Little Background info on coin: this coin along with everything else has been kept away in a box for almost 25 years (1991 to 2016) in a sandwich bag. I assume that if acid has touched it, that I would see corrosion somewhere on the quarter, but there are none which I find strange considering that this quarter seems to not be made out of silver. I also, see some small black prints/stamping of either letters or numbers. The quarter's side where the lines are, seem to not have been touched by acid at all. I'm just confused that if acid had been used, why is there no corrosion? Can someone explain this to me?
I guess it depends on what definition of corrosion you use because I see corrosion all over that coin . Looks like a dug coin to me , but I wouldn't rule out acid either .
It looks like to me that that quarter is not silver cause it appears to date 1982 so who knows it could have been in a sink drain and drain cleaner could have done that.
Coke and Pepsi would not do that to a coin regardless of how long the bath occurred. Try it yourself.
I think we are seeing the results of electrolysis. It's very common in cases where dissimilar metals are in contact, or connected, as in salt water. The ions in one metal will migrate to the other metal.
