Its not a stain, it's not my imagination either.HA,HA! I need a better camera so I can get better definition. Please someone tell me I'm not going crazy!:rolling:
I think I see what your looking at, not a repunched mint mark but a shadow "D" under the prominent "D". You might use your paint program to circle what your talking about, just to be clear. I have my doubts if it's really an xtra mint mark, often times metal flow lines and imperfections of coins surface makes it look like letters. If you look below the shadow D in your first picture you can also see what looks like a shadow "F", I have a 1942 non war nickel that has what kind a looks like a shadow "S" where mint mark is on non-war nickels, I think it's like your coin (metal flow lines or die scratches resembling letters). But I could well be wrong, I note there is a variety of 1956-D cent that has a shadow "D" below orignial mint mark and is listed in most value guides. Thanks for posting your find, interesting coin, curious what other's will think of it.
It looks too small to be a repunch, which should be the same size. here is a photo of my 1956 d/d RPM 8 which is the shadow mark mentioned. Jim
http://www.lincolncentresource.net/forums/attachment.php?attachmentid=9108&d=1239022324 --check this out . someone putit closer for me.
There is some small chance that this could be a secondary D, but I would have to view it under a microscope to tell for sure.
