“Or an armorer’s tool for attaching a spear shaft and head?”
I could see it as a tool to make weapons.
But there would be wear around the holes.
The lack of wear on the object is really strange.
I think that the lack of wear is strange and probably significant.
This was not a cheap and easy thing to make, from what I’ve seen. It seems amazing to me that we do not know its purpose. It could be that the items we have found are largely unused. Worn and damaged items may have been melted down. The objects with identical hole-size may be ornamental.
It is certainly a mystery that I have never heard of.