NEW ARCHAEOMAGNETIC STUDIES NEAR XI'AN,CHINA*

Archaeomagnetic and mineral magnetic studies were made of known-age samples from fired structures and sediments from archaeological sites near Xi'an, China. The fired materials retained a stable record of the direction of the past geomagnetic field, which compared well with previous investigations and could contribute to an archaeomagnetic calibration curve. However, discrepancies with documented observations of the field were noted.     

LEAD ISOTOPE ANALYSIS OF TANG SANCAI POTTERY GLAZES FROM GONGYI KILN,HENAN PROVINCE AND HUANGBAO KILN,SHAANXI PROVINCE

Through the use of MC–ICP–MS, this study analyses the lead isotope ratios of 19 Tang Sancai pottery glazes unearthed from the Gongyi and Huangbao kiln sites. According to their different lead isotope ratios, the two kilns can be grouped separately. The research also suggests that the Gongyi and Huangbao kilns are independent production centres of Tang Sancai in the Tang Dynasty. The data from the Huangbao kiln indicates that the lead in the glazes originates from the Northern China geochemical province, while the data from Gongyi kiln suggests its source as the Yangtze geochemical province. Furthermore, the results obtained for the Tang Sancai pottery indicate that the lead sources for glaze making of these two kilns were very consistent, which suggests that lead isotope analysis could be a helpful method to identify the kilns producing Tang Sancai artefacts.     

AN ARCHAEOMAGNETIC STUDY OF POTTERY KILNS FROM BRÜHL-PINGSDORF (GERMANY)*

Four pottery kilns from Brühl-Pingsdorf (Germany) were dated by comparing their characteristic remanent magnetization with a curve of the palaeo-secular variation of the geomagnetic field. Archaeomagnetic results suggest last heating events between AD 775 and 1020. The archaeological evidence generally supports the relative temporal succession and the duration of use, but indicates that the kilns are about 150 years younger on average. Hence, a systematic offset between these independently developed chronologies must be considered. Rock magnetic parameters display radial variations through the kiln walls. These variations are controlled by the maximum temperature the rock was exposed to. These parameters were used to identify specimen which acquired a thermoremanent magnetization.     

NEUTRON ACTIVATION ANALYSIS OF ROMAN AFRICAN RED SLIP WARE KILNS

Roman African Red Slip ware (ARS) sherds from four ARS kiln sites in modern-day Tunisia (El Mahrine, El Ala, Oudna and Pheradi Maius) have been analysed using instrumental neutron activation analysis. Multivariate statistical methods (including cluster analysis and Manhattan City Block distances), with a dilution correction applied to the data, were used to interpret the concentration data. Reference groups for each of the four kiln sites were established. Both El Mahrine and Oudna were described by two dilution-related groups. These kiln groups were all shown to be compositionally distinct from each other and suitable for use in provenance studies.     

STUDY ON THE PROVENANCE OF XICUN QINGBAI WARES FROM THE NORTHERN SONG DYNASTY OF CHINA

The Xicun kiln in Guangdong Province was a famous porcelain kiln in the Song Dynasty of China, and for years there has been controversy over the provenance of Xixun Qingbai wares. This paper analyses Qingbai samples from the Xicun, Hutian (Jingdezhen) and Chaozhou (Guangdong Province) kilns by laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) and energy‐dispersive X‐ray fluorescence probe (EDXRF). The analytical results indicate that wares with a thin body excavated from the Xicun kiln site were produced in the Hutian kiln, and wares with a thick body were locally fired in Xicun; the contents of trace elements (V, Rb, Ba, Ta, Pb and Th) and the Nb/Ta ratio can be used to discriminate the products from the Xicun and Chaozhou kilns.     

BYZANTINE CERAMIC PRODUCTION FROM CUMA (CAMPI FLEGREI,NAPOLI)*

Samples of table and cooking ware, dating back to the Byzantine period of the ancient Greek colony of Cuma, were analysed by optical microscopy, X‐ray diffraction, X‐ray fluorescence and scanning electron microscopy, in order to reconstruct the main technological properties of these manufactures. The comparison of minero‐petrographical data from these samples with those of some kiln wastes allowed us to hypothesize a local manufacture for most of the investigated specimens and to confirm the relative reference groups. A restricted number of samples did not link with the main groups, indicating a regional (or maybe extra‐regional) production, in agreement with the widespread circulation of this high‐medieval ceramic production in southern Italy.     

