Trussell is a term often seen used in relation to hammered coinage or coins made by hand.  Hammered coins were made by placing a flan (blank piece of metal) between two dies and striking the upper die with a hammer to get the desired image on either sides of the coin. Trussell is the upper (of the pair) hammer-striking coin die. The bottom die is called anvil die. Trussell is also called hammer die.