The First Obsidian Source in North-Western Iran for Provenance of Local Prehistoric Lithic Artifacts

Obsidian is a dark glass formed by very rapid solidification of volcanic lava, but in the archaeological view, this volcanic glass is an important source for prehistoric tool-making and artifacts such as arrowhead, point, flake, blade, hand axes, micro-blades and etc. Therefore, obsidian artifacts are frequently used material in prehistory and found widely in archaeological sites around the world. The provenance study of obsidian has been an issue of intense research and debate between archeaometrist and geologists. Hence, different provenance studies carried out in Anatolia and Caucasus since 1960s up to 2015, but the obsidian research in Iran is in very early stage and consider as terra incognita. According to the occurrence of lithic obsidian artifacts in most of the prehistoric archaeological sites in north-west of Iran have been recovered during last decades, various questions have been rise on the subject of the provenance of these materials. New studies on prehistoric obsidian artifacts have been done by other scholar specially Iranians during the recent years, where the main part of these studies focus on the characterization and classification of the obsidian artifacts by chemical analysis, in order to find an evidence of sourcing and provenance. More recent research showed that some obsidian tools might have come from unknown sources located in Iran (perhaps Sahand and Sabalan Mountain). This paper will try to discuss the new obsidian mine in north-west Iran in western Asia. After a brief introduction of obsidian studies in north-west Iran, the paper addresses preliminary report of recent researches that took place concerning 10 local obsidian mine samples from Tajaraq of Miyaneh and Ghizilja of Bostababad, around of Bozghoosh Mountain in the skirt of Sahand volcano. This study was realized by portable X-ray fluorescence (pXRF), as a non-distractive technique for elemental analysis, to differentiate between local obsidian mine. From 10 mine samples, 8 samples from Tajaraq of Miyaneh and 2 samples of Ghizilja of Bostanabad were selected and analyzed. This mine samples could be consider as the first obsidian source specimens in association with prehistoric lithic artifacts of north-west Iran and give the chance for detail and comparative studies of these sources with prehistoric site artifacts for provenance studies, as local or imported materials to this part of Iran. The research has been carried out with a focus on locating the origins and resources of obsidian procurement in the northwest of Iran, in order to rethink and reconstruct the regional and supra-regional trade and exchange networks in future. The project clearly identified the three groups of geochemically different obsidians named Tajaraq A, Tajaraq B, and Ghizilja. Due to the fact that Tajaraq obsidian is of a higher quality than the Ghizilja ones, it seems likely that the samples of Tajaraq obsidians have had the ability to be used for tool-making in the past, as the samples of Ghizilja, Bostanabad are too fragile and perlitic in structure. Hence, as the two groups of Tajaraq A and Tajaraq B have the ability to be used for ancient tools in all probability, they can be introduced as candidates for obsidian mining in prehistoric times in the northwest of Iran. In fact, the proposed hypothesis is still at a very early stage and future scientific studies and field research have to be followed. Comparing the new results with prehistoric sites in the cultural areas of Miyaneh and Bostanabad, it becomes obvious that the Tajaraq B obsidian overlaps in some trace elements with published data Anatolian sources. If this overlap could be found also by comparing other elements and their combination, and if it will be confirmed by other methods in future, it could lead to a complete review of all previous obsidian analysis from Iran. In other words, several samples that were up to now thought to be from Anatolia could come in reality from source B of Tajaraq. This is a serious and peculiar hypothesis, which means, at first step, more data have to be collected at the geological outcrops and especially, by analyzing the archaeological finds from well stratified context. The implications of the findings will discuss along with limitations and future research directions.