Experimental approaches to the development of use-wear traces on volcanic rocks: basalts

In this paper we present the experimental results obtained for the formation of use-wear traces on four types of basalt rocks from the Olduvai Gorge (Tanzania) and one from the Deba River (Spain). The objective of this study is to create a reference collection that will allow the posterior analysis and identification of archeological use-wear traces on lithic industries made on these different types of basalt, such as the Acheulean lithic industry from Thiongo Korongo site (TK) (Olduvai's Bed II, ca. 1.353 +/- 0.035 Ma.). This study includes five types of basalt, under the objective of understanding in more detail the formation of the use-wear traces. Additionally, we include their individual petrographic, chemical, and traceological interpretations, allowing for an assessment of the intrinsic characteristics in relation to the development of use-wear. The final step of this process includes microscopic analysis for the detailed characterization and description of these use-wear traces. The results obtained reveal the internal structure of basalts as a significant conditioning factor in the development of use-wear traces. Despite this, we have been able to establish several criteria that discriminate between actions and different worked materials. These results offer a fundamental experimental basis for the future interpretation of use-wear traces found in archeological basalts.