I dug this copper as part of a three coin pocket spill back in 2015 while metal detecting. It appears to be hammered, as do the other three coins. It was found in a 1600's MA town, so they could potentially be very old. They are heavily corroded, and only one has legible detail, what looks to be a large crown. I will be very amazed if anyone is able to ID this coin, good luck!
Ahhh..... no I cant really identify it. But it is probably a old large cent, do you have a picture of the other side?
I don't have a scale to weight it, but the diameter is 20mm, around the same size as another coin in the spill. I was thinking that it may be a Scottish Charles II hammered copper, but the crown on mine seems a bit different (from the limited detail I can see). The diameter is the roughly the same though.
I outlined what I am able to see most clearly. There also appears to be writing on the edge when viewing in hand, but it is so worn and corroded it isn't legible.