The Belgammel Ram,a Hellenistic‐Roman Bronze Proembolion Found off the Coast of Libya: test analysis of function,date and metallurgy,with a digital reference archive

The Belgammel Ram was found off the coast of Libya in 1964, and examined during 2008–9. The following techniques were used: surface non‐contact digitizing using a laser scanner, reflectance transformation imaging using polynomial texture mapping and hemi‐spherical harmonics, digital photogrammetry with dense surface modelling, structured light optical scanning, and X‐ray fluorescence analysis. For internal structure the ram was examined by X‐radiography and 3‐D X‐ray tomography. Metallurgical composition was studied by micro‐drilling and subjecting the samples to scanning electron microscope X‐ray micro‐analysis, micro X‐ray fluorescence and X‐ray backscatter. The lead isotope composition was analysed. The alloy has average percentage composition Cu = 86.9, Sn = 6.3, Pb = 6.6, and Zn = < 0.10. The Belgammel Ram is probably a Hellenistic‐Roman proembolion from a small military vessel or tesseraria. The archived data are at the Faculty of Engineering and Environment, Engineering Sciences, Material Data Centre, University of Southampton ( muvis@soton.ac.uk ).     

A Multidisciplinary Approach to the Study of Archaeological Mortars from the Town of Ammaia in the Roman Province of Lusitania (Portugal)

The Roman town of Ammaia (in Marvão Region) is considered one of the most important recent findings of the Roman presence in Portuguese territory. It was settled in Republican times and abandoned in the seventh century. In this research, 17 masonry mortars and renders from the West Tower (South Gate), the residential area near the West Tower, the macellum, the peristylium, the public bath building, the podium of the temple and the portico of the forum were analysed. The methodology of chemical, mineralogical and microstructural characterization has involved several complementary techniques, including stereomicroscopy, X‐ray diffraction, thermal analysis and scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy. The results indicate that the mortars from the beginning of the town's edification were mainly composed of soil (clays). Later, during the main Roman building period, mortars were composed using a calcitic binder and the mortar composition varied according to their use and function. The samples from a period subsequent to the Roman occupation are based on a dolomitic binder. From the present study, relevant information has been acquired about the technological evolution of Roman construction in Ammaia, the historical context of the archaeological structures and guidelines for the conservation and restoration of mortars.     

ANALYSING ARCHAEOLOGICAL BASALT USING NON‐DESTRUCTIVE ENERGY‐DISPERSIVE X‐RAY FLUORESCENCE (EDXRF): EFFECTS OF POST‐DEPOSITIONAL CHEMICAL WEATHERING AND SAMPLE SIZE ON ANALYTICAL PRECISION*

Energy‐dispersive X‐ray fluorescence (EDXRF) has been commonly used to determine geological sources of volcanic glass artefacts, but its ability to discriminate between basaltic sources is less developed. We examine the precision and accuracy of non‐destructive EDXRF for basalt artefacts by analysing varying size and weathering characteristics. The experiments identified no appreciable effect in reproducibility or measured composition due to thickness (down to 1 mm) or natural weathering of pre‐contact flake scars for the 17 elements measured in this study. Samples with surface area less than 100 mm², however, show significant variability in measured composition and reproducibility.     

FIELD AND LABORATORY MULTI‐TECHNIQUE ANALYSIS OF PIGMENTS AND ORGANIC PAINTING MEDIA FROM AN EGYPTIAN COFFIN (26TH DYNASTY)

This paper describes the physico‐chemical analyses performed on an Egyptian wood coffin on the occasion of its restoration in the hall of the National Archaeological Museum of Parma (Italy), with the aim of investigating the pigments and organic materials originally used. Pigment determination was performed both in situ by a portable energy‐dispersive X‐ray fluorescence (EDXRF) spectrometer and in the laboratory using a micro‐Fourier‐transform‐infrared (micro‐FTIR) and a Fourier‐transform (FT) Raman spectrometer. The identification of organic materials was performed through gas chromatography – mass spectrometry (GC–MS) and micro‐FTIR analysis. Amongst the pigments, special attention was paid to the green, which appeared to be severely degraded and was examined using powder X‐ray diffraction (XRD) and scanning electron microscopy – energy‐dispersive X‐ray (SEM–EDX) in addition to the above‐cited techniques. Other materials used in the polychromatic decorations are Egyptian blue, cinnabar and possibly orpiment, while calcium carbonate was used for the ground layer. The organic materials were identified as beeswax, mastic and gum arabic, sometimes as mixtures.     

