Hey guys, I came across this and not sure what to make of it. Found a few close but not quite. Looks like maybe old tape glue but not really. Any help is appreciated and thanks.
To me, it looks like glue or some other adhesive. It looks like someone squeezed in ahead of me for trying some acetone.
I do hope everyone understands this means soak the coin. Sitting around soaking yourself in acetone overnight might be bad for your health.