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Robert Brill is an American archaeologist, best known for his work on the chemical analysis of ancient glass. Born in the US in 1929, Brill attended West Side High School in Newark, New Jersey, before going on to study for his B.S. degree at Upsala College (Brill 1993a, Brill 2006, Getty Conservation Institute 2009). Having completed his Ph.D. in physical chemistry at Rutgers University in 1954, Brill returned to Upsala College to teach chemistry. In 1960, he joined the staff of the Corning Museum of Glass as their second research scientist.
Throughout his career at Corning, where a four-year directorship punctuated his time as a research scientist, Brill was a forerunner in the scientific investigation of glass, glazes and colorants, developing and challenging the usefulness of emerging techniques. His pioneering work with the application of lead and oxygen isotope analysis in archaeology led him occasionally to add the investigation of metal objects to his portfolio so that, together, his published works number more than 160 (Brill and Wampler 1967). Perhaps the most famous of these is his Chemical Analyses of Early Glass, a sum of his 39 years of work and now a seminal reference guide in the field (Brill 1999).
Since 1982, Brill has served on the International Commission on Glass. Within this, he founded TC17, the technical committee for the Archaeometry of Glass, which lists among its aims the ‘promotion of collaboration among glass specialists in widely separated countries’ and the stimulation and encouragement of glass scientists ‘in developing countries’ (Archaeometry of Glass 2005). His internationalism is aptly demonstrated by his study of glasses from around the world, with his attentions most recently being focused on those from the Silk Road. It seems he was attracted by the lack of previous study and the need for further development in the field. Seeing a disparity between contemporary knowledge of glasses from the western world and those from East Asia, Brill was keen to add insight to a hitherto unexploited field and, as such, has gone on to contribute a great deal to Silk Road studies (Brill 1993b).
The 1960s saw Brill beginning to develop the analytical techniques that would define the early years of his career at Corning, and yet the scope of his interest within glass remained vast. Indeed, 1961 saw Brill pen a letter to Nature with a colleague, that was a ‘bombshell’, according to Newton, in the field of glass-dating (1971, 3). Here Brill suggested that the rather enigmatic weathering crust found to form on buried glass objects over time could be used to date the object in a method rather similar to dendrochronology, using the separate layers of the shiny lamination (Brill 1961, Brill and Hood 1961, Newton 1971). Whilst in dendrochronology the tree-rings account simply for the tree's annual growth, in the weathering crust on glass Brill suggested the accumulation of a layer of laminate might respond to some kind of annual event of climatic change (Brill 1961). Unfortunately, despite the examples of the method's successful applications provided by Brill, such as the almost accurate count of 156 layers on a bottle-base from the York River submerged in 1781 and excavated in 1935, the technique largely failed to convince and did not see widespread adoption (Brill 1961, Newton 1971).
The most important of these techniques would prove to be Brill's pioneering application of lead isotope analysis, hitherto used only in geology, to archaeological objects. Brill first presented this idea at the 1965 Seminar in Examination of Works of Art, held at the Museum of Fine Arts Boston, but the first widely published account of the method seems to be Brill and Wampler's 1967 article in the American Journal of Archaeology. Here, Brill and Wampler outlined how the technique could be used to provenance the lead contents of archaeological objects to lead ore sources around the world, based on the isotopic signature of various leads, which relates them to ‘ores occurring in different geographical areas’ (1967, 63). These different areas have different signatures because they are of varying geological age, something reflected by the individual lead isotopes which form only after the radioactive decay of uranium and thorium (Brill et al. 1965, Brill and Wampler 1967). While the lead isotope ratios used for provenancing are different, they are not unique: areas geologically similar will yield similar lead isotope signatures (Brill 1970). Furthermore, if leads were salvaged and mixed in ancient times, the isotope ratio will be compromised (Brill 1970). Aside from these two limitations, there is little else that could affect the lead isotope reading an object would yield. As such, Brill's method was greeted enthusiastically and he went on to develop the technique, as well as oxygen isotope analysis, in his 1970 publication. Here he demonstrated how the technique could be used both to classify early glasses and to a certain extent characterize the ingredients from which they were made (1970, 143).
