Here's another example of MD. This time on the obverse of a 1919
Buffalo nickel. Doubling is again along the front of the face and, in this case, the date as well.
Full Obverse

Close-Up of face profile

Close-Up of the date

Once again, I didn't before realize that this coin had MD. Of course, it wasn't something I was looking for back in the day (over 35 years ago) when I bought these coins, but still...

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