Raman Microscopy as a Primary Technique for Identifying Micro-residues Related to Tool-use on Prehistoric Stone Artefacts

Analyses of ancient micro-residues preserved on stone artefacts can potentially provide detailed information about how prehistoric humans used the artefacts to process materials such as food, pigments and/or adhesives. However, prehistoric micro-residues are likely to degrade and there are multiple potential sources of contamination, such as contact with sediments, groundwater, recent handling, storage materials or laboratory conditions, any of which can inhibit reliable identification of micro-residues and other traces of prehistoric use. In this chapter we illustrate the use of Raman spectroscopy as a primary method to identity ancient micro-residues preserved on stone artefact surfaces that are due specifically to prehistoric use as opposed to some form of ancient or modern source of contamination. Stone tools from Liang Bua (Flores, Indonesia) and Denisova Cave (Altai Mountains, Siberia) are used to demonstrate the methodology.