The Production and Circulation of Carthaginian Glass Under the Rule of the Romans and the Vandals (Fourth to Sixth Century ad): A Chemical Investigation

Fifty‐seven glass samples from Carthage dating to the fourth to sixth century ad were analysed using the electron microprobe. The results show that these samples are all soda–lime–silica glass. Their MgO and K₂O values, which are below 1.5%, suggest that they were made from natron, a flux that was widely used during the Roman period. The major and minor elements show that these samples can be divided into four groups, three of which correspond to the late Roman period glass groups that were found throughout the Roman Empire: Levantine I, and ‘weak’ and ‘strong’ HIMT. Of particular interest is our Group 2, which is technologically and compositionally similar to HIMT glass and the CaO and Al₂O₃ values of which are similar to those of Levantine I. Glass of similar composition has been reported by several authors and is predominantly found dating from the late fifth to seventh century. This could represent a ‘new’ glass group; therefore further study is needed to determine its origin. Also, this study suggests that the Vandal invasion in North Africa did not disrupt the glass trade between Carthage and the Levantine coast.     

Sustainability transformations in the balance: exploring Swedish initiatives challenging the corporate food regime

ABSTRACT

This paper explores to what extent organic initiatives that go beyond mainstream organic (so-called Organic 3.0) can challenge the corporate food regime and how they can push the food system towards sustainability transformations. We depart from the assumption that individual initiatives may differ in their potential to influence the corporate food regime and that this potential can be assessed by examining traits linked to reformist, progressive or radical food regime/food movement trends that they may possess. Rather than establishing a dichotomy between niche and food regime or categorizing Organic 3.0 initiatives within one of these trends, we explore the nuances in niche–regime relationships within the food system from a multi-level perspective, using the cases of two Organic 3.0 initiatives in Sweden. The results show that relations between these initiatives and the food regime share key characteristics, but also differ in important respects. While a reformist strategy facilitates niche growth, progressive and radical approaches are more likely to challenge the regime. The choice of approach in both cases involves trade-offs between growth and organic values. We conclude that one of the primary roles of Organic 3.0 initiatives may be to illustrate the viability of alternative models.     

Removal of natural organic dyes from wool–implications for ancient textile provenance studies

Ancient wool textiles recovered from archaeological sites are in many cases originally dyed with natural organic dyestuffs from vegetable sources. These include among others woad (Isatis tinctoria L.), weld (Reseda luteola L.), and madder (Rubia tinctorum L.). These dyestuffs could be a threat to the use of the strontium isotopic system as a tracer for provenance studies of ancient wool, because they could potentially contaminate the signature of the textile's raw material. We present a novel method which allows for efficient removal of organic dyestuffs in wool prior to strontium isotopic analysis. Our method is based on an oxidative release of the dyestuff constituents by ammonium peroxodisulfate [(NH₄)₂S₂O₈] solution, combined with hydrofluoric acid (HF) that has shown to effectively remove/dissolve adhering dust micro-particles. Our multi-analytical results show that such a pretreatment is capable of removing >98% of the originally present organic dyestuffs without significantly destroying the wool structure. The strontium isotopic ratios of the residual wool fraction after the application of the pretreatment are sensitive to the origin and, therefore, can be used as tracers for the provenance of the raw material. We propose to apply this method to ancient wool textiles in which positive identification of organic dyestuff constituents by High Performance Liquid Chromatography (HPLC) was made.     

Trade centres and commercial routes in the Arabian Gulf: Post-Hellenistic discoveries at Dibba, Sharjah, United Arab Emirates

The excavation of a tomb of the Roman-Parthian period in Dibba Al Hisn, Sharjah, is discussed. The contents provide evidence of far-ranging trade contacts extending from the Mediterranean to India.     

Advanced design of Chinese traditional materials for the conservation of historic stone buildings

The conservation of historic stone buildings and sculptures is recently receiving growing attention and becoming a focus of research because of rapid changes in weather conditions (pollution, acid rain, etc.). Presently, techniques for stone conservation primarily involve the use of organic coating treatments, but their side effects have been recognized. In contrast, some traditional materials used in historic stone buildings function well for thousands of years. In this paper, we report our research on the reasons why traditional protective materials can provide an unexpected long-term protection. First, calcium carbonate was prepared according to a formula for making Chinese traditional consolidating materials, and its structure and morphology were examined by different instruments. Second, the reinforcing effectiveness of the prepared CaCO₃ powders was tested and analyzed by investigating its surface characteristics. The experimental results reveal that a biocontrolled process occurs, in which an organic template can induce the precipitation of a mineral structure, which in turn results in a great improvement in the conservation of the historic stone buildings protected by these traditional protective materials. This provides a contribution toward the development of new researches on biocontrolled processes and on some protective materials with excellent performance through biocontrolled synthesis.     

