Petrographic Analysis of the 6th Millennium B.C. Dalma Ceramics from Northwestern and Central Zagros

Sixth millennium BC Dalma ceramics from the northwestern and central Zagros have previously been described as being impossible to distinguish using decorative style analysis in spite of the great distance between the two regions. In this study, petrographic (thin section) analysis and a small-scale electron microprobe project was carried out on the ceramics of the two regions, as well as a small sample of the preceding and following Hajji Firuz and Pisdeli period ceramics. The petrographic analysis of microstructure reveals minute differences in manufacturing techniques. The results suggest that the Dalma ceramics were a distinct ceramic group with a great degree of variability, suggesting that they were made locally at the household level by individual potters and their preferences for ceramic manufacturing techniques. However, there was enough communication between the different regions to keep the stylistic and to a certain degree ceramic manufacturing technique uniform over this wide area. The analyses suggest that Dalma ceramics were spread by small groups of nomadic pastoralists who maintained a relationship with the agricultural Dalma villages. In this way, petrographic analysis of ceramics and geospatial analysis allow for a better understanding of the distribution of Dalma ceramics, and suggest the role of nomadic populations in their spread.