Studying the process of enamel powder preparation for émail champlevé by colour measurements and μ‐X‐ray mappings

Colour measurements and non‐destructive μ‐X‐ray mappings have been used for the first time in a comprehensive study of medieval émail champlevé works from different production areas in France and Germany. This approach has given a new insight into the enamel powder preparation process of the glass material used for enamelling. Colour measurements demonstrated that all production centres used glass of very similar hues, but with large differences in colour saturation. The μ‐X‐ray mapping results of blue enamels are described by a semi‐qualitative approach. Significant variations in oxide contents of lead, cobalt, manganese and antimony oxides were found. The variations suggest that more than one glass material was used to prepare the powder for enamelling. The variations in antimony and cobalt show that glass had different degrees of opacity and colour depth. The manganese and lead contents, which do not correlate with the cobalt or antimony contents, indicate that probably glass of different base compositions was used to prepare the enamel powder for one champlevé field.     

ANALYTICAL CHARACTERIZATION OF ROMAN PLASTERS OF THE ‘DOMUS FARINI’ IN MODENA*

The paper refers to the analytical characterization of Roman painted plasters dating back to the second century ad . The following techniques were used: optical microscopy (OM), scanning electron microscopy (SEM–EDS), micro‐Raman and Fourier transform infrared spectroscopies (µ‐Raman and FT–IR), X‐ray diffraction (XRPD), colorimetry and thermal analyses (TG/DTA). The investigation analysed the chemical composition and structure of the plasters, the chemical composition of the pigment layers, the use of binders and any chemical alteration of pigments as well as deterioration of the samples. Stratigraphic analysis of plasters allowed identification of their individual components, which proved helpful in finding out more about the mural painting technique employed.     

Black Gloss Pottery: Production Sites and Technology in Northern Etruria,Part II: Gloss Technology

The present study aims to understand the reasons for the visual differences of black gloss pottery found in northern Etruria. The results obtained by conventional (scanning electron microscope, electron microprobe) and synchrotron (X‐ray diffraction, X‐ray absorption spectroscopy) techniques indicate that the thickness, porosity or chemical composition of the different types of gloss cannot be used as the principal distinguishing factor. The size of quartz or feldspar crystals may well be a critical factor responsible for the matt effect in some samples, while the range of mixtures of iron compounds indicated by XRD and XAS could be the reason for differences in colour and reflectivity. The Fe L‐edge XAS results in particular show that a correlation does exist between the oxidation state characteristics and the visual appearance. The Si, Fe and Al contents seem to further discriminate the different types of gloss that have differing visual appearances.     

BYZANTINE CERAMIC PRODUCTION FROM CUMA (CAMPI FLEGREI,NAPOLI)*

Samples of table and cooking ware, dating back to the Byzantine period of the ancient Greek colony of Cuma, were analysed by optical microscopy, X‐ray diffraction, X‐ray fluorescence and scanning electron microscopy, in order to reconstruct the main technological properties of these manufactures. The comparison of minero‐petrographical data from these samples with those of some kiln wastes allowed us to hypothesize a local manufacture for most of the investigated specimens and to confirm the relative reference groups. A restricted number of samples did not link with the main groups, indicating a regional (or maybe extra‐regional) production, in agreement with the widespread circulation of this high‐medieval ceramic production in southern Italy.     

