Roman Glass Research Articles

Preliminary non-invasive study of Roman glasses from Jesolo (Venice), Italy

Archaeological excavations at ‘Le Mure’ site (Jesolo, VE, Italy) have followed each other since the sixties, when the first evidence of an Early Medieval church (6th–7th century AD) was found under the ruins of a Medieval Cathedral (11th–12th AD). The last few years of investigations by Ca’Foscari University have led to the collection of large amounts of glass fragments, including many tesserae, dating between the 4th and the 12th centuries AD. A selection of glass fragments and mosaic tesserae taken from the excavations performed in 2013–14 at this site were studied by means of reflectance spectroscopy in order to identify their chromophore ions, in particular Cu0, Cu2+, Co2+, Fe2+ and Fe3+, which were detected in both transparent and opaque samples. In addition, the use of high resolution close-up images allowed for the attribution of surface characteristics to specific manufacturing techniques, while glass chemistry was studied in order to group them into known compositional classes. This study, carried out by non-invasive analytical techniques that allowed for the acquisition of preliminary data, will prove useful in driving further methodologies involving other non-invasive and micro-invasive analysis in order to obtain archaeometric information that can be related to concurrent archaeological results.

Drachma

Laura Kasischke | 13 I’m not interested in a single thing in this museum case. Not that coin, filthy, ancient. Not that little marble phallus. Not this tiny Isis, or this Byzantine slave bracelet, or that blue-­ green shard of Roman glass. What I want is that lost shoebox full of faded snapshots back. But I moved too many times when I was young. Couldn’t settle. Didn’t care. A friend’s garage. My ex’s basement. A rented storage shed. And now my grandfather is still there, waiting in a worn-­ out chair, half-­ awake, a book closed in his lap. He poetry Drachma Laura Kasischke 14 | Laura Kasischke held strange beliefs and drank too much. Collected things. He made a lot of noise the day he died. I was a child, not in the room itself, but also not outside. Years later my mother would admit it might have been wrong to leave a kid in front of a television set for seven hours, listening to that. But I was sloppy drunk when she said this, and she was dying, too, by then, and if I hadn’t been so careless for so long with my possessions, I could show you now a photo of his face. Instead, it’s in some box I left someplace. Some Greek soldier’s drachma, wasted. Some Roman housewife’s broken vase. ...

Weathering and deterioration of archeological glasses from late Roman Sicily

AbstractGlass is found at archeological excavations in a variety of conditions ranging from pristine—where no deterioration is visible—to very heavily degraded. Although the chemical processes of glass deterioration have been extensively studied, they are not yet entirely understood, due in part to the numerous factors that must be considered, from the composition of the glass paste and its manufacture to the type of soil in which the glass is buried. In this study, we analyze an assemblage of Late Roman glass from the catacombs of Saint Lucy in eastern Sicily, in order to study the effects of this particular hypogeal environment on glass. The study regards the correlation between the weathered glass surfaces and the compositional changes occurred in the samples. Close attention is paid to optical observations of the outer layers of the glasses as manifestations of chemical deterioration of the bulk. The chemical analysis of the fragments of glass was carried out nondestructively using PIXE‐PIGE analyses without any sample preparation. Weathering was observed with an optical microscope.

The role of IRT in the archaeometric study of ancient glass through XRF and FORS

The process of degradation of archaeological glass subjected to centuries of burial can be of great relevance: typical consequence of degradation in the original vitreous material is rainbow-like iridescence due to chemical alteration of surface layers, salts formation and ion migration. The research presented in this paper is focused on the study of a collection of Roman glass (I - II century A.D.) held by the Museo Civico Etnografico Archeologico Fanchini of Oleggio, Italy. Chemical characterization (namely flux, chromophores and opacifiers determination) has been performed by a combination of X-Ray Fluorescence (XRF) and Fibre Optics Reflectance Spectroscopy (FORS) in the UV–Vis-NIR region. Conservation conditions have been studied and degraded areas have been mapped through Infrared thermography (IRT). IRT is a non-invasive method typically used to measure the apparent temperature of objects and represent it as pseudo-colour images. In the present work, we demonstrate the feasibility of IRT for identifying and mapping glass substrate defects due to ageing of glass, assuming that they may be considered as thermal anomalies. Thermogram sequences have been processed by high order statistical analysis, which is particularly suitable since it is based on automated processes where the output is a single representative image. The use of a thermal camera allows furthermore to perform remote analysis in areas hardly reachable in a fast and effective way.

