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La possibilità che il sale avesse avuto un ruolo importante nelle dinamiche insediative del Carso e dell’Istria (Adriatico nord-orientale) fin dalla tarda preistoria è stata ipotizzata principalmente in base a indicatori indiretti, e non è stata validata finora da interventi di campo mirati. Indicatori indiretti quali l’accertato uso pastorale di parecchie grotte carsiche (pastorizia e sale sono legati dalla necessità di integrare l’alimentazione delle greggi di caprovini); la presenza di un numero alto di oggetti “esotici” in molti siti (oggetti dati / ricevuti in cambio di bestiame e sale?); dati etno-storici: presenza di impianti produttivi / saline sicuramente da epoca romana fino al secolo scorso lungo tutto il litorale (in Istria una salina è tuttora attiva). In età protostorica, alcuni materiali ceramici rinvenuti nel sito lungo costa di Stramare di Muggia e nel castelliere di Elleri sarebbero interpretabili come briquetage, e dunque costituirebbero prove dirette della produzione di sale. Nella letteratura specialistica sul sale sono considerati validi sia gli indicatori diretti sia quelli indiretti: nondimeno, la loro tipologia e l’uso esclusivo piuttosto che integrato degli stessi potrebbero costituire tema di discussione teorico-metodologica. L’individuazione di analisi archeometriche (lato sensu) tali da confermare la presenza / produzione di sale in ambienti idonei anche dal punto di vista geo-ambientale è un altro tema di possibile approfondimento, così come quello della dimensione diacronica del fenomeno sale, evidente dall’importanza che hanno in moltissimi casi i dati etno-storici.

Quite rare pottery shards showing a paste rich in black sand particles, possibly igneous minerals, have been discovered in late Republican Roman sites of Trieste area (NE Italy) and SW Slovenia in the Caput Adriae. Most of them belong to late Greco-Italic and Dressel 1 amphora types, in use from the end of the 3rd and the beginning of 1st centuries BC. Following a methodological procedure based on the analysis of igneous temper, proved to be particularly effective by several scholars, numerous minerals have been extracted from the surface of 16 pottery shards, without causing any visible damage to them. Microprobe analysis has allowed the identification of igneous minerals (olivine, clinopyroxene, feldspar and garnet), most likely originating from the Roman or Campanian magmatic provinces. The chemistry of garnets, indicated in the past as a possible tracer of ancient commerce but no longer used in the last decades to study Italian late Republican pottery, has proved to be a promising tool to distinguish among the two magmatic provinces. According to our study, most of the investigated garnets-bearing samples would originate from Somma-Vesuvius while some of them from Latium., Periodico di Mineralogia, Vol. 90 No. 1 (2021)

The Deschmann’s pile-dwellings near Ig (Dežmanova kolišča pri Igu), close to Ljubljana, are probably one of the most famous pile-dwellings of the 3rd millennium BC in the Alpine region: the first excavations were carried out in the 1870s and resumed only c. 90 years later in the same and adjacent areas of the Ljubljana Marshes (Ljubljansko barje). The publication of the materials by J. and P. Korošec in 1969 opened the way to various cultural interpretations, the most recent of which is that by E. Leghissa in 2017: according to her the older phase (28th – 26th century BC), is characterised by pottery of the so-called Ljubljansko barje variant of the Vučedol Culture (redefinition of Phase Ig I after Korošec 1959 and of Late Vučedol period-Vučedol C after Dimitrijević 1979), while the younger one (26th century BC to 25th century BC) has been named Ljubljana Culture (redefinition of Phase Ig II of Korošec 1959 and of Alpine variant of the Ljubljana Culture of Dimitrijević 1979 and of Classical Ljubljana Culture of Govedarica 1989). This study stresses numerous similarities of the Slovenian materials with the pottery of contemporary central European cultures, especially of Somogyvár-Vinkovci and Makó-Kosihy-Čaka cultures, but also with the closer Italian Karst, as indicated already before by other scholars. To check hypotheses based on typological comparisons and try to determine the mechanisms of cultural interactions that connected more or less distant regions, destructive – X-ray diffraction and optical microscopy – and non-destructive analyses – Xray computed microtomography and prompt gamma activation analysis – have been carried out thanks to the collaboration of an interdisciplinary international team. The results obtained so far for the pottery materials attributed to the Ljubljana Culture will be presented at the EAA Conference in Budapest.

