This work reports the results of an archaeometrical investigation of opaque Roman glass and is mainly focussed on the role of configuration and oxidation state of copper on the colour and opacity of red and green opaque finds (mosaic tesserae, game counters, and glass artefacts) from Sicily and Pompeii excavations. The glass fragments were characterised by EMPA, SEM-EDS, TEM, and XRPD analyses and the copper local environment was investigated using X-ray absorption spectroscopy. The analyses of high-resolution Cu-K edge XANES and EXAFS spectra suggest that, in red samples, copper is present as monovalent cations coordinated to the oxygen atoms of the glass framework, accompanied by metallic clusters. In green samples all the copper cations are incorporated in the glass matrix.

This paper presents the chemical characterization of 79 fragments of Archaic and Hellenistic fine‐grained pottery from archaeological sites in Messina, Catania, Lentini and Siracusa (Sicily). The sherds were classified as ‘calcidian’, ‘banded’, ‘unvarnished’ and ‘black varnished’ pottery. The major and trace elements identified by X‐ray fluorescence (XRF) were statistically elaborated using the method proposed by J. Aitchinson in 1986 for the analysis of compositional data. From cluster analyses using element/SiO2 log‐ratios, it was possible to group the pottery found in Catania, Lentini and Siracusa into highly linked clusters. Conversely, the Messina pottery was divided into two clearly distinct groups. With the aim of identifying any possible mineralogical differences between the two Messina groups, Fourier transform infrared (FT–IR) absorption measurements were made, showing only quantitative differences in plagioclase and muscovite. The specific groups of pottery with restricted chemical compositions are considered to be of local production, also on the basis of archaeological and petrographic evidence.

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.

Complementary studies on the inorganic chemical composition of Nerium oleander leaves collected in the town of Messina (Sicily, Italy) and seven grain-size fractions of local roadway dust have been carried out. Data and maps are presented to show that the particulate matter present in the air of Messina contains trace elements significantly in excess with respect to the average continental earth crust. The anomalies follow the outline of the urban area, the highest concentrations of trace elements being observed where traffic density is highest. Chemical and isotopic analyses of both road dust and Nerium oleander leaves indicate that Pb contamination still characterizes roads with heavy traffic. In addition to Pb, other metals such as Pt, Pd, Sb, Au, Br, Zn, Cu, Mo, and Cd are significantly enriched in roadway dust, indicating their common anthropogenic origin, especially from traffic. SEM/EDS study of some roadway dust particles has shown the presence of gypsum probably of secondary origin, mixed particles formed by coagulation or gas-to-particle conversion, and porous spherical particles apparently emanating from combustion processes.

Mosaic tesserae, part of Roman villa floor decorations, from north-eastern Sicily and the Aeolian Islands, were analysed by means of micro-Raman spectroscopy and scanning electron microscopy-energydispersive x-ray techniques. Archaeologists considerate these 'villa' floor decorations (ranging from the 2nd century BC to the 4th century AD) as a stylistic product of North African workers or North Africanstyle design that were imported from abroad. Much attention is paid in the technology of glass making in order to understand the capability of local workers to produce the same glassy material. Since the other coloured tesserae are definitively recognized as polished limestones and/or calcscists of well-known Sicilian geological formations, the glassy materials could be hypothetically interpreted in the same way. Spectroscopic and mineralogical techniques were applied to the materials in order to define both the colouring and opaquening agents. Bindheimite (Pb 2 Sb 2 O 7 ), well known in past as 'antique yellow', was always found in both green and yellow glass tesserae, acting either as a colouring and/or an opacifier agent. Investigations were made in order to consider the possibility of local manufacturing techniques on the basis of widespread easy-to-find complex sulfide ore deposits in the area.