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International audience; The city of Demetrias was founded in the early third century BCE and became the second capital of the Macedonian kingdom and an important naval station for the Macedonian fleet. Demetrias flourished from third until the first centuries BCE when its importance started to diminish. In the present study we examine the chemical composition of finished glass objects from the north cemetery of ancient Demetrias dated to the Hellenistic times looking at the specific chemical signature in order to better understand the various compositional groups of the period.

International audience; Obsidian-tempered ceramics represent a typical production of the Chalcolithic period in the southern Caucasus. Previous studies have already assessed the viability of LA-ICP-MS analysis to identify the provenance of the obsidian temper contained in the ceramic paste. In this article the results of the analyses of the obsidian-tempered ceramics and of the obsidian lithic artefacts from the sites of Aratashen (Armenia) and Mentesh Tepe (Azerbaidjan) are compared. The aim of this comparison is to define analogies and differences in the modalities of acquisition of the obsidian as they are revealed by ceramic and lithic production at two sites that were localised at different distances from primary and secondary sources of obsidian. The results of this comparison allowed us to highlight different modalities of provisioning and exploitation of the same raw material by knappers and potters.

International audience; The medieval port city of Sīrāf (ca. 800–1050 CE) on the north coast of the Persian/Arabian Gulf linked the core lands of the ‘Abbāsid caliphate with India, China, Africa, and beyond. 101 glass fragments recovered from the 1966–1973 excavations at Sīrāf and now at the Corning Museum of Glass were analysed using LA-ICPMS in order to explore the glassmaking raw materials and technology of the objects found within the city, as well as to address issues of the production and trade of glass during the Islamic period. The results indicate that the main groups of glass at Sīrāf likely date to the 9th–early 11th centuries and can be subdivided by the trace elements zirconium and chromium. Chemical matches with some likely Indian glass, and with glass finds from South and Southeast Asia, underline the pivotal role of the Gulf in the eastward movement of Islamic glass via the Indian Ocean trade network, as well as the influx of Indian glass into the Islamic world. Glass bangles and a small number of vessel fragments likely date to the late 11th century or later, and their chemical compositions indicate different production origins.

International audience; Palestine and Egypt supplied the Mediterranean and Europe with virtually all of its glass for most of the first millennium CE. While the Muslim conquest in the 7th century saw major political and economic adjustment, immediate changes to material culture appear to have been minimal. This paper examines the impact of the Byzantine-Islamic transition on the natron glass industry of Palestine from the 7th to 12th century. A series of 133 well-contextualised glass vessels from selected excavations in modern day Israel have been analysed for major, minor and trace elements using LA-ICP-MS. These glasses are assigned to previously established primary production groups, allowing the elucidation of the chronology of key changes in glass production in the region. Results indicate a relatively abrupt compositional change in the late 7th - early 8th centuries, covering the reforming reigns of al-Malik and al-Walid, which marks the end of “Byzantine” glass production and the establishment of the furnaces at Bet Eli'ezer. At about this time there was an influx of glass of an Egyptian composition. Production of Bet Eli'ezer type glass appears to have been limited to a short time span, less than 50 years, after which natron glass production in Palestine ceased. Plant ash glass is first encountered in the late 8th-early 9th century, probably as a result of reduced local natron glass production creating the conditions in which plant ash glass technology was adopted. Egypt continued to produce natron glass for up to a century after its demise in Palestine. It is reasoned that the change and then collapse in natron glass production in Palestine may well have been as a consequence of a reduction in the quantities of available natron. This affected Palestine first, and Egypt up to 100 years later, which suggests that the factors causing the reduction in natron supply originated at the source and were long term and gradual, not short term events.

