PVC Contamination? Pics Added

scmoore61- PVC contamination is a form of damage that is caused by coins being stored in PVC plastic holders. These holders were frequently used in past decades and are still used today, but most collectors know better than the use them (though they are much more commonly used in Europe). Over time as the temperature and humidity of the air around the holder changes, the the coin within the PVC is contaminated by a sort of green grime that leaches out of the plastic. The PVC contamination would appear as green or even dark blobs on the surface of the coin. In the case of your coins, it may have already been removed, but slight traces of the PVC may still remain. The only way to remove the PVC damage/ blobs is through cleaning with acetone (in more mild cases) or with a harsh chemical cleaner. Either way, it is impossible to cure the coin of contamination without cleaning with chemicals.

Remember that even a TPG service could be mistaken. If you've looked at those coins with a decent magnification and could not detect any spots, corrosion, greenish discolorations, the possibilities of the place you sent them making an error is possible. If you've soaked them in Acetone, rinsed with distilled water, blow dryed and still can not see anything, I would resend them for grading a second time. However, only if you think the cost of continuosly grading attempts is worth the price.

I still suspect that the grading service just assumed that this coin has had PVC or something similar on it at one time. Due to the condition of the coin though, that is difficult to determine. If you can not see what they are talking about and your photos show no signs of such corrosion or PVC, I still would suspect they just made an error.