Look at the edge. From the pic, it looks possible that you might have a partial collar broadstrike. If this is the case, the edge would be missing the reeds for part of the coin.
If the edge is intact, then I would guess that this coin was struck a little hard and the rim was squeezed upwards a little to give the rim the appearance of having more metal. I've seen alot of dimes like that while roll searching. I don't know the cause for sure, but it does catch your eye at first.
If the edge is intact, then I would guess that this coin was struck a little hard and the rim was squeezed upwards a little to give the rim the appearance of having more metal. I've seen alot of dimes like that while roll searching. I don't know the cause for sure, but it does catch your eye at first.




