XRF analysis of glass beads from the Mycenaean palace of Nestor at Pylos,Peloponnesus, Greece: new insight into the LBA glass trade

In recent years there has been a growing interest in Mycenaean glass among archaeologists and scientists. Scholars have traditionally thought that all Mycenaean glass was imported either in finished form or as ingots and simply shaped or worked at the Mycenaean sites. Chemical studies of other Mycenaean glass (50 and 43) support the hypothesis that glass was imported into Mycenaean Greece, but there is also indication for glass production in mainland Greece at the palace of Thebes (Nikita and Henderson, 2006). There is no evidence for glass making or working at the Palace of Pylos, yet there is an abundance of glass beads there. The aim of this paper is to identify the technology and source for the glass of these beads and thus to ascertain how Pylos was connected to the broader Mycenaean and Mediterranean economies. The composition of the glasses was determined by means of portable XRF analysis and compared to that of other Late Bronze Age glasses from Egypt, Mesopotamia and mainland Greece. Four blue beads coloured with cobalt and one blue bead coloured with copper have Ti and Zr compositions consistent with an Egyptian origin of manufacture while five other beads show Ti and Zr concentrations consistent with a Mesopotamian origin (Shortland et al., 2007). Based on the dearth of Egyptian and Mesopotamian imports in Pylos, the presented data support the hypothesis that Pylos was receiving via internal Greek trade routes foreign-produced glass, which may have been worked abroad or in Greece.     

Glass Beads from 15th–17th Century CE Jar Burial Sites in Cambodia's Cardamom Mountains

A total of 74 glass beads, included as grave goods in 15th–17th century CE jar burials from Cambodia's Cardamom Mountains, were analysed using laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS). Several glass types were identified, including two subtypes of high‐alumina mineral soda glass, and lead–potash glass. The final glass type represents a newly discovered and previously unidentified type of high‐alumina soda glass, with high magnesia (m‐Na–Al Mg>). This study represents the first glass data from the mid‐second millennium CE from Cambodia and sheds light on the multiple long‐distance maritime exchange networks in which the upland people buried in the jars were participating.     

Analyses of Early Medieval Stained Window Glass From the Monastery of Baume‐Les‐Messieurs (Jura,France)

The collection of early medieval window glass found in the abbey of Baume‐les‐Messieurs (Jura, France) is exceptional because it dates to the end of the eighth century, and due to the number of fragments as well as their state of conservation. Different colours and forms have been identified. These pieces are a rare opportunity to address the glass craft, its recipes and techniques for a phase of its history that has remained little known. Analyses in PIXE–PIGE prove that, in addition to fragments from two soda glass items, the pieces are made from wood‐ash glass. Most of them probably came from the same production and the raw material is present in the region. At this early stage of wood‐ash glass production, the glassmakers had mastered the glass as well as the colour processes.     

Holocene land-use evolution and associated soil erosion in the French Prealps inferred from Lake Paladru sediments and archaeological evidences

A source-to-sink multi-proxy approach has been performed within Lake Paladru (492 m a.s.l., French Prealps) catchment and a 6-m long sediment sequence retrieved from the central lacustrine basin. The combination of minerogenic signal, specific organic markers of autochthonous and allochthonous supply and archaeological data allows the reconstruction of a continuous record of past human disturbances. Over the last 10,000 years, the lacustrine sedimentation was dominated by autochthonous carbonates and the watershed was mostly forest-covered. However, seven phases of higher accumulation rate, soil erosion, algal productivity and landscape disturbances have been identified and dated from 8400 to 7900, 6000 to 4800, 4500 to 3200, 2700 to 2050 cal BP as well as AD 350–850, AD 1250–1850 and after AD 1970. Before 5200 cal BP, soil erosion is interpreted as resulting from climatic deterioration phases towards cooler and wetter conditions. During the Mid-Late Holocene period, erosion fluxes and landscape disturbances are always associated with prehistorical and historical human activities and amplified by climatic oscillations. Such changes in human land-used led to increasing minerogenic supply and nutrients loading that affected lacustrine trophic levels, especially during the last 1600 years. In addition, organic and molecular markers document previously unknown human settlements around Lake Paladru during the Bronze and the Iron Ages.     

Potash - a key raw material of glass batch for Bohemian glasses from 14th-17th centuries?

The aim of this work is to verify or refute hypothesis of existence of basic/universal glass batch: quartz sand: potash: limestone, at a ratio of 2: 1: 1 used in Bohemian glass production since the middle ages onwards and to simulate the preparation of a potassium glass type with the composition used in medieval Bohemia. The chemical composition of Bohemian glass, which incorporated in the proposed glass batch for glassmaking on a laboratory scale, was evaluated by (a) findings directly related to glassmaking (samples from glasswork in Moldava dating back to the 15th century) and (b) information from publications.Experimentally produced glasses for the present paper were prepared from raw materials such as ash, leached ash, potash, limestone and quartz sand. The plant raw materials (spruce, beech and bracken ashes, raw and refined potash) were treated and prepared by methods similar to the production procedures used in the pre-industrial era.The main contrast was found in the CaO/K₂O weight ratio, which was determined in glasses that were characteristic of given periods. While this ratio was often below 1 in glasses of the 15th century, it reached values above 1 in glasses at the turn of the 16th-17th centuries. This result may indicate that the composition of the glass batch had changed.The results of the present study reject the current scholarly work dealing with glass batch composition during the 14th-17th centuries and confirm that glass produced in some Bohemian medieval glassworks could have been melted from a batch that included plant ash, making the use of limestone unnecessary. The traditional suggestion of the exact ratios of raw materials, often cited in historical literature, seems to be impossible. The glassmakers had to react to the variable composition of the raw materials, especially plant ash.