Seller describes environmental damage as - "AMAZING GREEN PATINA" Yours today for the very reasonable price of 19.99 +5 shipping
My uncle made us dollar rings when we were kids. I watched and watched him but could never duplicate how he did it. Fond memory, thanks for sharing.
I have since forgotten how to do it, but a few years ago I taught myself the technique with the help of the Internet. If you're an uncle or a grandparent, etc., it's a good skill to have! Nice for tipping, too, if you use denominations bigger than one dollar.
If you are judging a copper roof, then the "green patina" is what people look for. Maybe this seller is a roofer?