Since the first successful provenance study of Mediterranean obsidian in the early 1960s using optical emission spectroscopy, a number of other analytical techniques have been employed in this region, most commonly neutron activation analysis, x-ray fluorescence, and fission-track dating. More recently, the electron microprobe (with wavelength dispersive spectrometers) and laser ablation ICP mass spectrometry have been used to produce larger datasets of both geological source samples and archaeological artifacts. In the central Mediterranean, these research efforts have led to the identification of multiple chemical groups within individual volcanic complexes on the islands of Lipari, Pantelleria, and Sardinia, distinctions which at least in some cases may be archaeologically meaningful.

In this paper we present new data resulting from the analysis of 60 geological samples from Monte Arci, Sardinia, by NAA, XRF, and electron microprobe. Twenty-four trace elements were measured by NAA and ten by XRF; ten major/minor elements were measured by microprobe, three by NAA, and one by XRF. The results indicate that the Monte Arci source may be subdivided into at least four and possibly as many as six geographically meaningful subsources, some of which were differentially exploited during the Neolithic period depending on spatial, temporal, and other factors. Fission track dating, which does not discriminate among the Monte Arci sources, therefore produces results of only limited interpretive value. The significance of this research is demonstrated by paradigmatic shifts in obsidian provenance studies and new interpretations of obsidian exploitation in the central Mediterranean as we enter the 21st century.