Heat treating rock (the old fashioned way)

[cowboy]

OK, moderators or admin. Could you please delete that first one? I kinda hit enter or something and it went before it's time .
  Allright, I have sent this to several of you folks - thought I'd share it with everyone. I took a series of pictues for a friend that's into knapping to help explaiin how to treat his flint - this is what I came up with through my trials and tribulations. Just a side note - I tried a toaster oven (it didn't work). 
   This is all TX stone that I have worked with (pederanales)- think it should work with most flints or (cherts) but don't think it'll work with novaculite.
   To start out: You need a good bed of sand, or sandy soil (works best if you have powder dry dirt). Acually not for sure if you NEED sand, but that's what I have and it works.
   This is gonna be short due to lack of room (the pictures will help). You'll want a bed 1" deep, take your spalls and wriggle them into the bed. Hoe a bunch of dirt on top and then start working it around until you have what resembles a volcano (with a rim). Pack your dirt down, by walking on it. Measure the dirt covering the rocks - you want somewhere between three and four inches after packing (the rim of the volcano just holds the coals in later). I start my fire at dawn, keep it going HOT AND STRONG until sunset. Don't even think about digging them up the next morning, let em set for two days or so, and if they didn't blow up - you'll have some nice (glasslike qualities but much tougher) flint to work with. Hope this helps some of ya'll .



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[cowboy]

Few more.

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[Justin Snyder]

Thanks Paul, I need to heat treat the rest of that Texas stone I got.  I tried making a point out of the untreated stone the other day.  Man that is a lot of work.  Justin

[Roger]

Excellent post Paul....Them sure is some purty points!

R

[cowboy]

You bet Justin - I know . Hopefully you have good results on your first attempt - if your like me, you'll have a lot of good knappin stone and some blowed up s$!& . Let us know how it turned out whenever ya get the chance - if you need more to play with?............
   Hey Sparky! good to see ya here!!! Yep, them's some killin points allright. Made em whilst I was cookin nother batch. Friend came over and made me have some beers, so tha knappin stopped right there - well, right after I broke the next one . That one on top is Brazos river chert, you can find plenty of rock in there if ya look - and once it's heat treated It'll work as well as any.
.

[Mickey]

Man, that is one sweet fire pit.

This couldnt have come at a better time Cowboy. Just got a bunch of chert in that needs to be cooked. Now I see how to do it. Thanks a bunch for posting this.

Just starting knapping and it's hard to believe you get those beautiful points out of those wavy potato chip looking spalls like the one laying on the stump. I have a lot to learn.

[cowboy]

Hey Mickey - glad to see someone taking an interest in my post . That was originally my trash burnin pit - I found a way better use for it. Thanks for the compliment on pernts (borrowed that from Bob). If you or anybody need any other tips - I'd be glad to help. Just so's ya know, I'm that guy at OJAM that knew ya but couldn't remember your name - you know how us new guys are .

[D. Tiller]

Thanks Cowboy! Now I understand what to do. Now to find the time! As the song goes "Time keeps on slippen .. Into the future!"

Now tell us about your tools! Thos are a bit different than my pressure flakers. Whats with the flat ended one???

David T

[cowboy]

Hey D: Yep we could all use a little extra time . That flat tipped one in the pic is my edgeworker and notcher, tha flat end I use to notch - it's just a 1/4" copper wire hammered down flat, make it as thin as youd like your notches to be wide - those points in the pic's don't have narrow notches. The other end is the same wire ground to a tip for edge work - the rubber pad is what I hold in my left hand while holding the Ishi or hand flaker in right hand to run pressure flakes off the peice. I could almost wright a book on the whole process .

[makete]

Some dumb questions. Why is it important to heat treat the stone? Also can agates be used for points? Found a couple of stones about 2 or 3 lbs each on the shore of lake Superior and was wondering if they could be used for something.

[cowboy]

Makete: The heat treating changes the stones composition in some way. Most all knappable stones have varying amounts of quartz, which is (I believe) the part that changes the most. The high heat (it has been said) either rearanges the atomic structure of the stone, or somehow fills in the microscopic gaps between molecules - thus allowing the shock wave of pressure or percussion to travel further through the stone.
     I'm not sure on the agate, it seems like it would be slick enough to work. I have found points made of all quartz - really grainy terrible working stuff, they weren't thin but appeared as if they'd work - that's all those people had in the area. I have walked the shores of lake Michigan on both sides and didn't find anything I could use.

[DBernier]

Cowboy, nice thread. Now I don't have to post mine. On the HT, one point also, on the granite like material, the HT seems to make it "easier" to remove material. Another given, especially Florida Coral, is the unbelievable colors you get. I am converting one of my table saws to a 10 inch slab saw for processing a bunch of material. Hope to HT that stuff during the winter months.
  On the quartz deal, a lot of the "old" Northeastern points are made of quartz. They are chunky and not very sharp. Could be worn down thru the ages. Again, nice thread and you do absolutely beautiful work. Vinson says to say hello.

Dick

[cowboy]

Thanks Dick. That's right on the coral, beautiful colors - a lot of this TX stuff will change color during HT also, Just too many variation's to mention. I have cooked some of the quartz (quartzite?) cobbles that I've found - It'll actually make a point, but the edge crumbles too easily to run long flakes.
  I'd like to hook up with you and Vinson again - matter of fact we have another job going on in NC right now, maybe I'll make a run out there. Hmmm......... East or West - got one up in WA state too.

[D. Tiller]

Hey! If your arround Whidbey Island WA give me a ring.

David T

[mullet]

  Makete,Agate makes some nice points.Most I've tried works real well after heating in the 450 to 500 dgrs range.