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At Ustica island (Palermo, Italy), in the area of Casa dei Francesi, 119 fragments of obsidian artifacts were collected on the surface of an agricultural field at an altitude of 50 m asl. In the same area, until now, scientific literature reports only the presence of late Roman pottery (4th–6th centuries AD), and no evidence has appeared that it could be the site of a prehistoric settlement. The most important prehistoric settlement, the Faraglioni Village (Middle Bronze Age) is located 700 m further north, overlooking the sea. Obsidian provenance analyses, performed on the 119 samples with absolutely non-destructive techniques WD-XRF and SEM-EDS, indicate two sources areas: Lipari (93 samples, 78%) and Pantelleria (26 samples, 22%). Concerning the obsidians from the island of Pantelleria, it was possible to also establish the sub-source of Salto la Vecchia. The typological and functional analyses of the 119 obsidian fragments point out that 115 are debitages, some of which show evidence of percussion bulbs, and only 4 are tools with micro-retouching. This work focuses on the geochemical and typological characterization of the obsidian assemblage collected, the characteristics of which suggest the existence of a prehistoric settlement in the area of the Casa dei Francesi or nearby.

In the last twenty years, obsidian artefacts have been found in important and often extensive karst cavities in Southern Italy: three located in Calabria (Grotta della Monaca, and Grotta del Tesauro, in Sant’Agata di Esaro, Cosenza; Grotta Pietra Sant’Angelo in San Lorenzo Bellizzi, Cosenza), one in Puglia (Grotta di Santa Barbara in Polignano a Mare, Bari) and another in Campania (Grotta di Polla, Salerno). All these sites, that have returned a total of 151 obsidian tools, were connected to human frequentation of the underground environments that occurred during the Holocene, which can be precisely located in the vast period between the Neolithic and the Eneolithic (6th–4th millennium BC). They are mainly blades and bladelets, but also burins together with scrapers and cores, generally of small dimensions. SEM-EDS and WD-XRF absolutely non-destructive analyses carried out on these items have shown that all samples have a source area in the obsidian outcrops of the island of Lipari (Messina, Italy). These data confirm that the Aeolian island of Lipari furnished the privileged obsidian extraction outcrops for most of the Neolithic and Eneolithic archaeological sites of Southern Italy.

A new occurrence of the Mn-Ba ore mineral, romanechite, has been discovered in a small paleo-doline of the Apulian karst on Mesozoic carbonate rock successions, characterized by reddish incrustations and nodules made essentially by Fe-bearing calcite. The conditions under which Mn-Ba ore minerals form represent an intriguing area of research, as these minerals can act as scavengers for heavy elements, impacting soils, surface sediments, and even associated aquatic systems. The genesis of romanechite is linked to the progressive interaction of silicate aqueous solutions enriched in Al, Si, and Fe with the limestone substrate. The findings provide new insights into the genetic processes responsible for the formation of reddish Mn incrustations, supporting their polygenetic origin because of the chemical alteration of limestone and allochthonous siliciclastic muds. [ABSTRACT FROM AUTHOR]

The island of Antiparos belongs to the Aegean volcanic arc. The obsidian outcrops here contain pieces of excellent tool-making quality, but of small size making the raw material less attractive. Geological samples collected at Soros beach, at Blaco and Mastichi, in the southern part of the island, were analysed using Optical Microscopy, XRF (whole rock) and SEM-EDS (glass and microliths-microphenocrysts). The results obtained demonstrate the potential for distinguishing the Antiparos obsidian from other major central-western Mediterranean sources in an absolutely non-destructive way, using an XRF spectrometer or alternatively with an SEM equipped with an ED spectrometer.

Beach sands from the Rosa Marina locality (Adriatic coast, southern Italy) were analysed mainly microscopically in order to trace the source areas of their lithoclastic and bioclastic components. The main cropping out sedimentary units were also studied with the objective to identify the potential source areas of lithoclasts. This allowed to establish how the various rock units contribute to the formation of beach sands. The analysis of the bioclastic components allows to estimate the actual role of organisms regarding the supply of this material to the beach. Identification of taxa that are present in the beach sands as shell fragments or other remains was carried out at the genus or family level. Ecological investigation of the same beach and the recognition of sub-environments (mainly distinguished on the basis of the nature of the substrate and of the water depth) was the key topic that allowed to establish the actual source areas of bioclasts in the Rosa Marina beach sands. The sedimentological analysis (including a physical study of the beach and the calculation of some statistical parameters concerning the grain-size curves) shows that the Rosa Marina beach is nowadays subject to erosion.

