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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]

This paper presents the results obtained from the thermal analysis of a set of geomaterials (clays, pyroclastic materials, and industrial recycled materials) to be used as raw materials for the synthesis of geopolymers, specifically designed for the conservation of Cultural Heritage (CH) buildings, particularly in seismic hazard zones such as Sicily. X-ray diffraction and gas volumetric analysis (calcimetry) were applied to this set of raw materials in order to characterize the materials from the chemical and structural point of view. Thermogravimetric analysis (TG), TG coupled to Fourier transform infrared spectroscopy (TG-FTIR), and differential scanning calorimetry were used to characterize their thermal behavior. The statistical treatment of the thermogravimetric data by principal component analysis and hierarchical clustering analysis highlights the direct relation between the thermal data and the material composition that will be exploited for the selection of the best materials to obtain geopolymers specifically designed for the conservation of CH buildings. [ABSTRACT FROM AUTHOR]

Zeolites are present in numerous outcrops of volcanites of different ages in Sicily (Italy). Some of these outcrops are important because they constitute the ideal genesis conditions of some of these minerals, which represent geological indicators of chemical and geothermal gradients involved during their formation. For this purpose, a group of zeolites coming from areas of the Ionian coast and Palagonia village (Eastern Sicily) was investigated by means of Raman spectroscopy. In the geological record, these areas have been influenced by intense volcanic events that produced mineralization of hydrothermal origin. Sicilian zeolite samples were analysed in situ using different mobile Raman apparatus, directly on the outcrops of Aci Castello and the nearby Lachea Island, or in local collections where they are preserved. Some of these samples have been then analysed using laboratory micro‐Raman to compare the results and identify the zeolite types. The strength and weakness points of each instrument have been highlighted. Often, the Raman spectra of zeolites are affected by broad fluorescence, making them of difficult interpretation. However, satisfying results were obtained with portable devices, whose identifications were confirmed by micro‐Raman, discerning zeolites of different groups, such as analcime, chabazite, natrolite and phillipsite. The use of portable instruments has demonstrated the possibility to obtain identification of zeolites and related minerals both on site and in the laboratory, whose results match with the geological setting of the considered areas. [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]

The results of a petrographic and geochemical study carried out on archeological grindstones allow to provide new constraints on protohistoric commercial exchanges over the Mediterranean area. Eleven grindstones, discovered in an archeological site located in Milazzo (Messina, Sicily) and dated from the Early Bronze Age, have been investigated by geochemical and petrographic techniques. The raw materials are mainly volcanic rocks characterized by calc-alkaline and K-alkaline affinities with volcanic arc geochemical signature. Only one sample, made of basalt belonging to the Na-alkaline series, shows an intraplate signature. The comparison with the available literature data for similar rocks allowed constraining the volcanic origin of the exploited lavas. While the intraplate-type raw material came from Mt. Etna Volcano (Sicily), the arc-type volcanic rocks are mostly trachyandesites, basaltic andesites, and one rhyolite. Although most of them come from the Aeolian Arc, a provenance of some samples from the Aegean Arc cannot be excluded. This last region could represent the most probable provenance area for the rhyolite sample. [ABSTRACT FROM AUTHOR]

Blackening and disaggregation of exposed surfaces of stone monuments are well-known effects of stone decay taking place in polluted urban environments all over the world. This paper aims to assess the contribution of natural and anthropogenic sources of total suspended particulate (TSP) causing permanent damage (black crusts) to the stone monuments of Catania (Sicily), one of the most popular 'cities of art' of southern Italy. Atmospheric pollution of Catania, a typical Mediterranean coastal town, is mainly contributed by vehicle exhaust emissions rather than industrial ones. Episodically, the city also suffers gaseous and ash emissions (plumes) from the nearby Mount Etna volcano. Thus, to discriminate between natural and anthropogenic contributions to stone decay on Catania monuments, black crusts and TSP were sampled within the urban area and subjected to specific analytical procedures (optical microscopy, X-ray powder diffraction, Fourier transformed infrared spectroscopy, scanning electron microscopy equipped with energy dispersive spectrometry, ionic chromatography and dual inlet mass spectrometry). Mineralogical, chemical and isotopic characterization of black crusts and TSP provided new insights concerning the partition of sulfate sources in this particular urban context. The influence of Mount Etna emissions on both TSP and black crusts compositions was shown. Nevertheless, the key role of anthropogenic sources in the total sulfate budget was confirmed, while sea spray and volcanic emissions were found to make subordinate contributions. Quantitative data useful for the identification of the threshold pollution levels for preventive conservation of Catania monuments were obtained. [ABSTRACT FROM AUTHOR]