In 1965, Brill launched another important innovation in glass analysis, the comparison of interlaboratory experiments in order to verify analytical results (Brill 1965). ‘Originally inspired by a plea from W E S Turner’, according to Freestone, Brill first mooted his idea at the VIIth International Congress on Glass, in Brussels (Brill 1965a, I. Freestone, pers. comm. 2009). It wasn’t until the VIIIth International Congress on Glass in 1968, however, that Brill fully launched his concept of an ‘analytical round robin’, having distributed a number of reference glasses to be tested in different laboratories using a range of current techniques including X-ray fluorescence and neutron activation analysis (1968, 49). When discussing his motive for the experiment, Brill aptly stated: 'The truth is that the chemical analysis of glasses is a difficult undertaking and still remains in some senses an art' (1968, 49). By conducting the round robin experiment, Brill hoped the results gathered from different laboratories would help ‘correlate [...] earlier results’ and ‘calibrate future analyses in reference to one another’, as well as suggest which out of the analytical procedures used was the most accurate and effective (1968, 49). The results of the round robin were presented at the 'IXth International Congress on Glass' in 1971, and showed that, as Brill suspected, there was poor agreement between certain identified elements, and therefore these might be ‘troublesome’ generally across analyses (1971, 97). These included calcium, aluminium, lead and barium, among others (Brill 1971). Aside from their correctional potential, the results, from 45 different laboratories in 15 countries, also provided an enormous data set from which, Brill suggested, the participants could ‘evaluate their own methods and procedures against the findings of other analysts’ (1971, 97). At the time, Brill could hardly have suspected that the data would go on to have such great import, but Croegaard's generation of preferred glass compositions, from statistical analysis of the data, were used successfully by many people until Brill's own reference guide was published in 1999 (I. Freestone, 'pers. comm.', 2009).
Brill made various trips to the Middle East, including accompanying Theodore Wertime's 1968 survey of the ancient technologies of Iran, alongside other great minds such as the noted ceramicist, Frederick Matson (UCL Institute for Archaeo-Metallurgical Studies 2007). In the years 1963-1964, the Corning Museum of Glass and the University of Missouri, following a long history of excavation at the necropolis of Beth She'Arim, conducted an examination of a huge slab of glass, some 2000 years old, that had been languishing in an ancient cistern (Brill and Wosinski 1965). Brill cannot recall who first suggested this slab, measuring 3.4m by 1.94m, could be made of glass, but the only way to test it was to drill a core through its 45 cm thickness and analyse it (Brill 1967, Brill and Wosinski 1965). On analysis of the core, Brill found that the glass was devitrified and stained, and not very homogenous, with a presence of wollastonite crystals throughout (1965, 219.2). Investigation of the manufacture technology required to produce the slab, suggested that in order to produce such a slab of glass, it would have been necessary to heat over eleven tons of batch material, and sustain it at around 1050˚C for between five and ten days (Brill 1967)! His initial interpretation was that the glass must have been heated either from above or from the sides using a kind of tank furnace; a hypothesis that was proven accurate when excavation underneath the slab suggested it had been melted in situ, in a tank whose floor was a bed of limestone blocks with a thin parting layer of clay (Brill and Wosinski 1965, Brill 1967). Brill's interpretation, that the slab and its surroundings suggest ‘some early form of reverberatory furnace’ was the first suggestion of the use of tank furnaces in early glassmaking (1967, 92). The evidence at Beth She’arim encouraged further innovative thought because whilst the slab represented glass production on a grand scale, no associated evidence for glass working was found. Brill had already suspected that historical glassmaking occurred in two phases, the heavy ‘engineering’ stage when the glass is formed from the batch ingredients and the ‘crafting’ stage when the glass is formed into artefacts (Brill, pers. comm., 2009). These stages could occur in combination at one location, or at two differing locales, and the time span of production after the initial glass melt is highly flexible. For Brill, the idea of this ‘dual nature of all glassmaking’ was ‘crystallized’ at Beth She’Arim, where only the raw glass production was represented, and would be reinforced later by the contrasting evidence, where working was favoured over production, found at Jalame, as discussed below (Brill, pers. comm., 2009).
Aside from the aforementioned published results of his analytical round robin and his lead and oxygen isotope studies in the early 1970s, the 1970s saw Brill publish comparatively little, perhaps due to his post as director at The Corning Museum of Glass. Those publications he did pen are largely concerned with the development of lead isotope analysis and are listed in the further reading section. Alas, before Brill could be named Director, however, the museum was to be blighted by an enormous flood, ‘possibly the greatest single catastrophe borne by an American museum’ according to Buechner, Brill's successor in 1976 (1977, 7).
