Hello everyone! I have been playing with a new light box and noticed a few green spots on one of my silver Hellers. Any opinions on if this is PVC damage or a stable deposit? I store all my coins in saflips, but these arrived in some older plastic flips. I have not attempted to clean before, just wondering your opinions before I break out the acetone. Thanks in advance!
I see the problem. If it is PVC damage, try soaking the coin in a 100% acetone bath. The acetone will not damage the coin, and it will dissolve any PVC gunk on the coin. If the PVC spots are hard, you might need to let the coin soak for several minutes, until they disappear. Then, rise the coin with some distilled water. If the green spots are due to oxidation of the copper used in the alloy, the acetone will not remove them. But, judging from what you said about the earlier storage of the heller, I imagine you have some PVC deposits that need removal. Make sure you use 100% acetone and not nail polish remover, which is a lower concentration and often perfumed with some cloying scent. Also, remember that 100% acetone is extremely flammable and avoid the fumes - use it in an open space and way from any flames or source of ignition. If, upon re-examination, some spots are still present, you will need to repeat the process. Some old PVC deposits can be stubborn, but with persistence you should be able to remove them.
Thanks for confirming my suspicions. I really appreciate the help. Ill break out the acetone and report on the progress.
Looks like copper deposits, notice the roughness under the deposits which is indicative. But soaking in acetone will not hurt the coin. pvc deposits are usually more superficial and less demarcated: After a brief soaking in acetone
In my own opinion , I think it does looks like pvc damage , you could try to soak in 100% acetone as @robinjojo says , but you have to prepare for the color might be slightly change , usually not because of metal issue , most of this cause is because the soil has been washed , so it might be appears different looking before it washed. Here is my example of Henry vi groat. before washed /and washed.
