mysterious black flint

[Runner]

Yes, I have saws and would be interested in cutting a couple of experimental flints out a small nodule for you. I would also be interested in some of the Texas material to make some test flints out of.

I am using a light gray transluscent chert found locally. It does not break to the razor sharp edge that obsidian or some flints do, but it is very durable. I sharpen on a lap like you would a chisel edge. I made a pretty strong attempt to knap a few flints from it, but it is beyond me. Haul off and hit it with 1.25 brass bar and if it breaks, it breaks into chunks, not the flat blank you need. After trying with it for a while, I went looking for something else to test my procedure on to see if it was me or the stone. I grabbed a peice of obsidian with a purple pink sheen in it. Being use to pounding on the chert, I hit it way too hard and two pieces stuck in my hand pretty well when a large piece shattered on me. I did get a nice percussion bulb shaped flake for Stone Hands to work later tho. It is way too nice for me to be messing with yet. I should not have even touched it until I have a lot more practice.

At the Old Mines gathering I was given a fist sized lump of very high quality black flint with a brown rind like you would expect to see on the outside of a weathered agate. It throws sparks very very well and would likely knap very well, but I promised to cut a couple out of it with the saw. I am considering cutting a couple of knife blanks out of it also and seeing what a good knapper can do with it. It is no where near as durable as the chert I am using is, but it breaks to a sharp edge and throws sparks that are hard to match with any other stone that I have tried.

 

[musketman]

I grabbed a peice of obsidian with a purple pink sheen in it. Being use to pounding on the chert, I hit it way too hard and two pieces stuck in my hand pretty well when a large piece shattered on me. I did get a nice percussion bulb shaped flake for Stone Hands to work later tho. It is way too nice for me to be messing with yet. I should not have even touched it until I have a lot more practice.

You are lucky you didn't get cut to ribbons, obsidian is volcanic glass and a single flake is 500 times sharper that surgical steel...

That is why obsidian blades are used in eye surgery, makes the cleanest of cuts outside of lasers...

BTW, I hope you use safety glasses when knapping flint and other stones, nothing says pain like a hot chard in the eye...

 

[Twisted_1in66]

**SNIP**The flint is basically just a sharp edge. You can use most any rock that you can knapp or chip to a sharp edge - like chert, quartz, granite, agate, fossilized bone, etc. **SNIP**

Nice post and almost all of what you said makes sense. However, in the list above, you have granite listed as a rock that you can knapp. I'd really like to see that. I've used granite as a hammerstone when knapping big nodules of something else, but it doesn't have the crystaline structure to give you the conchoidal fracture like the rest of the rocks you mentioned. Plus, it's hardness rating is through the moon.

Though I suppose if you could manage to get a sharp edge on it, then it would spark. Sharp edge on sandstone won't do much but crush, but if you did get a sharp edge on granite I'm sure it would. Just has to be hard enough to srip off fine slivers of the frizzen and there's no question it's hard enough for that.
:imo:

 

[Runner]

With the high feldspar content of granite, it is harder than any of the normal stones used for this purpose. A flint ground out of granite might be wonderful because it is interlocking crytals at different angles that provide different hardnesses and cleavages in each crystal face. Wear from impact should stay rough enough to make sparks well after it starts to dull a little. A piece of Jade might be even better. Getting the correct shape and edge on the harder stones that don't have conchoidal facture is the problem. There is no good way to do it short of diamond saws or wet grinding.

 

[Twisted_1in66]

With the high feldspar content of granite, it is harder than any of the normal stones used for this purpose. A flint ground out of granite might be wonderful because it is interlocking crytals at different angles that provide different hardnesses and cleavages in each crystal face. Wear from impact should stay rough enough to make sparks well after it starts to dull a little. A piece of Jade might be even better. Getting the correct shape and edge on the harder stones that don't have conchoidal facture is the problem. There is no good way to do it short of diamond saws or wet grinding.

You know, if you could make the edge on it, I bet it would last a gooooooood loooooooonnnggg time!!

 

[brubincam]

if i put my wifes diamond ring in the cock would that spark??? :shake: :shake: :shake:

 

[Runner]

I have a flint cut out of garnet here!

 

[big bore 75]

hey squire robin thats interesting to see how flint was also used in my familys old country how old is your church? its quite beautifull. bb75

 

[robinghewitt]

The church was added to as the town became more prosperous, the earliest parts are just coming up to 1000 years old.

There's quite a bit about it on the web. Here's a link :thumbsup: Click here