Is this true doubling or mechanical once again? This only appears on the UNI of United on the Washington Dollar.
It looks more like a re-cut Die to me! Possibly a design change to correct an error either in the design or to correct problems with premature Die failure. Frank
Looks like neither, it may be grease or some foreign object on the die. Definitely not mechanical or a real DD.
I agree, it looks like some material was stuck in the recesses of the die, causing recesses in the coin.