Well this was a bloody challenge! Got there in the end though.
This is a 6th/7th Century Angon, and is a dimensional copy of one in the British Museum.
The entire Angon is forged from phosphoric iron, and the barbed head is a separate piece forge-welded on. It's 1 meter long and octagonal in cross section the entire length - not easy to forge!
The socket has a forge-welded iron ring that is hammered down once the wooden shaft is fitted, to compress the socket ensuring a solid fit.