PETROGRAPHIC AND CHEMICAL CHARACTERIZATION OF POTTERY PRODUCTION OF THE LATE MINOAN I KILN AT HAGHIA TRIADA,CRETE*

Pottery from the Late Minoan I kiln at Haghia Triada in the Mesara Plain, southern Crete, was analysed by a range of techniques, comprising thin‐section petrography, scanning electron microscopy, X‐ray diffraction, X‐ray fluorescence and neutron activation analysis. The project characterizes the ceramic fabrics and probable raw materials, correlates paste recipes with shape, reconstructs the firing conditions of the kiln and establishes a chemical reference group, taking into account post‐burial alteration and contamination. Comparison of the reference group formed with that from the neighbouring, broadly contemporary, kiln at Kommos shows an unexpected differentiation of the two kilns.     

THE CHEMICAL COMPOSITION OF BLUE PIGMENT ON CHINESE BLUE‐AND‐WHITE PORCELAIN OF THE YUAN AND MING DYNASTIES (ad 1271–1644)*

The chemical compositions of the glazes and pigments of 39 blue‐and‐white porcelains of Ming Dynasty date and three of Yuan date were examined by SR‐XRF. Both the analysis of the Fe/Mn ratio in the light blue areas of the glaze and a comparison of the Fe/Mn values between light blue, dark blue and clear glaze areas reveals that the samples can be divided into three groups. The results indicate that there are two significant changes of provenance of blue pigment during the Ming Dynasty and that some kinds of pigment were most probably imported from the Middle East. Considering literature records and other scholars’ studies, an outline picture of the pigment used on Chinese blue‐and‐white porcelain produced in Jingdezhen in the Yuan and Ming Dynasties is presented.     

WHY A KILN? FIRING TECHNOLOGY IN THE SIERRA DE LOS TUXTLAS,VERACRUZ (MEXICO)*

The benefits of one ceramic firing technology over another are not absolute, but depend upon the interaction of multiple environmental, economic and social factors, as well as the specific design of firing facilities. The coexistence of updraft kilns and open firing methods in the Sierra de los Tuxtlas, Veracruz, Mexico, for over 1700 years provides a case‐in‐point. Evaluation of the performance characteristics of ancient and modern firing technologies in relation to their natural and behavioural contexts offers a more secure basis for understanding this specific historical instance of long‐term polymorphism than explanations based in the generalized technological advantages of kilns or their cross‐cultural association with intensive modes of production.     

RESEARCH REPORT: MAGNETIC INVESTIGATIONS AND THE AGE OF A MEDIEVAL KILN AT KUNGAHÄLLA (SOUTH‐WEST SWEDEN)*

The results from a magnetic survey and archaeomagnetic investigation of a medieval brick kiln at Kungahälla in Bohuslän (south‐west Sweden) are reported. Detailed magnetic total field and magnetic gradient measurements over known traces of the kiln showed marked local magnetic anomalies of up to 200 nT, revealing the rectangular shape of the kiln remains. Palaeomagnetic investigations of the remanent magnetization of 12 bricks from the kiln floor gave precise definitions of both the direction of the archaeomagnetic field [(D_m, I_m) = (66.7°, 8.8°), k = 655, α₉₅= 1.7°] and the palaeointensity [B_m= 69.0 ± 3.6 µT]. An archaeomagnetic date is obtained by comparing the direction of the archaeomagnetic field found in the kiln with a geocentral dipole‐transformation of the British master‐curve for secular variation. Of two possible archaeomagnetic dates (ad 1280 ± 50 or ad 1480 ± 50), the ad 1280 ± 50 age is in good accordance with the C‐14 ages and archaeological dates as well as with direct historical evidence, whereas a c. 100 years younger TL date appears to be too young.