Medieval glazed pottery from sites in Iran, Afghanistan, and India were analyzed by neutron activation analysis. In addition, a secondary clay standard and some samples were analyzed by x-ray fluorescence for their main components. The results of the trace analysis formed the basis for cluster analysis using the min. spanning tree graph theor. method The samples were partitioned into 5 clusters, which were compared with the provenance of their respective members. Preliminary results indicated that pottery from the north of Afghanistan could be differentiated from the southern kind, whereas the southern ware seemed to be homo-geneous over a large area from Herat to Ghazni. Some of the pottery samples from Sistan had a different composition due to a different production technique. The mass probably con-sisted of a 4:1 mixture of quartz and clay or a 15: 4:1 mixture of quartz, clay, and frit for the glaze. A similar recipe was described by Abu'l-Quasim, a medieval Persian potter. -- AATA