Welcome to Coin Talk. IMO it looks like part of the coin was exposed to the elements and part was covered by a piece of paper, cloth or something else (?).
I'm with Thomas. I wouldn't even call that toning. Looks more like environmental damage. Do you see that sharp curved line? You would never see that with natural toning. You might see that with artificial toning, but really, only if the nimrod doing the fake toning didn't know what he was doing. Remember as a kid in school when you took two pages of colored construction paper, cut out a design on one, and laid the design in the center of the other page, then put the whole thing in the window under the sun for a few hours, and when you took the top piece off, you had the outline of the design? That is what Thomas is talking about. Something caused that line, but it wasn't natural toning. If that coin has been sitting somewhere with something else partially across it, for many years, undisturbed, then it could be natural toning. Time tones naturally, Man does not.
Your coin looks to have natural toning. It may of had another coin on top of it and in storage for a long time which can cause the curved line. I have seen countless coin with the same effect. All toning is environmental damage. But if it is a pretty color people call it Toning, if it is a drab color people call it Environmental Damage. All toning is man made. Some by accident (natural) and some on purpose (artificial).
Are you telling me that all toning on the coins that @paddyman98 finds while metal detecting is man-made? From the sand and salt air on the beach? From the dirt in the park? Did a human put the coins there intentionally, expecting to return one day like a squirrel to dig up their "nut"? Chris
