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In 2016, a Stollhof-type copper hoard was found during an excavation in Magyaregres, Hungary. It was placed in a cooking pot, and deposited upside down within the boundaries of an Early Copper Age settlement. Similar hoards dating to the end of the 5th millennium BCE are well-known from Central Europe, however, this hoard represents the only one so far with thoroughly documented finding circumstances. The hoard contained 681 pieces of copper, 264 pieces of stone and a single Spondylus bead, along with 19 pieces of small tubular spiral copper coils, three spiral copper bracelets, and two large, spectacle spiral copper pendants. Until now, information on the provenance of raw materials and how such copper artefacts were manufactured has not been available. The artefacts were studied under optical microscopes to reveal the manufacturing process. Trace elemental composition (HR-ICP-MS) and lead isotope ratios (MC-ICP-MS) were measured to explore the provenance of raw materials. The ornaments were rolled or folded and coiled from thin sheets of copper using fahlore copper probably originating from the Northwestern Carpathians. A complex archaeological approach was employed to reveal the provenance, distribution and the social roles the ornaments could have played in the life of a Copper Age community. Evidence for local metallurgy was lacking in contemporaneous Transdanubian sites, therefore it is likely that the items of the hoard were manufactured closer to the raw material source, prior to being transported to Transdanubia as finished products. The method of deposition implies that such items were associated with special social contexts, represented exceptional values, and the context of deposition was also highly prescribed. The Magyaregres hoard serves as the first firm piece of evidence for the existence of a typologically independent Central European metallurgical circle which exploited the raw material sources located within its distribution.

This paper represents the first systematic Pb isotope investigation of Italian Medieval coins and aims to provide new parameters for a general historical interpretation of coin production and circulation in Medieval Europe. We collected more than one hundred specimens, minted in a period between 9th - 14th centuries AD and coming mostly from archaeological sites of Tuscany. Here we report the results on the oldest group of (44) coins, dated between the end of the 9th and 11th centuries. All coins where previously characterized with handheld X-ray fluorescence (pXRF) analysis and lead isotope composition (PbIC) was performed using an MC-ICP-Mass Spectrometer. The Carolingian coins have PbIC compatible with Melle silver district; the few Carolingian coins possibly minted in Italy (Venice and Milan) are also compatible with ore districts such as Melle and Harz Mountains. Coins in the names of Italian rulers (9th-10th century) from Lucca, Pavia and other uncertain mints show PbIC compatible with Melle, Black Forest and the Harz Mountains as well. A quite similar pattern applies to coins in the names of Otto I-III and Conrad II (10th-11th century) from Lucca and Pavia mints, although they show a better overlap with the Harz Mountains. The vast majority of early medieval coins issued by the Italian mints investigated in the present paper show isotope compositions that do not match with silver (lead-copper) mines from the Colline Metallifere district of southern Tuscany, notwithstanding their exploitation in the considered period is suggested by many settlements located near mining sites.

Medieval pavements composed of lead-glazed tiles decorated with a variety of techniques continue to inspire questions about the organisation of glaze manufacture, and the supply and origin of lead materials. The tiles analysed in this study are from Suscinio I (a 13th-century pavement) and Suscinio II (a 14th-century pavement), at the Château of Suscinio in Brittany, and also from the 14th-century pavement at the fortified manor house in Brain-sur-Allonnes, Anjou. Lead isotope analysis (LIA) was used to examine samples from 44 lead-glazed tiles, 29 of which are transparent, while 15 are tin-opacified (an exogenous technique in these regions during this period). Five out of the six LIA groups thus identified favour site-specific supply networks, while results for the remaining group, LIA5, indicate a multi-site supply network. After combining LIA results with archaeological and historical data, the most likely provenance for the lead materials in LIA5 is Derbyshire, in the British Isles. Both the importation of ready-to-use glazing mixtures and the use of lead from neighbouring mines can now therefore be discounted as plausible hypotheses for the production of the tin-opacified lead-glazed tiles analysed in this study.

