This is a 1962 proof in the cellophane pack. I'm assuming the red spot is the early stages of silver toning but I've never seen a spot develop in the middle of a coin before (but I don't examine zillions of coins either) The cellophane appears intact. Any suggestions on preservation or should I just leave it alone? I'm thinking of transplanting the set into a capital holder.
I'd suspect one of 2 things: Either, there is a small hole in the plastic that has allowed air and gasses to enter, or, there was some contamination on the coin when it was put in the plastic. If you do transplant it, I'd recommend an acetone bath. That will remove any contaminants and should stabilize the surfaces.
You made me think about original toning and the acetone, If a coin that is reacting with some sort of contaminant or stored condition. Will an acetone treatment completely stop the toning process, or will it just delay it's progression if left in the same conditions?
Looks like toning to me. Look closely and you can see multiple colors on the torch and the handle of the torch. Also more coloring in the area and letters near the torch. The back ground also looks as if it's starting to turn color. I would leave as is. If you remove it then you loose the original government packaging. Not sure what the date is as you only posted the reverse. If you don't want toning buy another proof set for that year.
I have a proof set sealed inside hard plastic for 30 years and the quarter is toning. So I am sure a dime could tone in a cellophane pack.
If there is a contaminant on the surface, acetone will probably help. For example, if someone touched the coin before it went into the set, acetone will help. If someone sneezed in the presence of the coin, acetone will help. If there is a random pinhole in the plastic and air has been interacting with the coin in an otherwise sterile environment, acetone won't help. In short..... acetone can't hurt the coin, but I can't guarantee it'll help it either.
Very, interesting I had the thought that acetone might end the toning and aging process. It must create an inhibition to the otherwise original process.
Thanks for all the replies. I had decided upon an acetone bath and a transplant into a Capital holder when I came upon the vintage holder below (a Capital Jet-10) - for cheap! It allows you to encase the set without removing it from the cello-wrap. So maybe I slowed down any leaks in the cellophane while satisfying my OCD need to leave it in the OGP. Win-win! (don't argue, even if you think it's stupid - which it may be ) The set's a 1962 and I've owned it for about 30 of the 56 years it's been in existence, so at this rate I'll likely be gone before the toning gets too bad (or good) anyway.
Acetone has no effect on toning itself, none. It neither increases nor decreases toning, nor will it remove toning. But what it can do is remove some foreign contaminants, and I say some because it won't remove all of them, from the coin. And sometimes foreign contaminants can induce or even exacerbate toning. So if those foreign contaminants are removed from the coin, that's how and why acetone can be beneficial.
