Julian Henderson

Twenty-six samples from domestic assemblages of 9th–12th century Córdoba were subjected to electron microprobe analysis. The results reveal two main compositional types. The first, encountered in 13 of the samples, seems to result from the combination of plant ashes with high-impurity sand, and has some contemporary parallels from Syria and Egypt. The second type is a lead–soda–silica glass, encountered in a relatively high proportion of the glasses (11 of the 26 sampled), possibly formed by the addition of lead metal to existing glasses and with very few known parallels. These are among a very small number of results available to date on the chemical composition of glasses from medieval Spain, and the presence of a high proportion of lead–soda–silica glasses is particularly interesting, possibly indicating a technological practice unique to, or originating in, the western Muslim world.

This paper presents the first global results from electron probe microanalysis of glass found in Hittite and early iron age contexts from sites in central Anatolia. The article considers the wide range of compositions discovered and poses the question  whether the glasses were made in Turkey or not.

29 Si magic angle spinning (MAS) NMR spectroscopy is applied for the first time to the structural analysis of ancient glass samples obtained from archaeological excavations. The results show that it is possible to establish the distribution of Si environments in ancient glass by 29 Si MAS NMR, so long as the concentrations of magnetic impurities, such as Mn and Fe oxides, are low. In general good agreement has been obtained with compositions found using electron probe microanalysis. In addition, the 29 Si MAS NMR data reveal structural differences between glasses manufactured at separate ancient sites.

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 K 2 O 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 Al 2 O 3 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.

We have investigated the provenance of highly coloured Roman glass from Italy by determining strontium and neodymium isotope signatures. The results suggest that the main production area was the Levantine coast and that other potential areas are the central-western Mediterranean and possibly Egypt. The Levantine isotopic values are variable, possibly attesting to the existence of sub-zones; they overlap with values from Apulia and Ba-silicata in Italy. Mosaic tesserae and raw glasses have been compared with other isotope values and this suggests that colorant-rich raw materials were added at or near primary production sites. The isotopic signature of one glass cake from a 4th–early 3rd century BCE Sardinian wreck suggests that western Roman production might be rooted in the Phoenicio-Punic tradition. We have observed a mis-match between the five chemical types of later natron glass and the isotopic provenance signatures.

We have investigated the provenance of highly coloured Roman glass from Italy by determining strontium and neodymium isotope signatures. The results suggest that the main production area was the Levantine coast and that other potential areas are the central-western Mediterranean and possibly Egypt. The Levantine isotopic values are variable, possibly attesting to the existence of sub-zones; they overlap with values from Apulia and Ba-silicata in Italy. Mosaic tesserae and raw glasses have been compared with other isotope values and this suggests that colorant-rich raw materials were added at or near primary production sites. The isotopic signature of one glass cake from a 4th–early 3rd century BCE Sardinian wreck suggests that western Roman production might be rooted in the Phoenicio-Punic tradition. We have observed a mis-match between the five chemical types of later natron glass and the isotopic provenance signatures.

This study presents the results of an archaeometrical investigation performed on 75 black glass beads dated to the ninth–fifth century BC coming from Bologna, Cumae, and Pozzuoli (Italy), and Chotin (Slovakia). The analyses of the major, minor, and trace elements—as well as that of Sr and Nd isotopes performed on a selection of samples coming from Bologna—provided evidence for two different production technologies in Iron Age black glass found in Italy (natron glass, probably produced in Egypt) and Slovakia (wood ash glass, probably produced in Europe). In both cases, the glasses derive their black colouration from the high presence of iron (around 12 % FeO), introduced into the glass batches through the intentional choice of dark sands. The production model appears to be small-scale and experimental, characterised by the use of non-sorted raw materials and poorly defined formu-lae, producing glass with a high chemical variability. The wood ash technology appears to have dropped out of use in Europe until the Medieval period, while natron production spread quickly, becoming predominant throughout the Mediterranean.

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 K 2 O 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 Al 2 O 3 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.

In the present study, 53 glass fragments from core-formed vessels and 3 glass beads are investigated using SEM/ EDX, EPMA and LA-ICP-MS. All samples were excavated in the Latin settlement of Satricum in central west Italy and apart from two, were found in the so-called fourth–third c. BC Hellenistic Votive deposit, also known as Votive Deposit III, discovered in front of the sanctuary of Mater Matuta on top of the acropolis. The analytical results indicate that the glass from Satricum is a typical soda-lime-silica type with natron used as a flux. Its chemical compositions display a relatively low com-positional variation. Small differences in the concentrations of major and minor oxides (SiO 2 , Al 2 O 3 , CaO and Fe 2 O 3) and in trace elements (Sr, Zr and Nd) between individual samples suggest the use of different types of raw materials, especially sand. In turn, this suggests that the glass derived from more than one glass making centre. The combined investigation of colourants (Co, Cu and Mn) reinforces and confirms the idea that glass from Satricum was made using different manufacturing traditions during the Hellenistic period.