To be purple or not to be purple? How different production parameters influence colour and redox in manganese containing glass

The purpose of this paper is to understand why manganese containing Roman glass could be purple or colourless in spite of having very similar chemical compositions. The strategy followed to tackle this question consists in the production of glass with the same chemical composition as Roman glass whereby various production parameters were controlled and systematically analysed. It is shown that redox and colour of glass is more likely to have been managed through internal control through the choice of raw materials and the addition of organic matter. The main difference between ancient and modern glass production relies on the lower melting temperature of Roman furnaces, so that sulphate would have played a less important role in the redox determination.

Analysis of Roman and other archaeological glasses by 12 MeV proton activation analysis

14 elements were determined, at trace level, in Roman and other archaeological glasses by 12 MeV proton activation analysis. The results show that the natural glass from Mongolia and Brazilian quartz are the purest of all the samples analysed with detection limits at 1 ppm level for Ti, V, Cr, As, Sr, Y and Zr. In several cut pieces of one variety of Roman glass, using the concentration of Ca, Ti, Fe, Sr and Sb as markers, the homogeneity of glass production and their potential use in provenance studies were discussed.

The study of the historical development of glass in ancient times

Abstract: This paper discusses historical development of glass in ancient times, identify the most important characteristics of glass in every era of time, through the study of their properties, chemical composition of the types of glass and production methods, through the study of some archaeological models of global museums to reach the most distinctive characteristics of each era ,The aim of this paper is to explore these aspects by using a combination of focused studies and case studies in various ancient and historical periods. Each case study in ancient Egyptian period, Roman Middle East, and the Islamic world.keywords: historical development of glass, Ancient Egyptian, Roman glass, Islamic glass, chemical composition, glass techniques.I. INTRODUCTION Ancient Egyptian GlassAs early as the third millennium B.C., craftsmen in Mesopotamia discovered how to glaze jewelry and small objects with colored glass. The new material joined other vitreous glazes, like faience, as a less expensive substitute for rare and precious stones, such as lapis lazuli. Subsequent developments, especially the use of simple molds, enabled craftsmen to form objects entirely from glass.In all likelihood, the Egyptians learned glassmaking from their Asiatic neighbors, possibly from captives taken during Egyptian military campaigns in the East under the eighteenth-dynasty pharaoh Thutmosis III (1490–1436 B.C.). The glass industry, once transplanted to Egypt, grew vigorously, fueled in part by the abundance of the raw materials required to manufacture glass. Egyptian workshops not only produced a variety of wares for consumption by the royal court and aristocrats, who could afford such luxuries, but also exported large quantities of raw glass.

Glass in imitation of exotic marbles: An analytical investigation of 2nd century AD Roman sectilia from the Gorga collection

Abstract The materials uncovered in excavations in several provinces of the Roman empire provide important evidence to the frequent use of glass in most precious opera sectilia. Glass pieces imitating a dozen of ancient marbles and exotic stones have been identified in the collection belonged to Evangelista Gorga, samples of which were selected for analysis in order to obtain valuable information on the Roman glassmaking technology of the 2nd century AD, especially on coloration techniques. The monochrome and polychrome glass tesserae replicating precious marbles and rare stones were: porfido verde antico, litomarga verde, turquoise, pavonazzetto, gabbro eufotide, diaspro nero e giallo, semesanto, alabastro tartarugato, rosso antico, cipollino rosso, giallo antico, and onyx. XRF quantitative chemical composition was determined allowing the types of glass used and the colouring techniques to be identified. Results have been compared with similar data obtained by studies on coloured Roman glass and mosaic tesserae. Similarities and discrepancies are discussed and hypotheses are suggested on the technology of this extraordinary Roman production.

