EMPLOYING TL METHODS FOR THE VERIFICATION OF MACROSCOPICALLY DETERMINED HEAT ALTERATION OF FLINT ARTEFACTS FROM PALAEOLITHIC CONTEXTS

摘要

The reconstruction of past human use of fire is often based on the presence of fire in archaeological sites as evidenced by alterations of lithic material. Here, a simple test based on thermoluminescence (TL) methods is used as a verification tool for the macroscopic identification of burning damage on flint microartefacts from the Early and early Middle Pleistocene site of Gesher Benot Ya‘aqov (Israel). The small dimensions of the microartefacts often prevented the removal of the outer surface, for which the TL signal might have been altered (bleached) by exposure to light during excavation. Bleaching of the TL signal by sunlight was found for fresh raw material, but appeared to be less problematic for the archaeological material, presumably due to patination. However, TL results for some samples are ambiguous and it is sometimes difficult to distinguish heating from post-depositional bleaching, especially for samples that are macroscopically considered as not having been heated. A qualitative interpretation of the TL data is compared with the macroscopic assessment. The general agreement of the TL analyses with the macroscopic observations provides an independent verification of the observed burning and thus supports the assumption that fire was used and controlled throughout the long occupational sequence of Gesher Benot Ya‘aqov.