Primitive Archer
Main Discussion Area => Flintknapping => Topic started by: Ed Brooks on March 27, 2014, 12:07:36 pm
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I think I found a piece of red jasper about the size of a hard ball (base ball). I'm going to try to cook it in the ground. The big question I have is should I break it down into smaller pieces before cooking? What should I do? Thanks in advance. Ed.
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Cooking rock in the ground is pretty much a lot of work.
With such a small quantity it may not be worth it.
I live in northern VA where there is quite a bit of jasper and I cook it in the oven.
I just cooked some coral last night for the first time. I think I have to either cook it longer or hotter.
What I would do with your nodule is split it as best you can and see if it is truly cryptocrystalline. Then put a thin piece on the burner and heat it until it turns color.
I seldom find red jasper. It is usually a yellowish color and turns red when heated.
If it looks worth cooking then get a ovenproof pot with a lid (metal) and dry sand.
Put the rock(s) in the sand in the pot. Heat at 175 for 1/2 hr. with the door of the oven slightly open to let any moisture out. then increase the temp 50 degrees every 45-60 mins. till you reach 500. Soak at 500 for 60 mins. or so then reduce the temp 50 degrees every 45 mins. or so till you reach a constant 300.
You can then turn off the oven but don't open the door for several hours 5-8 at least.
Zuma
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You should at least strike off a flake and see if it is even worth the effort. If it is all fractures, you will be glad you didn't heat treat it.
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If it looks to be good material might think about getting it cut into slabs, I have no experience cutting stone so maybe to small or not worth the trouble to slab it.
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Thank you guys for the feed back,
Zuma thanks for the times and temps, I'll have to run that one by the wife ;), when I crack it open to see if it's cryptocrystalline. I have to ask what is cryptocrystalline? does that just mean it is a knappable rock, supports a conchoidal fracture?
Knapper, it seems to be a solid piece for the most part, I will find out when I make gravel out of it :laugh:.
Outbackbob48, I don't know anyone around with a rock saw so I will just smash it into smaller pieces, as I think this is too big to heat as is.
I find a lot of tools and flakes around here made form rock that looks like this. Thanks Again Ed.
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I have one.
VMB
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I have one.
VMB
Hello VMB, I have got this piece of rock in some smaller pieces now, when the weather gets better I'm going to attempt to heat it in the ground. Ed.
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Too bad u don't have a small slab saw..or a tile saw if its big enough.. Then u can get multiple pieces with least waste..then heating would be a breeze.. Good luck...
Russ
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Sorry I never replied Ed ???
I brought this up for BJ
Ed your rock looked a little jasperish but I think we
can see why you never persuaded heating it >:D
A lot of the local jasper here is similar and unusable.
Zuma
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Thanks Zuma, it rained yesterday might get a chance to cook some today. Have to see if I can sneek the wife's turkey roaster again. Do you think I cooked the Texas Flint to long or is it just a different critter? Maybe something else? Sure don't want to ruin this flint river it's hard enough for this old farm boy to spend good money on rocks. Lol