Could this qualify as the oldest knife in the world?
Since this knife topic has my curiousity of the Boker switchblade values, instead I found this sellers posting on ebay.
BOKER TREE BRAND Petrified 125 to 160 million year old Dinosaur Bone Lock Blade Pocket Knife. Damn pricey but a neat piece. I suppose one could get a piece of petrified wood for much less and grind - lapidary work as a handle.
BOKER TREE BRAND Petrified Dinosaur Bone Lock Blade Pocket Knife Knives | eBay