This is Noland's bone axe. He has this in hand as he is obliterated by the Tracker Predator's cannon, clearly shown in this publicity shot and even made as an accessory with the Hot Toys figure.
The large jawbone area with teeth is resin with a metal blade set in, there are ornate connections looking like futuristic plumbing pieces, these handle details are resin with metallic cord and leather lacing wrapped around.