Evoking History: The Belt & Road Initiative and Regional Connectivity

As the historical symbol behind China’s 21st century development strategy of the Belt & Road Initiative (BRI), the notion of the Silk Road(s) was never that of one singular passageway, but a network of contacts across the Eurasian continent, over both land and water. For more than two millennia, commerce, conquests, and diplomatic activities took place across this trans-continental network, bringing with them people, commodity, and ideas. In this paper, I will discuss how historical cultural spheres crossed over where the Silk Road(s) linked one group of people to another, promoting regional connectivity and co-prosperity. Using specific objects as case study, the Hoxne pepper pot and Roman glass bowls demonstrate how, as early as the Roman period, the Chinese central kingdom was already in contact with the Roman empire. Material cultural contact and adaptation was never a one-way trend, but always with ramifications to be experienced in the everyday life of all the peoples involved. Since its inception, the Silk Road(s) existed for, and in turn, benefited from, speed and efficacy in the transportation of people and goods. As the era of camels, horses, and sailing ships fades into history, China’s push for the development of high-speed rail emerges to be the most efficient and favored mode of transportation to realize true regional connectivity for BRI to kick into action.

Novel TEM Microscopy and Electron Diffraction Techniques to Characterize Cultural Heritage Materials: From Ancient Greek Artefacts to Maya Mural Paintings.

To understand in-depth material properties, manufacturing, and conservation in cultural heritage artefacts, there is a strong need for advanced characterization tools that enable analysis down to the nanometric scale. Transmission electron microscopy (TEM) and electron diffraction (ED) techniques, like 3D precession electron diffraction tomography and ASTAR phase/orientation mapping, are proposed to study cultural heritage materials at nanoscale. In this work, we show how electron crystallography in TEM helps to determine precise structural information and phase/orientation distribution of various pigments in cultural heritage materials from various historical periods like Greek amphorisks, Roman glass tesserae, and pre-Hispanic Maya mural paintings. Such TEM-based methods can be an alternative to synchrotron techniques and can allow distinguishing accurately different crystalline phases even in cases of identical or very close chemical compositions at the nanometric scale.

РИМСКИЕ СТЕКЛЯННЫЕ СОСУДЫ СЕРЕДИНЫ I – СЕРЕДИНЫ III ВВ. Н.Э. ИЗ САРМАТСКИХ ПОГРЕБЕНИЙ ВОЛГО-ДОНСКОГО МЕЖДУРЕЧЬЯ, НИЖНЕГО ПОВОЛЖЬЯ И ЮЖНОГО УРАЛА

РИМСКИЕ СТЕКЛЯННЫЕ СОСУДЫ СЕРЕДИНЫ I – СЕРЕДИНЫ III ВВ. Н.Э. ИЗ САРМАТСКИХ ПОГРЕБЕНИЙ ВОЛГО-ДОНСКОГО МЕЖДУРЕЧЬЯ, НИЖНЕГО ПОВОЛЖЬЯ И ЮЖНОГО УРАЛА

Roman window glass in Hispania Baetica: Glass origin and manufacture study through electron microprobe analysis

Twenty five samples of Roman window glass of some archaeological sites situated in the Roman province Baetica: Acinipo (Ronda, Málaga), Carmo (Carmona, Seville), Herrera (Seville), Astigi (Écija, Seville), Cortalago (Minas de Riotinto, Huelva) and Torreparedones (Baena, Córdoba), were selected for Microprobe Analysis (EPMA). All of them are window glasses glossy/matte, manufactured by cooled and stretch processes. The aim of this study is to know aspects related to chemical composition of the glasses, the glass origin used in their production and manufacture processes of a typology of glass that is virtually unknown in the South of Hispania. The results reflect that all of them are silica-soda-lime glasses with compositions near to blue-green glasses typical of Roman times. However, except two samples, the group shows a feature unusual in other Roman glasses analysed: high manganese and low iron levels. The comparison with other similar samples of the same period, allows to hypothesize that an origin in the Levantine coast would be possible for the glasses used in the window panes studied. Related to the manufacture processes of these panes, chemical analysis in different areas of the same fragment reveal that panes are not homogeneous. Potassium small changes near to the matt surface of the panes could be associated with their manufacture.

Emeritus Professor Jennifer Price (1940–2019)

Jenny was born in Stourbridge, Worcestershire to a family of glassmakers, a fact that was presumably influential in eventually framing her research interest in Roman glass. That said she joined an ...