The flood was brought to Corning by Hurricane Agnes, a tropical storm that filled the Chemung River system to bursting until, on the morning of June 23, 1972, the river breached its banks and decimated the town (Martin and Edwards 1977). The Corning Glass Centre was under around twenty feet of water on the lower level's west side, while the museum itself was filled to a water-level of five feet and four inches (Martin and Edwards 1977). 528 of the museum's objects were damaged, the library's rare books were ruined and paper index systems, data and catalogues were all lost (Martin and Edwards 1977). In the wake of this destruction, Brill was named Director, so that his time holding this position, from 1972-1975, would be spent overseeing the complete restoration of the museum. Buechner praises how Brill 'painstakingly' prepared the insurance claim that would support the museum throughout the renovation process and facilitate the replacement of many wonderful objects (1977, 7). Under Brill's auspices, the Corning Museum of Glass was reopened just 39 days after the event, on August 1, but it would be another four years before the collection and library were restored to their former glory (Buechner 1977).
In 1982, Brill joined the International Commission on Glass (Corning Museum of Glass 2009). The International Commission functions through various technical committees, among which Brill saw an opening for TC17, the committee for the Archaeometry of Glass, which he founded shortly after joining. The main purpose of TC17, whose members met for the first time in Beijing in 1984, is ‘to bring together glass scientists, archaeologists and museum curators to present and discuss the results of research on early glass and glassmaking and on the conservation of historical glass objects’, as expressed in their mission statement (Archaeometry of Glass 2005). Brill chaired this committee until 2004 and received the W E S Turner Award from the International Commission of Glass on his departure, in recognition of his contribution as founder (Corning Museum of Glass 2009).
One of the on-running projects of the Corning Museum of Glass published the excavation report from their many field seasons at the ancient glass factory in Jalame, in Late Roman Palestine (Brill 1988, Schreurs and Brill 1984). Brill was called upon to conduct scientific investigations of the huge amount of material generated at the site, in order to exploit the full potential of the artefacts; after all, the site was being excavated specifically because of its role as a glass factory (Brill 1988). Of the vast quantity of glass fragments from Jalame, both vessel sherds and cullet, most were aqua and green and all were soda-lime-silica glasses melted in highly reducing conditions (Schreurs and Brill 1984). Where the melting conditions had been increasingly reducing, a ferri-sulfide chromophore complex was shown to have formed, thus changing the bluey-aqua colour of the glass to an olive, or even an amber shade (Schreurs and Brill 1984). Despite these colour variations, Brill's further chemical analysis showed the vessel glasses to be highly homogeneous in composition, apart from a clear divide where around 40 glasses demonstrated the intentional addition of manganese (Brill 1988). Brill conducted an investigation of the furnace at Jalame, nicknamed the Red Room, in which there was a mysterious absence of glass finds of any kind (Brill 1988). Whilst work at Beth She’Arim had eventually found there to be five firing chambers responsible for heating the one tank, the fragmentary remains at Jalame made it very difficult to interpret the furnace set-up, apart from the fact that they believed there to have been only one firing chamber (Brill 1988).
In the late eighties, Brill contributed to various studies with the Institute of Nautical Archaeology, following the excavation of a number of exciting shipwrecks including the Serçe Liman, and the Ulu Burun (Barnes et al. 1986, Brill 1989). Brill's own technique of lead isotope analysis was to provide a means for provenancing items aboard ship, and thus determine the ship's origin and her ports-of-call. The excavators of the Serçe Liman wanted to know whether she was Byzantine or Islamic, a complicated question for lead isotope analysis as the lead ores of the Eastern Mediterranean share geographical characteristics and therefore overlap (Barnes et al. 1986). Using 900 lead net sinkers divided into six loose groupings, Brill found groups III, V and VI to be Byzantine, that is with ores found in modern-day Turkey (Barnes et al. 1986). Group I, however, was taken to be most indicative of the ship's origin; this group contained net sinkers, but also two ceramic glazes and three glass vessels, all sharing virtually identical lead ores with only one isotopic match, ‘an ore from Anguran, northwest of Tehran’ according to Barnes et al. (1986, 7).
