Flint knapping?

[Eterry]

Our farm has 2 creeks running through the property. Along one a sandstone pit was created in the 1940s. Looking through the debris piles we've found many chert looking chips, as from ancient peoples making weapons.
Along the creek are huge, small car -sized boulders of grey stone pushed out by heavy equipment BITD.
I've been told these could be flint material, but I have no experience with this.
I guess a hammer and some on the job experience might be in order.

 

[bldtrailer]

chert(USA flint) forms in limestone and should /may have a white chalky cortex/covering. This is Texas Georgetown

chip off some
1 try to scratch glass (hardness 5 , flint 7 Dimond 10) not your Xs windshield
2 strike with a file flat to see if it sparks
3 try to cleave it into a gun flint size
4 with safety glasses on see if it shatters in the gun lock several test times(to brittle)

 

[M. De Land]

Went to the range today and found some bigger rocks to play with
View attachment 316272
Perhaps it's just because I don't know what I am doing, but this stuff seems a lot harder to work than what they where using in the videos. Here's a few I managed to rough out, not as pretty or consistent as you guys are making.
View attachment 316273

You may need to heat treat them before they will knapp well. Some chert is really ornery until heat treated.

 

[JDBraddy]

You may need to heat treat them before they will knapp well. Some chert is really ornery until heat treated.

How exactly do I do that?

 

[M. De Land]

How exactly do I do that?

Bring heat treating of chert up on an on line search window. There are several how to's on the subject. One guy does it in a crock pot and gets good results.

 

[Eric Krewson]

I saw one video where the guy used an electric turkey roaster to heat threat chert, it will go up to 450 degrees+ if I remember correctly. I looked for a used one on the Market Place and found one for $20 but never bought it.

 

[bldtrailer]

if you want to heat treat here's your guy https://www.youtube.com/@KnapperJackCrafty/videos

 

[JBrandon]

You may need to heat treat them before they will knapp well. Some chert is really ornery until heat treated.

No, don't try heating them if you want them for gunflints.
Proper heat treatment does improve knapping quality, but weakens the stone. For gunflints, you want it hard.

 

[bldtrailer]

I don't need to heat treat Georgetown

 

[M. De Land]

No, don't try heating them if you want them for gunflints.
Proper heat treatment does improve knapping quality, but weakens the stone. For gunflints, you want it hard.

I was told the same tripe before testing it in my own guns. You should try some before making such statements. If there is any difference between treated or natural chert in longevity or quality of spark production I have been unable to distinguish it.
Natural chert that knapps well has most likely been heat treated somewhere along the line in it's life any way.

 

[Eterry]

chert(USA flint) forms in limestone and should /may have a white chalky cortex/covering. This is Texas GeorgetownView attachment 317435chip off some
1 try to scratch glass (hardness 5 , flint 7 Dimond 10) not your Xs windshield
2 strike with a file flat to see if it sparks
3 try to cleave it into a gun flint size
4 with safety glasses on see if it shatters in the gun lock several test times(to brittle)

The car sized boulders pushed out of the limestone quarry have a grey color similar to the Georgetown you posted. The quarry was created in the 1930s/1940s. Next time I'm there I'll take a hammer and glasses and break off a few pieces. I have easily an tractor trailer load of it.

 

[M. De Land]

The car sized boulders pushed out of the limestone quarry have a grey color similar to the Georgetown you posted. The quarry was created in the 1930s/1940s. Next time I'm there I'll take a hammer and glasses and break off a few pieces. I have easily an tractor trailer load of it.

Well that ought ah keep you swinging a bopper or hammer stone for a few years!

 

[Eterry]

Well that ought ah keep you swinging a bopper or hammer stone for a few years!

If I charge what TOTW charges for flint I'll be sitting pretty.

 

[deerstalkert]

If I charge what TOTW charges for flint I'll be sitting pretty.

I have been knapping for a long time. sat down a year or so ago and timed how long it took me to knap GOOD usable flints.
close as i could count on my fingers and toes, i could make about $ 6.00 per hour after all the debitage, band aids, postage.
I can crank out a flint that is ugly as whoopie Goldburg but works in about 45-60 seconds. longer if i have to apply a bandaid.

 

[bldtrailer]

I use cut rest. gloves but there will still be blood /
safety glasses are a MUST flint in eye is more than a bad day

 

[JDBraddy]

Picked up several promising looking rocks at the range today!

 

[hanshi]

Well, like I was once told about the expected results from another skill I endeavored to learn long ago; "It doesn't have (or need) to be pretty it just has to work".

 

[Eterry]

View attachment 318289I use cut rest. gloves but there will still be blood /
safety glasses are a MUST flint in eye is more than a bad dayView attachment 318290

I'm certain that is a fact. I'll keep the glasses handy.
I learned my lesson casting boolits one time, i dropped some sprues in the pot and a piece of molten lead hit my lower eye lid...I thought I was a one eye parrot. Thankfully, prayers were answered when I opened my eyes.

 

[bldtrailer]

just know there is a very low return at first, you're doing well if you get 20% a lot of rock smashing

 

[Eterry]

just know there is a very low return at first, you're doing well if you get 20% a lot of rock smashingView attachment 319136View attachment 319139

I can accept those numbers, with boulders the size of a small car.