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.     

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.