Brill's submissions to the XIVth International Congress on Glass, which took place in New Delhi in 1986, can be seen to represent the origins of his work on the Great Silk Road, the impressive trade route carrying goods from the East through India to Europe. Here, chemical analysis of Early Indian glasses helped Brill determine the ingredients and techniques of production, ‘to make certain broad generalizations as to regions or periods of manufacture’, and therefore to follow an object's movement along the trade route (1987, 1). For the XIVth Congress, Brill conducted atomic absorption spectroscopy (AAS) and optical emission spectroscopy (OES) on samples of 38 glasses from India, and the success of his method was made clear when he was able to separate 21 samples away from those made in the Middle East and Europe (Brill 1987). The glasses were shown to have mixed alkali compositions, a feature that is ‘rare among glasses from more westerly sources’, and therefore Brill concluded that they had definitely been manufactured in India (1987, 4). Brill also collaborated with Mckinnon to conduct chemical analyses of some glass samples from Sumatra, Indonesia, the results of which would be the ‘first data of their kind from this island’ (1987, 1). The results of the study, which also used samples from Java, another important location for the Silk Road, were hoped by McKinnon and Brill to ‘stimulate a greater awareness of glass in the economy [...] of ancient Sumatra and further new lines of research in the archaeology of the region’ (1987, 1).
The beginning of the 1990s saw Brill accorded the Archaeological Institute of America's Pomerance Award for scientific contributions to archaeology; however the decade mostly reflects Brill's continuing dedication to Asian glasses and the study of the Silk Road (Archaeological Institute of America 2009). In Scientific Research in Early Chinese Glass, Brill reflected that in comparison to the knowledge of glassmaking in the West, ‘little is known about Chinese glass and about the role it played in the overall unfolding of glass history on a worldwide basis’ (1991, vii). One reason for this is that glass was never produced in the East in such great quantities as it was in the West but also that archaeological Chinese glasses are often prone to problems (Brill 1991). The difficulties of analysing Chinese glasses were reflected later in the publication where, following the chemical investigation of 71 samples, Brill found that identifying the ‘basic formulation’, or ‘any of the primary batch materials’ of the glasses was still almost impossible (Brill et al. 1991). Brill had greater success in differentiating between Chinese glass samples when using lead isotope analysis, a method that has proven effective in the first instance of identifying Chinese glass as the leads used here are different from those anywhere else in the world (Brill, Barnes et al. 1991). Brill found his Chinese samples to fall into two distinct groups, possessing on one hand the highest, and on the other the lowest, lead isotope ratios he had ever encountered (Brill, Barnes et al. 1991). As such, he was able to show that despite the striking similarity in the glasses’ chemical composition and appearance, the ores from which their leads were sourced must have been from very geologically-different mines (Brill, Barnes et al. 1991).
Brill conducted further investigations of ancient Asian glasses for the Nara Symposium on the Silk Road's maritime route in 1991, ‘to demonstrate [...] that chemical analyses can be useful for learning how glass was traded along the Desert, Steppe, and Maritime Routes of the Silk Road’ (1993a, 71), as well as providing a more technical discussion on glass and glassmaking in China for the Glass Art Society's Toledo Conference in 1993 (Brill 1993b). Further lead isotope analysis, this time on Chinese and central Asian pigments, was conducted with a larger team for the Getty's Conservation of Ancient Sites on the Silk Road, which saw Brill et al. launching studies that held incredible potential for understanding ‘chronological or stylistic differences among Buddhist cave paintings’, or ‘distinguish[ing] between original and repainted parts of individual works’ (1993, 371).
In 1999, Brill published the sum of 39 years worth of results from his chemical investigations at Corning in two volumes of reference material with a third forthcoming (Brill 1999). Brill was reluctant to publish the data without any accompanying interpretation, but he felt that the most important factor was to quickly release the material into a wider sphere, made ‘readily accessible to the scientific community’ (1999, 8). Of Corning's 10,000 research artefacts, the master catalogue contains 6,400 samples, an abbreviated catalogue, or AbbCat, of which is presented in the two volumes (1999, 11). 19 geographical, typological or chronological categories of glass samples are recorded, spanning Brill's various research projects and collaborations, from Egypt to the East (Brill 1999). It also records the results of oxygen isotope analyses, reminding us that Brill was ever one for the integration of different investigative methods.