LA-ICP-MS labels early medieval Tuscan finds from Siena and Donoratico as late natron glass

The late antique/early medieval age in Central Italy is a well-suited context to verify the implications of the end of the natron glass supplies, and to explore the beginnings of the new plant-ash glass technology. We present the results of a LA-ICP-MS analysis campaign conducted on archaeological glass finds excavated at the Santa Maria della Scala hospital site in Siena and in Donoratico. This provided us with major, minor and trace element quantitative data for 49 glass samples belonging to drinking vessels and lamps, dated mainly between the 5th and the 8th century. On the basis of these data, we have sought to identify the working processes and possible glassware trade that are reflected in the glass composition. Major and minor element contents revealed that most samples, also at the later boundary of the explored timeframe, fit well within known late Roman glass classifications (e.g. HIMT, Levantine). Trace element analysis provided further information on the raw materials that were used in the glassmaking process, indicating the use of coastal sands as a silica source and allowing us to formulate different hypotheses on the materials used for the colouring process.

Novel characterization techniques for cultural heritage using a TEM orientation imaging in combination with 3D precession diffraction tomography: a case study of green and white ancient Roman glass tesserae

We present new transmission electron microscopy (TEM) based electron diffraction characterization techniques (orientation imaging combined with 3D precession electron diffraction tomography-ADT) applied on cultural heritage materials. We have determined precisely unit cell parameters, crystal symmetry, atomic structure, and orientation/phase mapping of various pigment/opacifier crystallites at nm scale which are present in green and white Roman glass tesserae. Such TEM techniques can be an alternative to Synchrotron based techniques, and allow to distinguish accurately at nm scale between different crystal structures even in cases of same/very close chemical composition, where is also possible to visualize between different crystal orientations and amorphous/crystalline phases. This study additionally demonstrates that although opacifiers in green and white tesserae are found to have average Pb2Sb2O7 cubic and CaSb2O6 trigonal structures, their pyrochlore related framework can host many other elements like Cu, Ca, Fe through ionic exchanges at high firing temperatures which in turn may also contribute to the tesserae colour appearance.

Late Hellenistic and early Roman slumped and cast glass vessels from the House of Orpheus at Paphos, Cyprus. An interim report

This paper provides the preliminary results from an integrated study of the Hellenistic and early Roman glass vessel assemblage from the large domestic context at Paphos named the House of Orpheus. The homogeneous appearance of the omnipresent slumped and cast vessels in late Hellenistic and early Roman contexts within the entire Mediterranean makes it fairly complex to define the origin of specific assemblages when only studying the external features.We present here the results of a combined study of in-situ optical analysis by means of absorption spectroscopy and chemical analyses with SEM-EDS and LA-ICP-MS. In a first step 107 fragments were optically analysed to categorize possible glass groups and 54 selected pieces were sampled to characterize their chemical composition. Four optically defined glass types can be distinguished with respect to the use of a decolouring or colouring agent and the impact of the furnace condition. The chemical analysis techniques define four distinct subgroups within the homogeneous cluster of Levantine glass.

A Mosaic of Colors: Investigating Production Technologies of Roman Glass Tesserae from Northeastern Italy

In the current study, a set of 60 glass tesserae from two disrupted Roman mosaics located in Pordenone and Trento (northeastern Italy) are analyzed, with the aim of investigating the coloring and opacification techniques, with a focus on the causes of specific textural features. All the available colors and textures were selected for archaeometric analyses, in order to guarantee the full characterization of both assemblages and comparisons between the two sites. The applied analytical protocol comprises micro-textural and preliminary chemical characterizations of the tesserae by means of OM and SEM-EDS, mineralogical analysis of the opacifiers by XRD and chemical analysis of the glassy matrices by EPMA; in addition, on specific tesserae, micro-Raman spectroscopy, FORS, and EPR were also performed to clarify the type of opacifer, coloring ion and oxidation state, respectively. Results show that both the base-glass and the coloring/opacification techniques identified are consistent with the presumed Roman dating of the mosaics. All the tesserae are natron-based and chemically comparable with major Roman compositional groups, except for red samples. Antimony-based opacifiers are identified in most of the blue, turquoise, white, yellow and green tesserae, and copper-based opacifiers in the red ones; cobalt and copper are the most frequent ionic colorants used to obtain various shades of blue, turquoise and green colors. Despite the general comparability of both assemblages with the published data on glass tesserae coeval in age, the present study shows differences in the technological solutions used for obtaining the same color, and less common coloring and opacification techniques in three samples from Pordenone. The banded textures of some tesserae were also carefully investigated, and multiple factors influencing the changes in color (different distribution or relative abundance of opacifiers, crystal size, micro-texture, chemical composition of glassy matrix) are identified.

