1979-D LMC Woody & Unlisted RPM

Die flow lines and a damaged mint mark punch. (several dies show this on all denominations that year)

A damaged punch alters the shape of the mint mark. To identify if the punch is at fault or not, is to look at several dies from that year. When you see the same even happing over and over, then it is easy to identify the problem. If it is a RPM there will be just one die affected that way.
Here is an example:


The punch was damaged creating a false upper and lower mark on the inside of the west side of the upright.
While a RPM only affects the die is a pattern from an overlapping punch


Note how the top part is affected.
Here is a rotated RPM (punch turned slightly during the adding of the mint mark)
Note how it is altered. It follows the shape of a normal punching, but turned slightly.

Struck vertically out of alignment. (note the shape follows the punch)
Hope this helps.

1979 is one of those years its easy to tell something strange is happening. When I first started hunting I was finding about half of my 1979's had 'rpms' and that was just an astronomically high number when you usually find 1/100ish. This was the year that made me start collecting only listed varieties.