Cooking rock

[bjrogg]

I'm planing on cooking some rock. I've done this before with my wife's turkey toaster "shhhh don't let her hear that" I cooked some local stone with mixed results some improved and some no change. What I'm more concerned about is that I cooked some Texas Flint for my brother once. Some showed really good improvement but unfortunately more than an acceptable amount became very brittle and would shatter. I'm planing on cooking some Flint River butterscotch. The process I used last time was placing layers of dry sand and spalls in roaster smaller one to outside larger to inside. I then turned temp to 200 for 24 hrs the. Ramped up temp about 75 degrees every hr till 475 I also removed liner. I left about 14 hrs then turned heat down over 4 hrs and let sit for 24hrs. I don't  know if that was to high of temp for Texas Flint? From everything I'd seen they tried to get the highest temp they could from turkey roaster. I'd like a good recipe for cooking butterscotch flint fiver if anyone has one. Thanks
BJ

[Zuma]

I pulled up Ed's thread Red Jasper
Chaek it out.
My recipe works for Edwards, Rough Fnglish,
some coral, most jaspers and Butterscotch
Flint River.
Zuma

[bjrogg]

thanks Zuma I swiped the wife's turkey roaster this morning when she wasn't looking, have to remember to get it cleaned up and returned before sons graduation party in 3 weeks. I filled it up mostly with local stuff that I have worked raw put some flint river on top all surrounded by dry sand I used to cook before. Hopefully this sample batch works good, who'd think you could screw up cooking rock but I'm kind of a barbecue guy. i'll let you know how it taste I mean works lol
bj

[Knotty]

When you think you don't have parents controlling you.. Here comes the wife! 😂

Cooking rocks is a new thing for me, never heard it, I guess it makes certain rocks easier to knap?

[bjrogg]

Yes knotty the primitive tribes used fire to alter the rocks properties and make it knap better. Lord knows I need somebody to keep me out of trouble lol.

[Knotty]

Great, thanks for the information!

[Chippintuff]

Your process sounds good, but the temp was too high for all that fractured. A lot of Texas rock will blow up if you go over 400, and some will even blow up if you go over 350. Generally the darker stone is less tolerant of heat. Lighter stone can go higher. When there is any doubt, cook at a low temp; after cooling, check and recook any rock that is not ready, but at a higher temp. Keep notes on what required what temp. Sometimes trial and error is the best gauge provided you start low and work up till a good result is reached.

WA

[bjrogg]

Thanks chippintuff it allway registers when you screw up just nice to know why. I'm pretty sure this local stuff can take a lot of heat. I don't have any $ into it. I don't know anything about the flint river but Frank said about the same as Zuma so hope it turns out good. Didn't put a real lot of flint river in.
Bj

[Zuma]

Chip has good advice.
I wrote this for the other thread so take it with a grain.


I hear ya. I have always been stone poor.
My theory is cook cooler and shorter than recipes
that are on sites that cook and sell rock.
I think they are way off. Just to discourage you
from doing your own or getting you to blow it up.
I have never had problems cooking in the household oven.
If you have a lid on your pan you won't blow up the door glass
or the elements.
Sand helps even the heat so thin and thick get more even heat.
500 degrees will do fine on your butterscotch.
try my times above. There pretty short and you won't blow anything up.
Zuma

[bjrogg]

Thanks Zuma I just turned off the roaster. Went by your times my wife's roaster says it goes to 450 so I should be safe. Now just let it slow cool and see what comes out. I think her other roaster goes to 475 if I need a little more heat

[Outbackbob48]

bjrogg, just because the dial says 450 doesn't mean it is , I usually probe around thru hole in lid with meat thermometer to find a truer temp, edges of roaster seem hotter than middle, be careful with flint river, ramp up slow most flint river can have lots of moisture trapped inside it. Bob

[bjrogg]

Thanks outback I know last time I cooked rook I left at 200 for quite awhile.

[Chippintuff]

All good advice here. Turkey roasters are notorious for achieving different temps than the ones on the dial. I wired fiberglass insulation into the lid of my turkey roaster. Then I drilled a few holes just big enough to allow a meat thermometer to get through. The longer I leave mine at a given temp, the higher the temp goes. If I top it out at 450, within 3-6 hrs after I put that setting on it, the temp will be at it's true max. The middle of the roaster will have temps just a little higher than the dial says. The sides, and especially the ends, get hotter. The last batch I cooked I set at 450 for the max temp. Twelve hrs later the middle was 475 and the ends close to the edge were 525. Monitor your cooker to find out what it is really doing.

WA

[bjrogg]

I tried some of flint river and really couldn't see any difference. I think I'll turn to 200 over night then start ramping up in morning leave soak a little longer.

[bowmo]

http://gemstone.smfforfree4.com/index.php?topic=3392.0;wap2