Something old, something new: the late antique mosaics from the catacomb of San Gennaro (Naples)

Naples assumed an important political and economic role within the region of Campania during the late antique period. LA-ICP-MS data of 285 glass tesserae from the catacomb of San Gennaro in Naples confirm that the surge in building activities in the late fourth and early fifth century CE was accompanied by imports of new materials for the production of mosaic tesserae. Our results from Naples identify a substantial number of Jalame-like Levantine glasses for which there is no parallel within the Italian Peninsula. Only few scattered examples of this type of base glass are found among the published data from Aquileia, Ravenna and the Villa of Faragola, pointing to a link between the supply of glass and the sites' connectivity and economic strength. This seems to have changed after the fifth century. Elemental analyses, combined with SEM-EDS and micro-Raman indicate that the mosaics dating from the fourth to the eighth/ninth century CE in the catacombs of San Gennaro were overwhelmingly made from reused first- to fourth-century Roman base glasses opacified with calcium antimonate. The reuse and recycling of Roman glass and Roman tesserae is a common feature of mosaic assemblages in Italy more generally. The definition of a Roman spectrum tesserae reference group revealed this dependence on old Roman material throughout the first millennium CE.

Amorphous glass fragments from archaeological surface surveys: Potential chronological use of ion beam and isotopic analytical characterization

Analytical techniques have been used to implement the archaeological information from surface surveys. We have shown that the compositional comparison of amorphous samples, e.g. glass, can provide important chronological information when compared with findings from other sites. A group of 61 glass fragments, recovered from an archaeological surface survey at the site of the Roman city of Duratón (1st to 3rd century AD), near Segovia, Spain, have been analysed by combined Particle Induced X-ray/Gamma-ray Emission (PIXE-PIGE) techniques and by isotope dilution mass spectrometry. Four groups of objects were identified. The largest group by far, corresponds to the typical sodium-rich natron-made Roman glass. Compared with data reported in previous studies, including a few on the Iberian Peninsula, the composition of Duratón natron glass is similar to that of the widespread Roman 1st–3rd century AD glasses. The glasses of the nearby Patones, six of which have been analysed in this study, belong, on the contrary, to the so-called HIMT glass. This is compatible with the soda-lime-silica glass pattern observed in the Western Mediterranean. HIMT glass is dominant in this area from the 4th century onward. HIMT glass products are much easier to make and less expensive. Strontium and neodimium isotope analysis confirms the compositional proximity of the Duratón glasses to three groups of 1st–3rd century samples from Barcino, Lyon and the Iulia Felix wreck and point to a production of the glass in the Eastern Mediterranean. Pliny the Elder in his Naturalis Historia had specifically mentioned the glass production of Hispania and Gallia, which should hopefully be confirmed by the findings in the corresponding regional sites. This is the case for Gallia but not yet for the Iberian Peninsula, where few Roman glass analyses have been completed.

Clarity and brilliance: antimony in colourless natron glass explored using Roman glass found in Britain

This paper discusses the development of Roman antimony decolourised natron glass, its dominance, and subsequent decline, using new trace element data for colourless glass found in Britain. Experimental glasses are used to investigate the influence of different proportions of raw materials (particularly the ratio of natron to calcium carbonate) on the resulting transparency or opacity of glass when antimony is added. Focusing on the 1st to 3rd centuries AD, the study has found that (1) There are chronological differences in antimony colourless glass compositions including (a) some early vessels have abnormally low calcium, aluminium and barium levels; (b) 1st/mid-2nd-century AD vessels in Britain may also contain up to 0.6 wt% lead oxide whereas mid-2nd/3rd-century AD vessels contain less than 300 ppm, and (c) the antimony content tends to decline over time. (2) These developments can be linked to production and recycling practices; but trace elements suggest that all of these antimony colourless glasses share an origin, probably Egypt. (3) Crucially, production of experimental glasses illustrates the inherent suitability of a sodium-rich, calcium-poor base glass composition for making antimony colourless glass, as it readily dissolves added antimony; conversely lower-sodium, higher-calcium glasses start to form opacifying calcium-antimonate crystals with the same quantities of antimony. Thus, the sodium-rich, calcium-poor glass composition from Egypt was ideally suited for decolourising with antimony and formed a water-clear glass. The calcium-rich Syro-Palestine glasses were more easily opacified with antimony to make opaque glass, but were decolourised with manganese, not antimony.