A TECHNOLOGICAL EXAMINATION OF NINTH–TENTH CENTURY AD ABBASID BLUE‐AND‐WHITE WARE FROM IRAQ,AND ITS COMPARISON WITH EIGHTH CENTURY AD CHINESE BLUE‐AND‐WHITE SANCAI WARE*

Eight sherds of ninth–tenth century ad Abbaesid blue‐and‐white glazed earthenware, excavated in 1931 at Hira in western Iraq, were analysed using, variously, quantitative wavelength‐dispersive spectrometry (WDS) and energy‐dispersive spectrometry (EDS) in association with scanning electron microscopes (SEM), and semi‐quantitative X‐ray fluorescence spectrometry (XRF). In order to compare the compositions of the cobalt pigments used, the glazes of seven complete vessels of eighth century ad Chinese Tang blue‐and‐white sancai were also analysed semi‐quantitatively using XRF. The Abbasid wares were shown to have used traditional Mesopotamian alkali–lime glazes applied to calcareous clay bodies. Half the glazes examined were opacified with tin oxide. Three types of blue decoration (i.e., raised; spreading; and flat, non‐spreading) were produced using a variety of formulations, including a mixture of cobalt pigment with lead oxide. The sources of the ores used for the cobalt pigments have not been identified. However, the analytical data showed that the cobalt ore used for the Abbasid blue‐and‐white ware could be distinguished from that used for the Tang blue‐and‐white sancai by its higher iron content and by the presence of a significant amount of zinc. The use of cobalt‐blue decoration on the ninth–tenth century ad Abbasid ware was anticipated in China by eighth century ad Tang blue‐and‐white sancai wares. However, whether its introduction by the Abbasid potters should be seen as an independent invention that followed the introduction of tin‐opacified glazes in Iraq, or whether it was influenced in some way by Chinese originals, is still unresolved.     

NEUTRON ACTIVATION PATTERNING OF ARCHAEOLOGICAL MATERIALS AT THE NATIONAL CENTER FOR SCIENTIFIC RESEARCH ‘DEMOKRITOS’: THE CASE OF BLACK‐ON‐RED NEOLITHIC POTTERY FROM MACEDONIA,GREECE

A short history of the application of NAA in the characterization of archaeological materials at the National Center for Scientific Research ‘Demokritos’, Athens, is presented. NAA was first applied in archaeology in 1974 at the Radioanalytical Laboratory, and since 1989 has been one of the primary analytical techniques of the ‘Demokritos’ archaeometry programme. A case study is also presented, concerning chemical patterning of the black‐on‐red Neolithic pottery class from Macedonia. Four chemical groups were identified, each corresponding to a different area of production. It is shown that this standardized concept of pottery technology and style was spread out within at least eastern Macedonia.     

THE IMPORTANCE OF THE ‘BEST RELATIVE FIT FACTOR’ WHEN EVALUATING ELEMENTAL CONCENTRATION DATA OF POTTERY DEMONSTRATED WITH MYCENAEAN SHERDS FROM SINDA,CYPRUS

Neutron activation analysis of pottery was established at Bonn in 1983 and has since become one of the primary archaeometry‐based analytical techniques at the facility. A brief history of the laboratory and a discussion of the best relative fit procedure for pottery is provided. When comparing concentration data for pottery, a best relative fit should always be considered. This mathematical procedure generally results in ‘sharper’ concentration patterns and improves the separability of chemically not very different compositional groups. This is demonstrated for a set of 30 Late Cypriot (Myc. IIIC1) pottery samples from Sinda, Cyprus, which allow formation of a good reference pattern for this site. Applying factors in the range of 0.82–1.43, a number of samples from Egypt and Palestine can be assigned with high probability to a Cypriot origin.     

Adhesive Production and Pottery Function During the Iron Age at the Site of Grand Aunay (Sarthe,France)*

A combination of elemental, functional and molecular analyses performed on amorphous organic residues dating from the Iron Age was developed in order to identify these remains and to understand their relationship with ceramic vessels in which some of them were found. These analyses made it possible to distinguish between ceramic vessels used for the production or storage of adhesive materials, mainly birch bark tar, and those dedicated to the preparation of culinary commodities, which contained animal fats. The organization of the production of adhesives is described and the addition of beeswax to birch bark tar is reported for the first time. The use of birch bark tar for coating ceramic vessels is also discussed.     

