Black-Coloured Bones in Hayonim Cave, Israel: Differentiating Between Burning and Oxide Staining

Identification of fossil burned bones is commonly based on their black colour. While colour-based identification is applicable to recent burned bones, fossil bones may be black due to mineral staining, such as by black manganese oxides. We therefore developed an analytical method that purifies oxides from bones. The end product of the method was analysed by means of Fourier transform infra-red (FTIR) spectroscopy. The method can be used for differentiating between black fossil bones that are burned and unstained, burned and stained, and stained but not burned. A survey of 30 black bones from the Mousterian and Aurignacian deposits of Hayonim Cave (Israel) showed that the majority of the bones were indeed burned, of which a few were burned and stained. Several bones were stained and unburned. This method can be readily applied to other archaeological sites where the proportions of burned and stained bones may be quite different.