You may be seeing the area on the design that's behind the columns. The opening to the Lincoln Memorial and the columns that run down each side are part of the original "Memorial Reverse" design.
This image shows the area in question and give an idea of what the engraver, Frank Gasparro, intended the coin to look like.

ANA ID: 3203813 - CONECA ID: N-5637 Clean a coin that may be worth collecting? Please DON'T! When in doubt, leave it dirty!!





























