My guess is the spot (and it is very, very tiny) is from some airborne contaminant. Humans expel particulates through breathing, coughing, sneezing. Might be something else. Could have happened even in the grading room, which is another reason to avoid reholdering coins whenever possible. The bull's eye target developing around it might very well be growing. I snapped these photos when the coin arrived so I'll have something to compare its condition in a year or two. I'd be much more bummed if this were a tough date! Stlouiscoin, if I were you I'd take a shot and get it graded. NGC is a little more liberal with lofty grades for copper but then they generally sell for less. If the coin earns a 66 you're looking at breaking even. So it's a bit of a gamble but not much money is at stake. If yours has a nice full shoulder it is indicative of a nice strike. More desirable, for sure. Usually the O in ONE is also strong. These are opposite points on the coin. I'm sure you don't mean "wear". It's planchet roughness that did not get pressed out during the strike. Another common weak area is the AM in AMERICA, which corresponds to Lincoln's temple. The AM shows roughness more clearly. I'd be happy to submit it for grading, for you, if you don't have a better option. At either service. Lance.