Saw / Knife makers Anvil

Here is a Unmarked block of steal with a handle built in. It weighs 55 pounds -/+ ( bathroom scale ) 6 inches wide 10 long and 3 1/2 inches tall
This is a nice size for forming metal, or using for a backer for rivets.
There are dings and surface rust on it, could not find a makers mark, could be a saw makers anvil or a 55 pound counter weight? I used it for a anvil