Son brought a 7lb sledge hammer in sore need of a new handle, broken off at the head. He wanted to break up some rubble before concreting.
The hammer was thick with rust and showed every sign of abuse along life's path. The casting has a series of dents all across the surface with the hole for the handle. The hammer's faces have no significant marks.
The dents look like they have been made with a big cold chisel or perhaps a mattock.
The origin of the hammer is obscure, and I can see no reason to make so many dings so completely aligned at about 45 degrees to the axis of the hammer.
My guess is that perhaps someone was trying to knock the head on or off, but hitting one hammer with another in my book is a silly idea with the risk of high speed steel chips causing some GBH.