Porphyroblastic garnet-bearing metagabbros from the base of the lower crust section of the Serre (southern Italy) exhibit multi-stage dehydration and decompression after the Panafrican emplacement of their protoliths. The first dehydration event produced Am-Opx-Cpx-Pl-Grt as the peak assemblage. Two decompression stages are documented by: (1) coronas of Opx-Pl and Opx-Am, and symplectites of Opx-Am-Pl around clinopyroxene within the porphyroblastic garnet as well as in the matrix and (2) symplectites of Pl-Am-Opx-Grt having different textures around the porphyroblastic garnet. During the second decompression stage, a new local, somewhat intense, dehydration occurred and produced rims of Opx + Pl around the porphyroblastic amphibole, or lenses of Pl-Opx-Am-Spl [+ or -] Bt between layers of dominant amphibole. A deformation stage separates older from younger reaction textures. The porphyroblastic garnet, its inclusions and the matrix are affected by fractures, which have been overgrown by coronas and symplectites around the porphyroblastic garnet and the amphibole of the matrix. Preferred P-T estimates are: ~ 900[degrees]C and ~ 1.1 GPa at the metamorphic peak; ~ 850[degrees]C and 0.8-0.9 GPa during the formation of corona around clinopyroxene; 750-650[degrees]C and 0.7-0.8 GPa during the formation of corona around garnet. All these textures formed under granulite-facies conditions. The subsequent metamorphic evolution consists of rehydration under amphibolite-facies conditions. The P-T-t path agrees with the path shown by the uppermost migmatites of the Serre section, and the P-T estimates at the top and the bottom of the section are consistent with the thickness (7-8 km) of the lower crustal segment. A contractional regime, which caused a crustal thickening of about 35 km, was followed by an extensional one producing significant crustal thinning; the change of tectonic regime probably occurred about 300 Ma ago when the emplacement of voluminous granitoids and the initial stages of exhumation of the lower crustal section had taken place. Keywords: metagabbro, lower crust, granulite facies, P-T conditions, Calabria Italy.

The paper presents the metamorphic trajectory recorded by metapelitic migmatites of the upper part of the Hercynian lower continental crust of the Serre (southern Calabria, Italy). The relict minerals, reaction textures and phase equilibria define a clockwise P-T path. The prograde metamorphism from temperature of about 500 [degrees]C and pressure of 4-5 kbar to T< 700 [degrees]C and P ~ 8 kbar stabilized the assemblage Grt + Ky + Bt + Ms(Si/11ox = 3.26-3.29) in the uppermost metapelites of the profile. Progressive heating led to [H.sub.2]O-fluxed and dehydration melting first of Ms, then of Bt at T < 700 [degrees]C in the stability field of sillimanite. This process was followed by nearly isothermal decompression producing additional melt with a transition from Grt to a Grt + Crd stability field. Further decompression caused the formation of Crd-corona around garnet. Nearly isobaric cooling led to rehydration and retrogression across the stability field of andalusite up to the stability field of kyanite. The lowermost metapelites of the studied profile have lost most of the memory of the prograde P-T path; they record decompression and cooling. High-temperature mylonites occur in which boudinage, elongation and pull-aparts characterize the porphyroclasts. The pull-aparts in the high-T mylonites are filled with low-P minerals (Crd + Spl). The Hercynian metamorphic trajectory and the microtextures are consistent with crustal thickening and subsequent extensional regime. During extension, an important tectonic denudation probably caused the isothermal decompression. Extension also occurred in post-Hercynian times as documented by pull-aparts in sillimanite porphyroclasts filled with chloritoid within a low-grade mylonite. Keywords: Hercynian, migmatites, southern Calabria, P-T path.

The occupational risks in silica‐exposed workers have been greatly reduced over the last decades; however, only few studies investigated uncommon forms of exposure to crystalline silica as shown by this case of silicosis in a paint‐production worker. [ABSTRACT FROM AUTHOR]

This present work focuses on the mapping of marbles, decorative patterns and area of the mosaics of the St. Nicola's Basilica in Bari (Italy) by their photogrammetric survey. The extraordinary importance of these mosaics is due to the stylistic uniqueness and the undisputed workmanship and to the employed materials for tesserae. These mosaics include the white and polychrome marbles, used in the Roman age and reused in medieval artistic production, and imitation stones used as substitutes during the past restorations. The digital survey was realised by the photogrammetric reconstruction of mosaics collecting a photo dataset, after the mosaics redrawing by an image processing software and finally implemented it with lithological identification marbles. It allowed to obtain a punctual mapping of materials, through which to identify original areas and restoration areas, decorative patterns, recurring geometries. The research carried out, supported by the photogrammetric reconstruction as established method for high resolution digital reproduction and mapping, not only ensures the conservation and improvement of the enjoyment of the mosaic floors of the St. Nicola's Basilica, but allows to conduct studies on materials, decorative patterns and restoration areas directly on the digitized product. [ABSTRACT FROM AUTHOR]

Aflatoxin B1 (AfB1) is a carcinogenic mycotoxin that contaminates food and feed worldwide. We determined the AfB1-adsorption capability of non-viable Pleurotus eryngii mycelium, an edible fungus, as a potential means for removal of AfB1 from contaminated solutions. Lyophilized mycelium was produced and made enzymatically inert by sterilization at high temperatures. The material thus obtained was characterized by scanning electron microscopy with regard to the morpho-structural properties of the mycotoxin-adsorbing surfaces. The active surfaces appeared rough and sponge-like. The AfB1-mycelium system reached equilibrium at 37°C, 30 min, and pH 5–7, conditions that are compatible with the gastro-intestinal system of animals. The system remained stable for 48 h at room temperature, at pH 3, pH 7, and pH 7.4. A thermodynamic study of the process showed that this is a spontaneous and physical adsorption process, with a maximum of 85 ± 13% of removal efficiency of AfB1 by P. eryngii mycelium. These results suggest that biosorbent materials obtained from the mycelium of the mushroom P. eryngii could be used as a low-cost and effective feed additive for AfB1 detoxification. [ABSTRACT FROM AUTHOR]