In this study facon-de-Venise glass objects from several Portuguese archaeological sites were studied aiming at characterising their chemical composition, discussing the raw materials and possible provenance. These objects were found during four archaeological excavations performed in Portugal (at Santa Clara-a-Velha Monastery (SCV) in Coimbra, Sao Joao de Tarouca Monastery in Lamego (SJT), Miguel Fernandes Square in Beja (PMF) and at the courtyard of the University of Coimbra (CPU)). Most fragments are dated to the 17th century, with only two objects being dated between the 14th and 15th centuries. These last two fragments, due to chronological reasons, can't be attributed to a facon de Venise production, but were included in this study for comparison. The glass composition was characterised by means of particle induced X-ray emission (μ-PIXE), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and UV–Vis reflectance spectroscopy. All thirty-one objects are composed by soda–lime–silica glass and the use of coastal plants as raw materials is suggested by the contents of MgO, K 2 O, P 2 O 5 and chlorine. The observed greyish/bluish glass hue was also investigated and UV–Vis analysis allowed one to identify Co and Fe as the cations responsible for that hue. Through the analysis of silica trace elements and of the flux agents it was possible to associate four objects, from the Santa Clara-a-Velha Monastery assemblage, to Venetian production (three objects of cristallo and one object of vitrum blanchum ) and to identify two other distinct production lines. One group comprising fragments from Sao Joao de Tarouca Monastery, presented medium alumina contents, differing from known facon-de-Venise production centres. The other group includes most fragments from Miguel Fernandes Square assemblage and has high alumina values, which, once again, is not consistent with any of the known facon-de-Venise production centres. For these reasons, the existence of new facon-de-Venise production centres is proposed.

International audience; Peter Francis Jr. has devoted much of his research to Indo-Pacific glass beads. These productions are among the emblematic objects made by South Asian glass workshops for nearly two millennia. Despite their wide distribution, both in Asia and Africa and in the Middle East, these tiny beads have never been reported in Western Europe. They have recently been found in large numbers on funerary sites in Merovingian Gaul, dated to between the middle of the 5th and the middle of the 6th century AD (mainly in the form of necklaces or clothing ornaments). Their presence stimulates reflection on the extensive trade between the Merovingian and the Indian worlds. This contribution discusses the technological, typological and chemical characteristics of these beads, as well as their use.

In the present work, a set of archaeological glass fragments belonging to a singular 17th century glass flask with gilded decoration was sampled and analyzed. The fragments were excavated in Coimbra, Portugal. The main focus of this study is to bring to light the flask production technique, in particular the gilding process, and additionally, to investigate the object's provenance based on the composition of the glass. A comprehensive survey of ancient and traditional glass gilding techniques is also presented. The glass and the gilded areas were characterized using micro energy dispersive X-ray fluorescence spectroscopy (μ-EDXRF), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS), X-ray electron probe micro-analysis (EPMA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The flask is made of soda-lime-silica glass and the use of coastal plant ashes is suggested by the relatively high content of MgO and K 2 O, as well as by the presence of chlorine. The high alumina content excludes a Venetian provenance, and with regard to the contents of Na 2 O, SiO 2 , K 2 O, and CaO, the glass composition is distinct from the facon-de-Venise glasses which have been studied, and only comparable to a few 17th century millefiori glasses, also recovered in Coimbra. Lead was detected in the gilded areas suggesting that a lead based mordant was used in the gilding process to promote the adhesion of the gold leaf to the glass during the low temperature reheating of the object. The gold leaf composition was determined by LA-ICP-MS, and it was possible to ascertain its purity: between 22 and 23 gold carats.

International audience; The West Mound of Tappeh Sang-e Chakhmaq, dated to c. 7100/7000 to 6700/6600 BCE, in the northeast region of Iranian Plateau, is one of the earliest known Neolithic villages east of Zagros Mountain that provides evidence of round-year occupation with mud brick architecture. Provenience studies have been conducted on seven pieces of obsidian artefacts, recovered from the 2009 sounding of the site. The analyses of the obsidian artifacts were done by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). The results show that all samples were extracted from Bingöl B and Bingöl A outcrops in west of the Lake Van, eastern Anatolia. The West Mound samples have important implication for the spread of the Neolithic from Zagros eastwards during the 8th millennium BCE or earlier.