We analysed the crystallography and the chemistry (major and trace elements) of 16 Cr-diopsides belonging to mantle xenoliths from northern (Waw-En-Namus, Libya; Bou-Ibalrhatene and Tafraoute, Morocco) and central Africa (Nyos and Barombi maars, Cameroon). These mantle xenoliths were extracted from mantle domains underlying a metacraton (Libya), a pericraton (Morocco), and a Pan-African mobile belt (Cameroon). The clinopyroxenes from pericratonic and mobile belt occurrences show similar geochemical features. They usually have high R3+ content and low Ca. When normalized to chondrite abundances, their incompatible trace elements show a wide spectrum of patterns, from slightly depleted to slightly enriched and U-shaped patterns. Such features may indicate interaction with carbonatitic and silicic melts. Their Vcell suggest different equilibrature pressures that are compatible with an ascending diapir and/or entrapment by magmas at different depths within the lithospheric mantle. It is important to stress that variable cell and tetrahedron volumes suggest that Libyan clinopyroxenes formed at variable depths. Those arising from shallower depth are less depleted and may display enriched and U-shaped patterns, while clinopyroxenes deriving from deeper zones display depleted and flat incompatible element patterns, possibly suggesting a melt extraction preceding the delamination of the SCLM.

The report “Greenstone” shaft-hole axes of NE Italy, Slovenia, Croatia: a new research project presented at the 39th IIPP Scientific Conference dedicated to raw materials and exchanges in Italian prehistory, held in Firenze in 2004, reviewed the situation of the studies on this class of artefacts and presented an agenda for the future. Since then an interdisciplinary team has worked mainly on the following research lines: archaeometric analyses of artefacts – shaft-hole axes and axe blades, for programmatic reasons – found in different sites of Caput Adriae, field surveys, sampling and analyses of geological formations, planned to identify the origin of the different raw materials used to make tools different in typology and, presumably, chronology. This goal has been achieved and the significant increase in data has been used to try to reconstruct the connections and the mechanisms of exchange active from the Neolithic to the beginning of the Bronze Age. The results of the long-term project are synthesized in this paper, which also evaluates their impact on the broader cultural panorama of late prehistory.

A link between magmatism from Large Igneous Provinces (LIPs) and mass extinctions has been observed at leastin five occasions in the Phanerozoic. Volatile species such as S, C and halogen compounds severely impactedthe global environment, released both from melts and thermal metamorphism of volatile-rich sediments. It is stillchallenging to obtain quantitative estimates of the degassed volatiles for ancient magmatic systems, particularly inthe absence of melt inclusions. We propose to fill the gap of knowledge on sulfur partitioning between mineralsand melts, at the aim of using phenocrysts as probes of volatile contents in the melts from which they crystallized.Measuring a volatile concentration in natural minerals (chiefly clinopyroxene) and combining it with an experi-mentally determined partition coefficient (KD), the volatile load in basaltic equilibrium melts can be calculated.We measured a clinopyroxene/melt sulfur KD of 0.0009±0.0001 for basaltic experiments performed at conditionstypical of LIP basalts (FMQ-2; 800-1000 MPa; 1000 ̊-1350 ̊C), through ion microprobe (Nordsim). Basaltic ex-periments were also simultaneously analyzed for Cl and F. For these elements the measured clinopyroxene/meltKDs were more variable, 0.0071±0.0052 and 0.1985±0.087, respectively. Compatibility of sulfur, chlorine andfluorine in clinopyroxene from basaltic systems is markedly different (F>Cl>S), in agreement with what observedby previous studies, and the partition coefficient is well constrained around 0.001 for S. Application of the newlymeasured sulfur KD to samples from thoroughly-dated lava piles from the Deccan Traps and from the SiberianTraps sills reveal that most of the basalts were at or near sulfide saturation (up to ca. 2000 ppm for low fO2melts).

