Transitions in Islamic plant-ash glass vessels: on-site chemical analyses conducted at the Raya/al-Tur area on the Sinai Peninsula in Egypt

This study focuses on the chemical composition of Islamic plant-ash glass (dated from the 9th to 11th centuries) excavated from the Raya/al-Tur area on the South Sinai in Egypt. Plant-ash glass objects from the Raya site were classified into three compositional types based on on-site chemical analyses with a portable X-ray fluorescence spectrometer. Based on typological characteristics and chemical composition comparisons with contemporary glass objects from other Islamic sites, one hypothesis holds that plant-ash glass objects produced in the Syria–Palestine or Mesopotamian regions could have been imported to Raya during the 9th to 10th centuries. In particular, some colorless glass vessels with a high magnesium/calcium ratio were noted to exhibit post-Sassanian cut decorations. Conversely, most of the bluish-green plant-ash glass objects from the Monastery of Wadi al-Tur near the Raya site exhibited relatively high levels of aluminum, titanium, iron, and lead. These pieces were likely produced during the Fatimid period (late 10th to 12th centuries), and based on their elemental composition, possibly originated in Egypt. The present work provides a greater understanding of chronological changes in post-9th century Islamic plant-ash glasses and the development of social and commercial networks within the Middle Eastern area.     

中国传统灰土灰浆强度增强方法研究

中国传统灰土灰浆中水硬性凝胶材料-水合硅酸钙和水合硅酸铝的形成可以大幅度提高其强度,但在自然条件下生成此类水硬性化合物需要很长时间。本文借鉴现代水泥工艺中利用焙烧黏土材料可提高火山灰活性的原理,从而有效缩短形成水硬性化合物的反应时间,在短时间内大大提高灰浆的强度。以此为出发点,加工制备性能优良的灰浆材料,为传统砌体建筑的保护提供适宜的保护修复材料。     

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.     

河南禹县阳翟遗址出土古玻璃的科学分析

考古发掘中出土玻璃器历来受到研究者的重视。其中,通过对古玻璃化学组成和结构特征的科学分析,以探讨其工艺技术及产地问题,是古玻璃研究的重要组成部分。经过多年的研究,学界已对中国古代玻璃的起源、工艺技术特点及产地等问题     

Tongan and Samoan volcanic glass: pXRF analysis and implications for constructs of ancestral Polynesian society

A provenance study of volcanic glass specimens from 12 archaeological sites in the Kingdom of Tonga is carried out employing pXRF (portable X-ray fluorescence) analysis. To accomplish this, volcanic glass samples from previously identified sources in northern Tonga and the adjacent islands of Samoa are analyzed. Results indicate inter-island voyaging and interaction over a 600 km linear distance along the Tongan island chain from first Lapita settlement ca 2900 BP throughout later prehistory. Tongan volcanic glass, however, is not found in Samoa and, with the exception of one late prehistoric specimen, Samoan volcanic glass is not present in Tonga. This distribution challenges current concepts of an integrated ancestral society and homeland common to Tonga and Samoa from the Lapita period onward.     

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.     

A chronometric tool for Hawaiian archaeology: the hydration dating of Pu'u Wa'awa'a trachytic glass

The Pu'u Wa'awa'a trachytic glass deposit located on the Big Island of Hawai'i was a source of lithic tools for much of Hawaiian prehistory. Routinely encountered at habitation sites, the glass has the potential to provide absolute dates based upon the degree of surface hydration. Infrared photoacoustic spectroscopy and secondary ion mass spectrometry were used to monitor the diffusion of water in archaeological and experimental samples. Accelerated laboratory hydration experiments show that water diffusion in trachytic glass containing a structural water content of 0.16% ± 0.03% is linear with time. Application of the calibration to trachytic glass artifacts from the Kahalu'u habitation cave have produced chronometric dates in the 17th–18th centuries. These age estimates are in agreement with radiocarbon dates and artifactual data that bracket the site occupation. However, the glass dates do not correlate well with site stratigraphy and this suggests that slight sample imperfections that retain water may be one factor that results in ages that are too early for later occupation levels.     

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.