The production and technology of glazed ceramics from the middle ages,found in the saepinum territory (Italy): a multimethodic approach*

A collection of ceramics from the Middle Ages found in Altilia and Terravecchia (the Saepinum area, Campobasso, Italy) were characterized by using different mineralogical analyses to investigate their provenance and production techniques. The body ceramic was investigated using Rietveld phase analysis of X‐ray powder diffraction patterns, X‐ray fluorescence spectrometry and scanning electron microscopy. The chemical compositions of the coatings were measured by scanning electron microscopy and their mineralogical compositions were determined using a particular technique of X‐ray small‐angle scattering (SAS) optimized for studies of thin films. Moreover, the material used for decoration was studied using micro‐Raman spectroscopy. The archaeometric results confirmed the distinction into two different ceramic classes, already individuated from archaeological analysis: the Altilia objects belong to the protomajolica class, whereas the objects from Terravecchia are RMR (ramina‐manganese‐red) ceramics. A comparison between the chemical and mineralogical compositions of good‐quality ceramic objects and those of waste products indicated local production of the ceramics. A sharp distinction was found in the chemical composition of the coatings: the Altilia products have tin‐opacified lead glazes, while the Terravecchia ones have transparent high‐lead glazes. Among the Altilia products, the unsuccessful process that produced a large quantity of discarded materials was attributed to the high lead content of the glazes. In fact, the principal advantage of the high lead content was to make the preparation and application of the glaze suspension easier, but the risk of reduction of lead oxide to metallic lead was greatly increased. Using micro‐Raman spectroscopy, the following minerals were identified as pigments: pyrolusite for the dark colour, malachite for green, lepidocrocite for yellow and hematite for red.     

COLOURED OPAQUE GLASS BEADS OF THE MEROVINGIANS*

Monochrome coloured opaque glass beads of the Merovingians have been examined by different analytical methods. A large number of mostly unprepared beads have been measured by X‐ray fluorescence analysis. X‐ray diffraction was used for the identification of the crystalline colouring and opacifying pigments, and electron probe micro‐analysis as well as scanning electron microscopy were applied to study the composition and the microstructure of a white, brown, green, orange and yellow glass bead. After subtracting the content of colouring oxides of the glass beads and normalizing the residual values to 100% an identical soda‐lime‐glass matrix was obtained. The origin of the colouring metal oxides is discussed.     

DISCOVERY AND CHARACTERIZATION OF AN UNKNOWN BLUE‐GREEN MAYA PIGMENT: VESZELYITE*

Blue‐green mosaic and polychrome masks and funerary offerings from the royal tombs of Calakmul, Mexico, were analysed by scanning electron microscope equipped with energy dispersive X‐ray spectroscopy (SEM‐EDS), X‐ray diffraction (XRD), and particle induced X‐ray emission (PIXE). This led to the first identification of the use of veszelyite, a rare hydrated copper‐zinc phosphate, as green pigment. Analyses of a geological sample of this mineral have been done to confirm the characterization of this Mayan pigment, which might help determine pre‐Columbian trade routes of precious and luxury objects in the ancient Maya Classic period (ad 250–800).     

MICROSTRUCTURAL CHARACTERIZATION OF EARLY WESTERN GREEK INCUSE COINS*

In this research, we studied the compositional, crystallographic and microstructural properties of a series of incuse silver didrachmae stemming from the Achaean colonies of Metapontum and Caulonia. In this paper, we address the following points: (i) the metal sources, (ii) the fabrication process and (iii) degradation phenomena, such as incrustation and embrittlement. In this investigation, we employed energy‐dispersive X‐ray fluorescence spectroscopy, X‐ray diffractometry, and scanning electron and optical microscopies. The patina is mainly composed of chlorargirite. The coins consist of a silver‐rich alloy containing ～ 1% of Au and Cu. Metallographic and local compositional analyses revealed a complex scenario of inclusions. In one instance, unalloyed copper grains, two‐phase copper/bismuth globuli and high‐bismuth filaments were observed. In other cases, globular Cu ₂ S (chalcocite) inclusions were noticed. The presence of SiO ₂ and iron oxide inclusions is ubiquitous in these samples. Distorted twin lines and strain lines can be detected, denoting work‐hardening of recrystallized flans. Grain polygonalization can occasionally be noticed, hinting at secondary recrystallization processes. The irregularly shaped iron oxide particles often act as crack initiation sites. Fracture facets are generally intergranular. On some areas, intergranular decohesion is also observed. Open cracks sometimes contain AgCl. The strain lines that can be noticed on the fracture surfaces indicate work‐hardening and residual microstructural deformation. Information regarding inclusions and the presence of significant amounts of gold can be tentatively used to address provenancing and fabrication issues.     

