Naturally occurring glass, especially the volcanic glass obsidian, has been used by many Stone Age societies across the globe for the production of sharp cutting tools and, due to its limited source areas, was extensively traded. But in general, archaeological evidence suggests that the first true glass was made in coastal north Syria, Mesopotamia or ancient Egypt. Because of Egypt's favorable environment for preservation, the majority of well-studied early glass is found there, although some of this is likely to have been imported. The earliest known glass objects, of the mid-third millennium BCE, were beads, perhaps initially created as accidental by-products of metal-working (slags) or during the production of faience, a pre-glass vitreous material made by a process similar to glazing.[n 1]
Threads of thin glass of different colors made with admixtures of oxides were subsequently wound around these to create patterns, which could be drawn into festoons by using metal raking tools. The vessel would then be rolled smooth (marvered) on a slab in order to press the decorative threads into its body. Handles and feet were applied separately. The rod was subsequently allowed to cool as the glass slowly annealed and was eventually removed from the center of the vessel, after which the core material was scraped out. Glass shapes for inlays were also often created in moulds. Much of early glass production, however, relied on grinding techniques borrowed from stone working. This meant that the glass was ground and carved in a cold state.
Texts such as the Shatapatha Brahmana and Vinaya Pitaka mention glass, implying they could have been known in India during the early first millennium BCE. Glass objects have also been found at Beed, Sirkap and Sirsukh, all dating to around the 5th century BCE. However, the first unmistakable evidence for widespread glass usage comes from the ruins of Taxila (3rd century BEC), where bangles, beads, small vessels, and tiles were discovered in large quantities. These glassmaking techniques may have been transmitted from cultures in Western Asia.
Glassmaking developed later in China compared to cultures in Mesopotamia, Egypt and India. Imported glass objects first reached China during the late Spring and Autumn period (early 5th century BCE), in the form of polychrome eye beads. These imports created the impetus for the production of indigenous glass beads.
The majority of complete vessels and assemblages of beads come from the excavations of early Anglo-Saxon cemeteries, but a change in burial rites in the late 7th century affected the recovery of glass, as Christian Anglo-Saxons were buried with fewer grave goods, and glass is rarely found. From the late 7th century onwards, window glass is found more frequently. This is directly related to the introduction of Christianity and the construction of churches and monasteries. There are a few Anglo-Saxon ecclesiastical literary sources that mention the production and use of glass, although these relate to window glass used in ecclesiastical buildings. Glass was also used by the Anglo-Saxons in their jewelry, both as enamel or as cut glass insets.
An early advance in automating glass manufacturing was patented in 1848 by the engineer Henry Bessemer. His system produced a continuous ribbon of flat glass by forming the ribbon between rollers. This was an expensive process, as the surfaces of the glass needed polishing and was later abandoned by its sponsor, Robert Lucas Chance of Chance Brothers, as unviable. Bessemer also introduced an early form of \"Float Glass\" in 1843, which involved pouring glass onto liquid tin.
This chapter covers nearly three millennia of glassmaking in Egypt, from the beginning of the Late Bronze Age at around 1500 BC up to the beginning of the second millennium AD. This period saw several major changes in the material composition as well as the social meaning of glass, illustrated in our overview by case studies done on glass from Egypt. For much of the Late Bronze Age, and again during the first millennium AD, there is a very significant sea-borne flow of glass from Egypt to the north, providing much of Europe with glass. In contrast, we argue that there is relatively little material interaction and exchange of glass with the Levant to the east, a region which had its own large glass production centres for much of this period. We hope that by looking west and south we can see whether there was a stronger integration of Egypt and its glass industry as part of a wider land-based exchange network. For convenience, the chapter covers the evidence separately for primary glass making and for glass use, respectively, and within these two sections we structure it by broad blocks of time.
Earlier studies comparing manganese glass produced in the Levant and Alexandrian glass of inconclusive origin had failed to differentiate the samples because they contained similar ratios of the isotopes strontium and neodymium, the researchers write in the journal Scientific Reports. To avoid this issue, Barfod and her colleagues decided to look into the relative ratios of isotopes of the element hafnium.
The ancient glass industry changed dramatically towards the end of the first millennium. The Roman glassmaking tradition of mineral soda glass was increasingly supplanted by the use of plant ash as the main fluxing agent at the turn of the ninth century CE. Defining primary production groups of plant ash glass has been a challenge due to the high variability of raw materials and the smaller scale of production. Islamic Glass in the Making advocates a large-scale archaeometric approach to the history of Islamic glassmaking to trace the developments in the production, trade and consumption of vitreous materials between the eighth and twelfth centuries and to separate the norm from the exception. It proposes compositional discriminants to distinguish regional production groups, and provides insights into the organisation of the glass industry and commerce during the early Islamic period. The interdisciplinary approach leads to a holistic understanding of the development of Islamic glass; assemblages from the early Islamic period in Mesopotamia, Central Asia, Egypt, Greater Syria and Iberia are evaluated, and placed in the larger geopolitical context. In doing so, this book fills a gap in the present literature and advances a large-scale approach to the history of Islamic glass.
\"We made a systematic study (employing INAA, microprobe and mass spectrometry techniques) of several varieties of LDG and locally associated sand and sandstone to provide insight into the nature and formation of these enigmatic glass fragments . . . \"Our studies suggest that LDG is the product of meteorite impact into quartz-rich surficial eolion and alluvial sand, and perhaps also into quartz-rich sandstone, of the western Desert of Egypt.\" (science-frontiers.com/sf064/sf064g09)
While frits are considered a material distinct from glass, it is thought that in antiquity, glass could only be made by the manufacture of frits as a first step. In fact, the development of glass technology in most ancient cultures probably grew out of frit manufacture, since it is unlikely that early furnaces could reach and sustain temperatures necessary to melt the glass components without the heavy addition of fluxes. As a result, the mixture retained much seed, or air bubbles, and the materials did not melt entirely.
In addition to the deteriorants described above, enamels have been found to also suffer damage due to the raw materials used as colorants. Though in glass making the proportions of silica-alkali-flux and other components could be adjusted to increase the stability of the glass (Davison 2003: 73)], in enamels the balance of the components was altered in order to achieve desired colors. It appears that color took precedence to the stability of the enamel for it has been observed that some enamels began deteriorating soon after their manufacture. Currently throughout collections of the world, enamels are showing differing level of deterioration based upon their color (Drayman-Weisser 2003;Hughes 1987; Smith, et al. 1987). Conservation efforts to understand more clearly the deterioration of enamels has led to investigations of the ions involved in the active deterioration of enamels.
The study begins with two short chapters introducing the previous scholarship (1-10) and the present work's theoretical basis (11-26) before transisting to the core of the work, a series of case studies (27-166). A short conclusion (167-173) and appendix of Augustan chronology (174-175) follow. The core section examines Egyptian material in Augustan Rome grouped into four categories: two Augustan buildings on the Palatine; Augustan coins and monuments elsewhere in the city; three buildings belonging to the Augustan elite; and a selection of precious items including cameo glass, two gems, and a gold ring. While some of these monuments and objects come as no surprise in a study of this topic - such as the House of Augustus or the Pyramid of Caius Cestius - others are a less common addition, such as the Ara Pacis, Forum of Augustus, and cameo glass. This selection, as indeed van Aerde's project as a whole, can be seen in line with the recent movement to take a more holistic view of Egyptian material within the canon of Roman art, rather than artificially isolating the Egyptian elements.  59ce067264