Obsidian geochemistry

Before describing the Archaeometry Lab at MURR s involvement in research on obsidian sources and artifacts from South America, some background information on obsidian geochemistry is helpful. In addition, a description of advantages and disadvantages of various analytical methods employed to characterize obsidian is presented. 

Hughes, R.E. and Smith, R.L. (1993). Archaeology, geology and geochemistry in obsidian provenance studies. In Effects of Scale on Archaeological and Geoscientific Perspectives, ed. Stein, J.K. and Linse, A.R., Special Papers 283, Geological Society of America, Boulder, pp. 79-91. 

The study of obsidian by NAA has proved to be particularly fruitful because of the relatively limited number of sources and the extent to which it was traded (Beardsley et al. 1996, Cook 1995, Darling and Hayashida 1995, Kuzmin et al. 2002, Leach 1996). Studies have also extended to include other volcanic materials such as pumice (Bichler et al. 1997, Peltz et al. 1999). NAA has also been used for the analysis of flint as OES is insensitive and not reproducible due to the effect of the high silica content, and AAS requires significant sample preparation (Aspinall and Feather 1972). The wide range of appropriate materials extends to organic materials such as human bone (Farnum et al. 1995), and its exceptional sensitivity to trace elements has led to its wide use in geochemistry (for example in determining trace [ppb] contaminants in waters) and more recently in forensic chemistry. 

Sources of Archaeological Obsidian in Peru Descriptions and Geochemistry... 

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