can one use stone?

http://flintknapping.com/Library.htm

Hey! CrystalWing and Amon!!! You just gave me an idea! How about if you could get someone who could make you a blade from crystal, like quartz or amethyst or something? That would be REALLY cool! AAANNNNDDDD useful!

I made mention of this in a previous post elsewhere on the site: at a stage I was working with a girl who would literally stub her toe or step on those Magalies Quartz crystals. She'd hang them in her car and put them in jewelry, not knowing WHAT their properties were. All she cared about, was that they were pretty.

She herself, was a Crystal through and through!