[left]I come across this Lincoln cent and searched Error-Ref for something close. Could this be a Reciprocally Deformed Convexo-Concavo Die? Here on the obverse and reverse are gas bubbles (I'm guessing) on the fields and devices and the rims are pitted.
Here is a side view of the obverse from north (white arrow) to the south. Blue arrow (Liberty) and red arrow(Date). Convex side.
Here is the concave side looking from south (white arrow) to north. North rim (red arrow) and the top of the Memorial bays (blue arrow).This is what I came up with. Am I anywhere close? All replies are welcome. I don't see any hits on the obverse or reverse.