Not that it really matters what this stuff is,as I think it will Knapp, and even be better if heat treated,but id like to know for curiosities sake. I live in western Pennsylvania just north of Pittsburgh. I've walked thru several streams in my area never finding anything that will flake. Until today when I was down at a park with the family I found this stuff that had been brought up from some intense flooding and record rainfall a couple weeks ago. It turned up massive piles of stone and destroyed some things as well.
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Here's the small pile I gathered in one spot before we had to leave. Ill be going back for more if this stuff works.
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Some of it was better than others,but this one pulled a nice flake with a hammerstone. I was squatting in a island pile of rocks in the creek hammerstoning a couple trying to make a head. A couple came up and asked how I got across,and never asked what I was doing,but they had the look on there face like,what the heck is he doing....lol.
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My guess is its def volcanic in origin. And my guess is some form of rhyolite,maybe metamorphosed?
Thanks for looking and to anyone who can id it. ....Chris