I was going through some nickles and i found some different looking markings the first is a 1970 D first picture is normal second seems like a weak strike? and the third D looks square the second pic is a 1980 D the first D is clear, the second is filled in... why are these mint markings different?
Until around 1990 the mint marks were added by hand to each die. Because of this, some mintmarks are weaker, some were slanted and some were doubled. They also had to make new mint mark punches when the old ones wore out. Charlie
