Anybody knap one of these?

[bjrogg]

These is a chert ball from our local limestone quarry. It is very hard to work but makes a very though point. Most of the artifacts my cousin finds are made from this material

[nclonghunter]

Looks like Hornstone to me...just a guess

I would think a bipolar splitting would be the way to start...I've never worked any myself, but looks like fun.

[bjrogg]

It my be called  hornstone also I was told it's a chert ball and you you look up on e-net. They look just like it some as big as basketballs. I'm not sure fun properly describes how I've worked them took a lot of hammer stone work. This one had a crack stared so I went from there. But I've been told you should they to break in two halves, not sure how to do that I'm just happy to get a piece broke off the thing. I made three nice points from this one.

[bjrogg]

Here's another

[Zuma]

I bet some heat would help.
Zuma

[bjrogg]

pretty sure your right Zuma. I swiped wife's turkey roaster and put one in it helped could even flake the concrete stuff some, its mixed in most of it. NC what is bipolar splitting and how would I do it?

[nclonghunter]

It does look like some circular rings in that one picture which still makes me think some type of
hornstone. I agree with Zuma and you on heating it. Like to see the results.

To do a bipolar split you would put a stone in center below and strike it on top with another rock. It should, might, hope it splits in half leaving two twin pieces. I believe that is how some of the big wide and thin turkey tail points are started.

[bjrogg]

Thanks NC My cousin said he had a whole 5 gal bucket full of these. I guess I don't know what hornstone is I do know it came from the limestone quarry. Do you think I could use a sand filled fire pit to cook them whole or should I try to split them 1st?

[nclonghunter]

I think historically hornstone comes from Tnn,Ky and Indiana...not sure where you are.

As far as heat treating I have no experience. Several on here could answer that better. I believe splitting in spalls and heating is your best option...good luck

[bjrogg]

I'm from the thumb of Michigan They were given to my cousin by the owner of the limestone quarry

[bjrogg]

If you look at the Break wall in the harbor of Harbor Beach you can find them in the limestone. some are basketball size.

[bjrogg]

I just looked up hornstones on the web. these are different than them. These are almost perfectly round like a ball. They have a concrete lime stone shell around them and mixed in with the chert in places inside ball too. The concrete shell is really hard to remove I use very large hammerstone

[le0n]

Do you think I could use a sand filled fire pit to cook them whole or should I try to split them 1st?

definitely bi-polar split & spall first.

otherwise you can have the entire ball self-destruct.

[Chippintuff]

http://www.pugetsoundknappers.com/how_to/New%20Heat%20Treating%20Guide%20with%20Table.html

That stone looks wicked. A little heat could make it nice stuff. However, heating rocks is tricky. It will have to be knocked down to flakes and fairly thin spalls before cooking. Thickness and cortex are enemies of the process. I have opened the kiln to find it full of sand instead of knappable stone. Successful heat treating can be tricky. Follow the instructions in the link above, and I think you may have success.

WA

[bjrogg]

Thanks guys I'm gonna get some more of these from my cousin try the bipolar method and try to cook some in a pit. I took a walk on one of our windmill road found a bunch of pretty promising stuff but it's all been run through crusher most will have inclucsions in it. Who know maybe I'll try to cook some at Marshall.