“…Experimental research demonstrated that all four sources could be differentiated based on their trace element composition (Cann & Renfrew, 1964;Belluomini & Taddeucci, 1971;Hallam, Warren & Renfrew, 1976) and neutron activation analysis (NAA) or X-ray fluorescence (XRF) has been used since in many western Mediterranean obsidian provenance studies (Williams-Thorpe, Warren & Barfield, 1979;Williams-Thorpe, Warren & Courtin, 1984;Crummett & Warren, 1985;Bigazzi et al, 1986Bigazzi et al, , 1992Francaviglia & Piperno, 1987;Ammerman et al, 1990;Ammerman & Polglase, 1993, 1997Randle, Barfield & Bagolini, 1993;Crisci et al, 1994).…”