Evidence of early medieval soda ash glass in the archaeological site of San Genesio (Tuscany)

The early medieval period marks an important turning point in the history of glassmaking, since it comprises the transition period between the mineral-based silica-soda-lime glass of the Roman tradition and the plant ash-based glass. With the aim of expanding the knowledge on the glass recipes and technologies of this period, 37 glass samples were analyzed, originating from the archaeological excavations of San Genesio (Tuscany) and dated from the fourth to the eleventh century. The major and minor element concentrations were measured with SEM-EDX, while the trace elements were quantified with LA-ICP-MS. The results were compared with published compositions of glass samples of similar age in order to highlight differences and similarities. The results offer a very interesting view on the glass circulation in the religious/residential/manufacturing center of San Genesio in the early medieval period. Most of the glass has a typical late-Roman composition, but some glass fragments are identified as soda ash glass. These are among the earliest medieval ash-fluxed glasses ever found in the Italian peninsula.     

Composition of white paste inlay on the pottery from sites of the 10th–8th centuries bce in the northern Pontic region

For the first time, the mineralogical–geochemical compositions of the white paste inlay found on vessels from sites (10th–8th centuries bce ) in the northern Pontic region are investigated. Samples of the white paste on vessels from settlements, burials of sedentary groups and graves of early nomads were analysed by means of scanning electron microscopy with energy-dispersive X-ray spectrometry (SEM-EDX) and X-ray diffraction (XRD) methods. Between the 10th and eighth centuries bce , various innovations occurred in the working area. Iron processing technology and the manufacture of iron products also appeared. Other innovations were changes in the manufacturing technology of ceramics. A high-quality, polished/burnished surface and ornaments with white paste inlay are characteristic of this pottery. When collating white paste mixtures of different European sites, similarities in the preparation of white paste recipes for vessels from the Balkan and northern Pontic regions are evident. During the Early Iron Age, further changes in the manufacture of the white paste were discovered in the northern Pontic region, namely the application of high-temperature firing to obtain more resistant synthesized material such as calcium alumosilicates and silicates (wollastonite). The development of iron metallurgy in this period could provide a basis for the elaboration of new techniques in ceramic manufacture.     

On the provenance and manufacture of red-slipped fine ware from ancient Cassope (NW Greece): evidence by X-ray analytical methods

Energy-dispersive X-ray fluorescence spectroscopy was used to characterize red-slipped pottery (2nd–1st century BC) from ancient Cassope, north-western Greece. The compositional data were statistically treated by principal component analysis and chemical groups were established, representing locally produced and imported items. Mineralogical investigation by X-ray diffraction indicated firing temperatures in the range from 850 to 1000 °C for most of the sherds, while one group consisted of over-fired items, possibly in excess of 1050 °C. The morphology and elemental composition of the ceramic bodies and surface slips were examined through scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. The analyses revealed that different pottery groups exhibit surface slips of different nature, in terms of thickness, degree of vitrification and elemental composition. Overall, the diversity in technological characteristics of the examined sherds is indicative of the socio-economic conditions prevailing in Cassopaea during the late Hellenistic period.     

Characterization of prehispanic cosmetics found in a burial of the ancient city of Teotihuacan (Mexico)

The present paper reports the chemical data obtained on samples of pigmenting materials contained in 31 miniature vessels found in a burial found in Teopancazco, a multiethnic neighborhood center located in the southeastern sector of the archaeological site of Teotihuacan (Central Mexico) and the analytical protocol established for the complete characterization of these archaeological materials. For this purpose a multi-technique approach based on the combination of several non destructive and micro-destructive instrumental techniques, namely, light microscopy (LM), scanning electron microscopy-X-ray microanalysis (SEM-EDX), transmission electron microscopy (TEM), voltammetry of microparticles (VMP), X-ray microdiffraction (μXRD), X-ray diffraction (XRD), UV-Vis spectrophotometry, FTIR spectroscopy and gas chromatography-mass spectrometry (GC-MS) has been developed in an attempt to completely characterize these materials. These instrumental techniques provide reliable and complementary data including elemental and mineralogical composition, identification of functional groups as well as speciation studies of electroactive species. Among the most relevant findings, volcanic pyroclastic rocks and clayey soils, most probably, from the Teotihuacan valley as well as galena, jarosite and mica from other provenances in Mesoamerica, have been identified. Charcoal and Ocote resin have also been identified. The chemical composition of the samples is discussed with a view to the possible function as cosmetic materials and their use in funerary rites. The results have been critically compared with those others obtained in other ancient civilizations. The study carried out on the materials found in the burial 105 is especially relevant insofar it represents the first evidence, scientifically characterized, of the use of cosmetics in Mesoamerica at this early period (AD 200-550).     

