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ABSTRACT The non-invasive ultrasound propagation technique was applied in laboratory tests with the purpose to evaluate the susceptibility to decay of stone materials. The 'Scicli' limestone was chosen as test [...]

ABSTRACT The Palazzolo Formation calcarenite, commonly known as ''Pietra di Nora', has been widely used in the late Baroque monuments of the Val di Nora area. In this work, two [...]

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The development of post-medieval archaeology has been uneven in the Mediterranean. While major advances have been made in areas, such as the Aegean and Italy, others have garnered little sustained archaeological interest. In Malta, one of the principal barriers to the development of post-medieval archaeology has been the lack of knowledge and published findings regarding one of the most important find-types: pottery. The present study presents the results of the first archaeometric (chemical and minero-petrographic) analysis of post-medieval pottery in Malta, which sheds light on the changing ceramic relationships between Malta and Sicily during the 17thto early 20thcenturies. The results demonstrate that, on the one hand, locally-made Maltese pottery remained important throughout the post-medieval period, as did pottery from the Messina Straits area. While, on the other hand, pottery from the Syracuse area can be shown to be linked to the activities of the navy of the Knights of St John.

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.

The excavations at Mount San Paolillo (Catania, Italy) led to the discovery of a Prehistoric site that still represents the most important evidence of Middle and Late Bronze Age settlement in this area. During the excavations, archeologists located a hut, a store for ceramic storage vessels, and a pottery workshop, all of which provided a large quantity of heterogeneous ceramics with apparent typological parallels in other areas of Sicily, such as Syracuse, Augusta, and Messina. A large number of specimens were selected in order to cover all the macroscopic types and the main classes. The results identified four petrographic fabrics. Most of the ceramics are characterized by abundant tempers consisting of volcanic rock fragments and occasionally of grog. Only a few samples contained common fine-grained quartz. The groundmass ranges from non-micaceous to very micaceous. In some cases, there is evidence of mixed clays. Analysis of the chemical composition of the ceramics revealed the existence of two groups with low and high CaO contents. The high Fe2O3content (more than 8.7 wt%) is probably due to the use of temper from altered pyroclastic rocks which are of local provenance as SEM-EDX data suggest, even if petrographic and chemical results suggest that different raw materials may have been used. The data provided by these archeometric analyses have made a significant contribution to the study of Middle and Late Bronze Age pottery from the Catania area, by offering insights into the methods, production processes, and high technical level of the prehistoric craftsmen.

This work is part of a wide scientific project finalized to characterize the Sicilian pottery productions from Greek to Roman Age. In this prospective, local reference groups have been analysed in order to create a database of the circulation and production centres in Sicily during this period. In this framework, a set of 28 waste pottery fragments (III-II century B.C.) from a pit found during excavations at the fortification of Adrano (Sicily) have been studied. Characterization of the samples has been obtained by macroscopic, petrographic (OM), mineralogical (XRD) and chemical (XRF) analyses. Macroscopic analysis of the studied potteries has allowed to distinguish four groups on the basis of grain size, porosity and clay paste color. Petrographic and mineralogical analysis, carried out on a selection of representative samples have allowed us to obtain useful information on the production technology of the studied samples. Moreover, information about raw materials and provenance of clay sediments has been obtained by comparing chemical data of the analysed samples with locally outcropping clay sediments reference data. Finally, chemical results on Adrano potteries have been compared with kiln wastes from Siracusa and Gela. The aim of the present work is to obtain fabric characterizations and technological information on a local reference group of ceramic specimens manufactured in Adrano (Sicily). Petrographic and mineralogical results allow us to esteem high firing temperature suggesting a good technological level of local production; in addition, chemical data suggest a local provenance of raw materials used in the production of the studied samples. The comparison with local production from Siracusa and Gela highlights several differences in the use of raw material and in the technological levels achieved in the different sites, over time. Therefore, this work provides a valuable contribution in defining the local scenario of ceramic production in South-Eastern Sicily during the Hellenistic Age and in producing local reference groups in the petro-archaeometric studies of archaeological potteries.

