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The implementation of analytical techniques able to certify food quality and origin in a fast and non-destructive way is becoming a widespread need in the agri-food sector. Among the physical non-destructive techniques, X-ray fluorescence (XRF) spectrometry is often used to analyze the elemental composition of biological samples. In this study, X-ray fluorescence (XRF) elemental profiles were measured on tomato samples belonging to different geographical areas in Sicily (Italy). The purpose of this investigation was aiming to establish a protocol for in-situ measurement and analysis able to provide quality assessment and traceability of PGI agri-food products, specifically sustaining health safety and self qualifying bio-chemical signature. In detail, sampling was performed in one of the most tomato productive area of south-eastern Sicily (Pachino district), characterised by a relative higher amount of Organic Carbon and Cation Exchange Capacity, and compared with samples from other growing areas of Sicily, falling in Ragusa province and Mt. Etna region. Experimental data were analyzed in the framework of multivariate analysis by using principal component analysis and further validated by discriminant analysis. The results show the presence of specific elemental signatures associated to several characterizing elements. This methodology establishes the possibility to disentangle a clear fingerprint pattern associated to the geographical origin of an agri-food product. [ABSTRACT FROM AUTHOR]

In this contribution a non-destructive approach has been used aiming at investigating the chemical composition of 35 ceramic items belonging to the collections of the Regional Aeolian Museum "Luigi Bernabò Brea" in the Lipari Island (Sicily, Italy). Different vessel types have been selected for analysis, including aryballoi, kotylai, olpai, anforiskoi, oinochoai, and alabastra, belonging to the "Proto-Corinthian and Corinthian" ware classes. The items, dating back to the period comprised between the early eighth and the first half of the sixth century BC, come from two different archaeological sites in the province of Messina (Sicily), specifically the Istmo necropolis of Milazzo, in the northern Sicilian coast, and the acropolis and necropolis of Lipari, in the Aeolian islands. The chemical characterization of ceramics, carried out through portable X-ray fluorescence spectroscopy (pXRF), aimed at gaining information on the production area of examined items whose autoptic analysis pointed to Corinthian imports. The possibility of carrying out experimental investigations on the most ancient materials from the archaic necropolis of Milazzo and on fragments from Lipari, albeit limited to pXRF investigations, allowed to enrich the knowledge on the Corinthian production exported to western areas as well as to discriminate, no longer based solely on autoptic observations and stylistic evaluations, between Corinthian productions and "local" imitations. [ABSTRACT FROM AUTHOR]

Archaic Roman painted antefixes, architectural slabs and louteria from the Palatine Hill in Rome, Italy, were studied by non‐destructive and micro‐destructive methods: Portable X‐ray fluorescence (XRF), micro‐Raman spectroscopy, optical microscopy, scanning electron microscopy with energy‐dispersive spectroscopy (SEM‐EDS) and X‐ray diffraction (XRD). The investigation enabled the characterization of raw materials and ceramic technology, providing insights on provenance. In fact, similarities were recognized with terracottas from the neighbouring Etruscan Veii. The analysis of pictorial layers revealed the use of Fe‐ and Mn‐based pigments, as well as the identification of more precious pigments on worthy pieces. The research intended to support the archaeological discussion about the frame of the nascent city of Rome, also in relation to the coeval Etruscan culture. [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]

This research is concerned with the investigation of Egyptian and Egyptianizing artifacts dating back to the period comprised between the 10th century BC and the first half of 6th century BC, which were found in some archaeological sites of eastern-central Sicily. The examined Aegyptiaca include thirt-four items consisting of scarabs, funerary statuettes, figurines and unguentaria, which are mostly preserved at the regional archeology museum "Paolo Orsi" in Syracuse and, only in part, at the regional Aeolian museum "Luigi Bernabò Brea" in the Lipari island. Some of the investigated objects are made of faience (a glazed non-clay ceramic material, coated with an alkali-based glaze), while some others are in steatite or other stones. Through the chemical investigation of the selected artifacts, the study aims to extend the compositional dataset available on Aegyptiaca, as well as to identify the colorants used for the preparation of the investigated glazes. For such a scope, non-destructive bulk chemical analyses through portable x-ray fluorescence spectrometry (pXRF) were carried out on both the bodies and the overlying coloured glazes. A rather variable chemical composition was found in terms of both bodies and glazes, thus pointing to the use of different recipes and/or workshops for the investigated artifacts. The results obtained demonstrate the validity of this analytical technique in revealing the elemental composition of artifacts belonging to museum collections. [ABSTRACT FROM AUTHOR]

[Display omitted] • Corning glass references were analyzed with diffuse reflectance IR spectroscopy. • DRIFTS was applied non-invasively to real cultural heritage mosaic glass tesserae. • The answers of DRIFT spectroscopy about cultural heritage glass were assessed. • DRIFTS results on glass tesserae are in accordance with pXRF and SEM-EDS ones. Within vibrational spectroscopy techniques, Raman is much more employed than infrared spectroscopy for the study of glassy materials belonging to cultural heritage. This could be due to both a less straightforward interpretation of the spectra and a more difficult application of the technique with portable instrumentations. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) can be exploited in archaeometric investigations because portable and non-invasive. On the other hand, no systematic applications of this technique to historical glasses are found in the literature. This exploratory work reports the DRIFTS investigation of the Corning Archaeological Reference Glasses, widely used as references in the cultural heritage field, and of real case glass samples, with the aim of exploring the potential of this technique to gain information about their composition and alteration. The results, exploiting the association of portable X-ray Fluorescence (pXRF), and, where possible, of EDS microanalyses, are encouraging, setting the samples within a compositional range and highlighting spectral differences for the altered surfaces. [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]