MULTI‐METHOD MARBLE PROVENANCE DETERMINATIONS: THE CARRARA MARBLES AS A CASE STUDY FOR THE COMBINED USE OF ISOTOPIC,ELECTRON SPIN RESONANCE AND PETROGRAPHIC DATA*

A multi‐method approach, based on petrography, stable isotope data and electron spin resonance spectroscopy for assigning the provenance of white marbles, is presented. A total of 11 experimental variables has been used, including the quantitative measurement of the sample colour and its homogeneity. On this basis we attempt to distinguish the three main quarrying basins of the Carrara district, that is, Torano, Miseglia and Colonnata. Such discrimination, extremely uncertain on the basis of the single techniques, may be performed with acceptable confidence’ using a properly selected subset of six petrographic, isotopic and spectroscopic variables. The final resubstitution and jackknifed re‐assignment rates are, respectively, 85% and 81%. Inclusion of the remaining five variables into the classification rule does not improve the results, but simply increases data overinterpretation. The practical possibility of using such an approach for more general provenancing problems is considered.     

CYPRIOT BYZANTINE GLAZED POTTERY: A STUDY OF THE PAPHOS WORKSHOPS

Twenty‐five samples of Byzantine glazed pottery from two archaeological sites between Limassol and Paphos region (Cyprus), dated between the 12th and 15th century ad were studied using micro X‐ray fluorescence spectroscopy, scanning electron microscopy and X‐ray diffraction analysis. It was found that all the glazes contain lead, following the main manufacturing process of medieval pottery in the Mediterranean territory, while some of them contain tin, possibly for better opacity. Furthermore, it is shown that copper, iron and cobalt with nickel are responsible for the decoration colours. Finally, the application of principal component analysis revealed significant differentiation for some of the samples.     

THE OPAQUE RED GLASS OF CELTIC ENAMELS FROM CONTINENTAL EUROPE

Opaque red glass was used in the Celtic world for enamels and inlays. Forty artefacts, of various dates and found in various places, have been sampled and studied. They all belong to the same type, a soda-lime-silica high lead glass coloured by crystals of cuprous oxide. There is only one subgroup: glass lumps from the Mont-Beuvray oppidum contain manganese, less iron, and less lead. This change could be the result of Roman influence. Although most of these glasses form a surprisingly homogeneous group, no conclusions as to their origin can be inferred from our present knowledge.     

A SCULPTURAL MARBLE OF PRIME QUALITY IN ANTIQUITY—THE DOLOMITIC MARBLE OF THE SIVEC MOUNTAINS IN MACEDONIA

This paper presents analytical data on a major occurrence of fine‐grained dolomitic marble in the Sivec Mountains, close to the city of Prilep in today's former Yugoslavian Republic of Macedonia. This is the first presentation of an analytical database of a large‐scale source of fine‐grained dolomitic marble, whose ancient use can be demonstrated by tool marks and archaeological evidence. Many traces of ancient mining have fallen victim to a big modern quarrying operation in this area, which for decades has produced high‐quality blocks of marble (‘Macedonian Carrara’) and exported them all over the world. A combination of different analytical methods is used to characterize the marbles and to present a database for investigating ancient artefacts made of fine‐grained dolomites. Petrographic investigations revealed the very homogeneous micro‐fabric of this marble, which is of high purity with very low silicate contamination and has a maximum grain‐size of 1 mm. In addition to analysis of the stable isotopes, trace element analyses of carbonate lattice elements (Mg, Fe, Mn and Sr) were performed. An alternative method, the analysis of the chemical composition of the inclusion fluids, was also employed. On the basis of these techniques, a multivariate discrimination analysis was performed, and a clear separation of the different dolomitic marbles (Thasos, Ephesos, Proconnesos and Karacasu) was obtained. Finds of artefacts of high artistic quality made from this dolomite prove the existence of a significant workshop in the neighbourhood of the Sivec quarries. Because of its vulnerability to weathering, this fine‐grained dolomitic marble was used preferentially for indoor applications. Sculptures of prime artistic quality made of Sivec marble have so far been found in several locations of the Republic of Macedonia.     

THE ESTABLISHMENT OF A DATA BASE OF NEUTRON ACTIVATION ANALYSES OF WHITE MARBLE*

The establishment of a data base of trace element analysis results obtained by neutron activation analysis of 183 marble samples, each weighing about 200 mg, from eight different quarrying localities for use in provenance studies is described and a summary of the results presented. The problems of sampling museum artefacts are discussed, and details of tests of the reproducibility of the technique are given together with those obtained from multiple-samples from single museum objects. Replicate analyses of a marble standard are also discussed. Thus these data are a measure of the accuracy and precision of the technique, as well as allowing an assessment of the variation in trace element composition within quarry sources and single blocks of marble, as used for artefacts.     

