A heavy spear (lance) head ... or what?

[fernando]

Some kind of polearm head, like a partizan or the like?
I guess gate iron rails (this the name?) are not so (sort of) sharp like in this case.
Neither would they be so large; this blade measures 45 cms (17 3/4").
On the other hand, the socket denounces to be a later work ... both "pipe" and rim.
What would this be?

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