Laboratory Characterisation of Dalma Period Ceramics from Tepe Gheshlagh (Eastern Central Zagros, Iran)

Dalma was a pivotal culture during the 5th millennium BCE, located in the Northwest and Central Zagros regionsof Iran. Excavation at Tepe Gheshlagh, a major site in the Dalma Centre of the Talvar Valley in Bijar County,between the Eastern Central Zagros and the Southern Lake Urmia Basin, revealed a sequence of habitation thatspans the Early, Middle, and Late Chalcolithic periods. While previous research hinted at interactions between thesetwo cultural spheres, there was a lack of information regarding intermediary centres. Radiocarbon determinationsplaced the earliest settlement at Gheshlagh, characterised by the Dalma tradition, dating back to 5500‒5000 BCE.To gain a deeper understanding of the Dalma pottery manufacturing process, laboratory studies were conductedto identify the texture, constituents, and provenance of the sherds from the site. Among the assemblage, twosherds of Ubaid type were found to differ structurally from the typical local pottery, viz. Dalma Painted Ware. Asa result, XRF, XRD, and petrography techniques were applied to investigate the pottery industry and the utilisedcompounds. A total of twelve sherds were singled out for XRF / XRD analyses, while 15 others were analysedby petrography. The XRD tests identified silica, calcite, quartz, iron, aluminium, Biotite, and mica (muscovite)as the main phases present in the samples. The XRF analysis confirmed the presence of Silica, calcite, aluminium,and mica constituent elements. Furthermore, petrographic analysis detected quartz, chert, calcite, siltstone, iron,and plagioclase, which aligned with the findings from the XRF / XRD measurements. Additionally, petrographyidentified two pieces as being imports from other regions, thus pointing to the local inhabitants’ extra-regional ties.