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Sb was frequently used as a raw material, both in ancient glass-making (as an opacifier and decolouriser) and metallurgy (either as an alloying element or as a pure metal). Despite this ubiquity, antimony production has only occasionally been studied and questions concerning its provenance are still not satisfactorily answered. This study evaluates the suitability of Sb isotope analysis for provenance determination purposes, as experiments under lab conditions have revealed fractionation occurring during redox processes in oxidising stibnites and in making opacified glasses. The results of this paper help to evaluate the possible influence of the pyrotechnological processes on the antimony isotope composition of glass artefacts. This paper focuses on the Caucasus as case study by applying mineralogical, geochemical and isotopic analysis to Georgian ores (mainly from the Racha-Lechkumi district) and Late Bronze Age (LBA; 15th–10th century BCE) metallic Sb objects found at the sites of Brili and Chalpiragorebi.

Substantial databases of elemental and isotopic analyses of ancient glass exist and are used to investigate raw material origin, trade, exchange, and processes such as mixing and recycling. However, the chemistry of archaeological glass may be challenging to the untrained. The paper provides structured information on the origin of chemical elements and their isotopes in ancient glass. It details some of the functions of individual elements in the glass and from which raw material(s) or process(es) they originate. [ABSTRACT FROM AUTHOR]

This paper re‐analyses a considerable corpus of glass from the Late Bronze Age site of Nuzi, found near Kirkuk in Iraq. SEM–WDS and Sr and Nd isotopic analysis were applied, in addition to cataloguing the glass. The work showed that the glass technology at Nuzi was subtly different from contemporary Egyptian sites, using different ways of opacifying and working glass. At least two, perhaps three, Near Eastern production sites are postulated. The range of glass colours and the skill of their application at Nuzi was perhaps not on a par with the Egyptian sites. This led to a reconsideration and review of the accepted wisdom that the Near East is the source of the innovation that is glass‐making. This opinion is based on limited textual and iconographic sources and is dominated by an erroneous early date for a very developed Nuzi glass industry along with a few finds of glass vessels in early contexts. Some of this evidence has now been at least questioned, suggesting that glass‐making in Egypt, at least as early as the middle of the 15th century bc, and probably earlier, is no later than that in the Near East. It is argued that it is far from clear that the Near East was the source of the innovation and that a more cautious approach would better fit the evidence. [ABSTRACT FROM AUTHOR]

Glass objects from Pydna and Methoni in modern-day Greece, dated to the eighth to fourth century BC, were chemically investigated. The combined use of multiple analytical techniques allowed the elemental and isotopic characterization of these polychrome and colourless glass artefacts in order to examine their provenance. All fragments were found to be soda-lime-silica natron-based glass produced from a rather pure silica-rich sand containing sea shells, and mixed with natron possibly coming from more than one source. Based on the strontium and neodymium isotopic signatures, most glass artefacts likely derive from a Syro-Palestinian production site although the exact location is unknown. Also the oxygen isotopic signature of most of the samples suggests the manufacturing of the artefacts from raw materials with a primary origin along the Syro-Palestinian coast. Nevertheless, the use of particular raw materials cannot be excluded for some artefacts, as some samples show enriched δ 18 O values pointing to a different glassmaking tradition. [ABSTRACT FROM AUTHOR]

The practice of re-melting glass was well known, certainly from the Roman period onwards. This can be seen not only in ancient literary evidence but also in the archaeological evidence, collections of broken glass have been found in, for example, Pompeii (79 AD) and the Iulia Felix shipwreck (Third century AD). Elevated levels of certain transition metals in archaeological glasses are interpreted as indications of the mixing and/or recycling of different glasses. Assumptions have been made that all glasses could be recycled, but to what extent are these valid? Why does the evidence for the recycling of glass only occur from the Roman period onwards? From the middle of the First millennium BC to the Ninth century AD, natron glass was the predominant glass type in the Mediterranean and Europe, however, plant ash glass was still in use in some areas. To test the effects on the final product of mixing different composition glass types, experimental glasses were made by mixing varying quantities of replica plant ash glass, replica natron glass, and a modern glass. At low temperatures crystalline material formed in the products containing replica plant ash glass. As the plant ash glass content increased, so too did the amount of crystalline material produced. This is due to a combination of the glass compositions and the firing temperature. It appears that natron type glass can be more easily recycled at lower temperatures, although, if a high enough temperature is used then most glass types can be recycled. Early furnace technology, i.e. the vertical heating chamber furnace, may not have been able to achieve these high temperatures, hence the widespread practice of recycling did not begin until after the invention of glassblowing which required a change in the furnace technology to the use of a horizontal heating chamber furnace. [ABSTRACT FROM AUTHOR]

