A kitchen knife, a tool weapon ... or what ?

[fernando]

The offset tang and the bolsters suggest this this an old kitchen knife.
However the thick square cross section of the said tang, the absence of grip rivets and the shape of the blade back, could suggest something else.
Also the size is rather large, though not impossible, for a kitchen knife.
Blade 26 cms. (10,2") total length 40 cms (15,8").
Any suggestions?

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