OK. It clearly has some age to it, but whether it's Iron Age or substantially later is a question that probably only a metallurgist or a museum expert could answer.
Just one other thing. There is a suggesting of a rectangular depression but it doesn't look to be a hole that goes all the way through. If it did then that would be a hafting hole. Is is just blocked with rust or a mixture of rusk and decomposed wood; or just a coincidental part of its general deterioration that happens to be be that shape.