People made edged utensils long before they understood metallurgy or knew how to work metal to produce actual blades. Some primitive people still make edged utensils out of bone, wood, etc.
The most interesting thing I read about all this is ‘Book of the Sword’ by Richard Francis Burton.
Here is an obsidian blade. Looks very deadly............
Burton's book is a reference standard on the topic. Good choice. I would ping my sword ping list, but I'm on the wrong computer tonight and don't have it handy. Dang...