While flipping out some bills to pay the rent this one caught my finger funny. Seems the ink has a very 3d feeling..like it is sunk in or maybe even raised. There is ink showing from the back. Anything or nothing special? Thanks
It's called "embossing" and doesn't really matter unless the bill is Uncirculated or in otherwise collectible condition.
I've never seen any of these in circulation but a few in some new straps of 5's. I don't think this qualifies as an error but is certainly unique. I've saved a few heavy strikes for the collection. It doesn't sound like they are worth a big premium but a collection isn't based on that. Not mine at least.
As coinsearcher pointed out this is called embossing. When the numbering heads are pressed into the paper, they leave an impression called embossing. This is desirable, since it indicates the note is original and has not been pressed flat to make folds appear lighter. It is not an error, unfortunately.