Abstract: This work focuses on the petro-archaeometric analysis of several transport amphorae dated back from 4th to 2nd century BC which were found in various archaeological excavations recently carried out in Messina and Milazzo (north eastern Sicily). These amphorae, generally known as Graeco-Italic, raise the problem of the identification of their production areas. Petrographic analyses proved the presence of two groups characterised by the presence of coarse metamorphic or volcanic inclusions and one group with finer metamorphic inclusions. Multivariate statistical analyses made it possible to detect the production area of the amphorae with metamorphic inclusion in north eastern Sicily, comparing them with locally produced bricks and clay sediments cropping out near the ancient cities. On the contrary, the studied amphorae rich in volcanic inclusions have petrographic and chemical features which can be attributed to production areas in the Campanian region. [Copyright &y& Elsevier]

Noto is an important Baroque urban center in south-eastern Sicily, which was completely reconstructed after the severe earthquake of 1693. Most of its monuments and historic buildings were built in Pietra di Noto stone, a pale cream calcarenite, quarried in outcrops located near the city. This stone, still currently used as building material, is undergoing many forms of alteration and degradation, which cause significant damage to monuments. In this study, three commercial protective products were tested on some Noto calcarenite samples from quarries, with the aim of assessing their protective effectiveness. In particular, petrographic analyses by optical microscopy were carried out for textural characterization of the stone materials. Capillary water absorption, porosimetric and colorimetric procedures, UV radiation and salt crystallization aging tests were performed to better evaluate interactions between protective products and substrate. [ABSTRACT FROM AUTHOR]

The Cathedral of St. Giorgio in Ragusa Ibla (Sicily) is one of the most important Baroque monuments of eastern Sicily. The restoration of the monument underway has put forward notable questions regarding the stone materials used and their state of degradation. The façade appears to be made mainly of a creamy white calcarenite, and of mortars and plasters. However, detailed analysis has highlighted a more complex use of the raw material. The mortar and plaster have a different composition in regards to their architectural use while the natural stone material is distinguished not only by a creamy-white calcarenite but also by a dark coloured bituminous calcarenite (pitch rock), which now appears whiter because of superficial chromatic alterations. This process was reproduced in the laboratory using an accelerated aging technique on samples of bituminous calcarenite, which allowed the cause of the alternation to be identified as photo-oxidation of the asphaltenes. Following this process of photo-oxidation, other forms of chromatic alterations affected the façade (brown–orange-coloured patinas). FTIR, Scanning Electron Microscope and thin section microscopic observation allowed the characterization of also the products of this process to be carried out, highlighting the complex mechanism which the processes underwent. [ABSTRACT FROM AUTHOR]

An archaeometric study of the stone materials employed in the Late Baroque historical monuments of the ancient city centre of Catania was carried out. Lithological maps of a selection of monuments, transferred to a digital format, revealed that the stone materials are both magmatic and sedimentary rocks, the colours of which are matched in a peculiar type of bichromy. Particular attention focused on sedimentary rocks, which consist of various types of limestone quarried near the city of Syracuse (Hyblean Plateau, south-eastern Sicily). Carbonate rocks were characterised in terms of mineralogy, petrography and geochemistry, by studying rock samples from both monuments and historical extraction sites. Results showed that, although only one name was historically attributed to the above lithotypes (i.e. “Pietra di Siracusa‘’), they were quarried from many locations and, as they belong to various geological formations, they therefore exhibit great variety. In order to examine the durability of Hyblean limestones employed in works of cultural heritage interest, salt crystallisation tests were carried out according to standard procedure norms (UNI EN 12370 () Determination of resistance to crystallisation of salts, 6p). Results are consistent with the forms of deterioration observed in the monuments, and highlight the close relationship between textural characteristics and damage. Our purpose is to provide a basic tool, which may be useful both for conserving monuments of cultural heritage and for their restoration. [ABSTRACT FROM AUTHOR]

