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[amrap1]

I always thought Flint was a tan rock that Native Americans somehow chiseled into an arrowhead. When I went to the Native American Pow-Wow in Mohican State Park I saw people banging white/tan rocks into arrowheads. After my 4 hour YouTube course about flint I learned that Ohio Flint comes in many different colors.  The flint has such a diverse color pattern in it's raw form. I read about Nethers Farm and went there today. What a NICE LADY that owns it. This is just a sample of what I brought home. I bought 10 lbs for $10. (about 20 rocks)

Ed

[amrap1]

Brought them home and tried a Harbor Freight $44 wet tile saw (WITHOUT any guides at all.. borrowed from a friend).  1st problem is that the water flies everywhere. 2nd problem is that it's hard to keep a weirdly shaped rock straight while cutting. I cut different medium sized pieces into "tumbler size" rocks and let's see what happens.

[R.U. Sirius]

I know, right? At what point do we call it "jasper"? Its cryptocrystalline silica, it shows interesting colour patterns, so... quacks like a duck and walks like a duck.

And speaking of silica - it's not just water flying off that tile saw. Silicosis is a real risk. Avoid doing things in a way that creates lots of dust, including second-hand dust after droplets have evapotated. Wear appropriate PPE. Mop floors and surfaces that have been contaminated. Wash clothes immediately after messy cutting.

[amrap1]

And speaking of silica - it's not just water flying off that tile saw. Silicosis is a real risk. Avoid doing things in a way that creates lots of dust, including second-hand dust after droplets have evaporated. Wear appropriate PPE. Mop floors and surfaces that have been contaminated. Wash clothes immediately after messy cutting.

I've never heard or read about that. I guess I have a lot more to learn!

cough cough
Ed

[Felicia]

That sort of thing is why I invested in a trim saw, less mess, used ones can be found. I admit the price probably won't match that of the tile saw. Cutting the weirdly shaped rock - place it so that it is stable as possible, flattest part on bottom ( you know that ). You'll have to take it slowly, with a firm grip. With practice you can learn to feed the stone quite straight if you don't have a vice. I do the majority of the pieces this way.  Good luck and lots of fun.

[Slabbercabber]

It is all called Ohio flint, but in fact the actual flint is in a separate layer.  The colorful stuff is really jasper.

[R.U. Sirius]

It is all called Ohio flint, but in fact the actual flint is in a separate layer.  The colorful stuff is really jasper.

I'd like to understand how and where you draw the distinction between flint and jasper, chemically and/or geologically. It's opaque microcrystalline silica, with conchoidal fracture, etc. Is it just based on colour?

[amrap1]

I would think it's based on the majority material. I've never seen an arrowhead made of Jasper. Quartz seems like the best example of this. "Smoky Quartz" has another mineral included, but it's still Quartz....

[Slabbercabber]

The line is drawn at the spark point.  At some indeterminate point the amount of alloy gets to be too much for the material to spark reliably.  At that point it can no longer be classified as true flint.  The breakage will confirm this as well.  True flint will always have concoidal fracture while jasper may not.

[vitzitziltecpatl]

I've always wondered about the small amount of Ohio "Flint" we have here. Multicolored rough without conchoidal fracturing. The comment that the flint there is in distinct layers separate from the rest of the material makes sense. I hadn't heard that before.

Our rough does have colors and patterns like what I've seen identified elsewhere as Ohio Flint. Another question I've always had relates to the colors of the rough. Is this rough routinely heated to improve the color?

[irockhound]

All this is very interesting since i have never collected flint.  I have read that many material are heated to make them more workable like for flint knapping etc making them more brittle.  Also I read long ago that in India they heat the material prior to working it into beads.  Are there any downsides to heating if it ends up for cabbing such as increasing chipping in lower grit wheels?

[Slabbercabber]

I have a very large amount of colorful Ohio flint as well at the actual flint and what they call nellie blue flint (steaks of blue quartz running through)  I've tried heating the colorful stuff with no discernible effect.  I don't work flint so I can't comment on that.

[vitzitziltecpatl]

That's why I have so many questions about this stuff, too. We never bought any until a couple of years ago, and only cut a couple of testers just to see how it would polish.

The variety of colors and patterns is cool, but it's all so varied most people can't easily identify it just by the appearance. That makes it a tougher sell compared to things people are more familiar with.

I'd heard of Ohio Flint for a long time, but until I saw photos of the more vivid patterns it was "just flint" to me.

[Felicia]

The colorful stuff can fracture conchoidally, depends on the quality. The Ohio Flint (or whatever) is metamorphic, and on rare occasions contains fossils. Usually seashells. Occasional streaks of silver are also found, near the dark bluish areas (tiny). I think the line between agate, jasper, and chert is opacity. These stones can be any color. Or many.

[vitzitziltecpatl]

Yeah, some of the pieces we have look "glassier" than others. That's why I was hoping someone could describe how a heated piece might differ from an unheated piece. Or if it's just the difference between grades as they are in their natural state.

Ohio Flint is just one more example of material I wish I knew more about.

Thanks for the tip about possible silver content. That certainly makes the material more interesting!