Application of X-ray fluorescence imaging to ceramics from the American Southwest

We have used synchrotron-based X-ray fluorescence imaging (XRFI) to examine sherds of painted ceramics from prehistoric cultures of the American Southwest. These sherds are very well suited to XRFI analysis. Paints can generally be detected and distinguished by the fluorescence intensities of their constituent elements. Spatial maps of element distributions yield the spatial distribution of pigments. Pigments can be distinguished that are (or have become) visually similar; layers that have been obscured by overpainting can be examined; and pigment residues can be distinguished from surface contaminants deposited after painting and firing. As a result, XRFI allows the painted motifs to be clarified and hidden features to be revealed. Furthermore, the very rapid scanning and high sensitivity elemental detection possible with synchrotron-based XRFI facilitate measurements on large collections of sherds, allowing an integrative rather than anecdotal analysis.     

Multi-method (FTIR,XRD, PXRF) analysis of Ertebølle pottery ceramics from Scania,southern Sweden

A combination of Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD) and portable X-ray fluorescence spectroscopy (PXRF) was used on the clay fraction of Ertebølle ceramics from several Late Mesolithic sites in Scania, southern Sweden. The aim was to provide up-to-date information about clay types used during that period within the Scanian Ertebølle cultural unit, and to elucidate social aspects relevant to the organization of pottery production and the role of ceramics in the local societies. The results suggest similar clay preferences across the sites, site-based pottery production using local clays and zero mobility of ceramics between the sites. The chemical separation of the ceramics from the site of Soldattorpet into two compositional groups suggests possible multigroup occupation. The origins of aromatic hydrocarbons, extracted previously from the ceramic matrix of the vessels during a lipid residue study, were also investigated, and a discussion is provided.     

中心-边缘:近代中国经济格局的转变

文章从国际尺度和国家尺度对近代中国的经济格局进行考察,认为1800年前中国是世界经济中心之一,近代中国则成为欧美制成品的销售地和原材料的来源地,中国由此转变为世界经济的边缘。这种世界经济格局又影响中国内部的经济格局,原来南北经济差距转变为东西差距,东部沿海成为中国经济的中心区,西部则成为中国经济的边缘。     

Archaeometric investigation of Roman tesserae from Herculaneum (Italy) by the combined use of complementary micro-destructive analytical techniques

Vitreous tesserae from two mosaics in Herculaneum (Italy) dating from the 1st century AD have been investigated in order to gather information on Imperial Age opaque glass. The combined use of complementary micro-destructive analytical techniques, namely optical microscopy (OM), scanning electron microscopy (SEM) with energy dispersive spectrometry (EDS), inductively coupled plasma-mass spectrometry (ICP-MS), transmission electron microscopy (TEM), and X-ray powder diffraction (XRPD) allowed to define the nature of formers, fluxes, chromophores and opacifying compounds and to determine the type of raw materials employed for their introduction. The results confirmed the high technological level of Imperial Age glassmakers and clarified some details of the production processes. Experimental data have been obtained concerning formation of antimony-based opacifiers. The presence of tin-containing Ca- and Pb-antimonates has been ascertained in various green, yellow and turquoise tesserae. Moreover, unusual divergences from the established Roman age ‘low magnesia–low potash’ (LMLK) glass composition have been found for some red and green samples.