I found this $1 dollar coin of george washington with a extra letter O on his face.http://s1232.photobucket.com/albums/ff378/loulou1066/?action=view¤t=IMG_1650.jpg http://s1232.photobucket.com/albums/ff378/loulou1066/?action=view¤t=IMG_1647.jpg http://s1232.photobucket.com/albums/ff378/loulou1066/?action=view¤t=IMG_1646.jpg http://s1232.photobucket.com/albums/ff378/loulou1066/?action=view¤t=IMG_1589.jpg
All I see is what looks like a damage point from contact with another coin or something hard enough to make the spot, but I'm 99% sure that it happened after the coin was minted. It is what's called PMD or post mint damage. I may be wrong, but I don't think it's an "extra O" in this case. Let's see if anyone else thinks different, as I have been wrong before. Sorry, Ben Jenkins
If it was a mark on the die, it would be raised. Looks indented and thus is coin damage from contact after it was struck.