Previous research has shown that Iznik glazes are characterized by low potash and magnesia contents. It was therefore suggested that the flux used was either a purified plant ash or some unidentified mineral source of soda. More recently, as a result of the detection of small, but significant, amounts of boron and lithium in Byzantine glasses from western Turkey, which also exhibit low potash and magnesia contents, it has been suggested that the source of the flux used was a soda-rich evaporite associated in some way with the extensive borax deposits in the region. LA-ICP-MS has been used to establish that Iznik glazes also contain similarly small amounts of boron and lithium. The Na/K, Na/Mg, Na/Ca and Na/B ratios for these Iznik glazes are shown to be comparable to the equivalent ratios calculated from published data for waters from a range of Na-HCO3 type hot springs in western Turkey, with the closest match being to the hot springs around Afyon- Gazligöl, which is consistent with documentary evidence. It is therefore proposed that the soda-rich salts produced by evaporating water from these springs to dryness would have provided the flux required for the production of Iznik glazes and high-boron Byzantine glasses. [ABSTRACT FROM AUTHOR]

In this study, the use of trace elements as a provenance indicator for Roman natron glass is evaluated. Suitable glass‐making sand raw materials are analysed for their trace elemental composition and compared to glass from known production centres. It is shown that the combined use of Nd isotopic and trace element analysis can be efficient for the provenancing of Roman glass. Trace elements associated with (de)colourants of glass are only present in small concentrations in glass‐making sands. Background levels introduced to the glass by the sand raw material are defined and a lower threshold for the concentrations influenced by recycling is determined. [ABSTRACT FROM AUTHOR]

A multidisciplinary study of a unique group of Late Bronze Age (LBA) ceremonial glass axe heads and other artefacts shows that these are the first significant group of glasses coloured with cobalt to be identified from the Near East. The axes were excavated from the site of Nippur, in present-day Iraq. Several are incised with the names of three kings, which dates the material to the 14th-13th centuries bc. Analysis by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) indicates that the glass had high magnesia (MgO) and potash (K2O) associated with a plant-ash flux and was coloured blue by copper or a combination of copper and cobalt. These glasses are similar, but not identical, in major element composition to blue-coloured glasses manufactured in ancient Egypt and elsewhere in Mesopotamia in the same period. However, the Nippur cobalt- and copper-coloured glasses exhibit significantly different trace elemental compositions compared to Egyptian glass coloured with cobalt, showing that the ancient Near Eastern glassmakers had clearly identified and utilized a distinctive cobalt ore source for the colouring of this glass. Since it was previously thought that the only cobalt ores exploited in the LBA were exclusively of Egyptian origin, this new finding provides new insights on the origins of glass and how it was traded during the Bronze Age period. [ABSTRACT FROM AUTHOR]

This paper presents oxygen, strontium and neodymium isotopic analysis from a series of Late Bronze Age glasses from Egypt and Mesopotamia. It was found that oxygen and neodymium isotopes alone cannot readily distinguish between glasses from the various sites. However, combined Sr and Nd isotope analysis separate the data into three groups: an Egyptian group with relatively low Sr and Nd ratios; a Late Bronze Age (LBA) Nuzi group with high Sr and low Nd ratios; and an intermediate Sr and high Nd ratio grouping of glasses from Tell Brak. These findings suggest that most of the glass from Nuzi and Tell Brak had different raw materials and hence the glass was probably produced at different manufacturing sites. However, one glass ingot found at Tell Brak (TB1) appears to have Nuzi-type Sr–Nd characteristics. This is the first positive identification of multiple production sites in LBA Mesopotamia and an exceptional example of a glass that may have been exchanged from one LBA site to another. [ABSTRACT FROM AUTHOR]

