Spots/stains clean or not clean? Silver Washington

clackamas

Probably a stupid question but I mainly collect copper. I have a Washington quarter (Silver 1976-S), still in the mint plastic. It has some spots of what looks like PVC. It can't be PVC and is probably toning that has turned green. The spots are visible to the unaided eye but not too bad. My question is: will they hurt the grade when slabbed? Should I cut the coins out and dip them in acetone or silver dip? My instinct is to leave them alone since its a perfect coin without a nick on it and will grade technically high. With copper this is a grade limiting thing but on silver?

cypher

Can you provide a picture by chance for compairison? I've got some also doing the same just sittin around, I've just left them sit however as it isn't bothering me too much.

Mikey

Isn't pvc generally a film over the whole coin, or a localized spot?

clackamas

Legit PVC can be spotty or an entire film. I have had coins bagged for drops of PVC. I have seen old plastic with litterally drops of pvc in places. This is not PVC but it looks like it.

richbeat

The silver bicentennial quarters have an outer layer of 80% silver and 20% copper, with an inner core of 20.9% silver and 79.1% copper. The green is a chemical reaction to the copper. I'd get it out of the mint plastic in an effort to stop the process if you're really concerned about it. I've read several threads about what to do to stop it, but unfortunately I don't remember the details and I wouldn't want to give you bad advice. You can use the search feature and possibly pull up some or all of those threads, or maybe by bringing this back to the top a good knowledgeable person will chime in. Good luck!