http://www.new-guinea-tribal-art.com...weapons-maori/
I found this short reference that is good and covers a bit more than I have. you are right its PATU but I have no way of going back and correcting it.
ONE REFERENCE STATES THAT THE PATU WAS MADE OF STONE OR WHALE BONE BUT NEVER WOOD.THERE ARE MANY WOODEN ONES AROUND NOW SO PERHAPS THEY ARE OF MORE RECENT ORIGINS. SOME OTHER CLUBS WERE MADE OF WOOD BUT NOT STONE AS WELL. THIS INFORMATION MAY BE ABOUT THE OLD PRE-CONTACT TRADITIONS FOR MAKING WEAPONS. OF COURSE IN A ARCHELOGICAL DIG MOST WOODEN ITEMS WILL BE LONG GONE.