When a stone flake is used in specific applications, such as sawing
or whittling, distinct wear patterns are formed. In addition, unique
patterns are also formed by the surface on which the tool is used. Wood,
meat, hide, and bone all leave dissimilar scars on a lithic device. Modern
archaeologists have devised a method, called use-wear analysis, in which
attributes from archaeological remains are compared to modern examples
whose function is known. This allows archeologists to determine the
function of a prehistoric tool by its wear patterns. The purpose of this
experiment is to note the wear patterns caused by sawing wood, and to
ultimately decide if use-wear analysis is indicative of the function of
past tools.
A small obsidian flake would be used in this experiment. It was
approximately forty-eight millimeters long, thirty-four millimeters wide,
and seven millimeters thick. From the ventral view, the left side was
serrated. This seemed like the most appropriate side to use as a saw. A
small round twig, a centimeter thick, from a local deciduous tree was used
as the wood subject. The exact species of the tree is unknown; however, it
was a very hard wood and a light brown/tan color.
Initially, medium pressure was used on the flake and it was moved
in bi-directional strokes across the stick. After about thirty strokes,
the use edge angle prohibited the flake from cutting further in to the
stick. The cut was roughly three millimeters deep and three quarters
millimeters wide. It could be determined that a tool, in this particular
shape, could not be used as an effective saw. However, use-wear patterns
could still be inferred. The flake was moved to another portion of the
stick and the same process was repeated. This time the cut was only about
two millimeters deep, before termination. Also, small pieces of obsidian
were left in the cut and many more small pieces were mixed with sawdust on
the table. The flake seemed to be deteriorating quite quickly. In
addition, the pressure required to make the second cut was far more than
the force needed for the initial cut. The gradual increases in pressure
continued in this manner until nine cuts were made. After this, the saw had
been dulled to the point of being ineffective. In all, the procedure
required roughly four hundred strokes, and wore about four millimeters of
the left side of the flake.
The most prominent change to the flake occurred on the serrated
edge. Not only had it lost nearly four millimeters, but also the serration
was rounded and no longer sharp. Furthermore there were many places on the
flake were fairly sizeable pieces had come off. This is not surprising
because obsidian is known for being brittle. Many of the pieces had fallen
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