I certainly don’t recall ever before seeing such a 100+ year old cent in change like this one. I have half a tube or more of 1918 circulation find cents and none are even close to this one. Must have been hanging out in a piggy bank for most of its life. Odd coloring on the obv, but nice details on both sides.
Very nice. The color may reflect a brassier mix in the alloy. With the end of the one cent in commerce, somebody may have dumped a long-held penny jar.
I did give it an acetone bath for about an hour at most just to see if any of that would melt away. It did not, it does not seem to be anything on the surface. So maybe it is an alloy matter or maybe just some kind of staining.