We present compositional data for nearly 100 glass samples from Pergamon, western Turkey, spanning 1500 years from the Hellenistic to Late Byzantine and Islamic periods. The data shows the use of already-known Roman glass groups during the first half of the time frame, for imported vessels as well as locally worked glass. No compositional change is seen related to the introduction of glass blowing for either of the glass groups in use during this time. During the first half of the 1st millennium AD, two previously little-known boron- and alumina-rich compositional groups emerge. These glass groups, thought to be regionally produced, dominate glass compositions in Pergamon during the mid-to late Byzantine and Islamic periods, indicating a major shift in glass supply and a fragmentation of the economy into more regional units. Plant-ash glass, from the 9th century AD replacing mineral natron glass in the Levant, plays only a minor role in Byzantine and Islamic Pergamon.

Biomass gasification is more suitable than combustion for Combined Heat and Power (CHP) applications. In this field, fluidized bed reactor technology ensures good mixing of continuously fed fuel and provides homogeneous temperature distribution in the reactor. The aim of the gasification is to produce clean syngas, thus it is important to investigate the influence of various operating conditions on the property of gas products and tar evolution. Usually, temperature and catalytic bed composition are the most studied parameters. In spite of the advantages of fluidized beds, biomass gasification suffers from technical problems such as slagging and fouling due to the high ash content and the formation of low melting point compounds and eutectic composition. The understanding of bed agglomeration requires the investigation of natural phases of biomass mineral matter and bed material. Due to the abundance of ash in biomass and its low degree of crystallization, supplementary methods have to be used beside XRD, LA-ICP-MS and SEM–EDX analysis to characterise interactions between ashes and fluidized bed material.

The medieval iron market in Ariege (French Pyrenees) is characterised by its complexity leading to many questions regarding the ore used in relation to the artefacts encountered in archaeological settings. Despite the conclusive study of the treaty that regulated iron vs. coal exchanges from the 14th to the 19th c. by Verna et al., many questions remain unanswered concerning provenance and circulation of ores and products. Based on a combination of trace elemental analysis and multivariate statistical methods (discriminant analysis, hierarchical clustering analysis), we propose to follow an elemental-based signature from ore to artefacts, suited to the direct iron process, to clarify provenance hypotheses. We define the chemical signature of the Ariege area and compare it to that of slag inclusions in artefacts uncovered in several main archaeological sites from the Ariege area but also outside of this region. The results from this study are consistent with prior knowledge from historical sources. In the Ariege region, results highlight the multiple origins of products encountered at Montreal-de-Sos, a site close to known trade routes, whereas the isolated Castel-Minier site primarily contained objects from local ores and most objects retrieved from the Mirabat castle (Couserans) are coming from outside Ariege, possibly an indirect consequence from the exchange treaty. The presence of pins made of Ariegean ores is also demonstrated in the far more distant Capestang collegiate (near Narbonne, outside Ariege). This opens the way to finer studies in the politico-economical control of the iron supply for the building of medieval monuments in Southern France.

The Golludag obsidian lava flow system is relatively complex. More than ten different obsidian outcrops and knapping workshops have been identified around this volcano. Their importance for long and short distances obsidian supply has already been demonstrated. One of the main problem encountered when studying the Golludag obsidian flows, is the great chemical similarity of some of them. The use of the geochemical approach to solve the problems of obsidian trade around the Golludag is therefore insufficient. A multi-disciplinary program joining archaeology, geochemistry and geomorphology, was thus started to understand the relationships between the different obsidian flows and to draw the pattern of the Golludag obsidian trade. Our archaeological and geomorphologic approach will help us to understand which obsidian outcrops were available during the Palaeolithic and Neolithic periods. Also our geomorphologic approach, linked to intensive geochemical analyses, will help us to understand the spatial variability of the geochemistry of the obsidian outcrops. Lithic technology will also give information about the different knapping methods used at the workshops.