Found this in change today. I've seen other coins posted similar to this stating an error in the annealing process can cause the copper color. Is it possible that's what's going on with this quarter or something else? Thanks in advance for any input.
environmental damage. Or just plan damage. the copper color can easily be made on coins. Put a copper penny in some Muriatic acid along with dimes, quarters etc and you will get this EXACT result. here's an example (scroll down to the bottom half of the post) : https://www.cointalk.com/threads/post-your-pmd-post-mint-damage-coin.318993/page-2#post-3132617 although I have some quarters like this too but no pictures handy. It also could be a tea stain for all I know - might need some pictures up close more, and some more expert opinion. @paddyman98 @furryfrog02
