Repunch mint mark? or Zinc Rot? or maybe even both? ... there are no other places on the coin showing the same signs of zinc rot, if that's what it is.
Nope. Copper plate was broken during striking. The elements got to the zinc. That's zinc rot. Very common on zincolns.
Is that why the rot is surrounded by a raised surface? The mint mark itself bears a remarkable resemblance to zinc rot. Is there a way to tell the difference? or maybe it doesn't matter. If there was an RPM there, it's not really there anymore.
No to RPM.. Just the plating issue as stated. Look at the first part of this webpage http://www.error-ref.com/?s=Zinc+rot
