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

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.

KEYWORDS:

• Mesolithic
• heat treatment
• chaîne opératoire
• Tempern
• Muschelkalkhornstein
• Beuronian

Acknowledgements

We thank T. Beutelspacher for providing insights into the fieldwork and the analysis of the lithic assemblage studied herein, reviewing the manuscript, and the sorting into raw material units by him and C.-J. Kind. We thank H. Floss and M. Siegeris for helping with the acquisition of reference samples, K.G. Nickel for providing access to the muffle furnace used, E. Moos for knapping the experimental material and D. Huber for assisting with the layout of Figure 6. We also thank C. Berthold of Tübingen University’s CCA-BW for providing access to the laser-scanning microscope used in this study, as well as N. J. Conard for providing a workspace at Castle Hohentübingen for the duration of the analyses.

Figure 6. Mean surface roughness in μm. RMUs are noted for artefacts for which more than one per RMU was measured.

Disclosure Statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

PS received funding from the Deutsche Forschungsgemeinschaft (DFG) (grant number SCHM 3275/3-1).