Use-Wear Blind Test
The 1st OUP use-wear analysis blind test took place in AŞIKLI HÖYÜK, in July 2009. Obsidian and flint are both used to manufacture tools but these raw materials are really different by their geological origin -one being sedimentary, the other volcanic. Consequently, their mechanical properties are different so that they are constrained in different ways in manufacture and use.
A use-wear blind test, why? The diagnostic characteristics of use-wear are well established for flint, after nearly 50 years of observations performed by hundreds of experts all over the world. Our knowledge of wear on obsidian objects is far less detailed and structured. Our question was therefore how far is it possible using the knowledge build up from flint to establish a diagnostic set of characteristics on obsidian tools.
A use-wear blind test, how? Three use-wear analysts, two of them without any knowledge or practical experience of obsidian tools were asked to perform a blind test on eight obsidian experimental tools provided by Laurence Astruc (reference collection„ Obsidian, Technologies, Functions‟). Each of the tools was analysed by each of the analyst for a restricted period of time (40 minutes) with the help of a stereoscopic microscope and a metallographic microscope.
At the end of this detailed observation, specialists were asked to make comments on the following issues namely the identification of the zones used; the position and movement of the tool; the relative hardness of the worked material, the nature of the worked material, evidence for hafting, the detail of the task undertaken and the precise aim of the operation.
A useful experience? This experience turned to be useful for the three analysts as it gave them pointers for further training. It was also useful for the OUP project as one of its goal is to publish a methodology of use-wear analysis on obsidian tools. In this respect, the blind test and discussion which followed underlined the different research directions needed to define the rules of inference from observations to interpretation, and to define the limits of interpretation.