THE TECHNOLOGY OF PRODUCTION OF SASANIAN GLAZED POTTERY FROM VEH ARDAŠ?R (CENTRAL IRAQ)

Scanning electron microscopy coupled with an energy dispersive X‐ray detector (SEM‐EDS) has been used to study samples of Sasanian glazed pottery. Analysis of ceramic bodies revealed a general homogeneity in composition among the studied samples and the use of calcareous clay for their manufacture. Glazes are typically alkaline in composition, with sodium and potassium oxide contents between 8 and 13%, and between 3 and 5%, respectively; calcium and magnesium oxide contents are between 7 and 10%, and between 3 and 5%, respectively. These data suggest the use of plant ash together with a silica source for glaze production. Coating thickness is highly variable among different samples, from some 400 up to 1200 µm, but it is generally uniform when a single sample is concerned. Glazes are mostly coloured blue or blue‐green; copper and iron are the colouring agents detected; abundance of bubbles, silicate crystals and relics of unmelted material are responsible for their generally opaque appearance, together with the presence of weathering products. The characteristics of the body to glaze contact zone, together with the widespread presence of bubbles, would not rule out production by a single firing process. A few samples feature a peculiar gritty coating on one side of their surface; SEM images show that they are actually partially vitrified, and EDS data denote a rather heterogeneous composition. It seems possible that they result from mixing clay together with the frit used for glaze development.     

The Source Provenance of Bronze Age and Roman pottery from Cyprus

Archaeological interpretations of ancient economies have been strengthened by chemical analyses of ceramics, which provide the clearest evidence for economic activity, and comprise both the objects of exchange and its means. Pottery is often manufactured from local materials, but its compositional diversity typically prevents significant patterns of resource utilization from being identified. Centrally located and positioned on traditional shipping routes, Cyprus maintained ties with and supplied a variety of distinctive ceramic products to the major commercial centres in the eastern Mediterranean throughout Antiquity. We analysed two Cypriot .ne wares and a variety of utilitarian pottery, as well as samples of extant Cypriot clays to determine source provenance. These chemical analyses provide an objective indication of the origins of ancient (Bronze Age and Roman) ceramics manufactured on Cyprus. The distribution of the probable clay sources and the links between pottery style and the material environment also afford a perspective on the spatial organization of large‐scale pottery production on the island. Compositional analysis provides the means to assemble geographies of pottery production and to unravel the interregional system of exchange that operated in Antiquity, but the ability to accomplish these tasks is predicated on systematic analyses of ceramic products and raw materials that are found far beyond the bounds of individual archaeological sites.     

A Study Of The Firing Technique Of Pottery From Kaman‐Kalehöyük,Turkey, by Synchrotron Radiation‐Induced Fluorescence X‐Ray Absorption Near‐Edge Structure (Xanes) Analysis*

Fe K‐XANES spectra of a series of pottery sherds excavated from the archaeological site of Kaman‐Kalehöyük, Turkey, were measured to reveal the firing technique of the pottery. The analysis disclosed relationships among the chemical form of the iron, the firing conditions and the colour of the pottery. The pottery referred to as ‘Grey Ware’ found at this site was classified into two groups according to the chemical form of the iron. Also, it was revealed that the Iron Age pottery referred to as ‘Cream Ware’ was produced first under reducing conditions, and then fired under oxidizing conditions.     

Technological Features of Roman Terra Sigillata from Gallic and Italian Centres of Production

Technological features of sherds of Roman terra sigillata were studied. The sherds analysed represented products of workshops which were most probably located in Gaul, central Italy, north-west Italy and the plain of the river Po. Equivalent firing temperatures were estimated by colour measurement, X-ray diffraction and thermal expansion measurement; in addition, the chemical and morphological features of the red sintered slips were investigated using scanning electron microscopy coupled with energy dispersive X-ray microanalysis. The combined results suggest that, relative to northern Italian products,terra sigillata from Gaul and central Italy was made by potters who were more successful in modifying slip composition and controlling firing temperature to obtain highly sintered slips. Northern Italian potters seem to have worked their clays less successfully and fired them at temperatures which were too low to overcome the limited presence of fluxes in the slip.