"I’m stumped. Solid metal. Afaik everything you see is the whole thing. Knuckle is an inch. The copper bar rotates about the screw head a few degrees."
A: "A very obscure tool used by modern flintknappers for “indirect percussion”. The rounded parts are for the legs and the copper bit is placed against a knappable stone and whacked to chip the stone. A.K.A rocker punch."