I don't think I ever posted this Peace Dollar here. I know how this turned out but is there anyone here that would like to give a shot at determining what this coins slab label would read if sent in for grading?
Oh well, I guess I'll just show what it is. I wound up sending this to PCGS about 4 yrs ago. I have been contemplating cracking this and giving it an acetone bath, and resubmitting one day.
Interesting! I just expected "questionable color". Wonder what the residue is? I'd try acetone as well, or maybe xylene.
Acetone might change the color. I would try Methylene chloride or Chloroform. Use high-grade stuff or you will leave behind residues. Same with Acetone if you go that route - not the stuff you get at the Hardware store.
I've never used the other stuff you mentioned. I have used acetone in the past for tape residue, etc... and never messed with my color on any morgans I've used it on.
That color is incredibly unnatural-looking. I'd hope that removing the residue would change the color. Why would you think acetone would be more likely to change the color than a chlorinated solvent?
Acetone is more reactive and can oxidize some things that cause the color. The chlorinated solvents are inert - they won't even burn. Try some Acetone on a Q-tip and just touch an area not visible to see if it affects the color before dipping the whole coin. If the coin was brilliant, it wouldn't be a problem.
Here's a citation for methylene chloride attacking copper and nickel when water is present (which it usually is unless you take special precautions): That's more reactive than acetone, which has only been shown to attack copper in the presence of water and intense light -- copper is claimed to catalyze the reaction of acetone with water to make acetic acid. (I have doubts about this claim, because copper's well-known to catalyze the oxidation of acetone to acetaldehyde at high temperature in the presence of air; photocatalytically oxidizing acetone to acetic acid seems a lot more plausible than metathesis from acetone and water to acetic acid and methane.) Getting acetone to act as an oxidizer? Good luck, unless you're pouring it onto alkali metals...? If acetone changes the color of a piece like this, it just means that there was a layer of something organic causing the color ("residue"). Sure, if you want to keep this unnatural, un-market-acceptable, and un-gradeable color, you should keep acetone away from it -- but because it will dissolve the colored goop, not somehow oxidize or bleach it.
Some sections of that P$ look NT others not so much. I would acetone it as well and see what happens.