Lead pigments and related tools at Akrotiri,Thera, Greece. Provenance and application techniques

This paper refers to an investigation of finds that are associated with the raw materials and tools for the preparation or use of lead pigments at Akrotiri on Thera, Greece, during the Early, Middle and Late Cycladic Bronze Age (c. 3000–1600 BC). For the detection and the preliminary characterisation of remains of pigments that were found on stone tools, the in situ application of X-Ray Fluorescence spectroscopy proved to be invaluable. In order to identify the chemical composition of the pigments and to investigate their provenance from a geological perspective, quantitative X-Ray Diffraction analysis was conducted. A thorough visual macro and microscopic examination of the morphology of the materials permitted the determination of physical features (colour, homogeneity, grain size) as indicators of their nature or degree of processing. Based on the results of these analyses, the traces of lead oxides that were detected on the stone tools are associated with specific collections of litharge items discovered at the settlement of Akrotiri, and probably provide evidence of their earliest use in preparing pigments.     

Coupling lead isotope analysis and petrography to characterize fabrics of storage and trade containers from Hala Sultan Tekke (Cyprus)*

Lead isotopes, thin‐ and sherd‐section analyses are coupled on pottery‐vessel fragments excavated from the Late Bronze Age site of Hala Sultan Tekke (south‐east Cyprus) and representing fabrics used for the production of storage and trade containers. The fabrics of the sherds are first described according to general macroscopic observations. Based on the different fabrics identified, a petrographic analysis is carried out on thin sections and compared to lead isotope results on the same samples. This study shows that a specific fabric corresponds to a specific lead isotopic composition and proposes different sources for the various groups of associated sherds/fabrics. It also demonstrates the compatibility and complementarity of petrography and lead isotopes within pottery provenance study.     

Moving metals or indigenous mining? Provenancing Scandinavian Bronze Age artefacts by lead isotopes and trace elements

The aim of this study is to further the discussion as to whether copper was extracted locally or imported to Sweden during the Bronze Age or if both of these practices could have coexisted. For this purpose, we have carried out lead isotope and chemical analyses of 33 bronze items, dated between 1600BC and 700BC. Among these are the famous Fröslunda shields and the large scrap hoard from Bräckan and other items from three regions in southern Sweden which are also renowned for their richness in copper ores. It is obvious from a comparison that the element and lead isotope compositions of the studied bronze items diverge greatly from those of spatially associated copper ores. Nor is there any good resemblance with other ores from Scandinavia, and it is concluded that the copper in these items must have been imported from elsewhere. The results furthermore indicate that there are variations in metal supply that are related to chronology, in agreement with other artefacts from Scandinavia as well as from other parts of Europe. Altogether these circumstances open up for a discussion regarding Scandinavia’s role in the maritime networks during the Bronze Age.     

The Asiatic marbles of the Hadrian's Villa at Tivoli

Multi-method provenance studies, including petrographic, isotopic, electron paramagnetic resonance and trace chemical analyses, have been carried out on 20 white, 9 black and 1 red artifacts purposely selected to investigate the use and distribution of sculptural marbles at the Hadrian's Villa. A large fraction of the marbles tested (21 samples, 70%) are shown to be from Asia Minor, mostly originating from the recently discovered site of Göktepe near Aphrodisias (15 or 71%). All the 9 black samples investigated and 6 out of 11 white Asiatic marbles are from Göktepe, the remaining being Docimium marble from Iscehisar (4 samples) and Aphrodisias marble from the city quarries (1 sample). The single red sculpture tested proved to be Carian red marble from the Iasos quarries, whereas non-Asiatic marbles include 3 Carrara and 6 Pentelicon samples. The selection of marbles tested is preliminary and incomplete, but, despite this, the results are noteworthy, especially since the marble of other sculptures from the Villa has already been identified as Göktepe. Together with other published results, the marble distribution at the Hadrian's Villa seems to suggest that the use of sculptural marbles in the Roman world underwent considerable changes around the turn of the 1st and the 2nd century AD. The evidence supporting this hypothesis is briefly summarized in the conclusions.     

