By far, this is the most heavily imitated of all "state seals" on railroad stocks and bonds. The most common vignettes you will see on Pennsylvania certificates resembles the above design which is the official coat of arms of the State of Pennsylvania. While both horses are black in the official version, a majority of the unofficial imitations use one white and one black horse.

In truth, the official state seal is merely the central shield framed by an olive branch and a stalk of maize (bottom design.) On the shield is a ship, a plow, and three sheaves of wheat. An eagle perches above.