I've been playing around with some glass lately, just pressure flaking plate glass, wine bottles etc. I don't really call that kind of stuff knapping though. Cowboy sent me some of that tough stuff from Texas and I have succeeded in reducing it down to pea gravel with nothing to show for it. I just haven't been able to knock a slab off of anything big enough to get a point out of it.
DanaM sent me a couple chunks of obsidian the other day and Presto! So far I've managed to get three decent points from it, my first actual "from a rock" points. I need to get my hands on some more of that stuff. It won't leave you as frustrated as that Texas flint.
I won't give up on the tuff stuff though, but I have no problem crawling before walking
The first three pics are obsidian. The third and fourth are glass baking dishes. Those Glas-Bake and Anchor Hocking dishes actually seem tougher than obsidian. I wouldn't hesitate hunting with points made from it at all.
Btw, thanks again Cowboy and Dana!
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