Recognizing heat-treated chert: A comparison between infrared spectroscopy and fracture surface analysis

Heat treatment of lithic raw material is used for the first time in Europe in the Solutrean of the upper Paleolithic. The study of which heating technique was used by these groups requires analytical methods to understand and recognize the chemical and physical processes involved. Roughness measurements were tested as a tool for recognizing heat treatment and to compare them to infrared spectroscopy. We also measured the surface topography of geological samples to observe its evolution as a function of heating and then compare the results with those obtained on Solutrean artefacts. Near infrared analyses was carried out for comparing the effectiveness of surface roughness measurements. This work complements our knowledge about the heating environment used by Solutrean groups by confirming the use of controlled heating. In addition, our roughness measurements provide promising results for the recognition of heat treatment through the quantification of the surface luster.

Automated summary

This study on the heat treatment of lithic raw material in the Solutrean culture of the Upper Paleolithic in Europe utilized roughness measurements and infrared spectroscopy to understand the chemical and physical processes involved. The study confirmed the use of controlled heating and showed promising results in recognizing heat treatment through the quantification of surface luster.