Dating structurally complex fault rocks often results in internally inconsistent ages, as several mineral generations are intergrown at scales << 10 µm and almost always altered to various degrees. We describe here 39Ar-40Ar stepheating using the combination of two independent indicators that allow the discrimination of coexisting mica generations from each other and from the ubiquitous retrogression/alteration phases. A necessary first step is electron probe microanalysis to assess both inventory and spatial distribution of the mineral phases that need to be distinguished a posteriori by 39Ar-40Ar systematics. One indicator is based on mica stoichiometry, which can be proxied by the 39Ar concentration in combination with the 37Ar/39Ar and 38Ar/39Ar (i.e. Ca/K and Cl/K) ratios. The other indicator is the furnace temperature, at which a degassing peak accompanying dehydration and structural collapse is observed. As dehydration rates depend on the average bond strength in the crystal structure, it is predicted (and indeed observed) that the temperature of the differential Ar release peak is variable among different minerals. As the Ca/Cl/K signatures of pure micas coincide with the Ar release peak, their combination identifies the isochemical steps that correspond to the degassing of pristine micas. Only these should be used to date the activity of shear zones. This procedure should become routine in analysing polydeformed metamorphic rocks.

The Etruscan site of Populonia-Baratti (Southern Tuscany, Italy) became in the first millennium BCE one of the most important iron metalworking sites in the Mediterranean region thanks to the exploitation of nearby Elba Island iron ores. Recent studies, however, have demonstrated that, before iron, copper was smelted therein (9th–8th century BCE). The ancient Hellenistic text De mirabilibus auscultationibus by Pseudo-Aristotle states that the ancient inhabitants of Elba Island firstly exploited copper and that, later in, iron was won from the same mines by the inhabitants of Populonia. However, copper occurrences are extremely scanty on the island, while mainland southern Tuscany hosts a number of copper-rich deposits which could have been profitably exploited since Eneolithic. In order to investigate if, and to what extent, copper mining and smelting/working was practiced in this area in Final Bronze Age (FBA) to Early Iron Age (EIA), we have thus compared the lead isotope composition of copper slags found in the Populonia-Baratti area and dated to the 9th–8th century BCE with those of copper-rich ore deposits of southern Tuscany and Elba Island. In addition, few copper-based items from to FBA-EIA hoards of Elba Island have been investigated as well. All copper slag from Baratti-Populonia have lead isotope composition fully comprised within the nearby Campiglia Marittima district, but the ophiolitic copper (either form Tuscan mainland or the neighboring island of Elba) was never worked in this site. Differently, all items from the island of Elba do not show clear genetic relationship neither with Elban nor with the Tuscan mainland copper ores but display a “foreign” Pb signature, suggesting that, even before iron exploitation started, the island of Elba - one of the main crossroads of the Mediterranean Sea - was probably involved in metal trading (rather than metal working) with other regions.

We present a new interpretation of the Bashgumbaz Complex (BSC), a fragment of a large mafic-ultramafic nappe exposed along the Alichur Valley in the Pamir, whose significance is of paramount importance for the understanding of the Cimmerian orogeny in South Pamir. The BSC is exposed along the contact between the SE and SW Pamir and consists of a low-grade metamorphic association dominated by gabbros and serpentinized harzburgites with minor bodies of quartzdiorite and plagiogranite tectonically coupled to basaltic and rhyolitic volcanic products. Tectonic slices of metasedimentary rocks are interleaved within the complex. The BSC is in contact with a sedimentary unit rich in olistostostromes with exotic blocks containing a Lower Permian fauna showing affinity with Central Pamir. The BSC is intruded by a Lower Cretaceous granitic body with a U-Pb zircon age of 117 Ma, crosscutting the whole complex. Petrographic, mineralogical and geochemical data suggest a supra-subduction-zone affinity for the gabbros and diorites. Significant enrichment in LILE and LREE compared to HREE, coupled with negative anomalies of Nb, Ti, Zr and other HFSE support this interpretation. U-Th-Pb dating of zircon from a diorite provides a lower Norian (ca. 222 Ma) youngest-crystallization-age constraint, suggesting that the BSC formed in a supra-subduction setting on the South Pamir terrane prior to the collision between Central and South Pamir blocks. It was later underthrust and then obducted onto the southern margin of the closing Rushan-Pshart Ocean, which separated these two Gondwanan terranes during the Permian–Triassic. The obduction of the Bashgumbaz ophiolites can be considered as a time constraint for the collision between the South and Central Pamir terranes, which occurred within the framework of the Cimmerian orogeny that shaped the southern margin of Eurasia.

