Unglazed pottery from the masjed-i jom’e of Isfahan (Iran): technology and provenance

Abstract

The masjed-i jom’e of Isfahan is one of the earliest mosques of Iran. Since 1970, Italian researchers performed an extensive archaeological investigation uncovering huge amounts of finds. This study aims at investigating the technological features and provenance of the unglazed pottery finds by using a minero-petrographic approach. Twenty-three samples of storage, table and cooking wares were selected based on the recurrence of typologically identifiable fragments and fabrics. Two bricks, seven production indicators (spacers, kiln furniture, slags) and a local clay were analysed for comparison. The production indicators and most of the pottery show high-CaO concentration. Thick-walled wares contain coarse sedimentary/metamorphic inclusions. Samples with thinner walls contain similar but fine/well-sorted inclusions. The mineralogy and microstructure indicate firing temperatures mainly ranging from 850 to 1000 °C. Low-CaO samples contain coarse sedimentary inclusions; in one sample, volcanic lithics are present. Firing temperatures range from about 800 to 950 °C, and the low-CaO character can be related to their specific function for cooking foods. One sample, found in older stratigraphic levels, differs for its peculiar calcitic temper and lower firing temperature. Local production of most samples was constrained by the composition of the inclusions compatible with the sediments of the Isfahan area. High-CaO pottery shows compositional affinity with production indicators, local clay and tiles produced in Isfahan during the Safavid period. Cooking ware usually contains local temper, with the exception of a sample with volcanic inclusions, for which a non-local provenance is supposed. No appropriate information is, however, available regarding the low-CaO clays used in the area.