The missing copper coins should be silver in color, at least when they are struck. When the copper has been chemically removed it can discolor the zinc core turning it dark. Also it's better to research the coins that have sold to get a true value, not the asking price.
Please post photos of the coin. It's impossible to give opinions on a specific coin without them.
ANA ID: 3203813 - CONECA ID: N-5637 Clean a coin that may be worth collecting? Please DON'T! When in doubt, leave it dirty!!























