Maybe some kind of crazy Lamination issue. David.. there is a Error Coins forum on CoinTalk.. create your Mint Error threads there next time.
Might it be a cud that took a hit and was knocked away (separated) from part of the rim where it had once been attached?
No.. CUDs do not attach themselves to the surface of a coin. A CUD is formed when there is a piece of metal that breaks off the Die and when it strikes the blank planchet the metal raises up and flows into the void of the Die.
It's definitely unique. I've got cud filled dates from around that year, this one just struck me odd. Makes sense since the center seems to have the same tone as the rim. I'll pay attention better next time to what forum I select..... <=== Newbie
On Lincoln cents? Wow! That's a pretty big cud, extending all the way from the rim to the date. Chris