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PA Jasper

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Wolf Watcher:
If this jasper is like some of the ones from here and Mt. St. Helens it takes quite a bit more than 450 to get a glazed cook and may even turn colors.  Looks like some very interesting rock!  Joe

caveman2533:
here is a better picture maybe

Zuma:
Joe, the east coast Jasper's I am familiar with can knap
pretty well raw a lot of times. It runs the gambit in workability.
 I heat mine at 500 and soak it just for an hour or so.
It can produce a real slick surface at times.
 It can be reheated if it gets tough deeper in as you flake it.
All raw colors from mustard to black. Choclocate is my favorite.
These are VA jasper but very similar to PA.
Zuma

caveman2533:
Yes much of our jasper needs no heat and even 400 can be too much for some of it. I must correct myself also as this was heated twice. The first time to 460 the second went to 510 and it could go another 50 or 60 without making it too slick. The problem is some of the darker color like is on the tips and bases will not take that much heat

Wolf Watcher:
Back in the 50s when I was working on my Father-in-law's ranch just east of the Yellowstone boarder I was able to hunt for artifacts made by the Sheepeater Indians.  They made gem quality points mostly from local area jasper.  Any spall left in a chipping ground was mine to work on.  It always surprised me at how tough a shiny spall could be.  Over the years I found lots of red colored jasper chips and wondered where they came from as the places where there were spalls there was never any spalls of that color.  The country has lots of volcanic rock cliffs and in them I could find agate and jasper nodes often much bigger than my fist.  I learned that the Indians would spall out the nodules at the source and would pack them back often many miles to a chipping ground usually where they camped.  The chips I would find there were not the same color as the spalls.  After many years people like Waldorf started telling about heat treating rocks that I finally discovered that the jasper from the spalls would completely change colors when cooked.  I think it has to do with either copper or iron oxides in the stone when it solidified eons ago.  I know that not all jaspers respond to cooking the same way and am convinced that jaspers cooked centuries ago will eventually return to their original Rockwell scale.  My opinions are not necessarily scientific, just ones I developed over the years.  Joe

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