AN ANALYSIS OF THE GEM‐BLUE GLAZE OF YE WANG'S KOJI POTTERY*

Koji pottery is a glazed ceramic art used widely for figurines. In early Taiwan, it was employed in temple construction for decorative purposes. Ye Wang (1826–87) is the first historically documented Koji artist of Taiwan and also the most prominent Koji pottery artist, noted for his modelling and glazing skills. Unfortunately, his unique technique was lost following his death in 1887. In order to provide vital information for ongoing conservation work on Koji pottery, this study analysed the physical and chemical characteristics of Ye Wang's gem‐blue glaze, to discover the glaze formula. DSC combined with the two‐thirds rule revealed that the firing temperature of Ye Wang's works of art was most probably around 878–923°C. EPMA revealed that the gem‐blue glaze has high alkali levels, and belongs to the PbO–K₂O–B₂O₃–Na₂O–SiO₂ system, deriving its unique colour from copper, iron, manganese and cobalt. This study found high potassium levels in the gem‐blue glaze, which are generally a characteristic of traditional Chinese glazes. In addition, a unique discovery of boron, commonly used in famille rose, was also identified in the glaze. By comparing spectra of historical and reconstructed glazes and adjusting the proportion of chromophoric elements, this study found a glazing formula with colours close to those of Ye Wang's gem‐blue glaze.     

A SCIENTIFIC INVESTIGATION ON THE PROVENANCE AND TECHNOLOGY OF A BLACK‐FIGURE AMPHORA ATTRIBUTED TO THE PRIAM GROUP*

The restoration of a Greek black‐figure amphora provided an opportunity to study the provenance and production technology of the vase. The composition of the ceramic body, determined by inductively coupled plasma optical emission spectroscopy (ICP–OES), matches that of Attic products. Investigation by X‐ray diffraction and reflectance spectroscopy suggests a maximum firing temperature around 900°C and a body re‐oxidation temperature around 800°C, respectively. The morphology and composition of black, red and dark red surface areas were studied by scanning electron microscopy and X‐ray energy‐dispersive analysis; the black areas show the features of a typical well‐vitrified black gloss, while the red areas were most probably obtained by simple burnishing of the body; the dark red additions, on the other hand, are the likely result of a partial re‐oxidation of a clay–ochre mixture.     

THE SCIENTIFIC IDENTIFICATION OF ARCHAEOLOGICAL JET-LIKE ARTEFACTS

Jet has been widely used in the past for jewellery but was just one of a range of black lithic materials employed. When worked into small objects these materials can be visually indistinguishable, yet discrimination is important because of the restricted occurrence of jet. X-ray fluorescence (XRF) is a rapid non-destructive discriminatory technique, but not all samples are clearly classified, and inhomogeneity may pose problems. A reassessment of the use of XRF is reported. Other techniques considered include electron spin resonance, infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, scanning electron microscopy and X-radiography. These were tested on geological materials to define an effective methodology for archaeological material. The recommended approach is a combination of XRF and X-radiography, although preliminary Fourier transform infrared results showed promise. The X-ray techniques were tested on Romano-British assemblages from Catterick and Stanwick.     

ANALYTICAL INVESTIGATION OF ARCHAEOLOGICAL POWDERS FROM GÖLTEPE (TURKEY)*

Nine powder samples originating from the archaeometallurgical she in Göltepe, southern central Turkey, have been analysed. Bulk analyses, using X-ray fluorescence and X-ruy photoelectron spectroscopy, and single particle analyses, using electron probe X-ray microanalysis, were carried out. The analyses were focused on determining the inorganic elemental composition of the samples and the distribution of particle types in the nine powder samples. In addition, the powder samples were classified on the basis of their elemental composition using multivariate techniques. The objective of this study was to characterize the powder samples and to establish an association with archaeological data from the site     

LUMINESCENCE DATING OF SEDIMENTS—THE DETECTION OF HIGH EQUIVALENT DOSE GRAINS USING AN IMAGING PHOTON DETECTOR*

In this paper we describe quantitative measurements on the thermoluminescence of many single grains, made with an imaging photon detector. In several of the sediments examined a few bright grains were found which had a high equivalent dose (ED). Physical measurements made on these grains using binocular microscopy and analytical scanning microscopy enabled several possible explanations for the causes of the high ED grains to be rejected. Insufficient bleaching at deposition or the intrusion of grains from an older sediment were identified as the most probable explanation for these grains.     

