It certainly is very old ... but what is it ?

[fernando]

Total length 36 cms. (14").
Pattern of marks on both sides has a similar tendence, although more extended on the front. On the back, near the socket, there is small symbol ... maker's mark ?
As so often with these things, it can be seen by the beaten socket bottom, that it was some time used as a "modern utensile", like a chisel.
It was gathered in the Country interior, in a tiny country village with a very old monastery and a medieval tower, this now used for residential tourism. This doesn't mean this piece once belonged there, but it has all the looks of being a very old item ... in my ignorance, i would dare 17th century ??? .
One thing that intrigues me, not being a connoisseur, is the edges of the blade, that are completely "squared".
Although the socket and the general shape of this piece makes me think this is a weapon, i wouldn't be sure without a help from someone who being more within this area, or has ever seen something similar.
Gentlemen, i will apreciate your coments.
Fernando