Understanding the behaviour of building stones when they are subjected to weathering processes represents an important research field related to the conservation and restoration of Cultural Heritage. Salt growth is a significant cause of damage for natural stones. In addition to the properties of the salt and the climatic conditions, the effects of salt weathering are strongly related to the structural and textural features of materials. Therefore, detailed knowledge of the internal structure of building stones is fundamental in order to estimate durability and prevent degradation processes. In this work we show the potential of X-ray micro-tomography in understanding the mechanism by which salts can damage building materials. In detail, we focus on weathering effects due to sodium sulphate on a calcarenite from Sabucina (Sicily) widely used as local building and replacement stone. Overall, the obtained results allow for visualisation and quantification of the changes in the porous structure caused by salt crystallization, supporting the comprehension on how the pore network is modified in coarse-grained stone materials. In particular, salt weathering induces fractures in Sabucina stone, leading to an increase of the total porosity. The resulting pores are characterized by a higher maximum opening and equivalent diameter compared to the pores of a freshly quarried stone.

The microscopic description of ancient pottery is widely used for the fabric definition, classification and provenance assessment. In most cases, however, the description is qualitative. An improvement of the study of archaeological pottery needs a more objective approach with quantitative analysis. In classical scientific literature, the structural features and mineralogical composition of pottery are carried out on thin sections by means of transmitted polarized light microscope. The determination were obtained through observations with and without cross polarizator (nicols). The quantitative measurements are normally achieved with tedious and time consuming table with point counter. In this article the attention has been focused on the automatic identification of structural and textural components of the potteries through optical microscopy. Image analysis techniques have been then used to automatically classify the image components. Results confirm the effectiveness of the proposed approach: petrographic data collection becomes faster with respect to the traditional method providing also quantitative information useful for fabric recognition.

The complete knowledge of the porous structure of rocks is necessarily requested for the prediction of the damages induced by salt crystallization. Nevertheless, the geometric description of the porous structure is usually very difficult because of the variability of the size distribution of voids, ranging from nanometers to millimeters, which generally is not accessible by a single methodology. For this reason, a multi-technique approach was used here: the investigation at sub-micrometric dimensional scale (> 0.004 µm) was carried out by Hg intrusion porosimetry (MIP), whereas the study at the nanoscale required Small Angle Neutron Scattering (SANS) analysis. All the results were interpreted in the framework of a fractal model. The analyses were performed on limestones of different geological formations, cropping out in south-eastern Sicily and largely used as building stones in Baroque monuments of the Noto Valley (belonging to the UNESCO Heritage List).

Mesozoic mudrocks and sandstones from the Longobucco Group (Sila Unit, North Calabria) were mineralogically, chemically, and petrographically analyzed for their burial, diagenesis, and sourcearea weathering histories. These sediments mark an important phase of the regional geological evolution along internal domains of the circum-Mediterranean chains from the Gibraltar Arc (Spain and Morocco) to the Calabria-Peloritani orogen (Italy). The effects of diagenesis on quartzose sandstone-mudstone lithotypes in the Mesozoic Longobucco Group succession are quantified.The basal Longobucco Group consists of continental clastic redbeds deposited in a rapidly subsiding rift-valley basin, overlain by shallow-marine to deep-marine carbonate and clastic strata. These sediments were analyzed using thin-section petrography, SEM/EDS, X-ray diffraction (XRD), and fluorescence.Quartzarenites display heterogeneous distributions of authigenic quartz, kaolin, illite, feldspar, and minor carbonate cementation. Authigenic zoned syntaxial overgrowths on detrital quartz represent the principal cement, and interstitial clay is an important component of these lithotypes.The mineralogical assemblage of mudrocks is dominated by illite and illite/smectite mixed layers. This observation, coupled with the CIA index and the A-CN-K plot, suggests post-depositional K-enrichment. Paleoweathering indices (CIW and PIA ratios) suggest that the source experienced intense weathering and that mudrocks likely record recycling from metasedimentary basement rocks.Clay-mineral distributions of sandstone/mudstone lithotypes indicate that mixed-layer illite/smectite with ordered interstratification (from R = 1 to R = 3) dominates mudstone mineralogy. Authigenic clays in sandstone are kaolinite, illite, chlorite, and kaolinite illitization as pore filling and lining. These authigenic clays show a distinct distribution, reflecting differences in burial/temperature history. The illite crystallinity index, the illitization of kaolinite, and the occurrence of high-illite I/S mixed-layer clay minerals suggest burial depths of at least 4-6 km and a temperature typical of the boundary between late diagenesis to low anchizone.

