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Thirty-two glass objects (third to ninth centuries ad) have been investigated by means of SEM-EDS, EMPA, ICP-MS and LA-ICP-MS. Siliceous sands and natron were identified as the vitrifying and the fluxing agents, respectively. Colouring agents were iron for yellow/-green, aqua blue and blackish glass; cobalt for blue and, combined with iron, for brownish glass; and copper and lead antimonates for one emerald green glass. Antimony was the main decolourizer, while manganese was rarely used or effective. Half of the collection was probably of Levantine origin, while the other half was assigned to the North African coast (Egypt?). The reliability of the CaO-rich HIMT glass group has been consolidated. [ABSTRACT FROM AUTHOR]

A collection of 30 ceramic samples, 16 of coarse wares and 14 of fine painted wares, have been investigated by optical microscopy, scanning electron microscopy, inductively coupled plasma optical emission spectrometry, inductively coupled plasma mass spectrometry and neutron activation analysis. Further samples of clayey sediments, both locally outcropping and found within the settling tank, have been submitted to the same analytical techniques for comparison with the ceramic collection. The results demonstrated that local clayey sediments were used as received for the production of coarse wares. The same raw materials were sieved and/or refined by decantation for the production of fine painted wares, which, in fact, provided results that were perfectly comparable with those for the clayey raw materials found within the settling tank. The Faragola productions were distinguished from the neighbouring Apulian productions according to petrographic features (the presence of leucite-bearing volcanic rocks and Mn-rich wads) and their bulk chemical composition. [ABSTRACT FROM AUTHOR]

The artistic evolution of the Volterran cinerary urns is a good representation of Etruscan painting from the fourth to the first century bc. The interest generated by this type of object directed our research towards the study of the Volterran artefacts, including the analysis of the pigments as well as that of the rocks used for the coffers. The entire colour range shown by the painted urns has been sampled and investigated through Raman microscopy and scanning electron microscopy. Rock samples were taken both from the urns and from outcrops in ancient carbonate rock quarries near Volterra, from where they may potentially have been sourced. A set of 30 samples was collected and submitted to stable carbon and oxygen isotope analyses. The results obtained showed that the pigments used for the decoration of the Volterran urns were basically constituted by red ochre, Egyptian blue, carbon black and gypsum. The identification of lead-based pigments and barium sulphates further informed us about old restorations undergone by several urns. As far as the provenance issue is concerned, the isotopic data indicate that the rocks used for the four urns were favourably comparable to those outcropping at Pignano, while two other urns were more similar to those sampled along the Elsa River at Colle Val d' Elsa. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Ceramic coatings on ancient pottery, in particular black gloss, transparent glaze (first alkali based and then lead based) and opaque glaze (enamel) up to the lustre decoration, can be considered as the top technological skill of ancient ceramists. Indeed, their production demands the ceramist a thorough knowledge of pyrotechnology, including the ability to strictly control furnace atmosphere conditions. Several papers have dealt with the study of ceramic coatings, aiming to reconstruct the production technology and the modality of application and to define the relations between coating and ceramic body. These tasks are quite difficult to accomplish, also due to the very fine details of these surface layers. A multianalytical approach is therefore necessary, including conventional (scanning electron microscopy-energy dispersive spectrometry, electron probe microanalyser and Raman) and high resolution techniques (high resolution TEM, synchrotron radiation source based diffraction and X-ray absorption spectroscopy). Two case studies on different ceramic coatings are presented: black gloss pottery from Northern Etruria and Sienese 'Archaic' majolica from Tuscany. [ABSTRACT FROM AUTHOR]

The present work was aimed at characterising the materials and assessing the state of conservation of the 'Adorazione dei Magi', a wooden panel painted by Bartolo di Fredi in the second half of fourteenth century. To this goal, innovative non-destructive investigation techniques such as portable Raman spectroscopy, visible reflectance spectroscopy and unilateral nuclear magnetic resonance, were used in situ in order to achieve surface and bulk compositional data. The former allowed the identification of the artist's palette including cinnabar, red ochre, minium, carbon black, lead white, ultramarine blue, malachite and phthalocyanine green, while the latter provided information on the stratigraphic structure and state of conservation of the wooden panel. [ABSTRACT FROM AUTHOR]

A total of 22 samples were taken both from plasters still in situ and from collapsed material recovered by French, Italian and Moroccan teams at the Roman settlement of Thamusida (Rabat, Morocco). The sample characterization was obtained using optical microscopy, scanning electron microscopy, image analysis and Raman micro-spectroscopy. Plaster aggregate was made using a mixture of sands and clays that outcrop nearby, while lime was probably produced using the local limestone crust, as was further verified for the mortars. The plasters from the bath complexes (public buildings) and the Temple à trois cellae (sacred building) were very poorly made, while those from areas VII and XX (private buildings) indicated the involvement of more expert masons. The pigments used were cinnabar, red ochre, yellow ochre, Egyptian blue, green earth, chalk white and carbon black. The overall manufacture was of low quality, and hence perfectly comparable to that observed in other Roman Provinces. With respect to Italy and to other Mediterranean Roman sites, Thamusida fits well within an aesthetic and technical koinè that differentiates sites of the Italian peninsula from those in the Provinces. [ABSTRACT FROM AUTHOR]