MEDIEVAL SILVER PRODUCTION AROUND SIJILMÂSA,MOROCCO

Sijilmâsa (south-east Morocco) was one of the most strategic cities in a far-reaching exchange network, that is, the Trans-Saharan trade, linking the Maghreb with West Africa during the medieval period (from the 8^th to the 15^th century CE). It was also one of the most important gold and silver monetary workshops at the time. If gold came from West Africa, we know from written sources that silver was produced in Morocco, although archaeological evidence of silver mining and smelting has remained elusive. Thanks to a thorough analysis of the lead isotopic data from silver mining districts in Morocco and from ores and slags of our study, we were able to refine the tracing of our materials and provide tangible evidence of medieval mining in the close hinterland of Sijilmâsa city.     

Isotope sourcing of prehistoric willow and tule textiles recovered from western Great Basin rock shelters and caves – proof of concept

Isotope and trace-metal analyses were used to determine the origin of plants used to manufacture prehistoric textiles (basketry and matting) from archaeological sites in the western Great Basin. Research focused on strontium (⁸⁷Sr/⁸⁶Sr) and oxygen (¹⁸O/¹⁶O) isotope ratios of willow (Salix sp.) and tule (Schoenoplectus sp.), the dominant raw materials in Great Basin textiles. The oxygen-isotope data indicated that the willow and tule used to produce the textiles were harvested from the banks of rivers or in marshes characterized by flowing water and not from lakes or sinks. The strontium-isotope data were useful in showing which plants came from the Humboldt River and which came from rivers headed in the Sierra Nevada.     

Roman lead mining in Germany: its origin and development through time deduced from lead isotope provenance studies

High precision lead isotope analysis by Multi Collector Inductively Coupled Plasma Mass Spectrometry was applied to the investigation of more than 240 Roman lead objects from several archaeological sites in Germany, in order to obtain information on the pattern of Roman mining activity and ore processing in the area. Measurements of ore samples from German deposits east (Siegerland, Lahn-Dill, Ems) and west of the Rhine (Eifel, Hunsrueck) were made and supplemented with data from literature to create a data bank of lead isotope ratios of European lead occurrences. Comparing the isotope ratios of lead objects with those from German ore deposits shows that the source of over 85% of the objects is Eifel ore deposits, but that, in the early years, the Romans also imported lead from the Southern Massif Central and later from Britain.     

Local recipes or distant commodities? Lead isotope and chemical compositional analysis of glaze paints from the Salinas pueblos,New Mexico

For nearly four hundred years, Pueblo potters in the Rio Grande Valley of New Mexico produced technologically innovative glaze-decorated bowls and exchanged them widely among different villages. While potential sources of lead ores used to make glaze paints are found throughout the Rio Grande Valley region, researchers have only recently begun to identify which ore sources potters exploited and to understand the social and economic factors underlying patterns of ore resource use. In this paper we use stable lead isotope and electron microprobe analysis of glaze paints on Rio Grande Glaze Ware made at two Salinas pueblos to identify ore sources and glaze recipes used by their potters. Despite some isotopic overlap of ore sources, the lead isotope data point to regular exploitation of ores from the Socorro area of the southern Rio Grande. Salinas potters apparently used other sources as well, and likely mixed ores from different sources. We also identify four local glaze recipes that appear to incorporate multiple ore sources, suggesting that Salinas potters obtained raw ores rather than finished glaze paints.     

海昏侯墓出土马蹄金、麟趾金内嵌物的分析研究

南昌西汉海昏侯墓发掘出土了数量较多的马蹄金,为汉代黄金货币的研究工作提供了宝贵资料,出土马蹄金内均存在镶嵌物,大部分腐蚀严重。结合偏光显微分析、背散射扫描电镜\能谱、红外光谱、X射线衍射光谱对海昏侯墓主棺头箱出土的部分马蹄金内嵌物进行分析研究,依据分析结果将马蹄金内嵌物分为透闪石软玉、蛋白石、铅钡玻璃和疑似高铅玻璃4种类型。其中,铅钡玻璃基本保留玻璃态,腐蚀产物随着埋藏环境的变化存在二次结晶现象,腐蚀的最终产物是碳酸铅;疑似高铅玻璃表现出完全不同的腐蚀状态,外层硅质成分较高形成较为致密的壳状结构,内部碳酸铅以葡萄状填充在少量的硅质成分中。研究结果可为后续的保护处理与马蹄金、麟趾金的复制工作提供理论支持。