Laboratory measurement of density values of representative crystalline rocks of the Peloritani Mountains, southern Italy, constrain the interpretation of gravity data collected along a profile from the Tyrrhenian Sea to the Mt. Etna volcano. These data contribute detail to crustal models of this section of the southern Italy orogenic system. Regional gravity modeling, constrained by new petrophysical data, yields the following conclusions: (1) existence of a southward-transported nappe belt of a more internal domain; (2) interpretation of the Taormina tectonic line as the morphological evidence of the thrusting of the Kabilo-Calabrian terrane over the Apenninian-Maghrebian units; (3) reconstruction of the Moho geometry along the geotransect, confirming the abrupt change in depth just starting from the Tyrrhenian coastal zone of Sicily.

Petrographic, geochemical and geochronological work on a metavolcanic suite interbedded in a metapelitic sequence of the Palaeozoic basement in the Peloritan Mountains (Sicily) is used to contribute to a better understanding of the pre-Variscan geodynamic evolution of the former Alboran microplate. Major and trace element data show that the volcanic suite consists of two main groups: an Intermediate Unit of andesites and dacites with volcanic arc affinity and a Felsic Porphyroid Unit of rhyolites with peraluminous composition. Isotope dilution thermal ionization mass spectrometry U-Pb analyses for single- and multigrain zircon fractions from four samples of the felsic porphyroids yield results that are tightly clustered on or near concordia giving Caradoc ages in the range of 456-452 Ma. The consistent morphological characteristics and oscillatory zoning of the zircons indicate single-stage magmatic crystallization. Xenocrystic zircon grains with ages of 1150 and 2015 Ma indicate that these rocks were developed upon a cratonic basement with Grenvillian and Transamazonian components, hence supporting a peri-Gondwanan origin. From the combined evidence we conclude that this portion of the Alboran microplate formed as a Mid-Ordovician volcanic arc in a sector of the peri-Gondwanan terranes that was affected by a tectonothermal Caradoc event. [ABSTRACT FROM AUTHOR]

Abstract During the final stages of the emplacement of the Hercynian batholith, a calc-alkaline dyke swarm intersected the crystalline basement of Sardinia. In mid-eastern Sardinia, these dykes range in composition from basaltic andesite to dacites-rhyolites with oligophyric and porphyritic textures, respectively. Plagioclase is the dominant phase among the phenocrysts, with subordinate brown and green amphibole; biotite, K-feldspar and quartz are abundant in more differentiated compositions. The biotite Rb-Sr age of this magmatism ranges between 291 and 271 Ma. Compositional data can be modelled using two separate trends: 1) AFC-type processes with fractionation of An-rich plagioclase, orthopyroxene and Cr-rich clinopyroxene are responsible for compositional variations amongst the most basic rocks; 2) andesitic to rhyolitic magmas evolve starting from basic magmas which are aligned along the first trend due to hybridization process. The complex and long-lived mafic magma and the crust interaction indicate a MASH-like scenario characterized by different magma chambers, as proposed for the late-Hercynian magmatism in other areas.

The recent discovery of the Sphinx Room, belonging to the Domus AureaEsquiline wing, thanks to the framework given by the project “Non-destructive analytical studies at Parco Archeologico del Colosseo (Rome, Italy)”, allowed to perform an analytical campaign, both in situ and on micro-fragments. The first aim was to contribute to the overall comprehension of the Domus Aureacomplex and to contextualize the newly-discovered room inside this extraordinary imperial architecture by means of an archaeometrical characterisation of the painting materials. The palette, composed of Egyptian blue, green earths, iron- and lead-based red, orange and yellow, calcite, carbon-based black, allowed to compare the Sphinx Room to Corridor 92 and Room 114 of Domus Aureaand to other sites in Rome. Furthermore, the employ of an organic binder in some spots can be put forward based on spectroscopic results, which does not exclude a wider use of the a fresco. Furthermore, a complementary methodological strategy was designed, in order to achieve a complete characterization of the materials. In addition to the well-known combination of portable X-ray fluorescence and portable/laboratory Raman analyses, Infrared Fourier Transform Spectroscopy was used, both in situ (Diffuse Reflectance) and in the lab (Attenuated Total Reflectance). The results confirm the suitability of this approach for the characterization of Roman wall paintings, where both inorganic and organic materials are simultaneously present.