This knife was used by Vin Diesel during the the filming of The Chronicles of Riddick. It's a very decorative design and is made of a dense rubber to protect the actors during filming and was used by Riddick on board the Necromonger ship to send a few Necromongers to the Underverse!
Although only seen for a short time, the knife can be screen matched to the one that Riddick pulls from his stolen Necromonger armor thanks to a chip in the paint on the handle, a mark on the blade and two casting imperfections on the 'horns' of the handle seen in the screen capture.