Wednesday, January 10, 2007

Slicing cut marks on bone: new JFA paper

I've been getting into cut mark studies lately as a result of an experimental archaeology project I got involved with here at ASU. As luck would have it, a short new paper by Haskel J. Greenfield (University of Manitoba) came out recently in the Journal of Field Archaeology

Here, Greenfield uses light optical and, especially, scanning electron microscopes to investigate the morphology of cut marks produced using a range of lithic implements. He uses experimental cut marks on planks of wood to determine the morphology, and is able to identify corresponding marks on archaeological bones from the Early Bronze Age I site of Afridar (Israel). While his archaeological sample is small, he appears to be able to distinguish between the cut marks made by unretouched blades and flakes, on the one hand, and sidescrapers, on the other. He also experiments with various raw materials, namely flint, quartzite and obsidian.

He concludes that "the shape of a tool as a stronger influence on the shape of a cut mark than does the raw material from which it was fashioned" (2006:161), and, unsurprisingly, that "no perceptible differences were observed between cut marks made by unmodified blades and flakes." (2006:153). In his sample, the main difference in cut mark morphology is between unretouched pieces and sidescrapers.

Greenfield shows that unretouched pieces produce "cut marks [that] are thin , relatively straight, and shallow. The internal morphology tends to be consistent: on one side, a groove will descend... steeply and smoothly; on the other side, the groove will descend more gradually, and will have more parallel striations (to the apex of the mark)." In contrast, "sidescrapers leave an irregular and almost wave-like profile." (2006:161). Both patterns are the results of the morphology of the edges of the two kinds of slicing implements.

I liked this paper, though it might have benefited from a more extensive application of the methods on archaeological material. The main drawback, as I see it, is that Greenfield is forced to rely on a SEM for most of this work, which prevents the inspection of large bones, indeed of elements larger than 2-3cm in size. While he gets around this by making silicone molds of the relevant cut marks which can then be broken down to appropriate size for inspection under the SEM, this makes the method impractical for inspecting large numbers of cut marks as well as for identifying the tools used to produce cut marks at lower levels of resolution. While it is clearly important to demonstrate that different tools leave distinct kinds of marks that can be identified at very high levels of resolution, it would also be useful to develop complementary low-resolution methods that are more readily usable in, say, the field lab, something maybe building on the low-res methods of Walker (1978; Walker and Long 1977).


Greenfield, H. J. 2006. Slicing cut marks on animal bones: diagnostics for identifying stone tool type and raw material. Journal of Field Archaeology 31:147-163.

Walker, P. L. 1978. Butchering and stone tool function. American Antiquity 43:710-715.

Walker, P. L., and J. C. Long. 1977. An experimental study of the morphological characteristics of tool marks. American Antiquity 42:605-616.

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