'Blue-' and 'Brown-speckled' pottery from Qalhat, the Sultanate of Oman (13-16th centuries): Comparison with traditional Omani 19-20 century productions

Representative 'Blue speckled' (13-16th centuries) and 'Brown speckled' (13-21st century) wares recovered from the excavations in Qalhat or collected around Bahla city (Sultanate of Oman) were characterized by XRPD, SEM-EDS, Raman/optical microspectroscopy, and thermal expansion. Minerals present in the body (quartz, augite and albite as major phases, calcite, dolomite, rutile, anatase, phosphate, hematite and magnetite as minor phases) were identified by XRPD and/or Raman spectroscopy. SEM-EDXS microanalysis was performed on the glazes in order to compare their composition, especially the type of flux. The firing temperatures measured from the thermal expansion curves range between 1080 degrees C and 1150 degrees C. This preliminary study confirms that the first differentiation can be made by considering non-invasive Raman technique and thermal expansion measurement is sufficient to get an extensive comparison of the wares. A local place of production is likely for the body of all samples but importation of the glazes of 'Blue speckled' wares is questioned. Modern Bahla productions cannot be considered to have inherited the Qalhat ones. Ba-rich, cassiteriteopacified glaze corresponding to the Late Islamic Arabic Period appears as a new technology without a connection to the ancient one. (C) 2020 SECV. Published by Elsevier Espana, S.L.U.

Automated summary

Representative 'Blue speckled' and 'Brown speckled' wares from Qalhat and Bahla in Oman were analyzed using various techniques. The study revealed differences in composition, firing temperatures, and glaze types and compositions. It is suggested that the wares were locally produced, but the origin of the glazes used in the 'Blue speckled' wares remains uncertain.