Rest of the set are immaculate, obverse is absolutely perfect. Will removing from the cello and spot treating with acetone do anything for it?
Looks like corrosion from a pinhole. Because of the flat angle, I can't see the depth, but acetone doesn't touch this. Dip or leave the same as I see it. Sorry. Jim
Welcome to CT. Coin dip would remove most of the black but I'll bet the surface is already damaged under the spot.
spot treating it with a coin dip would definitely help (not the entire coin, just the spot). But as mentioned, the surface is probably already degraded and damaged from it.
Thanks for the replies, probably break up the set and find other uses for the proofs less the Franklin of course. Thanks again.