The trigger of the Triassic magmatism in the Eastern Alps (about 235 Ma) is still highly debated, and both extensional and compressional theories are invoked. The first is mainly supported by the related extensional geologic structures, while the second family of theories is supported by the chemistry of the better exposed lithotypes and the high sedimentation rate, typical of a back-arc environment, whose arc is supposed to be located east or south of the Adria Plate. We support a not orogenic genesis for the dolomitic Triassic magmatism due to the presence of coeval magmatic products showing not orogenic features, by the position of such magmatic province during Triassic times (edge of the Intra Pangea Dextral Shear; IPDS) and by the sedimentation rate which appears comparable with that of the North America Atlantic coast located along the IPDS. It is interesting to notice that the IPDS, which probably begun to move in early Permian, started its extensional movement 235 My ago. In this work we mainly attempt to evaluate possible interaction of the magmatic products with the carbonate (host rocks) through the study of the sills located in the Costabella Crest (Moena, TN Italy), and with the comparison with other dolomitic Triassic products, then, to give a small contribute about the geodynamic discussion.Generally, the samples show ipoialine to strong porphyric textures and a variable grade of alteration mainly due to disequilibrium between olivine and the melts in the magmatic chamber. In the Total Alkali Silica diagram the sills fall in the alkaline field (from basanite to tefriphonolite), but this partially contrasts with their paragenesis. Indeed, among the phenocrystals the plagioclase appears very abundant and show a bimodal composition (labradorite and anorthite). Carbonates can be present with primary textures to suggest the presence of small amount of carbonatic melts in the magma chamber possibly explaining the isotopic features found in the dolomitic flows where a strong isotopic Sr variability is associated to small Pb and Nd isotopic ones. Apart the strong interaction with the host rocks and the post-emplacement alterations, three groups with different La/Yb ratio can be recognized suggesting a heterogenic source. Finally, to evaluate the supposed subduction-related chemical features, as the negative Nb anomaly, the Triassic samples have been compared with other not arc related magmatic products placed along the IPDS of the Central Atlantic Magmatic Province emplaced at the TJ boundary. Despite the very different grade of alkalinity, locally their incompatible element pattern shows strong similitudes that we relate to past subductions.

Deccan volcanism in India covered more than 1 million square km and reached a maximum thickness of about 3 km, as presently preserved in the Western Ghats volcanic lava piles. Volcanic activity started at about 66.4 Ma (Jawhar formation) and ended at about 65.5 Ma (Mahabaleshwar unit; Renne et al., 2015). Deccan volcanism straddled the Cretaceous-Paleogene boundary (ca. 66.0 Ma) and possibly contributed to the end-Cretaceous mass extinction event through emission of gases such as SO2, CO2, Cl, F that may have triggered global climate changes. Severe pollution by volcanic gases is supported by the high S and Cl contents (up to 1400 and up to 900 ppm, respectively; Self et al., 2008) measured in a few olivine- and plagioclase-hosted melt inclusions from the Jawhar, Neral, and Thakurvadi Formations (early lava flows, ca. 66.3-66.4 ± 0.1 Ma; Renne et al., 2015) and by magmatic S contents (up to 1800 ppm; Callegaro et al., 2014) calculated from S measurements in clinopyroxenes from the Mahabaleshwar unit (ca. 65.5 ± 0.1; Schoene et al., 2015). Here, we present new analyses of S, Cl, and F, obtained by ion-probe and synchrotron light micro-fluorescence analyses on clinopyroxenes and plagioclase phenocrysts from ?al? lava flow units of the Western Ghats. The volatile contents of the host magmas have been calculated from recently published clinopyroxene/basalt partition coefficients. These new data will describe the time-related variation of volatile elements hosted and eventually emitted by Deccan lavas and shed light on their environmental impact. References: Callegaro S. et al. (2014). Geology 42, 895-898. Renne P.R. et al. (2015). Science 350, 76-78. Schoene B. et al. (2015). Science 347, 192-184. Self S. et al. (2008). Science 319, 1654-1657.

