Are bones of animals used to make swords?

Are they? Not really. In the current day and age, it’s generally easier to head to a dollar store and buy a cheap kitchen knife.
Were they? Again, not really. Primitive peoples did make small knives and such out of bone, but a full-length sword made of bone would not only be flimsy, but it would also lose out to flint in terms of durability, sharpness, and style. In addendum, spears were usually the way to go in the stone age – nobody had really figured out how to make a true blade yet, and the few who did probably found out that swords were shorter, flimsier, more expensive, and less effective than a sharp stone on a long stick.
This doesn’t mean that bone weapons weren’t used, though. If you’re a prehistoric man and you stumble across a saber-tooth tiger carcass, you may find that the femur looks an awful lot like a club already. In fact, if you make that bone into a club, you can kill another animal and make at least two more clubs from its bones!

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