ESR signal behavior study at g∼2.002 of modern and fossil bones for heating palaeotemperature assessment

A modern red deer bone was heated in a muffle furnace at increasing temperatures in the range 200 to 940 deg. C. Samples were analyzed by infrared and X-ray diffraction spectrometry before measurement of the ESR signals around g=2.002 by ESR spectrometry. Each sample was irradiated by a gamma source (cobalt-60) at increasing doses in the range 100 to 10 000 Gy. γ-irradiated samples were then analyzed by ESR spectrometry in order to obtain the growth curve and to show ESR signal behavior. ESR signals of fossil bones from archaeological deposits of the Lazaret cave (Middle Pleistocene, France) were studied and colors were compared with modern samples in order to assess at which temperature these fossil bones were heated in prehistoric fireplaces