Giant ball pein sledgehammer... roughly 8lb. Any idea what on earth it's for?

As per the title, 8lb sledge with a ball pein on one end. Any ideas what it is for? Seems too big to be useful for smithing but idk. Cleaned it up and put it on full length sledge handle, but no idea if that's what it was on originally. Found in the UK (Wales) if that helps.