Characterization of Iranian Obsidian Artifacts by PIXE and Multivariate Statistical Analysis

It had long been thought that obsidian found in Iranian sites originated from Anatolia and Armenia, but new research has challenged this assumption. In this study, 68 samples of obsidian obtained from an archaeological survey of Nader-Tepe Aslanduz were analyzed by Proton Induced X-ray Emission (PIXE). Nader-Tepe Aslanduz is a tell site west of the city of Aslanduz in the Parsabad county of the Ardebil province in northern Iran. The site was inhabited from the first millennium B.C. to A.D. 17, and its history may extend back to the third or fourth millennium B.C. Our chemical composition results have been combined with obsidian composition data from Turkey and Armenia and subjected to Principal Component Analysis (PCA). This analysis shows that obsidian from each location can be grouped into distinctive classes—the obsidian from Nader-Tepe Aslanduz is therefore probably derived from volcanic outcrops of the Sahand and Sabalan region. This study has been unable to assign a known source from Anatolia and Armenia for the obsidian of Nader-Tepe Aslanduz.