ALTERATION PROCESSES OF POTTERY IN LAGOON‐LIKE ENVIRONMENTS

Post‐depositional processes in pottery can give rise to chemical and mineralogical alterations, the extent of which is closely related not only to the microstructure and composition of the potsherds, but also to the chemical–physical conditions of the burial environment. The present paper describes the characterization of post‐depositional alterations and identification of processes involving pottery buried in lagoon‐like environments. A set of various types of Roman transport amphorae and African Red Slip ware (ARS), collected from two archaeological sites characterized by a lagoon‐like depositional environment and showing evident changes in the original colours, was analysed by a combination of microstructural, mineralogical and microchemical approaches. The formation of pyrite after hematite, jarosite after pyrite and microstructural substitution features are interpreted here in terms of the chemico‐physical conditions of the burial environment and their evolution in time.     

AN INVESTIGATION INTO THE RELATIONSHIP BETWEEN THE RAW MATERIALS USED IN THE PRODUCTION OF CHINESE PORCELAIN AND STONEWARE BODIES AND THE RESULTING MICROSTRUCTURES*

The microstructures of porcelain and stoneware bodies from north and south China, spanning the period from the Tang to the Ming dynasty (7th–17th centuries ad ), were examined in polished sections in a scanning electron microscope (SEM) after etching the sections with hydrofluoric acid (HF). Mullite, present as fine, mainly elongated crystals, is the dominant crystalline phase observed. The bulk chemical compositions of the bodies are determined by energy‐dispersive spectrometry in the SEM, and the relative amounts of mullite and quartz present in the different ceramics are estimated from X‐ray diffraction measurements. Mullite formed from areas of kaolinitic clay, mica particles and feldspar particles is distinguished through a combination of the arrangement of the mullite crystals, and the associated SiO₂/Al₂O₃ wt% concentration ratios. It is shown that very different microstructures are observed in ceramic bodies produced using kaolinitic clay from north China (Ding porcelain and Jun stoneware), porcelain stone from south China (qingbai and underglaze blue porcelain and Longquan stoneware), and stoneware clays from south China (Yue and Guan stonewares). Therefore, SEM examination of HF‐etched, polished sections of the bodies of high‐refractory ceramics has considerable potential for investigating the raw materials used in their production.     

BLACK AND RED GRANITES IN THE EGYPTIAN ANTIQUITY MUSEUM OF TURIN: A MINERO‐PETROGRAPHIC AND PROVENANCE STUDY

A recent project to investigate the stone artefacts preserved in the Egyptian Antiquity Museum of Turin has been undertaken, with the aim of supplying their systematic classification and suggesting the provenance site of the original raw materials. This paper focuses on seven sculptures dating back to the New Kingdom (18th–19th Dynasties): the statue of Ramses II, three of the 21 sculptures of the goddess Sekhmet, the statue of the goddess Hathor, the Ram‐headed Sphinx and the sarcophagus lid of Nefertari. Petrographic observations have shown that all the sculptures are made of granitoid rocks, with variable composition from granite to granodiorite and tonalite. The observation of strong macroscopic analogies with the so‐called black and red granites outcropping in the Aswan area has suggested a common origin of all the raw materials used for their manufacture. In order to verify this provenance hypothesis, several samples were collected in the Aswan quarry districts. According to results of a minero‐petrographic and geochemical comparison between the statues and the Aswan quarry samples, it was possible to identify the source area of the stone sculptures and finally to highlight the importance of an archaeometric approach to the solution of archaeological problems.     

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.     

PREHISTORIC WALL PAINTINGS: THE CASE OF THE DOMUS DE JANAS NECROPOLIS (SARDINIA,ITALY)*

The Domus de Janas (Home of the Fairies, or Home of the Witches) are Neolithic hypogea located throughout Sardinia (Italy) and decorated with red and black wall paintings. The objective of this study was to define the painting technique through the analytical characterization of the pigments and binding media. Samples of painting film from different graves have been examined by means of various analytical techniques. XRD, Raman and SEM–EDX analyses identified the red and black pigments respectively as red ochre rich in hematite and carbon black, while GC–MS analyses characterized the organic binder as egg.     

CHARACTERIZATION OF RED‐COLOURED SLIPS (ALMAGRA) ON ISLAMIC CERAMICS IN MUSLIM SPAIN*

Small objects found in Islamic (eleventh‐century) kilns excavated in Zaragoza (Spain) were studied to determine the nature of the red coating of almagra pottery. Ceramics with almagra decoration were completely coated with a glossy deep‐red layer, a slip, applied to the body before firing. Chemical and mineralogical studies were carried out, together with analysis of a surface treatment with organic compounds. The results of this study confirm that almagra ceramics were produced by means of a specific and elaborate process (slip preparation, firing and wax application), demonstrating the introduction of this slip into local production during the Islamic period.