Twenty-six tesserae (red, orange, yellow, light amber, green, blue and white) from the balneum of the villa at Faragola (Ascoli Satriano, Foggia) have been examined by colorimetry, ICP-MS, ICP-OES and SEM-EDS. Different types of calcareous sands have been used as the source of silica (network former), also providing the stabilizing agent. A natron-type soda source served as the network modifier; however, the use of a sodium-rich plant ash and the recycling process have been hypothesized for the production of two tesserae (FT 1 red and FT 3 orange). The colouring and opacifying agents were Cu oxide (cuprite, orange), metallic copper (red), Pb antimonates (yellow), Ca antimonates (white), a mixture of copper (Cu2 +) and Pb antimonates (green), a mixture of cobalt (Co2 +) or copper (Cu2 +) and Ca antimonates (blue). The light amber tesserae should owe their colour to iron (Fe3 +) alone or associated with sulphide (S2−) and Ca antimonates. It is likely that the Faragola tesserae were locally produced in a secondary glass workshop. [ABSTRACT FROM AUTHOR]

Analyses at the Cu–K, Fe–K and Mn–K edge were performed to study the green, marbled (green and yellow), blue and blackish (deep greyish olive green) glass slabs decorating three sectilia panels from the archaeological site of Faragola. Results indicate that all slabs were made by mixing siliceous sand with natron, sometimes probably mixed with small percentages of plant ash. Cu2 + and Pb antimonates should be responsible for the opaque green colours. The dark green and yellow portions of the marbled slabs are respectively comparable to the slabs comprising only one of these colours. Cu2 + together with Ca antimonates probably produced light blue slabs, whereas cobalt was used to produce dark blue slabs. We consider it possible that the abundance ratio of Fe2 +/Fe3 + and the complex Fe3 +S2 − would have an effect on the blackish slabs. The contribution of Mn cannot be ascertained even if it could have played a role in darkening glass colour. The comparison between the chemical composition of Faragola samples and several glass reference groups provided no conclusive evidence of provenance; whereas, the presence of a secondary local workshop can be hypothesized. [ABSTRACT FROM AUTHOR]

The aim of the present study is to reconstruct the production technology of Sienese ‘archaic’ majolica in the early decades of the 14th century ad. The integration of archaeological data with archived data revealed the presence of numerous workshops, suggesting that the Sienese tradition of majolica production was well developed up until the end of the 16th century. Sixty-seven uncoated and coated waste products were analysed. The ceramic bodies were examined by OM, XRDp, SEM–EDS, XRF, ICP–OES, ICP–MS and INAA. The coatings (enamels and glazes) were analysed by SEM–EDS and Raman microspectroscopy. The results showed that ceramics were rejected due to poor control of the firing temperature (technological wastes), faulty production technology (wastes of uncertain classification) and accidents (post-firing wastes). Finally, the analyses revealed extreme homogeneity of the ceramic bodies, indicating the continued use of the same raw material over the whole period studied. [ABSTRACT FROM AUTHOR]

In the Transangarian region of the Yenisey Ridge in eastern Siberia (Russia), Fe- and Al-rich metapelitic schists of the Korda plate show field and petrological evidence of two superimposed metamorphic events. An early middle Proterozoic event with age ofc.1100 Ma produced low-pressure, andalusite-bearing assemblages atc.3.5–4 kbar and 540–560 °C. During a subsequent late Proterozoic event atc. 850 Ma, a medium-pressure, regional metamorphic overprint produced kyanite-bearing mineral assemblages that replaced minerals formed in the low-pressure event. Based on the results of geothermobarometry andP– Tpath calculations it can be shown that pressure increased from 4.5 to 6.7 kbar at a relatively constant temperature of 540–600 °C towards a major suture zone called the Panimba thrust. In order to produce such nearly isothermal loading of 1–7 °C km −1, we propose a model for the tectono-metamorphic evolution of the study area based on crustal thickening caused by south-westward thrusting of the 5–7 km-thick upper-plate metacarbonates over lower-plate metapelites with velocity ofc.350 m Myr−1. A small temperature increase (up to 20 ± 15 °C) of the upper part of the overlapped plate is explained by specific behaviour of steady-state geotherms calculated using lower radioactive heat production of metacarbonates as compared with metapelites. The suggested thermal-mechanical model corresponds well withP– Tpaths inferred from obtained thermobarometric data and correlates satisfactorily withP– Ttrajectories predicted by other two-dimensional thermal models for different crustal thickening and exhumation histories. [ABSTRACT FROM AUTHOR]

Examines a microinclusion assemblage occurring in garnet and rutile on a graphitic metapelite from northeast Sardinia. Observation of paragenetic sequence and mineral composition for entire rock; Specification of component saturation hierarchy permitting thermodynamic projection through variable composition; Effect of progressive metamorphism on fluid content.