Wear assessments of prehistoric instruments

Analysis of wear mechanisms of prehistoric materials are fundamental in many aspects for archaeology to determine their use within a given socio-economic context. Wear test methods have brought significant contributions to the identification of prehistoric tools implemented for the manufacture of stone objects such as vessels, figurines or pendants during the VIIth millennium BC, in Cyprus. Manual experiments conducted by archaeologists have been completed by tribological experiments-scratch test and friction; 3D images and 3D statistical parameters. Quantitative and qualitative analyses of surface states contribute to the characterisation of the wear mechanisms. Our purpose is to characterize contacts between chert, the tool raw material, and different kind of stones. Two case studies will be presented here: a contact between chert and diabase (an igneous rock) and a contact between chert and picrolite (a kind of serpentinite). They illustrate two opposed contact phenomena and wears, on the one hand, between two fragile materials and on the other hand, between a fragile and a ductile material. The development of distinct third bodies during the dynamic contacts have been observed. Lubrication, contact phenomena and surface characterization constitute the basis of our work and the obtained results have brought decisive elements to understand the social organization of a craft activity in a Neolithic Village of Cyprus, Khirokitia, a craft activity which is predominant in the identity of insular communities at that time. (C) 2003 Published by Elsevier Science B.V.