Wednesday, April 4, 2012

A Broken Flaker and Choris Points

Gah - a crack!
So I broke one of my new pressure flakers because I was trying to use it as a punch for indirect percussion.  In retrospect, it seems like it was inevitable, but I thought the walrus bone might be durable enough to handle the forces involved in indirect percussion.  I might have got away with it, but I'd made the bone portion of the pressure flaker longer than the archaeologically recovered specimens and I think that's why it failed.  I thought that the added length would help prolong the life of the tool, but in fact, it cut it short.

It cracked at the weakest point - where the walrus bone flattened to begin the scarf joint.
It cracked like bone.
I think I'll probably glue the fracture closed with epoxy and keep using the flaker for pressure work.  I'm tempted to keep the break open as an example of this type of fracture, but I think I'd rather have a functional flaker than a broken one.  I'll probably avoid using this style of flaker as a punch from now on, even though I think it was the excess length that caused the fracture and that I could get away with it as the flaker wears down more.  Still, as tough as the bone seems, it can chip and is still brittle like any other type of bone.

Two reproductions and the original
I've been continuing to work on the Red Bay and Cape Krusenstern orders.  Here are a couple little Choris style projectile points based on an artifact from Cape Krusenstern.  The original was made on a fine grained, translucent flint or chalcedony.  I used an english flint, because I felt it was a good match to the texture of the original artifact.  Choris projectile points are finished with diagonal pressure flaking scars.  The particular one that I'm reproducing has this pattern, but its not as rigidly perfect as some examples.  Its there if you know to look for it, but it might not be the first thing you notice.  The original and the reproductions are about 5.5cm long.

Diagonal pressure flake pattern
My understanding of Alaskan prehistory is imperfect and dated.  As an undergrad I did take a couple courses which covered the Western Arctic, but since then my focus has been in the East.  The prof who taught the Canadian Arctic course when I was a student at Calgary was a big fan of context - so before we could start talking about the Canadian Arctic we needed to understand Alaskan prehistory.  In order to understand Alaskan prehistory we started in Siberia.  But how did people get to Siberia?  I may have taken the only Arctic Prehistory course on record to begin in Africa.  Still, unless a lot has changed in the last 20 years, the Choris stage is an early phase of the Norton Tradition and dates somewhere around 3000 - 2500 years ago.

Photo Credits: Tim Rast

3 comments:

  1. It's funny because I basically started in the East and moved West. The exact opposite of you. My groundfloor of arctic understanding is Moreau Maxwell's book on the archaeology of the East Arctic, and funnily enough I think one of the best synthesis that puts the west arctic in perspective is by Robert McGhee - 'Ancient People of the Arctic' (rather unfortunate title however - given the title of Gidding's synthesis), and McGhee is an East Arctic archaeologist. Patrick

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  2. Very nice diagonal pressure flaking Tim!

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  3. The Cape Krusenstern artifacts are great to work with. In the East there is a sharp divide between Palaeoeskimo and Thule sites and artifacts. Its interesting to work with some of those earlier cultures that blur the divide and lead up to the Thule culture that eventually spread east.

    I haven't had much cause to try much diagonal flaking, but I like it compared to some other pattern pressure flaking. I find chevron scars are easiest, but the flakes compete with each other, rather than work together. Its like competing wave patterns cancelling each other out. Parallel flaking looks pretty and shows up on Groswater artifacts here (comparably time period to Choris in Alaska), but that has the feel of being almost purely cosmetic. It helps create a uniform surface, but you kind of have to hold back on parallel flaking on small points for fear of taking off the opposite edge. The diagonal flaking lets you take off long flakes that help thin the piece while you work the edge. The pretty pattern is a bit of a bonus. The flake scars removed from each edge help guide the flakes from the opposite edge and once the pattern is set up, its easy to continue. Its definitely something that I want to try more often.

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