La possibilità che il sale avesse avuto un ruolo importante nelle dinamiche insediative del Carso e dell’Istria (Adriatico nord-orientale) fin dalla tarda preistoria è stata ipotizzata principalmente in base a indicatori indiretti, e non è stata validata finora da interventi di campo mirati. Indicatori indiretti quali l’accertato uso pastorale di parecchie grotte carsiche (pastorizia e sale sono legati dalla necessità di integrare l’alimentazione delle greggi di caprovini); la presenza di un numero alto di oggetti “esotici” in molti siti (oggetti dati / ricevuti in cambio di bestiame e sale?); dati etno-storici: presenza di impianti produttivi / saline sicuramente da epoca romana fino al secolo scorso lungo tutto il litorale (in Istria una salina è tuttora attiva). In età protostorica, alcuni materiali ceramici rinvenuti nel sito lungo costa di Stramare di Muggia e nel castelliere di Elleri sarebbero interpretabili come briquetage, e dunque costituirebbero prove dirette della produzione di sale. Nella letteratura specialistica sul sale sono considerati validi sia gli indicatori diretti sia quelli indiretti: nondimeno, la loro tipologia e l’uso esclusivo piuttosto che integrato degli stessi potrebbero costituire tema di discussione teorico-metodologica. L’individuazione di analisi archeometriche (lato sensu) tali da confermare la presenza / produzione di sale in ambienti idonei anche dal punto di vista geo-ambientale è un altro tema di possibile approfondimento (il team interdisciplinare UniTs-ICTP prevede di affrontare la questione a partire dal 2015). Da ultimo, sarebbe interessante sviluppare la dimensione diacronica del fenomeno sale, evidente dall’importanza che hanno in moltissimi casi i dati etno-storici.

The lithospheric architecture of Africa consists of several Archean cratons and smaller cratonic fragments, stitched together and flanked by younger fold belts. The three larger cratons (West Africa, Congo and Kalahari Cratons) are underlain by Sub Continental Lithospheric Mantle (SCLM) extending to ≥300 km depth and having a prevailing depleted composition. Three series of spinel peridotite xenoliths from Waw-En-Namus (Libya; LB hereafter), Tafraoute and Bou-Ibalrhatene (Morocco; MOR), Barombi Mbo and Lake Nyos (Cameroon; CA) have been investigated to provide a new knowledge of the mantle beneath North-Western Africa continent. In particular MOR and LB should reflect peri- and meta-cratonic conditions, respectively while CA are from the Cameroon volcanic line whose products outcrop within a polycyclic mobile belt. According to their chemistry, the spinels from CAM and MOR xenoliths are magmatic cumulates while LB are representatives of ambient lithospheric peridotites. From a structural point of view, the CAM and MOR spinels are rather similar having comparable cell edges and oxygen positional parameters. The cation distribution allows the determination of an intracrystalline temperature in the range 560-750 °C. Spinels from LB can be divided in two groups with very different oxygen positional parameter and cell edges. The intracrystalline temperature is 680 °C for the second. There is a similarity of Vcell between the CAM, MOR and LBI cpx (< 434 Å3) while those from LBII show Vcell >435 Å3. According to their REE contents, CAM cpx can be divided in 2 groups (depleted and enriched in LREE compared to CPX-DMM), in MOR there are two, both enriched, but with different behavior of the LREE suggesting evolutions starting from a DMM like composition. LB cpx show 4 groups, all of them being more or less depleted. The OH contents are lowest for the LB cpx (100-300 ppm H2O), while the CAM samples are intermediate (200-400 ppm H2O) and the MOR samples show the highest contents (380-610 ppm H2O). Boron is nearly absent apart from two samples (one olivine and one cpx) from CAM. The xenoliths sampled from a probably juvenile lithosphere at the edge of the Cameroon and Morocco lithospheric roots apparently have cumulus-like spinels probably crystallized in situ from percolating melts and thus do not represent a real spinel-peridotites facies; on the contrary peridotite mantle xenoliths from Libya exhibit spinels with features compatible with a slow ascent of a mantle plume. The juvenile behaviors shown by CAM and MOR spinels seem also to be reflected by the cpx-HREE patterns showing typical DMM features. As opposed, for LB ones, where very depleted HREE patterns appear, recent chemical changes seem to have been superimposed to ancient (and/or deeper?) depletion. Funding was provided by the FRA 2013 project of the Trieste University.