Just wondering if this is zinc rot or possibly an rpm? Couldn’t find anything like this one. Thanks for any info!
Not an RPM just an average zilincon anomaly I don't even bother looking for them besides 1982 and under but still a cent http://www.varietyvista.com/02b LC RPMs Vol 2/RPMs 1988D.htm
Split plating along the edge of the mint mark exposed the zinc core and led to corrosion. Split plating in this area was a problem on early Zincoln cents in the 80s.
These mess up there a lot. The strike dislodges the plating, then nasty things pop up in the void, like that white junk. While it looks like a part of a D, that's the orientation of the lifted plating, not another mint mark.