1928B $1 Blue Seal Silver Certificate "Funnyback" Grades vf+. This lot is for a great example of the Funny Back $1 Blue Seal Silver Certificate. This note features the familiar portrait of George Washington that was used on all of our $1 bills through to today, and the back shows A large One Dollar and gives this note its name of a "Funny Back". This note does not have the familiar "In God We Trust" motto on the reverse, though, as that motto was not added until 1957.