DETERMINING POTTERY PROVENANCE: APPLICATION OF A NEW HIGH-PRECISION X-RAY FLUORESCENCE METHOD AND COMPARISON WITH INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS*

A recently developed high-precision X-ray fluorescence (XRF) method, applied for the first time to the study of archaeological pottery, determines the abundances of 13 trace and four major elements from one X-ray spectrum acquired over a 1000 second counting interval. For replicate archaeological samples, the short-term and long-term measurement precisions were close to 1% for the ten elements measured with highest precision. These are comparable to the best results achieved on replicates of clay and pottery standards, and obsidian, using instrumental neutron activation analysis (INAA). High-precision XRF analysis, however, does not require a nuclear facility, and is markedly preferable to INAA in terms of the ease of both sample preparation and analytical procedure. Consequently, element abundance data can usually be provided by a single analyst within a few hours after the start of sample preparation. The accuracy of the method, determined by comparison with data of other workers on eight standard reference materials, averaged 2.4% for the ten best-agreeing elements. The effectiveness of the method for determining pottery provenance is demonstrated for a difficult problem, in which high-precision XRF analysis successfully distinguished the products of two nearby pottery manufacturers in Roman Galilee (Shikhin and Nahif) that had not been clearly differentiated by INAA. The greater effectiveness of high-precision XRF than INAA in this provenance study is a result of the different array of elements measured, and the higher precision obtained for certain elements, by XRF. These results suggest that high precision XRF has potential broad applicability for pottery provenance studies.     

LEAD ISOTOPE AND TRACE ELEMENT ANALYSIS IN THE STUDY OF OVER A HUNDRED SOUTH INDIAN METAL ICONS*

Technical investigations were made on 130 South Indian statuary images and a few miscellaneous artefacts mostly sampled from the Government Museum, Madras, India, and from the Victoria and Albert Museum and the British Museum, UK. Lead isotope investigations were attempted on 60 of these, and compositional analysis for 18 elements on 115, using inductively coupled plasma optical emission spectroscopy; thus, for 40 objects both lead isotope and trace element analysis was done. From the isotopic and elemental framework, insights are obtained into some art-historical problems of images and artefacts of the Pre-Pallava, Pallava, Chola (i.e., Vijayalaya Chola), Later Chola (i.e., Chalukya-Chola and Later Pandya), Vijayanagara (and Early Nayaka) and Later Nayaka (and Maratha) dynasties, spanning the Early Christian era to the nineteenth century, along with a few other regional styles. Inferences are also made regarding provenance of the lead and the early use of zinc and brass in the early historic period (c. fourth century BC—fourth century AD).     

A QUANTITATIVE FABRIC ANALYSIS APPROACH TO THE DISCRIMINATION OF WHITE MARBLES*

Quantitative fabric analysis was applied in order to discriminate better among white marbles from various quarries of archaeological interest. This method provides an effective complementary tool to a characterization based upon petrography, cathodoluminescence microscopy and stable isotopes. Very good discrimination of marbles is achieved with the help of simple variables such as major axis and the shape-specific PARlS-factor. Using quantitative fabric analysis, marbles with similar cathodomicrofacies, as, for example, the Naxian quarries of Apiranthos, Koronos, Flerio and Kinidaros and the quarry of St. Beat (French Pyrenees), can be distinguished from each other. Marbles collected within one quarry may display dissimilar cathodomicrofacies. The common origin of such specimens can be determined with the aid of quantitative fabric analysis, as shown for the quarries of Kinidaros as well as St. Béat.     

A NEW METHOD FOR THE DETERMINATION OF THE PROVENANCE OF WHITE MARBLES BY CHEMICAL ANALYSIS OF INCLUSION FLUIDS: THE MARBLES OF THE MAUSOLEUM OF BELEVI/TURKEY*

A new method is presented in this paper to pinpoint the origin of white marbles using the chemical analysis of fluids occurring as micro-inclusions in calcitic or dolomitic marbles. Beside the conventional methods usually applied for this purpose, the analyses of significant anions and cations in fluids extracted from white marbles were used to characterize different types of marbles. Using this new approach it is possible to distinguish different groups of marbles which cannot be separated isotopically. A case study was performed on the mausoleum of Belevi, close to Ephesus in Turkey, and the quarries in the area of the mausoleum. The marbles used for the architecture of the mausoleum cannot be distinguished isotopically but were split into two groups when using fluid inclusion analysis. The corresponding quarry for the high-quality marble (cella walls, columns etc.) turned out to be the Kentli Çiftliği quarry, which also supplied the marbles for the classical Artemision. According to the chemical and fluid data it can be shown, however, that neither the adjacent famous antique quarry of Belevi nor the underground mine of Kusini, some 5 km away from the mausoleum, are the sources for the marbles used for the construction or decoration of the mausoleum.     

