Okay it is not a weapon. These are food knives rich in social symbolism. From the most isolated islands. Not including myself, I am guessing there are at least three other members that may be wowed by this. Got it today in a charity shop for less than two pints, labeled as a page turner. I have added a snippet of supporting information from University of Hawaii Press "Arts of Vanuatu" There are four pages about the function of these knives, I would be happy to upload if any interest.
The spaces between the spiky looking bits on the handle indicate the status of the owner. They symbolise the ovens or hearths the individual is entitled to eat and sit at in the men's house.
I will stat a new page for more stuff.