Since 2000, Dr Brill's interest in Silk Road studies and ancient glass compositions has continued, but his publication rate has slowed somewhat. His years of prolific publication, however, and his willingness to analyse glass from almost every situation have provided the archaeometry of glass with a bounty of reference material, as reflected by the Chemical Analyses of Early Glasses. Despite his official retirement from the Corning Museum of Glass on May 31, 2008, he returned to the laboratory the next day and continues to work, showing no intention of enjoying a retirement proper any time soon (Brill, pers. comm., 2009).
Glass is a non-crystalline solid that is often transparent, brittle and chemically inert. It has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics.
Isotope analysis is the identification of isotopic signature, abundance of certain stable isotopes of chemical elements within organic and inorganic compounds. Isotopic analysis can be used to understand the flow of energy through a food web, to reconstruct past environmental and climatic conditions, to investigate human and animal diets, for food authentification, and a variety of other physical, geological, palaeontological and chemical processes. Stable isotope ratios are measured using mass spectrometry, which separates the different isotopes of an element on the basis of their mass-to-charge ratio.
Tektites are gravel-sized bodies composed of black, green, brown or grey natural glass formed from terrestrial debris ejected during meteorite impacts. The term was coined by Austrian geologist Franz Eduard Suess (1867–1941), son of Eduard Suess. They generally range in size from millimetres to centimetres. Millimetre-scale tektites are known as microtektites.
Lead glass, commonly called crystal, is a variety of glass in which lead replaces the calcium content of a typical potash glass. Lead glass contains typically 18–40% lead(II) oxide (PbO), while modern lead crystal, historically also known as flint glass due to the original silica source, contains a minimum of 24% PbO. Lead glass is often desirable for a variety of uses due to its clarity. In marketing terms it is often called crystal glass.
Jonathan Mark Kenoyer is an American archaeologist and George F. Dales Jr. & Barbara A. Dales Professor of Anthropology at the University of Wisconsin–Madison. He earned his Bachelor of Arts, Master's, and Doctorate degrees at the University of California, Berkeley, finishing in 1983. Kenoyer is president of the Society of Bead Researchers.
Venetian glass is glassware made in Venice, typically on the island of Murano near the city. Traditionally it is made with a soda–lime "metal" and is typically elaborately decorated, with various "hot" glass-forming techniques, as well as gilding, enamel, or engraving. Production has been concentrated on the Venetian island of Murano since the 13th century. Today Murano is known for its art glass, but it has a long history of innovations in glassmaking in addition to its artistic fame—and was Europe's major center for luxury glass from the High Middle Ages to the Italian Renaissance. During the 15th century, Murano glassmakers created cristallo—which was almost transparent and considered the finest glass in the world. Murano glassmakers also developed a white-colored glass that looked like porcelain. They later became Europe's finest makers of mirrors.
Egyptian faience is a sintered-quartz ceramic material from Ancient Egypt. The sintering process "covered [the material] with a true vitreous coating" as the quartz underwent vitrification, creating a bright lustre of various colours "usually in a transparent blue or green isotropic glass". Its name in the Ancient Egyptian language was tjehenet, and modern archeological terms for it include sintered quartz, glazed frit, and glazed composition. Tjehenet is distinct from the crystalline pigment Egyptian blue, for which it has sometimes incorrectly been used as a synonym.
A frit is a ceramic composition that has been fused, quenched, and granulated. Frits form an important part of the batches used in compounding enamels and ceramic glazes; the purpose of this pre-fusion is to render any soluble and/or toxic components insoluble by causing them to combine with silica and other added oxides. However, not all glass that is fused and quenched in water is frit, as this method of cooling down very hot glass is also widely used in glass manufacture.
Roman glass objects have been recovered across the Roman Empire in domestic, industrial and funerary contexts. Glass was used primarily for the production of vessels, although mosaic tiles and window glass were also produced. Roman glass production developed from Hellenistic technical traditions, initially concentrating on the production of intensely coloured cast glass vessels. However, during the 1st century AD the industry underwent rapid technical growth that saw the introduction of glass blowing and the dominance of colourless or 'aqua' glasses. Production of raw glass was undertaken in geographically separate locations to the working of glass into finished vessels, and by the end of the 1st century AD large scale manufacturing resulted in the establishment of glass as a commonly available material in the Roman world, and one which also had technically very difficult specialized types of luxury glass, which must have been very expensive.