Abstract: In Roman and Byzantine times, natron glass was traded throughout the known world in the form of chunks. Production centers of such raw glass, active from the 4th to 8th century AD, were identified in Egypt and Syro-Palestine. However, early Roman primary glass units remain unknown from excavation or scientific analysis. The ancient author Pliny described in 70 AD that besides Egyptian and Levantine resources, also raw materials from Italy and the Gallic and Spanish provinces were used in glass making. In this study, the primary provenance of 1st–3rd century AD natron vessel glass is investigated. The use of combined Sr and Nd isotopic analysis allows the distinguishing and characterizing of different sand raw materials used for primary glass production. The isotope data obtained from the glass samples are compared to the signatures of primary glass from known production centers in the eastern Mediterranean and a number of sand samples from the regions described by Pliny the Elder as possible sources of primary glass. Eastern Mediterranean primary glass has a Nile dominated Mediterranean Nd signature (higher than −6.0 ɛ Nd), while glass with a primary production location in the western Mediterranean or north-western Europe should have a different Nd signature (lower than −7.0 ɛ Nd). Most Roman glass has a homogeneous 87Sr/86Sr signature close to the modern sea water composition, likely caused by the (intentional) use of shell as glass raw material. In this way, strontium and neodymium isotopes now prove that Pliny''s writings were correct: primary glass production was not exclusive to the Levant or Egypt in early Roman days, and factories of raw glass in the Western Roman Empire will have been at play. [Copyright &y& Elsevier]

Abstract: The secondary production (working) of glass from imperial to early Byzantine times has been proven at the ancient city of Sagalassos (SW Turkey) by the existence of glass chunks, fuel ash slag and kiln fragments related to glass processing. It had been previously suggested that local green glass might have been recycled from two other locally found glass types (blue glass vessels and chunks and HIMT glass chunks). This paper provides analytical evidence for the recycling of glass next to the use of imported raw glass. The heterogeneous lead isotopic composition of the green and HIMT vessel glass at Sagalassos, with as end members on the one hand the isotopic composition of local blue glass vessels and chunks and on the other hand that of the HIMT glass chunks, could indicate the production of ‘recycled’ glass, although heterogeneous raw materials could have been used. However, the use of Sr-mixing lines confirms local recycling. It is clear that the Sr in the green and HIMT vessels is a mixture of the Sr in the aforementioned end members. It cannot be proved whether the green ‘recycled’ glass was produced from a mixture of chunks alone, or from a mixture of cullet and chunks. Suggestions are made towards the possible origin of the raw materials for the blue and HIMT glass on the basis of Sr isotopic signatures and absolute Sr contents in the glass. [Copyright &y& Elsevier]

Abstract: The finding of glass chunks together with fuel ash slag and kiln fragments related to glass processing strongly suggests local secondary production (working) of glass at Sagalassos (SW Turkey) from imperial to early Byzantine times. Chemical evidence shows that different silica raw materials were used in imperial and early Byzantine times for blue and green glass found locally. Colourless glass shows no clear difference in chemical composition and hence in silica raw materials between late Roman and early Byzantine times. Locally found early Byzantine yellow-green glass and chunks correspond to the previously defined Byzantine HIMT glass type. The chemical composition of the glass chunks found, identical to that of the contemporary glass of the same colour, strongly indicates that these chunks were used for the manufacture of early Byzantine green, colourless and yellow-green glass at Sagalassos. The homogenous lead isotopic composition of the chronological groups of blue glass, suggests the use of two distinct but homogenous silica raw materials for the manufacture of this glass. In view of this homogeneity, it is likely that contemporary blue glass was produced at a single location. The linear trend of the heterogeneous lead isotopic composition of the green and colourless glass is a strong indication of recycling effects in the glass composition. The end members of this trend are formed by the isotopic composition of the blue glass on the one hand, and of the yellow-green (HIMT) glass on the other hand. The heterogeneous lead isotopic composition of the yellow-green glass at Sagalassos is probably the result of recycling of this glass, reflecting mixtures of the original lead isotopic signatures of the broken glass and the original HIMT glass chunks. It should be noted that the two main raw materials for primary glass production (silica and soda) were available on the territory of Sagalassos. Moreover, the lead isotopic composition of quartz pebbles sampled from the artisanal quarter of Sagalassos, is similar to that of the local blue glass. [Copyright &y& Elsevier]

Abstract: The origins of raw glass used to fashion Mycenaean beads were explored using trace elements analyzed by laser ablation ICP-TOFMS. The use of this minimally destructive technique for the in-situ analysis of these beads was ideal given that the material is exceedingly rare and thus too sensitive to make use of traditional micro-sampling (e.g., by scalpel). A wide range of trace elements were measured to compare these Greek glasses to other Late Bronze Age glass coming from Egypt and Mesopotamia. Of the eleven beads analyzed, four blue glasses colored with cobalt and two blue/green glasses colored with copper have trace element compositions consistent with an Egyptian origin of manufacture. The other five of the glasses, all colored with copper, were found to conform to the composition of Mesopotamian glass. These data are the first to demonstrate direct and clear evidence for the trade of raw glass to the Mycenaean states. [Copyright &y& Elsevier]