Obsidian nodules

[karatekid069]

I was wanting to make one last trip up to the obsidian mines before the snow flys. My question is can u tell by looking at a nodule if it is good quality? Does size matter? What do knappers look for in the rocks they pick up?

[Trask]

I was wondering this too..I took a hammer with me and busted open chunks..You'll see my scatter all over Big Springs lake bed

[Cannonman17]

You can tell the quality sometimes by looking at the outside but it takes a lot of experience. Just try to find pieces that have as few inclusions as possible, watch for cracks, even small ones, hold up to the light to look for flaws, the more pure a piece appears to be the better off you will be with it.

[KEVINSMITH]

A bigger nodule means you can get a larger spall off of it. The larger the spall the larger the point you can make. I personally like the largest piece I can get. That way I can get some nice sized spalls. When I start to reduce a large spall you will get some nice sized flakes that can be turned into other points. Just my two cents. Do you do much knapping Karate?

[karatekid069]

I have not yet. I figured it would be a good winter time hobby. The spot I am talking about has ob anywhere from a golf ball size up to medium melon size. I will just grab the big chunks and work from there =)

[KEVINSMITH]

Melon sized would be a great place to start. You should be able to get alot of workable material out of a nodule that size. Good luck!!!

[drdave514]

I don't know if it works this way for Obsidian but many types of material around here are supposed to be hard to work with if they've ever been frozen as the fissure lines are too numerous then. The idea, as I understand it, is to get material that is in the ground below the frost line.

[Stonecracker59]

I always take a hammer and make a small chip to tell for sure

[DesertWalker]

Doc, you got it. Most of the knappers I know prefer obsidian that has been buried somewhat, or larger pieces. Otherwise, outer spalls fracture too easily.

[Kevin Young]

You really shouldn't use a steel hammer, if you have to it should be anealed(sp) to soften it up some .....Causes alot of shattering down inside the nodule that you do not want. Copper is the preferred metal. Also a word of advise...Better have some good goggles and leather gloves, some super glue or needle and thread handy too. If you get a chip in the eye it can ruin you forever. Obsidian will cut your hands or anywhere else on your body like a hot knife through butter. your gonna bleed, it's just a question of how much. Cannot be too careful with this stuff.