Multichronometric analyses were performed on samples from a transect in the French-Italian Western Alps crossing nappes derived from the Briançonnais terrane and the Piemonte-Liguria Ocean, in an endeavour to date both high-pressure (HP) metamorphism and retrogression history. Twelve samples of white mica were analysed by 39Ar-40Ar stepwise heating, complemented by two samples from the Monte Rosa nappe 100 km to the NE and also attributed to the Briançonnais terrane. One Sm-Nd and three Lu-Hf garnet ages from eclogites were also obtained. White mica ages decrease from c. 300 Ma in the westernmost samples (Zone Houillère), reaching c. 300°C during Alpine metamorphism, to 6·45 atoms per formula unit increases eastward. Across the whole traverse, phengitic mica grown during HP metamorphism defines the D1 foliation. Syn-D2 mica is more Si-poor and associated with nappe stacking, exhumation, and hydrous retrogression under greenschist-facies conditions. Syn-D1 phengite is very often corroded, overgrown by, or intergrown with, syn-D2 muscovite. Most importantly, syn-D2 recrystallization is not limited to S2 schistosity domains; micrometre-scale chemical fingerprinting reveals muscovite pseudomorphs after phengite crystals, which could be mistaken for syn-D1 mica based on microstructural arguments alone. The Cl/K ratio in white mica is a useful discriminator, as D2 retrogression was associated with a less saline fluid than eclogitization. As petrology exerts the main control on the isotope record, constraining the petrological and microstructural framework is necessary to correctly interpret the geochronological data, described in both the present study and the literature. Our approach, which ties geochronology to detailed geochemical, petrological and microstructural investigations, identifies 47-48 Ma as the age of HP formation of syn-D1 mica along the studied transect and in the Monte Rosa area. Cretaceous apparent mica ages, which were proposed to date eclogitization by earlier studies based on conventional ‘thermochronology', are due to Ar inheritance in incompletely recrystallized detrital mica grains. The inferred age of the probably locally diachronous, greenschist-facies, low-Si, syn-D2 mica ranges from 39 to 43 Ma. Coexistence of D1 and D2 ages, and the constancy of non-reset D1 ages along the entire transect, provides strong evidence that the D1 white mica ages closely approximate formation ages. Volume diffusion of Ar in white mica (activation energy E = 250 kJ mol−1; pressure-adjusted diffusion coefficient D'0 < 0·03 cm2 s−1) has a subordinate effect on mineral ages compared with both prograde and retrograde recrystallization in most samples

The copper axe blade discovered in the pile dwelling site of Zug-Riedmatt is one of the few Neolithic copper axe blades in Europe that can be dated with certainty. The blade’s form and its metal composition suggest that it is connected both to the south – more specifically to Copper Age cultures in northern Italy and southern Tuscany – and to the copper axe of the famous ice mummy of Tisenjoch (called ‘the Iceman’ or ‘Ötzi’). We were able to confirm this connection to the south by measuring the lead isotope composition of the blade, which traces the blade’s origin to Southern Tuscany. Due to these links to the south, the copper axe blade of Zug-Riedmatt can be described as a key to understanding Neolithic metallurgy north of the Alps in the second half of the fourth millennium BC. As the classification of the blade will have far-reaching consequences in regard to chronology and cultural history, we have decided to make the results of our analyses available as quickly as possible – even if this means that for now we can only discuss some basic results and assumptions about the blade’s context., Archäologische Informationen, Bd. 40 (2017): Archäologische Informationen