In this work, we focused on the possibility of using clay sediments found in Sicily as precursors to produce alkali activated materials (AAMs) with properties comparable to those of traditional materials used in construction. Two different clays were selected: Plio-Pleistocenic marly clay (PP) and Numidian Flysh clay (NU) to test the use of sediments with and without calcite. AAMs were prepared using precursors thermally treated at 700 °C and alkaline activator solutions as NaOH 4, 6 and 8 M with or without sodium silicate. All samples were cured at 85 °C for 20 h and at room temperature for 28d. Mineralogical analyses, FTIR data, SEM/EDS morphological and chemical observations showed the formation of a polycondensed gel after 20 h. AAMs obtained from calcite-rich clayey sediments (thermally treated) achieved good compressive strength after 28 days with all activators. However, AAMs based on thermally treated calcite-free clays only showed good compressive strength development only when activated with 8 M NaOH and sodium silicate. • Clay sediments from Sicily have been used as precursors for the production of alkali-activated materials (AAMs). • The calcite-bearing precursor are more suitable for AAM production. • The XRD analysis revealed a relative amorphous band indicating the presence of an amorphous phase. • The gel appears as a multi-component system dominated by an (N,C)-A-S-H composition and also shows N-A-S-H or C-A-S-H gel. • Mechanical strength shows excellent results in samples activated with NaOH 8 M and sodium silicate. [ABSTRACT FROM AUTHOR]

Abstract: This work is focused on the petro-archeometric characterization of the fine pottery production of the archaeological site of Gela (Sicily). Thirty-five samples coming from three Archaic and Hellenistic kilns and five coming from an Hellenistic house, were investigated by means of optical microscopy, XRD and XRF analysis. With the exception of some ceramics which are undoubtedly imported, all the samples have similar petrographic features, but on the basis of chemical composition, we can distinguish two different groups. The presence of two local productions is confirmed by the comparison with locally outcropping sediments and with archaic and modern bricks of sure Geloan production. This result is particularly significant for the definition of reference groups of this wealthy polis that played an important trading role in the Mediterranean area. [Copyright &y& Elsevier]

The mineralogy and chemical compositions of shale and sandstone alternations of Cretaceous age of the Monte Soro Unit, Sicily, have been determined. The clay minerals in the shales are mostly illite and I-rich mixed-layer I/S reflected by enrichment in Al2O3, K2O, and chemically similar elements. The sandstones are subarkose to quartz arenite. The shales and sandstones have upper-crustal rare earth element patterns, and except for K2O, they are depleted in alkaline and alkaline-earth elements as a result of intense weathering. The sandstone and shale mineralogy suggests a diagenetic history in which the sediments were subjected to temperatures in excess of 100°C, during which interaction between some minerals in the shales and sandstones took place. Thus, diagenetic quartz cementation and feldspar alteration in the sandstones and smectite illitization in the shales occurred together with the shales being a sink for potassium and the sandstones a sink for silicon. Negative europium anomalies (Eu/Eu* between 0.45 and 0.87), (Gd/Yb)ch ratios (<2, except for sample Cl), and Sc/Cr versus La/Y and La-Th Sc diagrams suggest that the sedimentary rocks were derived from post-Archean granitoid-like rocks in a tectonically stable area. In addition, the foliated fabrics of polycrystalline quartz grains and the abundant phyllite rock fragments indicate a provenance from metamorphic rocks. The study of several trace element ratios (Ti/Zr, Cr/Zr, Y/Ni, Cr/V, Zr/Tb, La/Tb, La/Tb, Cr/Th, Zr/Hf, Zr/Yb, Yb/ Hf, V/La, La/Yb) strongly supports a local derivation from the European paleomargin. [ABSTRACT FROM AUTHOR]

