AN UPDATED,MULTI‐METHOD DATABASE OF EPHESOS MARBLES,INCLUDING WHITE,GRECO SCRITTO AND BIGIO VARIETIES*

An updated database of Ephesos marbles including 244 samples from 16 quarrying districts is reported. The unknown Greco Scritto quarries near Hasançavuslar and the Bigio marbles from the quarries of Belevi and of Mt Panayir are also presented. The paper, however, is mostly devoted to the identification of the Ephesos white marbles, whereas the problems posed by the Bigio and Greco Scritto varieties are deferred to future work. The samples have been characterized by isotopic analysis, EPR spectroscopy and additional petrographic and optical properties. Owing to the complex geology of the region, the white marbles of Ephesos exhibit rather inhomogeneous properties and are conveniently classified into four marble groups, which can be almost completely discriminated. The problem of distinguishing the Ephesos white marbles from other similar varieties has been dealt with by statistically comparing the Ephesos samples with all the similar, medium‐grained varieties present in the marble database. Although some of the four Ephesos groups can be reliably identified, general solution of the discriminant problem is difficult. Historical archaeological information is needed to reduce the complexity of the problem by eliminating unlikely provenances. In this way relevant problems, such as the discrimination between Ephesos and Proconnesos marbles, can be solved.     

PROGRESS REVIEW OF THE SCIENTIFIC STUDY OF CHINESE ANCIENT JADE

The interdisciplinary study of cultural heritage has become a scholarly hotspot in archaeology. Ancient jade serves as an important symbol of Chinese traditional culture, so the study of it is a critical part of this trend. The past 30 years have witnessed great progress in research on ancient jade, with the involvement of basic theory and the technological application of many science subjects. This paper summarizes the research status, methodology and prospects in the research on raw material (jade texture), provenance and secondary change of Chinese ancient jade, in the hope of benefiting future studies of ancient jade.     

IBERIAN CERAMIC PRODUCTION FROM BASTI (BAZA,SPAIN): FIRST GEOCHEMICAL,MINERALOGICAL AND TEXTURAL CHARACTERIZATION

Ceramic fragments from the archaeological excavation of the Iberian–Roman city of Basti (Spain) were studied from a geochemical point of view and by applying a statistical tool to X‐ray fluorescence data to discover similarities between ceramic materials. The analysis of these samples was completed by performing a mineralogical analysis, textural observation, and by characterizing the porous system and the colour of the pieces. Our results enabled us to identify the source area of the clayey raw material in the surroundings of Basti and to estimate the firing temperature of the ceramics. Differences in the chemistry were confirmed by characteristics of the pastes and the mineralogical composition of the pieces. Some samples show black cores, which would suggest the presence of organic matter in the raw material and fast firing of the ceramics. The main types of temper were quartz grains and gneiss fragments, although carbonate grains were also identified. Our evidence suggests that most of the samples were well fired. New silicate phases were found to be present in several samples. The mercury intrusion porosimetry verified and confirmed the firing temperature of non‐carbonated samples. Colorimetry showed that the colour of the ceramics varied according to the amount of CaO that they contained.     

THE ARCHAEOINTENSITY OF THE EARTH'S MAGNETIC FIELD RETRIEVED FROM PAMPEAN CERAMICS (SOUTH AMERICA)

Absolute intensity determinations using the Coe variant of the Thellier method have been carried out on some selected pottery fragments collected in the wetlands of the lower Paraná (Pampean region, Argentina) in order to construct the first archaeointensity master curve for South America. Associated radiometric ages range between 1640 ± 70 and 730 ± 70 bp . Twenty‐one samples (five fragments) out of 46 studied (eight fragments) provided successful absolute intensity determinations. The fragment‐mean archaeointensity values obtained in this study range from 21.9 ± 2.3 to 42.6 ± 5.4 μT, with corresponding virtual axial dipole moments (VADMs) ranging from 4.0 ± 0.5 to 8.1 ± 1.0 x 10²²Am². This corresponds to a mean VADM of (6.4 ± 1.8) × 10²² Am². The synthetic record retrieved from southern Argentina and Brazil consists of 17 mean archaeointensities distributed between approximately ad 700 and ad 1700. The data set shows several distinct periods of fluctuations of quite large intensity. However, most data are concentrated into a relatively narrow time period from ad 950 to ad 1300. Three general features may be detected: the time intervals from about ad 950 to 1130 and 1350 to 1480 are characterized by quite monotonic increases of geomagnetic intensity, while some decrease is observed from ad 1150 to 1280. These variations may be speculatively correlated to climate changes over multi‐decadal time scales. Important differences are observed between the data and the geomagnetic field predictions derived from recently reported global models, which reinforces the importance of regional reference curves for dating purposes.     

COMMENT: CHEMICAL AND MINERALOGICAL APPROACHES TO CERAMIC PROVENANCE DETERMINATION

This comment concerns an ‘absolutist’ perspective on the superiority of mineralogical analysis over chemical analysis for the determination of ceramic provenance. This point of view has appeared in the literature in recent years, but it has not been justified and is not justifiable. Mineralogy and chemistry are complementary. They measure different things and are best used in combination to generate secure, geographically specific ceramic source assignments.     

DIATOMS AND CERAMIC PROVENANCE: A CAUTIONARY TALE*

In order to answer the age‐old question of whether a given pot was manufactured locally or elsewhere, some archaeologists have turned to geoarchaeological or bioarchaeological methods such as diatom analysis to establish potential clay sources. In this paper, we highlight the complexity of diatom analysis and illustrate how diatoms potentially coming from several sources may be introduced at different stages during the ceramic manufacturing process. Finally, we proceed to evaluate the reliability of diatom analysis as an archaeometric measurement for ceramic provenance, concluding that it may have a more limited usefulness within archaeology than its current frequency of use would indicate.     

THE DETERMINATION OF BRICK PROVENANCE AND TECHNOLOGY USING ANALYTICAL TECHNIQUES FROM THE PHYSICAL SCIENCES*†

This work applies established analytical techniques from the physical sciences to Irish brick, in order to gather evidence of ceramic technologies, provenance and sources of raw materials. Petrographic microscopy, X‐ray diffractometry and scanning electron microscopy with an energy‐dispersive X‐ray diffraction attachment were used to study the brick of Rathfarham Castle, Dublin, built c. 1618, where clay brick was introduced in 1771. Local clay was fired in the laboratory and analysed in a similar manner. The petrography of the pointing mortar was studied in order to gather evidence of ceramic provenance. This paper concludes that the brick was hand‐ moulded with a silica‐based, predominantly non‐calcareous clay of glacial origin, gathered locally, including fluxes and a high percentage of non‐plastic material. The mineralogy and petrography of the brick, together with the presence of pebbles and a coarse matrix, suggest that the raw clay was probably gathered from a glacial deposit. The presence of abundant pebbles and colour inhomogeneities suggests a lack of processing of the raw clay. The brick was probably fired in clamps at top firing temperatures ranging from 750°C to above 900°C. Transformation of limestone temper involving the breakdown of calcite and the generation of calcium silicates, and the new formation of plagioclase, high‐temperature quartz, hematite and spinel were revealed. The presence of spinel in ‘hot spots’ indicates that fuel was added to the raw clay in order to assist firing.     

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.