large old bridge builder or blacksmith anvil rivet header tool

Heavy old blacksmith's tool for making a domed head on rivets. It is a heavy hexagonal bar with a domed depression in the one end. It measures 4 3/4" long and 1 1/8" across the flats. The bowl is 3/4" across and 1/4" deep.

This old tool has a patina of age and one end is rough.