cleaning is almost always not recommended), or should I just leave it alone and be glad that I even found a silver proof? The areas circled in red show where the worst of the green is (although the pictures wash it out a bit - it looks greener in person).
Look at it this way. You could go to Walmart, Kmart, Target, etc and purchase some Acetone for about $5. Then if that doesn't work, you could purchase some denatured Alcohol for about $4. And don't forget the distilled water for about $1 or more to rinse that coin after the above. Then throw in your gas money to run to those stores and you now have several more dollars. So for a coin worth about $2 to $4 you end up spending about $10 to $15 and still end up with a damaged proof that still is worth about $2 to $4 or even less since it is a damaged proof. A long story to basically say the same thing already noted by bhp3rd.
Is that PVC residue or something else? Pictures are a bit small and hard to tell what the damage is. My opinion, since the coin is worth so little, you can use it as an experiment piece for cleaning techniques and see what works and what doesn't. I'm nowhere near experienced enough to give you any actual technical cleaning advice though. But I'd try it just to learn! Chalk up the loss of a few bucks to a learning curve.
I think it is likely PVC. If you click on the pictures you should be able to see a larger version, I think the pics I posted were around 600x600
Although I agree with the comments below, I would also like to agree with Sasha. Spend the money on acetone, gas, distilled water, and whatever else and experiment on it. A great learning experiment.
Fortunately, no gas cost as I live in NYC I think I have some acetone lying around somewhere, so I'll give it a shot. How critical is the distilled water?
I'm in the NYC suburbs so gas cost in my #1 concern lol! Don't use the nail polish remover acetone, it's not pure and has other stuff in it that's harmful to coins. Distilled water, funny enough, is the simplest and one of the best tools. I find that it lifts more grime, dirt and all the other stuff off coins better then chemicals and it does ZERO damage!
It washes the chemicals off, and because it's distilled, it won't react with anything. Plain tap water (NYC water) could contain reactive chemicals.....
