Some form of ejection related ( PMD) perhaps?
This and the 1970-D have obviously been circulated heavily, but finding the similar flaking on the MS 1968-S with bits of the inner rim appearing to be stuck in the field has me revisiting these examples (I filed them away about a year & 1/2 ago).
This and the 1970-D have obviously been circulated heavily, but finding the similar flaking on the MS 1968-S with bits of the inner rim appearing to be stuck in the field has me revisiting these examples (I filed them away about a year & 1/2 ago).



























