Lead Isotope Analyses of Islamic Pottery Glazes From Fustat, Egypt*

Abstract

Lead isotope analyses have been undertaken on a group of Islamic lead-glazed pottery artefacts from Fustat, Egypt, spanning the period from the eighth to the 14th century ad , that had previously been the subject of a comprehensive typological, chronological, petrographic and technological study. Comparison of the lead isotope ratios for the glazes with those for lead ores from Egypt, Iran, Tunisia, Anatolia, Greece, Sardinia and Spain provided information on the possible sources of the lead used in the production of the glazes. The results show that the lead used in glaze production by the Islamic potters at Fustat was most probably obtained from distant ore sources in Iran or Tunisia, Sardinia, Spain and the Taurus Mountains. Different ore sources were favoured in different periods and, to a limited extent, for different types of pottery, but at no time did the Fustat potters use the potentially more accessible Egyptian ore sources.

Local recipes or distant commodities? Lead isotope and chemical compositional analysis of glaze paints from the Salinas pueblos, New Mexico

“…Stacked bivariate plots facilitate comparisons between ore source groups and glaze samples (Wilson et al, 2006;Wolf et al, 2003). While some researchers (Gale and Stos-Gale, Sayre et al, 1992) recommend using discriminant function analysis to generate statistical probabilities for sample membership in ore source groups, the relatively small number of ore samples for all but the Cerrillos deposits precludes the use of this technique for our study.…”

“…Habicht-Mauche et al (2000) argue that such stockpiling and mixing of ores from different Cerrillos district mines explains the isotopic variability seen in glaze paints on pottery from Galisteo Basin pueblos. It may also explain why so many glazes have isotopic ratios intermediate between ratios for ore source groups (see also Wolf et al, 2003), plotting in areas between source clusters in Figs. 3 and 4.…”

“…Lead isotopic composition analysis has proven useful for sourcing a number of archaeological materials, including metallic leads, silver, copper, bronze, faience, glass, glazes, and other pigments (Al-Saa'd, 2000;Boni et al, 2000;Brill and Wampler, 1967;Brill et al, 1979;Gale and Stos-Gale, 1982;Stos-Gale, 1992;Wolf et al, 2003). The application of this technique to the analysis of lead-silica glazes is based on the principle that lead ores from different geological sources and the glaze paints made from them can be distinguished by ''fingerprints'' of the ratios of the four stable isotopes ( 204 Pb, 206 Pb, 207 Pb and 208 Pb).…”

The use of oxygen, strontium and lead isotopes to provenance ancient glasses in the Middle East

“…A much larger number of lead isotope determinations taken from artifacts from a relatively small area has underlined the complexities of recycling and other parameters in attempting to source metal used in artifacts [20]. No such study has yet been attempted for glasses, though recent determinations of lead isotopes in Islamic glazes from Fustat, Egypt provide a hint as to the potential complexity of lead use in the Islamic world, including an indication that the lead used travelled over considerable distances [28]. The low levels of lead impurities found in some ancient glasses may have derived from glass recycling [12, p. 70].…”

“…This data suggests that the d 18 O of archaeological glass is dependent on the predominant SiO 2 although it must be acknowledged that there maybe other oxides present (Table 3). Natron Aqua window glass, lustre decoration, thin weathering layer Raqqa 33-34 (P, C, Q) [15] Plant ash Purple (P) and colourless (C), quartz (Q) fragment attached; raw glass Raqqa 45/46 [21] Plant ash Green, well preserved, raw glass Raqqa 50 [27] Plant ash Pale green base fragment, thick weathering Raqqa 54 [28] Plant The plant ash glasses have generally lower d 18 O values than natron glasses, although this is only marginally above experimental error. The glass sample which was subdivided into two sub-samples based on colour (the colourless Raqqa 33-34C and the purple Raqqa 33-34P) gave d 18 O values within error as might be expected.…”