The sequence stratigraphic framework and a summary of the fossil fauna of the upper Miocene portion of the Pisco Formation exposed along the western side of the Ica River (southern Peru) is presented through a new geological map encompassing an area of about 200 km2 and detailed chronostratigraphic analyses. Extensive field mapping and sedimentological study of outcrop sections have shown that the Pisco Formation is a cyclical sediment unit composed of at least three fining-upward, unconformity-bounded depositional sequences, designated P0, P1, and P2 from oldest to youngest. In the study area, these sequences progressively onlap a composite basal unconformity from southwest to northeast. Integration of biostratigraphic and tephrochronologic age determinations constrains the ages of the three Pisco sequences within the study area. Based on the age of surrounding sediments, a conservative estimate of the age of P0 suggests deposition of these strata between 17.99 ± 0.10 Ma and 9.00 ± 0.02 Ma, whereas diatom biostratigraphy and calculated 40Ar/39Ar ages converge to indicate that strata of the P1 sequence were deposited sometime between 9.5 Ma and 8.9 Ma and that those of the P2 sequence are younger than 8.5 Ma and older than 6.71 ± 0.02 Ma. Our survey for both vertebrate and macro-invertebrate remains in the three sequences confirms the outstanding paleontological value of the Pisco Formation and contributes to depict regional faunal shifts in the fossil assemblage., Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy), V. 123, N. 2 (2017)

Constraining the timing of the activity of the Main Central Thrust zone (MCTz) and the South Tibetan Detachment System (STDS) is one of the major tasks to understand Himalayan tectonics. These shear zones are crustal scale ductileto-brittle structures running all along the belt. The MCTz and STDS are the lower and upper boundary, respectively, of the Greater Himalayan Sequence (GHS), the metamorphic core of the orogen. In some areas the MCTz is a km-wide shear zone, whereas in other areas it is bounded by two distinct thrusts. In Garhwal (NW India), the structurally lower and upper MCTz boundaries are the Munsiari and Vaikrita Thrusts (Valdiya, 1980), respectively. We constrain the time of activity of the Vaikrita Thrust by 39Ar-40Ar dating of biotite and muscovite from two garnet-bearing mylonitic micaschists and one garnet-staurolite-bearing quartzite. Microstructural observations reveal at least three different mica growth stages with muscovite being larger and more abundant than biotite. Mica-1 highlights a relict foliation, only locally preserved, at high angle with respect to the main mylonitic one; mica-2 grew along the main mylonitic foliation; its small flakes are often shredded; mica-3 forms coronitic structures around garnet porphyroclasts. EPMA on muscovite shows restricted chemical variation, with Ti, Mg and Fe contents being systematically lower in muscovite-3. Biotite from micaschists shows no significant chemical variations, whereas in quartzite biotite-2 shows two distinct compositional clusters. Rocks were crushed and sieved. Biotite and muscovite were separated by gravimetry and extensively handpicked. Biotite step ages range between 8.6 and > 12 Ma, and muscovite step ages between 3.6 and > 7 Ma. As all samples are from the same 10 m wide outcrop, "cooling ages" should be equal. Instead, their large variations are petrogenetically controlled. Since chloritization is pervasive in all samples, we use the Ca/K ratio to identify Ar released from mica sensu stricto from the intergrown alteration phases. Furthermore, the Cl/K ratio (Villa et al., 2014) allows us to distinguish mica-3 from mica-2. Handpicking enriched muscovite-3 over muscovite-2. The results are best explained by mica growth along the main foliation around 9 Ma. Coronites formed c. 3 Ma later during retrograde garnet breakdown, as shown by the lack of internal deformation in micas and by microchemical data. The time span for the activity of the STDS is constrained by a little-deformed pegmatitic dyke close to it. Its white mica grew after the ductile deformation and gave a 39Ar-40Ar age > 16 Ma. Thus, the STDS froze c. 7 Ma earlier compared to the main movement phase of the Vaikrita Thrust