A MULTI‐ANALYTICAL APPROACH FOR THE CHARACTERIZATION OF COMMODITIES IN A CERAMIC JAR FROM ANTINOE (EGYPT)*

This paper describes a multi‐analytical chemical study performed on the original, almost totally conserved, content of a small ceramic jar from the Antinoe archaeological site (fifth to seventh centuries ad, Roman Egypt) and now belonging to the archaeological collection of the Istituto Papirologico ‘Girolamo Vitelli’ (Florence, Italy). Scanning electron microscopy with an energy‐dispersive X‐ray spectrometer (SEM–EDX), Fourier transformed infrared spectroscopy (FTIR) and X‐ray diffraction (XRD) were all used to characterize the inorganic components of the archaeological material. The organic substances were analysed using FTIR, direct exposure mass spectrometry (DE–MS) and gas chromatography – mass spectrometry (GC–MS). The inorganic component essentially consisted of halite (NaCl). Among the NaCl crystals, lamellar elements were identified. They were chemically characterized by carbonato‐apatite and showed a concentric morphology typical of the scales of small fish. The most prevalent organic constituents of the sample were monocarboxylic acids, α,ω‐dicarboxylic acids, and cholesterol and its oxidation products. The organic material composition was consistent with the occurrence of lipids of animal origin. In addition, diterpenes related to pine pitch were also identified. The overall results suggest that the material recovered in the small ceramic jar found in Antinoe is a residue of fish‐based pickles such as garum, muria, allex and liquamen, which were commonly used in Roman times.     

Beyond the Visible: Combined Neutron and X‐ray Imaging of an Altar Stone from the Former Augustinian Church in Fribourg,Switzerland

An altar table from the former Augustinian church in Fribourg (Switzerland) was studied by means of neutron and X‐ray imaging to investigate the embedded reliquary. The neutron transmission images showed that the sepulcrum contained three objects showing high contrast and high attenuation. As the particles were almost invisible in the X‐ray image, it was assumed that they were organic material. Comparative measurements on reference samples of materials possibly contained in such a reliquary (bone, teeth, leather, incense and parchment) suggest that the particles are bone fragments. Besides an assessment of the content, the results from the neutron investigation allowed a proposal of the probable geometry (i.e., shape and dimensions) of the sepulcrum.     

CHARACTERIZATION OF ARCHAEOLOGICAL AND IN SITU SCOTTISH WINDOW GLASS

Scottish window glass from both archaeological sites and historic buildings was examined using portable X‐ray fluorescence (pXRF) and scanning electron microscopy – energy‐dispersive X‐ray micro‐analysis (SEM–EDX). The elemental composition of the glass provides information regarding the materials used and, subsequently, an approximate range of dates of manufacture. pXRF is shown to be more vulnerable than SEM–EDX to the effects of surface corrosion and matrix effects in archaeological samples. The study showed that the production of window glass in Scotland from the 17th century onwards appears to closely parallel that in England. It also demonstrated the potential of pXRF for in situ studies of window glass in historic buildings. pXRF was used to assess two Scottish buildings; one in state care and one in private ownership. The building in state care, the Abbot's House at Arbroath Abbey, showed a uniform glass type, suggesting that the building was re‐glazed completely at some point during the late 19th or early 20th century. The building in private ownership, Traquair House, had a range of glass types and ages, demonstrating a different maintenance and repair regime. This type of data can be useful in understanding historic buildings in the future, particularly if re‐glazing is being considered.     