Ancient Chinese glass refers to all types of glass manufactured in China prior to the Qing Dynasty (1644–1911). In Chinese history, glass played a peripheral role in arts and crafts, when compared to ceramics and metal work. The limited archaeological distribution and use of glass objects are evidence of the rarity of the material. Literary sources date the first manufacture of glass to the 5th century AD. However, the earliest archaeological evidence for glass manufacture in China comes from the Warring States period.
Forest glass is late medieval glass produced in northwestern and central Europe from approximately 1000–1700 AD using wood ash and sand as the main raw materials and made in factories known as glasshouses in forest areas. It is characterized by a variety of greenish-yellow colors, the earlier products often being of crude design and poor quality, and was used mainly for everyday vessels and increasingly for ecclesiastical stained glass windows. Its composition and manufacture contrast sharply with Roman and pre-Roman glassmaking centered on the Mediterranean and contemporaneous Byzantine and Islamic glass making to the east.
Hellenistic glass was glass produced during the Hellenistic period in the Mediterranean, Europe, western Asia and northern Africa. Glassmaking at this time was based on the technological traditions of the Classical antiquity and the Late Bronze Age, but was marked by transition from limited production of luxury objects made for the social elite to mass production of affordable glass vessels used by the broader public to satisfy everyday needs.
The influence of the Islamic world to the history of glass is reflected by its distribution around the world, from Europe to China, and from Russia to East Africa. Islamic glass developed a unique expression that was characterized by the introduction of new techniques and the reinterpreting of old traditions.
Sasanian Glass is the glassware produced between the 3rd and the 7th centuries AD within the limits of the Sasanian Empire of Persia, namely present-day Northern Iraq, Iran and Central Asia. This is a silica-soda-lime glass production characterized by thick glass-blown vessels relatively sober in decoration, avoiding plain colours in favour of transparency and with vessels worked in one piece without over- elaborate amendments. Thus the decoration usually consists of solid and visual motifs from the mould (reliefs), with ribbed and deeply cut facets, although other techniques like trailing and applied motifs were practised.
The ways in which glass was exchanged throughout ancient times is intimately related to its production and is a stepping stone to learning about the economies and interactions of ancient societies. Because of its nature it can be shaped into a variety of forms and as such is found in different archaeological contexts, such as window panes, jewellery, or tableware. This is important because it can inform on how different industries of sections of societies related to each other – both within a cultural region or with foreign societies.
Sheikh Bureik, locally called Sheikh Abreik or Sheikh Ibreik in recent times, was a Palestinian Arab village located 10 miles (16 km) southeast of Haifa. Situated at an ancient site that shows evidence of habitation as early as the Iron Age, it was known as Beit She'arayim in the Roman and Byzantine periods and became an important center of Jewish learning in the 2nd century, with habitation continuing during the Early Islamic period and limited signs of activity from the Crusader period.
Archaeometallurgical slag is slag discovered and studied in the context of archaeology. Slag, the byproduct of iron-working processes such as smelting or smithing, is left at the iron-working site rather than being moved away with the product. As it weathers well, it is readily available for study. The size, shape, chemical composition and microstructure of slag are determined by features of the iron-working processes used at the time of its formation.
The history of glass-making dates back to at least 3,600 years ago in Mesopotamia. However, some writers claim that they may have been producing copies of glass objects from Egypt. Other archaeological evidence suggests that the first true glass was made in coastal north Syria, Mesopotamia or Egypt. The earliest known glass objects, of the mid 2,000 BCE, were beads, perhaps initially created as the 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. Glass products remained a luxury until the disasters that overtook the late Bronze Age civilizations seemingly brought glass-making to a halt.
J. H. Hobbs, Brockunier and Company was one of the largest and best known manufacturers of glass in the United States during the 19th century. Its products were distributed world–wide. The company is responsible for one of the greatest innovations in American glassmaking—an improved formula for lime glass that enabled American glass makers to produce high-quality glass at a lower cost. The firm also developed talented glassmakers that started glass factories in Ohio and Indiana.
The Xichengyi culture (Ch:西城驿文化) was an ancient culture in the central Heihe River region of the Hexi corridor, from 2,000 to 1,600 BCE. It is contemporary with the Qijia culture to its southeast. It succeeded the Majiayao culture in the area, and preceded the Siba culture.