The black ink looks to be the same ink as used for printing. What does everyone think? Did it come from the BEP like this? Nothing on the back.
In your fourth photo, it appears to be part of a finger print. Either a BEP worker with ink on his/her fingers handled it, or it happened after it left the BEP. Without an analysis of the ink, you'll probably never know.
Looks like a Bureau of E Printing employee didn't wipe the plate correctly. From the pictures and depth looks like BEP ink. Minor printing error with hardly a premium. Time to read the books on printing errors. Happy hunting. Just got back from the Wyoming Valley Coin Club Show (PA). One collector went through a container of IHCents and cherrypicked an 1877 IHC in Good 6 (my subjective grading) condition. I spent 15 minutes with him and his grandson explaining the characteristics of the genuine 1877 IHC. Most dealers were trading in bullion and Silver dollars in bulk for investors. Did see a few ink smears like the posters and National Bank notes. Good small show.
Yea, I need to educate myself on paper money. I've been collecting coins since I was a kid, but haven't payed much attention to paper. After lurking in this forum for a while, I'm now checking every bill I get for serial numbers and errors.