Heat Treatment of Chert in the Early Mesolithic at Rottenburg-Siebenlinden (Southwest Germany)

Abstract

ABSTRACT Unambiguous evidence for heat treatment in the Early Mesolithic of Southwestern Germany is thus far restricted to one type of raw material and to cave sites of the Swabian Jura region. At the open-air site Rottenburg-Siebenlinden, heat treatment of an additional raw material was proposed. In this paper, we reexamine the lithic assemblage of horizon III, using the best available criterion for recognizing heat treatment: gloss contrast. Through technological analysis of these diagnostic artefacts, we investigate the timing of heat treatment within the reduction sequence. Visual identifications were substantiated by analyzing surface roughness of gloss contrast artefacts. Our results show that heat treatment was regularly applied to a wider range of raw materials than previously thought, during blank production. These findings highlight that the last Central European hunter-gatherers were flexible in terms of material choices and that heat treatment was a more widespread phenomenon than previously thought.