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A series of early Byzantine glasses, recovered in Ganzirri (Sicily, Italy), was analysed for major, minor and trace elements. All the analysed fragments were found to be natron-based silica–lime glass. Concerning minor and trace elements, the samples can be divided into two groups: glass with high Fe, Ti and Mn contents ( HIMT glass) and glass with low levels of Fe, Ti and Mn. These results, strictly in agreement with literature data for glass of the Mediterranean region, can be interpreted as a consequence of the wide trade network established in this region and of the intense circulation of raw glass and artefacts from different Mediterranean areas. X-ray absorption spectroscopy studies at Fe and Mn K-edges, performed on HIMT glass, indicate that Fe is in the oxidized form while Mn is in the reduced form. [ABSTRACT FROM AUTHOR]

Abstract: We report the results of a study performed on several glass samples recovered after the destruction caused in Messina by the earthquake of 1908, and stored in the ‘Fiore’ deposit of the Regional Museum of Messina (Italy). The samples, still lacking a reliable classification, are glass cakes, some spare mosaic tesserae, and fragments of a well-dated mosaic (Mosaico dell’Angelo, XIII–XIV century A.D.). EPMA, SEM-EDS, XRPD and XAS were employed to provide a detailed chemical, mineralogical and spectroscopic characterization of the samples. The chemical analyses of major elements show high levels of K2O and MgO, as a result of the prevalent use of plant ashes as flux. The cakes are characterized by a large dispersion of Si, Al and Ca contents, suggesting the use of different starting raw materials. The most common crystalline phases used as opacifiers and colorants are quartz and wollastonite. Crystalline aggregates of SnO2 are present in the gray cakes, whereas PbSnO3 crystals are found in two green mosaic tesserae. All the red samples contain small clusters of metallic copper. On the basis of the chemical composition, it is possible to confirm that most of the samples were produced in the XIII–XIV century, while no specific conclusions were reached on the possible use of the glass cakes as raw glass materials for the production of the investigated mosaic tesserae. [Copyright &y& Elsevier]

Abstract: Optical, SEM-EDS and TEM microscopy, Mössbauer and UV–Vis spectroscopy, SIMS spectrometry and ICP spectroscopy, were carried out on sixty vitreous finds, with particular attention to the trace elements, in order to correlate them to the raw materials, the working instruments and the technology employed. The colours of these vitreous finds have been studied in detail to establish the presence and kind of chromophores, the redox conditions used for obtaining of the vitreous mass during the fusion process, the role of the oxidation state and chemical environment of the different metal ions, etc. Eight crucibles and one refractory material were also investigated by XRD diffractometry and TG-DTA thermogravimetry. Their composition, morphology and thermal behaviour gave information on the working temperature inside the kilns. These studies offer a scientific contribution to the archaeological requests to characterise correctly the pre-industrial glass manufactures in Valdelsa. The obtained results allow us to gain a more exhaustive knowledge of the production technology at Germagnana (14th century) and Gambassi (16th century) and of the provenance of the employed raw materials and to register differences and analogies in their production process. [Copyright &y& Elsevier]