NORTH APULIAN COARSE WARES AND FINE PAINTED WARES: A REAPPRAISAL ACCORDING TO NEW DATA FROM HERDONIA AND CANUSIUM

Late Antique coarse cooking wares and painted fine wares found at Herdonia (second half of the fourth century to mid‐fifth century ad ) and Canusium (late sixth century to early seventh century ad ) have been chemically and mineralogically characterized. A total of 74 samples (40 of coarse ware and 34 of fine painted ware) was investigated through optical microscopy, scanning electron microscopy, X‐ray powder diffraction, inductively coupled plasma optical emission spectrometry, inductively coupled plasma mass spectrometry, neutron activation analysis and X‐ray fluorescence. A new statistical method, namely the classification tree methodology, was used for the treatment of geochemical data. The characterization of the Herdonia and Canusium assemblages was combined with a review of earlier results obtained for San Giusto and Posta Crusta, in order to get an insight on Late Antique ceramic trades in northern Apulia. It appears possible to reconstruct a production pattern organized at multiple production sites, both rural and urban, that exploited similar raw material deposits, specialized in certain productions, and commercialized products at different geographical scales. Imports from outside northern Apulia may be identified for coarse wares. A likely area of production is difficult to establish; however, the northern Adriatic coast and the area of Greece may be suggested.     

LEAD ISOTOPIC ANALYSIS FOR THE IDENTIFICATION OF LATE BRONZE AGE POTTERY FROM HALA SULTAN TEKKE (CYPRUS)

Lead isotopic compositions were measured for 65 sherds from five pottery wares (Plain White, Coarse, Canaanite, White Slip and Base‐ring) excavated from the Late Bronze Age site of Hala Sultan Tekke (Cyprus). The elemental composition and isotopic signature of the sherds were compared with those of 65 clay samples collected in south‐east Cyprus, mainly in the surroundings (<20 km) of Hala Sultan Tekke. This work shows the effectiveness of using lead isotopic analysis in provenance studies, along with other analytical techniques, such as X‐ray diffraction (XRD) and a scanning electron microscope (SEM) equipped with an energy dispersive X‐ray detection (EDX) facility, to identify the composition of pottery wares and the clay sources used for pottery ware production.     

THE TECHNOLOGY OF ‘GLAZED’ RESERVED SLIP WARE—A FINE CERAMIC OF THE HARAPPAN PERIOD*

‘Glazed’ Reserved Slip Ware (RSW) is a high‐quality glossy bichrome pottery of the Indus Valley civilization, and dates to the mature Harappan period (c. 2600–1900 bc ). Scanning electron microscopy with energy‐dispersive X‐ray analysis indicates that the surface coat on RSW is composed of a pale grey vitrified clay slip, which overlies a black slip with significantly higher iron oxide. Hence the term ‘sintered’ Reserved Slip Ware is to be preferred. X‐ray diffraction analysis indicates that both the pale and black slips contain hercynite, mullite and quartz, but observation by scanning electron microscopy shows that the black slips contain higher amounts of coarser‐grained hercynite. The elemental data suggest that different clays were used to make the bodies and the slips. However, key element ratios are very close in associated black and pale slips. The grey slip may have been produced by elutriation of the fine, iron oxide‐rich clay that was used to prepare the black slip. The pale grey slip was laid over the black and removed by combing to produce a bichrome effect, which evoked semi‐precious materials such as agate. RSW was a specialist product that required significantly higher input skill and resources than the majority of Harappan clay‐based ceramics. It is a further example of the range of sophisticated Harappan ceramic wares, which included faience, fired steatite and stoneware.     

THE CHEMICAL COMPOSITION OF SOME ARCHAEOLOGICALLY SIGNIFICANT FLINT FROM DENMARK AND SWEDEN

Flint was one of the most widely employed raw materials for artefact manufacture in Denmark and Sweden during the Stone Age, and it continued to be used during subsequent periods. Prehistoric flint mining and lithic manufacturing studies in these countries have attracted considerable attention, but there have been no recent attempts to chemically characterize the geological source materials. This paper builds on a pilot study ( Hughes et al. 2010 ) and uses energy‐dispersive X‐ray fluorescence (EDXRF) analysis to determine quantitative composition estimates for nine major, minor and certain trace elements in seven archaeologically significant flint sources in Denmark and Sweden, along with new data on a number of other sources of prehistoric significance. These data provide a geochemical foundation for ongoing research devoted to determining contrasts and continuities in the time and space utilization of flint sources in Scandinavian prehistory.