Abstract: Mineralogical (X-ray diffraction) and geochemical (X-ray fluorescence) compositional data of Alpine Tethyde mudrocks from Sicily were used to unravel the interplay of provenance and diagenesis by means of multivariate statistical methods (PCA, discriminant function analysis) designed for non-negative constant-sum data. The Sicilian Alpine Tethydes comprise Cretaceous–Eocene scaly shales (Mt. Soro and Upper Scagliose Shales Units), Eocene–Oligocene variegated shales (Troina and Nicosia Units), and Miocene Numidian shales (Nicosia Unit). The use of biplots of clr-transformed variables allows discrimination of two different groups of shales. High CIA values reveal a strongly weathered source area especially for the Numidian shales. The analyses of mixed-layered clay minerals indicate that the behaviour of K2O and geochemical affine elements is controlled by the diagenetic grade, which increases from south-west to north-east in response to tectonic loading. Ratios of selected elements (Zr, Y, La, Nb, Ti, Co, Cr, Ni), considered essentially unchanged with respect to the source rocks, are similar in the scaly and variegated shales, and resemble the Variscan Peloritani metamorphic basement. In contrast, the distinct geochemical signature of the Numidian shales reveals a source similar to the average cratonic sandstone, suggesting derivation from external sources located in the foreland. Multivariate discriminant analysis performed on selected trace elements confirms the previous suggestions. [Copyright &y& Elsevier]

• Binary mixtures with pyroclastic deposits (Mt. Etna volcano) and metakaolin. • Alkaline activating solutions based on Na or K cation. • Polycondensation reaction monitoring on fresh pastes through In situ FTIR analysis. • Performance in terms of structure, compressive strengths and porosity. The huge availability of volcanic deposits in Mt. Etna volcano and the wide use of volcanic materials as aggregates in local architecture encouraged us to apply them in alkaline environment to produce geopolymeric binders to restore historical buildings of Mt. Etna area. Two clusters of samples for each volcanic precursor (volcanic ash and ghiara paleo-soil) were produced, using 10 and 20% wt. of metakaolin and two different alkaline solutions based on sodium and potassium respectively. A comparative study was made in relation to activators used, focusing on evaluation of polycondensation step (in ATR); chemical and structural characterization (FT-IR); TGA analysis, qualitative XRD analysis and mechanical compressive test after 7 and 21 curing days. ATR results confirmed the occurrence of geopolymerization for all samples; FT-IR analysis showed a higher content of carbonates in potassium-samples, decreasing at increasing of metakaolin content. A low weight lost was recorded in consolidated samples, as well as a partial dissolution of volcanic phases. Higher mechanical compressive strengths for K-samples, reaching 89 MPa as highest value after 21 days, differently to sodium-samples (51 MPa) were recorded, reflecting the porosity of the different specimens. [ABSTRACT FROM AUTHOR]

Abstract: This paper is focused on a spectroscopic study of some pottery shards from an archaeological site in Syracuse (Sicily, Southern Italy), dating back to the Hellenistic–Roman period. Structural characterization was performed at different scales of observation, i.e. from macroscopic to mesoscopic. The main goal was to point out the potentiality of the small angle neutron scattering (SANS) technique as a non-invasive analytical tool in archaeometry, also in conjunction with other, more usual, methodologies. Correlation of experimental data, i.e. macroscopic typology and texture, obtained from petrographic analysis, and radius of gyration and fractal dimension of the interfaces of the mesoscopic aggregates obtained using SANS, together with mineralogical X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis, allowed hypotheses to be made on the production technology of the investigated samples. [Copyright &y& Elsevier]

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]