Chemical Variability in Clays and Pottery from a Traditional Cooking Pot Production Village: Testing Assumptions in Pereruela*

This paper explores analytically the contemporary pottery‐making community of Pereruela (north‐west Spain) that produces cooking pots from a mixture of red clay and kaolin. Analyses by different techniques (XRF, NAA, XRD, SEM and petrography) showed an extremely high variability for cooking ware pottery produced in a single production centre, by the same technology and using local clays. The main source of chemical variation is related to the use of different red clays and the presence of non‐normally distributed inclusions of monazite. These two factors induce a high chemical variability, not only in the output of a single production centre, but even in the paste of a single pot, to an extent to which chemical compositions from one ‘workshop’, or even one ‘pot’, could be classified as having different provenances. The implications for the chemical characterization and for provenance studies of archaeological ceramics are addressed.     

NEUTRON ACTIVATION ANALYSIS OF BIRD BOWLS AND RELATED ARCHAIC CERAMICS FROM MILETUS

In this paper we present the results of a chemical investigation by neutron activation analysis of sherds of different kinds of bird kotylai, bird bowls and related wares excavated in Kalabaktepe, a hill of the ancient city of Miletus. A new archaeological classification of this well-known group of Archaic ceramics of eastern Greece is presented. A number of kiln wasters of misfired vessels from Kalabaktepe revealed a characteristic local pattern. This pattern helped to clarify the provenance of some of the bird bowls classified archaeologically as of orientalizing type: they have been made in Miletus. But bird kotylai and bird bowls in the 'standard fabric’as well as other archaeologically related vessels show a different chemical pattern of unknown provenance.     

Post‐Depositional Elemental Alterations in Pottery: Neutron Activation Analyses of Surface and Core Samples*

From 38 sherds with ‘corroded’ surfaces, two samples per sherd were examined using Neutron Activation Analysis, one from the surface and one from the core of each sherd, in order to analyse post‐depositional alterations of minor and trace elements. The most striking effect was that a leaching of Ca could be found at the surface. Another group of elements that is severely affected are the alkali metals, with Cs and Rb showing the strongest changes. A third conspicuous group of elements are the Rare Earth Elements. Finally, the effect of such alterations on a statistical data evaluation to classify pottery according to provenance is investigated.     

Inductively coupled plasma emission spectroscopy and Postclassic Petén slipped pottery: an examination of pottery wares,social identity and trade*

ICP–ES analysis of the clay pastes of Postclassic (c. ad 850–1524) slipped pottery from the central Petén lakes region establishes chemical composition groups that provide information concerning manufacturing traditions and trading patterns. These data demonstrate that manufacturing traditions and trading patterns change throughout the Postclassic period, reflecting possible socio‐political alliances as different ethnic groups migrated to and from the Yucatán peninsula into the central Petén lakes region. The chemical composition groups also demonstrate that some manufacturing traditions imitate those from the Late Classic period and that some clay sources were used throughout the Postclassic period for multiple ceramic groups.     

INVESTIGATION ON ROMAN LEAD GLAZE FROM CANOSA: RESULTS OF CHEMICAL ANALYSES*

Five sherds of green glazed pottery excavated at Canosa (Apulia) in Italy have been analysed by scanning electron microscopy. The aim of the investigation was to determine the chemical composition of the glazes and thus obtain information on the methods used in their production. The glazes were all of the high‐lead type, coloured green by the addition of copper. Intermediate layers, observed at the interface between the glaze and body and giving the appearance of an applied white slip, were the result of the crystallization of lead feldspar from the molten glaze. Non‐calcareous clays were used in the production of the pottery bodies. Concentration profiles from the glaze exterior to the body suggested that the glazes were produced by applying a suspension consisting of lead oxide plus silica to the bodies. On the basis of the glaze and body compositions, it is suggested that the Canosa glazed pottery was produced locally.     

LASER ARGON DATING AND GEOLOGICAL PROVENANCING OF A STONE AXE FROM THE STONEHENGE ENVIRONS*

The recently-developed laser microprobe ⁴⁰argon-³⁹ argon technique has been used to give a geological date for a rhyolitic tuff stone axe fragment from the Stonehenge environs. The method requires only milligramme-sized samples and gives dates of sufficient accuracy to aid in provenancing artefacts to sources, as well as information on the heating history of samples. The axe sample is of Lower Carboniferous date (341 ± 5 Ma) and this limits possible sources to outcrops within the Scottish Midland Valley and small altered exposures in Dartmoor. X-ray fluorescence analysis of the axe suggests the Scottish Midland Valley as the more likely source. The laser argon analysis also shows that the implement had not been heated in antiquity. Laser argon-argon dating can, therefore, be a useful tool in artefact study.