Archaeometric investigation of pottery from funerary gifts in Kal-e Chendar,Shami (Khuzestan,Iran)

Thirty fragments of red slip, glazed, common and cooking ware from Hellenistic and Parthian tombs at Kal-e Chendar in Shami (Iran) were investigated. Petrographic assemblage and chemometric evaluation of chemical data collected most samples in a large cluster, suggesting a common provenance, even in a quite wide area which includes Izeh plain and lowland Susiana, and underlining the presence of smaller very distinguished groupings. Surface finishing layers (both glazes and red slips) showed a high degree of alteration of their morphological features. Blue glazes are typical plant-ash, with copper as a colouring agent.     

The manufacturing process of 3rd millennium BC bone based incrusted pottery decoration from the Middle Guadiana river basin (Badajoz,Spain)

The aim of this study is to present the manufacturing process developed on 3rd millennium BC white incrusted pottery from the middle Guadiana River basin (Badajoz, Spain), alongside the analytical procedure developed to determine the nature of these incrustations. The analytical procedure developed in this paper will assess the nature of these incrustations as burnt bone and in fewer cases as calcium carbonate, turning upside down the usual tendency for the Iberian Peninsula, where calcium carbonate has been the only kind of incrustation identified up until now. The analytical facilities used are: SEM-EDX, XRF microprobe, XRD and FTIR. The assessment of the nature of the incrustations as burnt bone has been a hazardous task and it has been necessary to develop a procedure using several analytical techniques and reference materials.     

Raw materials for medieval to post-medieval Tuscan glassmaking: new insight from LA-ICP-MS analyses

LA-ICP-MS analyses were performed on a set of Tuscan (post) medieval archaeological glass finds dated to the 13–16th century in order to quantitatively determine the trace element contents. The results are used for defining and distinguishing several compositional groups. The trace element data are consistent with the distinctions obtained by considering the major element data determined via quantitative SEM-EDX, but allow to obtain new insights into the nature and quality of the silica sources employed and the presumed method of ash purification.     

山西太原纯阳宫所藏明代一尊星宿彩塑颜料分析

利用现代科技分析手段提取古代彩塑信息并与文献结合,可以推断其工艺、材料和制作时间,进而确定其历史价值、科学价值和艺术价值,为艺术史研究和保护修复提供信息与帮助。因此,本工作利用三维视频显微镜(3D Video Microscope)、偏光显微镜(PLM)、拉曼光谱(Raman)、扫描电子显微镜与能谱仪(SEMEDX)、X-射线衍射仪(XRD)和大腔体微束X-射线荧光光谱仪(XRF)等分析了山西太原纯阳宫所藏一尊明代道教星宿彩塑脱落样品,发现彩塑经过多次重绘。其中星宿足部经过四次重绘,从胎体至表面层使用的黑色颜料为炭黑(C),绿色颜料为氯铜矿(CuCl_2·3Cu(OH)_2),白色颜料为铅白(PbCO_3),褐红色颜料为靛青(C_6H_(10)N_2O_2)与黄丹(PbO)的混合物。彩塑头部经过两次重绘,分别使用了群青(Na_(6-8)Al_6Si_6O_(24)(S_(2-4))和靛青。彩塑躯干部位表层红色颜料为朱砂(HgS)和铅丹(Pb_3O_4)的混合物,黄色颜料为铅铬黄(PbCrO_4),蓝色颜料为群青,绿色颜料为铅铬黄(PbCrO_4)与群青的混合物。彩塑白粉层成分为石英(SiO_2)与高岭土(Al_2Si_2O_7·2H_2O)的混合物。分析结果表明,此尊星宿彩塑在过去的数百年间曾经多次重绘或修葺,根据不同白粉层成分组成相近判断,保存该彩塑群的寺观有将高岭土作为白粉层的传统。研究结果可为保护材料和修复技术的选择提供信息和依据。