I think its a struck through delamination.
The curved mark looks to match the shape of a cent. I think a major lamination on another cent planchet completely peeled off before striking and ended up getting struck into this coin.
The horizontal line that goes through it is probably part of the same lamination but this piece wasn't completely separated from the rest, so it rotated before being struck.
That's my best guess.
The curved mark looks to match the shape of a cent. I think a major lamination on another cent planchet completely peeled off before striking and ended up getting struck into this coin.
The horizontal line that goes through it is probably part of the same lamination but this piece wasn't completely separated from the rest, so it rotated before being struck.
That's my best guess.

























