Looks to me normal contact marks from circulation. Then the coin gained a patina. Then someone cleaned it and the deeper marks retained the oxidation.
The blob of metal near the M can be from a hole in the die. Corrosion but on the die. Photos are not sharp enough to be certain. Which mint?
The blob of metal near the M can be from a hole in the die. Corrosion but on the die. Photos are not sharp enough to be certain. Which mint?



















