I've been sitting on this one awhile and decided to post it because I have not been able to locate one listed like this one. So maybe someone here may shed some light on it for me. Obviously we are looking at the MM . But also is there some notches on the 9 in the date or am I just wanting to see them. One more issue is at the rim SE of date the two spots are in relief. See last pic. Lol
From opening some BU rolls of 1960 D cents, I have noticed that is just how the date is designed. The notching, if that, isn't anything significant. The RPM you are showing though looks to be the 1960D-1MM-005 on CopperCoins or WRPM-010 from Wexler's, but I cannot see the die markers clear enough to know for sure. I am just going off of what the RPM looks like compared to the listed ones from those two sites.
There are 113 varieties for this date. Check against this for the die markers for the stage http://varietyvista.com/02b LC RPMs Vol 2/1960DRPM005.htm
You should check out this site and surf through the 113 RPM's listed. Through the first 60 variations, I spy 5 which may apply: 005, 027, 029,037 and 048. Check the rest of the varieties. http://varietyvista.com/02b LC RPMs Vol 2/RPMs 1960D (1-60).htm