This is the first broad survey using major, minor and trace element analyses of 8th–15th AD plant ash glass from the Middle East across a 2000 mile area stretching from Egypt to northern Iran. This was part of the ancient Silk Road that extended from the Middle East, through central Asia to China. Up to now, some compositional distinctions have been identified for such glasses mainly using major and minor element oxides and radiogenic isotopes. Our new trace element characterisation is for such glasses, mainly found in selected cosmopolitan hubs, including one where there is archaeological evidence for primary glass making. It provides not only far clearer provenance definitions for regional centres of production, in the Levant, northern Syria and in Iraq and Iran, but also for sub-regional zones of production. This fingerprinting is provided by trace elements associated with the primary glass making raw materials used: ashed halophytic plants and sands. Even more surprising is a correlation between some of the sub-regional production hubs and the types of glass vessels with diagnostic decoration apparently manufactured in or near the cosmopolitan hubs where the glass was found such as colourless cut and engraved vessels (in Iraq and Iran) and trail-decorated vessels (in the Levant). This therefore provides evidence for centres of specialisation. Our trace element characterisation provides a new way of defining the Silk Road by characterising the glass that was traded or exchanged along it. Taken together this data provides a new decentralised model for ancient glass production.

To continue the enquiry into strontium isotope compositions in southern Chinese glazes, this study determines the strontium isotope compositions of porcelain glazes of Dehua 'Blanc De Chine' porcelain and blue-and-white porcelain, and Tai Po blue-and-white porcelain. Mixing lines are displayed in the strontium isotope compositions of the Dehua glazes, suggesting that raw materials of different natures were used to make the two glazes. By referring to the historical resources, a high-calcium plant ash and a mixture of limestone and high-silica ash can be suggested as the fluxes used in the recipes for 'Blanc De Chine' glaze and blue-and-white glaze respectively. The strontium isotope compositions of Tai Po blue-and-white porcelain glazes separate into two groups, suggesting that different recipes were used to make the same glaze. The group A includes too few samples to allow an identification of the raw materials used, while the strontium isotope compositions of group B samples suggest that a high-calcium plant ash was added as the flux.

This paper explores the history of the Chinese porcelain trade in Oman with the aim of gauging the impact of these wares on Oman’s religious architecture. The large quantities of porcelain surface finds from the interior and the comparatively unusual reliance on them for the decoration of prayer niches, in the presence of equally valuable wares from Persia and elsewhere, suggest an elevated status for these objects, which is not necessarily a product of their immediate monetary value. Chemical and stylistic analyses were carried out to determine the dates and provenance of the ceramics studied, with the aim of gaining a better understanding of their introduction into the Omani market and their relation to religious design schemes.

Keywords: Omani decorated mihrab, Chinese porcelain in Oman, Manah, Sinaw, Ibadism in Oman

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has been used, for the first time, for the characterization of opaque ancient glasses. Isotope-specific chemical imaging with sub-micron resolution enabled the separate analysis of opacifiying inclusions and the surrounding glass matrix. Phase identification has been demonstrated and quantification of the matrix composition has been investigated by use of Corning Glass Standard B as a model. Trace element detection limits are typically in the range 0.5–5.0 ppm atomic—in favourable cases down to 0.01 ppm. For the analysis of inclusions in particular, this has the potential to provide new information of use in establishing provenance and trade routes by ‘fingerprinting’ as well as the investigation of manufacturing techniques, as demonstrated by comparisons between glasses and with EDX data from the same samples.

This article presents and discusses the results of chemical analyses of glass jewelry and frit from two Mycenaean sites in mainland Greece: the palatial center of Thebes in Boeotia and the cemetery at Elateia in northeastern Phokis. The analyzed glass dates from the beginning of the Late Helladic IIIA period (about 1425/1390–1390/1370 B.C.) to the Early Protogeometric period (about 1000/950 B.C.) Through the chemical analysis of Late Bronze Age Aegean glass, to make a contribution to models of Aegean glass production, encompassing its origins, technology, and cultural attributes. More specifically, we hope that the raw materials used to make the glass will produce distinctive compositional groups. In addition, the results can be used to trace chronological changes in glass technology, to highlight inter- or intra-site variations in glass compositions, and to compare Mycenaean glass compositions with contemporaneous glass from the Near East, Egypt, and the western Mediterranean. The question of whether this industry involved the primary production of glass or consisted of glassworking alone can also be addressed using technological and scientific techniques. In sum, having produced the largest data set of Mycenaean glass compositions available to date, the analytical results from Thebes and Elateia will be used as a means of defining Mycenaean glass technology within the broader context of glass technology in the Late Bronze Age Mediterranean.