Got some spare deer or elk bones laying around? Historically, deer and elk bones are great for crafting tools, such as this primitive-looking bone knife. The blade itself comes from an elk leg bone, cut and ground to a fairly sharp edge, while the handle is deer antler wrapped with elk sinew, pine pitch, charcoal, and processed plant fiber. It may not be the most efficient of knives, but if you have a few tools and want to make some use out of those bones you have lying around, this is one method.
Just be aware that bone is a relatively delicate material, so bone knives are typically used for slicing fish and game. You will not want to do anything rough—like batonning—on a bone blade.