Variability in pottery production at Khalet al-Jam'a necropolis, Bethlehem (West Bank). From the Early-Middle Bronze to the Iron Age

Rescue excavations undertaken by Sapienza University of Rome and the Palestinian Ministry of Tourism and Antiquities, Department of Archaeology and Cultural Heritage (MOTA-DACH) revealed a huge necropolis in the site of Khalet al-Jam'a, south-east of Bethlehem. Tombs were used during the Early Bronze IV (2300–2000 BCE) to Middle Bronze I–III (2000–1500 BCE) periods, and up to the Iron Age IB–II (1050–700 BCE). This paper presents the results of the minero-petrographic and chemical characterization of ceramic material from this site, with the aim to reconstruct the technological level achieved by ancient populations living in Bethlehem from the Early Bronze IV to the Iron Age by means of optical microscopy, X-ray Powder Diffraction, Scanning Electron Microscopy with Energy Dispersive Spectroscopy and Thermogravimetric Analysis. Results show that two main supplies of raw materials can be recognized at Khalet al-Jam'a. The Early and Middle Bronze Age ceramic production is made with the so-called Moza-clay: a calcareous-rich clay with predominant limestone, diffuse grains of calcite, dolomite, and rare sedimentary siliceous rock fragments, quartz and microfossils. The latest production, namely that of the Iron Age, is more likely consistent with the calcareous-foraminiferous-Rendzina soil clay, with predominant silty quartz and few microfossils. The firing temperature was estimated from the mineralogical assemblage in each sample. Abundant calcite, clay minerals and the absence of neo-formed minerals suggest samples fired at temperatures lower than 800 °C. For those samples where calcite was found along with gehlenite and wollastonite, the temperature was indeed estimated to be in the range 850–950 °C. Finally, the firing atmosphere was uncontrolled, as testified by the extreme variability in colour of the matrix. The results of this study enable a preliminary characterization of pottery, whose production shows differences related to specific historical periods and contribute to improve the knowledge about specific ceramic production used in funerary contexts.