I have a 2006 US nickel, the one with the new Jefferson face, and the old Monticello on the back. It looks like there was a mistake stamping Monticello. There is a semi circle above Monticello--kind of gives it a halo affect. Anyone else seen this?
And, where is your signature? Huh? Huh? After all that we went thru for you, this is the gratitude that we get?
If it's not actually a mark, but more of a light reflection when the coin is turned, it is due to a weak strike.
Perhaps he is referring to the effect from a clashed die? It would be easier if you could show a picture.
Frank look at my signature next to semper fi it will always be there. and here. Bruce the" Frank group"
It is possible that you may have found an error but what you may have is a coin that was on the end of a roll of Nickels and which received damaged by the Bank Wrapped Rolling machine that closes the ends of the rolls. If you can provide pictures, then we could make a more informed assessment! Frank