Pictures aren't great (it usually helps if they are straight on instead of at an angle), but I think what you are seeing is the result of die fatigue. Keep up the hunt!
It's a form of die deterioration that's called a "ridge ring." It's common on copper plated zinc cents.
What you have is a coin planchet that was cupped when punched out and when coined this is the result. If it had been on the reverse side, you would have had the same result to the reverse.
