With support from the National Science Foundation Dr. Harold Dibble will conduct a series of experiments directly relevant to the understanding of how stone tools (lithics) are made. While modern flintknappers (those who replicate stone tools) are able to reproduce forms found in the archaeological record, most of the fundamental processes involved are not well understood. These experiments, building on an earlier set of experiments also funded by NSF, will extend the results of those experiments to investigate the effects that raw materials may have on fundamental aspects of lithic manufacture and use. Among the independent variables to be tested are (a) different rock types that were used by prehistoric peoples and (b) how subjecting those materials to heating affects their properties both in terms of manufacture and use. The two major sets of dependent variables to be examined include (a) "flakeability" (including the amount of force required to remove flakes as well as the degree of variation -and thus predictability - of flake size and shape produced under identical conditions), and (b) edge sharpness and durability (i.e., two primary considerations for using stone tools for tasks such as cutting and scraping). The results of these experiments will directly address criteria that may have been used in the past for selecting certain kinds of rocks and altering their properties through heat treatment for the manufacture and use of stone tools. Stone tools constitute a principal source for understanding most of the last two and a half million years of human prehistory and constitute a prime source of archaeological data. Researchers wish to understand how they were manufactured and to do this they must understand the properties of the raw materials from which they are made. The research to be conducted has a goal that is much broader than understanding a particular technology or identifying specific processes in the production of particular lithic types. Rather, the goal is to test specific relationships among the independent variables used by all knappers (prehistoric and modern alike) to control the sizes and shapes of flakes. As such, it speaks directly to the fundamental processes underlying the knapping process and is intended to give lithic archaeologists a much better understanding of how these independent variables affect the morphology of flakes. In this way the results of this experiment will be relevant to virtually all geographic areas and temporal periods that yield lithic assemblages. This experiment will also form the focus of an undergraduate course at the University of Pennsylvania in experimental archaeology. This will give them first-hand experience in experimental design and methodology. As has been the case with all research done by the PI, the experimental operation and results will be made accessible to the larger public through a website designed specifically for this purpose (www.oldstoneage.com).
