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Redbear
03-16-2008, 03:09 PM
Alright I have been breaking every rock I see on the streambed by my horses stables and can't find one rock that looks knappable. No flint or smooth surfaced under the outer shells so how do you tell which ones are knappable? I know some have to be heat treated but is there anywhere to look to ID these?

canid
03-16-2008, 07:16 PM
knappable sedemantary stone such as flint, chert, etc can be recognized by thier chalky, powdery cortex [outer layer] of various, sometimes mixed color and often smooth [but often gritty, grainy] texture where broken. while this texture dosen't always look shiny and is seldom glassy, it will generaly feel smooth.

http://www.ohiohistorycentral.org/images/multicolored_flint.jpg
http://wildlife.vigay.com/fossils/i/flint4.jpg


below you see the grainy texture, but flaky cleavage where the rock is broken:
http://www.beg.utexas.edu/mainweb/publications/graphics/chert400.jpg

when found in river beds, the chalky cortex is usualy knocked off and they will appear as sometimes broken nodules of dull colored rock like other round river stone:
http://www.pantgwynquarry.co.uk/images/pictures/flint_lg.jpg

then there are the knappable volcanic stones such as obsidian, which have a dull, knobby, rounded shape and a flaky cleavage where broken exposing a glassy, slippery texture. these are found in volcanic flow deposits:
http://tbn0.google.com/images?q=tbn:Q_69v9WFaohATM:http://gwydir.demon.co.uk/jo/minerals/pix/obsidian2.jpg

FVR
03-16-2008, 09:03 PM
Just keep break'n rock and you will figure it out.

I broke so much rock when I started my wife thought I was a rock. I found flint in the flint river but it was very un workable. Mother nature had cooked it too much and just too many fractures.

I was walking into a yardsale with my wife one morning, she looked down, picked up a rock and said " FVR, why don't you make a point out of this?" Now, I took it said "yeh, okay dear" and sticking it in my pocket. She was looking at something, I was bored and I pulled it out of my pocket and inspected it, Freak'n black flint, beautiful, palm size chunk. As we walked out, I was just in aw, this guys whole rock driveway was flint.

I asked him if he minded that I pick up a few pieces of his driveway, he did not care.

Made a few good points.

You just never know.

Other good knappable materials; beer and wine bottles, stain glass, pane glass, thick glass bottoms, glass ashtrays (excellant), broken plates, broken glass from those glass tables both dinning and end table (awsome as it's thick and if you are lucky, it's smoked).

Don't get stuck in the mindset of only rock is knappable, also, don't get in the mindset that anything you knapp has an end result as a arrowhead.

One thing I do, some think I'm weird, but I pay attention to each and every shape of what I am knapping. I may start out to make an ax head, but the more I look at it, the more it is telling me that a bowie blade is what it needs to be.

I have a few blanks that I knocked out years ago, I have kept them as blanks. Why, because that is what they are suppose to be. One in particular, it's a chunk of coastal plains chert, pretty brown, would make a beautiful arrowhead. But, it's been in my possibles bag and has started more fires than I can count.

One piece of flint that I got from Israel, when I was banging off the outer layer, I noticed that if I leave the existing outer layer, it fit my hand perfectly. I put a 3" long edge on it and it has gutted and skinned deer, hogs, turkeys, a few otters, and a raccoon. It was bound to be tool rather than an arrowhead.

This is my philosophy, some think it's strange, but it works for me.

Redbear
03-17-2008, 08:51 AM
Thank you guys for the input. I didn't realize that rock didn't have to be smooth to knap. I am assuming if the quartz I am finding is full of fractures heat treating it isn't going to help, only crack it worse? As for the other gray stone I am finding which is smooth but grainy, will heat treating help or can I try to work it in its current condition?

Beo
03-17-2008, 08:56 AM
WOW... alot of good info thanks.

canid
03-17-2008, 09:18 AM
yeah; take FVR's advice about the glass. most of my points are former sierra nevada pale ale and arrogant bastard bottles.

ditto about the shape. let the shape and propensities of the piece determine the tool it becomes. i've broken too many pieces trying to knock off bulbs that where very prone to hinging just because i wouldn't except that they weren't meant to be a knife, or where no longer suitable for that purpose after the work i'd done on them.

several pieces of slab waste [edges cut off by somebody making cut preforms] i have have become planes for woodworking. a few are even saws.

canid
03-17-2008, 09:23 AM
a tip for you though. wear eye protection no matter how little work you intend to do.

i keep telling myself 'i don't need to put them on, i just want to get this roughed out for a quick sec.' then getting drawn in and now i have the tiniest flake of obsidian sitting just inside my eye near the tear duct. itches like crazy for the last 6 hours or so.

Rick
03-17-2008, 09:31 AM
Ooh. Thick of all the micro scratches that are taking place each time your eye moves. Glasses, glasses, glasses. Protect your sight.

canid
03-17-2008, 09:32 AM
with my luck it'll work it's way inward and start going to work on my optic nerve ;)

trax
03-17-2008, 11:53 AM
FVR...your wife calls you FVR? :D

FVR
03-17-2008, 07:29 PM
No.................

She calls me arshole, butthead, bastard, **** for brains, dumb****, did I mention arsehole, and honey.

Redbear
03-17-2008, 09:09 PM
Thats gotta be love!