I have a few of these 1952-D Lincoln Cents, and on the original 2x2 mylar it mentions a "D" near the rim.

1952-d Lincoln Cent with d near rim.JPG

It took me a little while to locate a reference for this coin. Its one of the few Lincoln Cents I have that is way out of the typical mint mark placement area.

I love the RPMs and OMM errors that are dramatic. The RPM's are pretty much dwindling down on the availability of RPM's.
I have thousands of BU RPM's that range from 1944-D to 1972-D.
Eventually these will increase in value, since they have not been produced since the mid 1990's or so.