At active volcanoes, petrological studies have been proven to be a reliable approach in defining the depth conditions of magma transport and storage in both the mantle and the crust. Based on fluid inclusion and mineral geothermobarometry in mantle xenoliths, we propose a model for the magma plumbing system of the Island of El Hierro (Canary Islands). The peridotites studied here were entrained in a lava flow exposed in the El Yulan Valley. These lavas are part of the rift volcanism that occurred on El Hierro at approximately 40–30 ka. The peridotites are spinel lherzolites, harzburgites, and dunites which equilibrated in the shallow mantle at pressures between 1.5 and 2 GPa and at temperatures between 800 and 950 °C (low-temperature peridotites; LT), as well as at higher equilibration temperatures of 900 to 1100 °C (high-temperature peridotites; HT). Microthermometry and Raman analyses of fluid inclusions reveal trapping of two distinct fluid phases: early type I metasomatic CO2-N2 fluids (X N2 = 0.01–0.18; fluid density (d) = 1.19 g/cm3), coexisting with silicate-carbonate melts in LT peridotites, and late type II pure CO2 fluids in both LT (d = 1.11–1.00 and 0.75–0.65 g/cm3) and HT (d = 1.04–1.11 and 0.75–0.65 g/cm3) peridotites. While type I fluids represent metasomatic phases in the deep oceanic lithosphere (at depths of 60–65 km) before the onset of magmatic activity, type II CO2 fluids testify to two fluid trapping episodes during the ascent of xenoliths in their host mafic magmas. Identification of magma accumulation zones through interpretation of type II CO2 fluid inclusions and mineral geothermobarometry indicate the presence of a vertically stacked system of interconnected small magma reservoirs in the shallow lithospheric mantle between a depth of 22 and 36 km (or 0.67 to 1 GPa). This magma accumulation region fed a short-lived magma storage region located in the lower oceanic crust at a depth of 10–12 km (or 0.26–0.34 GPa). Following our model, the 40–30-ka-old volcanic activity of El Hierro is related to this mantle-based magma system, a system that we propose fed the recent 2011–2012 eruption.

The Mio – Pliocene Pisco Formation, Peru, is a world renowned Konservat-Lagerstätte. Beside its potential in preserving important information on the history of the Pacific Ocean during the Miocene, the Pisco Fm. provides palaeontologists with the unique opportunity to study in detail the evolution of marine vertebrate fauna during the Neogene. Because diatomites are one of the main lithologies of the Pisco Fm., previous authors have hypothesised exceptionally high sedimentation rates related to the deposition of diatom frustules as the main cause leading to the formation of the Lagerstätte. However, sedimentation rates were never calculated. With the perspective to build a solid stratigraphic framework for the whole Pisco Fm., we started to investigate two important fossiliferous sites: Cerro Colorado and Cerro Los Quesos. Within these two areas, measurement of multiple stratigraphic sections combined with extensive field mapping of a number of distinct marker beds was carried out, which allowed a high-resolution correlation and creation of a local lithostratigraphic framework. Integrated tephrostratigraphy,40Ar/39 Ar dating and diatom biostratigraphy permitted an accurate chronostratigraphy to be established. Both biostratigraphic and radiometric ages converge to indicate a late Miocene age for the two sites, amending previous attribution of Cerro Colorado and Cerro Los Quesos to the middle Miocene. Age models for the site of Cerro Los Quesos reveal that sedimentation rates are high but in line with those of high-productivity environments, thus invalidating the hypothesis of exceptional sedimentation rates as the main cause for the formation of the Lagerstätte. These results are extremely important also in the perspective of building a complete stratigraphic framework for the Pisco Fm.

The task of identifying the provenance of archeological objects is often called "fingerprinting". Amongst the evidence currently used are chemical and isotopic compositions. In contrast to human fingerprints, which according to present forensic knowledge are unique, archeometric fingerprinting is not yet able to identify with certainty the source(s). Exclusion is more decisive than inclusion: according to archeometric arguments an artifact can be certainly incompatible with a number of sources, but can be possibly compatible with a number of others. A judicious combination of several chemical and isotopic indicators can vastly reduce the number of ambiguous assignments and may ultimately lead to a very successful archeological tool.