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The recent upgrading of synchrotron radiation (SR) sources has favored, in the last few years, the construction and design of beamlines optimized for the study of cultural heritage materials, which may require ad hoc setups, specific spatial resolutions, and detection limits. In the field of cultural heritage, integrated approaches combining different techniques are often required, even at large facilities, where some beamlines offer the possibility of performing different types of measurements at the same point of analysis, complementing preliminary information usually obtained by conventional laboratory and/or portable in situ methods. An overview of the last ten years of synchrotron applications for the study of pigments is given, with discussion of upstream and downstream challenges to methods and techniques. The possibilities offered by the synchrotron techniques are illustrated by a case study of a particular class of painted ceramics, as an example of different research questions that are solved by a combination of SR-based methods. [ABSTRACT FROM AUTHOR]

[Display omitted] • Combined non-destructive analytical approach using portable instrumentation • Complementary techniques and multivariate analysis allow characterization of pigments • Improved knowledge on pigments production, sourcing and use in 27 BC – 193 AD Rome Polychrome painted plasters from a suburban villa of Imperial epoch were recovered during the 1930s, and are currently exhibited in the galleries underneath the St. John in Lateran Church, Rome. As wall paintings from the Rome area are a rare find, and as the fragments were never subjected to conservation treatments, it was chosen to non-invasively characterize 113 coloured areas, representative of colours and decorative systems. The chemical and mineralogical information collected from this measurement campaign were interpreted in the light of archaeological context (i.e. the high status of the family who owned the villa , the different renovation works that affected it, the identification of decorative systems linked to such works), as well as of published data from contemporary wall paintings in the Rome area. A multi-analytical, non-destructive characterization of the painted surfaces was carried out in situ by means of portable Raman spectroscopy (pRS) and X-ray fluorescence (pXRF), in the framework of a wider project concerning the study of raw materials and paintings of archaeological interest. The combination of pXRF and pRS allowed to characterize the whole palette, as well as to discriminate among different pigments sharing the same key element, and to identify degradation issues. In this context, the use of principal component analysis gave an important contribution to the interpretation of data ant to the individuation and characterization of pigments such as ochres, green earths, lead based pigments, Egyptian blue, cinnabar, Tyrian purple. Calcium and magnesium carbonates are present, as expected, in the plaster, and are often associated with their sulphates and nitrates, and Ca-oxalates indicating degradation. Lead white and bone white have been used. Some peculiar yellow pigments have been identified, such as realgar/pararealgar and Naples' yellow, in addition to ochres. Hematite, minium and cinnabar were all identified, alone or in mixtures. The presence of the precious dye Tyrian purple is very likely, but could not be confirmed univocally. Green earths and complex mixtures of iron and copper compounds were detected. Egyptian blue was used, highlighting different production processes for this artificial glassy material. For the blacks, we hypothesize the use of carbon-based pigments. The obtained data confirms the general palette used by Roman painters, and sheds new light on the materials used in the Lateran area across two centuries, including their provenance and manufacturing. It appears that different earths and ochres were used diachronically, and that the owners could afford very expensive pigments, such as cinnabar and Tyrian purple. [ABSTRACT FROM AUTHOR]

An analytical investigation performed on Southern Italy pottery highlighted the usefulness of Raman spectroscopy to give answers to archaeological questions. It can provide important information concerning the production technology and raw materials constituting the glassy coatings. Raman spectroscopy was supported by Scanning Electron Microscopy coupled with Energy Dispersive X‐ray Spectroscopy (SEM‐EDS) for observations and elemental analysis. The studied samples, ranging from the 13th century lead‐tin‐glazed protomajolica to the 15th –16th enamelled pottery, come from the Castles of Montella and Ariano Irpino (Campania), from the castles of Scicli and Modica and from surveys carried out in Buscemi and Caltagirone (Sicily). Glassy matrices, opacifying agents, colour‐related raw materials and body‐coating interface crystalline phases were investigated. Though the coatings resulted all typically lead‐rich glass types, lumps showing a different Raman profile suggested that at least in one case, the batch was adultered with recycled glass waste. Furthermore, samples coming from Montella, belonging to the three main classes of ceramics defined by archaeological hypothesis, could be grouped according to their cassiterite content. The crystallization of lead–potassium feldspars at the coating‐body interface in a group of samples was ascertained. With regard to the origin of colours, the spectra of blue coatings highlighted phases that can be traced back to the use of Co‐based and Co–As‐based raw materials, while turquoise decorations were found to contain malayaite. Highlights: Medieval and renaissance pottery from Southern Italy were analysed.Raman analyses provided unexpected results and answers to archaeological questions.SnO2 Raman bands confirmed the grouping of Montella samples in three classes.Neoformed phases due to reactions during the production processes were discovered.Different cobalt‐based phases were found in the blue enamels. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ochres are natural deposits enriched in iron oxides /hydroxides widely exploited for artistic purposes. • 16 ocher pigments (commercial and natural) were studied, including materials from the Røros (Norway) district. • The study aimed to define the origin of the ochre pigments used at the UNESCO World Heritage site of Røros (Norway). • A multi-analytical approach (colorimetry, XRF, vibrational spectroscopies, and XRD) was used. • PCA of IR data played a key role in interpreting spectra and other ambiguous analytical results. Ochres are natural deposits particularly enriched in iron oxides and hydroxides giving them their typical colours spanning from bright red to yellow or brown. For this reason, they have been widely exploited over millennia for artistic purposes, becoming among the most known pigments. A series of 16 iron-based powder pigments including both commercial and natural ochres was investigated. Specifically, natural materials came from the Røros (Norway) district, where they were historically extensively used for painting the wooden houses' facades. The set of samples was studied by applying a multi-analytical approach involving colorimetry, X-ray fluorescence, infrared spectroscopy in multiple spectral ranges and configurations, Raman spectroscopy, and X-ray diffraction. The potentiality of coupling infrared spectroscopy with Principal Component Analysis (PCA) in characterising and discriminating iron-based pigments represents an innovative approach to guide the interpretation of results obtained by applying a variety of analytical techniques, thanks to the identified clusters. This allowed, in turn, for depicting an extremely consistent description of the samples and specifically of those used in the conservation intervention of the UNESCO World Heritage site of Røros (Norway) and whose composition has never been studied before. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, an analytical characterization of painted plaster samples coming from ancient buildings dated back to 2nd cent. B.C., located in Licata (Sicily, Southern Italy), has been carried out. The investigation has been performed through different spectroscopic techniques: X-ray fluorescence (XRF) using an handheld energy-dispersive XRF analyzer, scanning electron microscopy equipped with an Energy Dispersive Spectrometry microanalysis detector (SEM-EDS) and Fourier transform infrared absorbance spectroscopy (FT-IR). The main goal is to identify the plaster and pigments material. In particular, the XRF investigation of surfaces is the first step for a preliminary elemental characterization. Then, through SEM-EDS measurements, a quantitative analysis of the chemical composition of the plaster and the pigmenting agents along with eventual components related to deterioration processes has been obtained. Finally, FT-IR absorbance spectra have proven to be a useful tool to investigate the molecular nature of the used materials. [Copyright &y& Elsevier]