Provenance studies, obsidian

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. 

In most obsidian provenance studies, the ability to employ compositional differences to discriminate between sources depends, to a certain extent, on the number of elements measured. Because instrumental neutron activation analysis (INAA) is capable of measuring 25-30 elements in obsidian with excellent precision, numerous combinations of trace and major elements are available for comparing differences between sources. The main requirements for success are that all sources have been located and analyzed, and that the internal variation measured within the sources be smaller than the compositional differences measured between the sources (23). 

Scorzelli, R. B., S. Petrick, A. M. Rossi, G. Poupeau, and G. Bigazzi (2001), Obsidian archeological artefacts provenance studies in the western Mediterranean basin An approach by Mossbauer spectroscopy and electron paramagnetic resonance, C. R. Acad. Sci., Series Ila, Sciences de la Terre et des Planetes, 332(12), 769-776. 

Yegingil, Z. and T. Lunel (1990), Provenance studies of obsidian artifacts determined by using fission track ages and trace element analysis, Nucl. Tracks Rad. Meas. 17(3), 433. 

Bigazzi, G., Meloni, S., Oddone, M. and Radi, G. (1986). Provenance studies of obsidian artefacts trace elements and data reduction. Journal of Radio-analytical and Nuclear Chemistry Articles 98 353-363. 

Bigazzi, G., Ercan, T., Oddone, M., Ozdogan, M. and Yegingil, Z. (1993). Application of fission track dating to archaeometry provenance studies of prehistoric obsidian artifacts. Nuclear Tracks and Radiation Measurements 22 757-762. 

Beardsley, F. R., Goles, G. G., and Ayres, W. S. (1996). Provenance studies on Easter Island obsidian an archaeological application. In Archaeological Chemistry organic, inorganic and biochemical analysis, ed. Orna, M.V., ACS Symposium Series 625, Washington, DC, American Chemical Society, pp. 47-63. 

Provenance Studies of Middle Eastern Obsidian from Sites in Highland Iran... 

The study of obsidian provenance differs from that of pottery. As compared with clays, there are a lot fewer obsidian sources hence the search for chemical matches with artifacts is much simpler. The composition of obsidian is not altered in fashioning implements, whereas potters can refine a clay in different degrees, introduce additives, or blend different clays. Experience shows that obsidian flows are more uniform in composition than are clay beds therefore, the chemical profiles are more distinctive for obsidian. 

Blackman, M. James. 1984. Provenance studies of middle eastern Obsidian from sites in highland... 

The existence of obsidian sources on the Italian islands of Sardinia, Lipari, Palmarola and Pantelleria has been well documented, and early provenance studies... 

Sixty-one obsidian artifacts from four Early Neolithic sites were selected for chemical analysis. The analysis of significant-sized assemblages from single cultural periods allows direct comparison between contemporary sites in different geographic locations. Many early provenance studies, however, relied on very few artifacts from individual sites so that such patterns in the exploitation of specific obsidian sources could not be determined (75). 

In conclusion, high-resolution provenance studies of western Mediterranean obsidian artifacts produce more detailed information on Early Neolithic exchange patterns than can studies which only attribute artifacts at the island level. This was a time when an agricultural way of life was first introduced and the Mediterranean islands were first widely settled. Obsidian, as the most visible indicator in the archaeological record of intercultural contact, is a critical material for the reconstruction of this most important transition in human prehistory. 

FIGURE 22 Obsidian in the eastern Mediterranean Sea area. Studying the relative concentration of trace elements in obsidian makes it possible to identify the obsidian and to determine its provenance. Determining the relative amounts of barium and zirconium in ancient obsidian tools and in samples from different sources of the natural glass, for example, made it possible to identify the provenance of obsidian used in eastern Mediterranean Sea area sites (Renfrew and Dixon 1976). 

There is a large and growing literature on Middle Eastern obsidian studies that contains elemental data from the analysis of many hundreds of samples. Some effort is needed to reconcile the disparate terminology used to classify sources of both known and unknown provenance. The task is made difficult by the use of different analytical techniques of varying precision, the selection of different element sets in analysis and reporting, and the use of different secondary standards to quantify the concentration data. 

This study has demonstrated that precise chemical analysis is a powerful tool for the characterization and provenance determination of Middle Eastern obsidian. Thirteen to 15 chemically distinctive groups were distinguishable in geological source samples collected from eight source... 

---