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Arsenic contamination poses significant challenges to environmental and public health, with mining activities contributing to its wider distribution. This study investigates the fate of arsenic and iron in mine waters at a decommissioned tin mine, now a visitor mine, located in Ehrenfriedersdorf, Germany, situated in the Free State of Saxony. Despite the general shortage of data, which is common for old mining sites, we explored the complex interplay of climatic conditions, hydrological processes, and arsenic and iron behavior in the mine waters through a comprehensive approach encompassing general site characterization, mine water monitoring, and analysis of local weather data. Over a period of three years, we conducted 14 sampling campaigns, collecting a total of 95 water samples, each consisting of three filtration subsamples, resulting in the analysis of 285 water samples. These samples were collected both aboveground and underground. Aboveground samples included mine outflows, a tailing outflow, and an adjacent creek, while underground sampling points were scattered throughout the mine initially and later focused on the identified "main" mine water system. The chemical data from the analyses were correlated with local climatic water balances to reveal distinctive patterns in arsenic and iron concentrations at various locations within the mine system. Our findings shed light on the hydrological behavior of the mine, helping to elucidate the impact of precipitation and potential evapotranspiration on arsenic and iron concentrations in a tailing outflow, in the flooded mine body, and at the portal of the main dewatering gallery. Our findings emphasize the importance of sustained monitoring and the utilization of local weather data to comprehend metalloid and metal contamination risks in similar mining environments. [ABSTRACT FROM AUTHOR]

This contribution presents new insights into the origin and age relationships of the Geyer tin deposit in the Erzgebirge, Germany. Tin mineralization occurs in skarns, greisen, and in cassiterite-bearing fluorite-quartz veins. Skarn alteration replaces marble layers of the Cambrian Jáchymov Group and occurs in two clearly distinct stages. The first skarn stage forms skarnoid textured assemblages of clinopyroxene, garnet, and wollastonite with no tin phases recognized. Garnet U-Pb ages of this skarn stage (~322 Ma) relate the earlier skarn stage to the emplacement of the Ehrenfriedersdorf granite (~324 to 317 Ma). The second stage of skarn alteration is marked by the occurrence of malayaite and cassiterite associated with garnet recording ages of 307 to 301 Ma. Greisen- and skarn-hosted cassiterite-bearing veins provide U-Pb ages in the range of 308 to 305 Ma, relating greisenization and vein formation to the same magmatic-hydrothermal event as the second skarn stage. This suggests that tin mineralization at Geyer is related to a distinctly younger magmatic-hydrothermal event, clearly postdating the Ehrenfriedersdorf granite, which was previously assumed as the source of the tin-rich fluids. Fluid inclusions show salinities in the range of 1.0 to 31.5 % eq. w(NaCl±CaCl2) and homogenization temperatures between 255 and 340 °C. Cassiterite-associated fluid inclusions show indications for heterogeneous entrapment and dilution of hydrothermal with meteoric fluids. Dilution of high-salinity fluids with low-salinity fluids and cooling of the system was probably a decisive process in the precipitation of cassiterite in the Geyer Sn system. [ABSTRACT FROM AUTHOR]

Using Messbauer spectroscopy on 119Sn impurity atoms, it was demonstrated that in amorphous (GeTe)x(Sb2Te3) films (where x = 0.5, 1, 2, 3) tin atoms replace atoms of tetravalent germanium, which forms a tetrahedral system of chemical bonds with atoms in its local environment. In crystalline films, tin replaces divalent six-coordinated germanium in positions 4b of the NaCl-type crystal lattice. [ABSTRACT FROM AUTHOR]

Using Messbauer spectroscopy on 119Sn impurity atoms, it was demonstrated that in amorphous (GeTe)x(Sb2Te3) films (where x = 0.5, 1, 2, 3) tin atoms replace atoms of tetravalent germanium, which forms a tetrahedral system of chemical bonds with atoms in its local environment. In crystalline films, tin replaces divalent six-coordinated germanium in positions 4b of the NaCl-type crystal lattice. [ABSTRACT FROM AUTHOR]

In this study the metal (liod)s (MLs) contents of Ti, V, Co, As, Mo, Sb, Pb, Al, Cd, Cr, Cu, Hg, Ni, Pb, Sn, Se, Sr, Zn, and Ba, and their non-carcinogenic risks in the samples of green tea and salt in Germany were determined. Zn (3.86 ± 4.62 µg/g) and Mo (0.0005 ± 0.129 µg/g) had the highest and lowest levels in green tea samples. While Zn (2.87 ± 2.49 µg/g) and Ba (not detected) had the highest and lowest levels in salt samples. Also, the estimated daily intake (EDI), target hazard quotient (THQ), and hazard index (HI) values in men was less than women. [ABSTRACT FROM AUTHOR]

Hydroromarchite is a mineral that so far has been found only in a few locations in the world and recognized as a common product of submarine corrosion of pewter artefacts. Here we report a new locality for this rare mineral found at the Saint James Church archaeological site in Creussen, Germany. There it appeared to be a product of weathering of a tin artefact (a tin button) buried in soil of the churchyard for about 300 years. The mineral, found in paragenesis with romarchite and cassiterite, was identified using single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

Skarn-hosted deposits can be important high-grade resources for a variety of metals, but Sn skarns are still of subordinate importance for global mining because of their complex mineralogy and evolution. As part of recent exploration efforts, the economic potential of the Sn–Zn–In mineralization at the Hämmerlein skarn-hosted deposit is currently being re-evaluated. The temporal and spatial evolution of the ore-forming hydrothermal system is still debated. We analyzed fluid inclusion assemblages (FIA) in ore and gangue minerals using conventional and infrared microthermometry and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). We further estimated alteration temperatures with chlorite thermometry and compared the fluid inclusion (FI) record at Hämmerlein with a mineralized greisen sample of the nearby Eibenstock granite. Cassiterite in skarn forms the major mineralization at Hämmerlein during stage I and hosts FIs showing homogenization temperatures of up to 500 °C and salinities between 30 and 47 wt% NaCl eq. Cassiterite from schists and the additional greisen sample from the Eibenstock granite of the later stage II show lower homogenization temperatures (350–400 °C) and considerably lower salinities varying from 1.9 to 6 wt% NaCl eq. Despite the different homogenization temperatures and salinities, the chemical compositions of FIs hosted in both generations of cassiterite show that both (cassiterite in skarn and in schist and greisen) are similar, which points to a common source. The gangue minerals mainly contain low-temperature FIA (max. 330 °C and 2–9 wt% NaCl eq.) and are interpreted to form during further cooling of the system in stage III. Intergrown chlorite has compositions indicating similar temperatures of around 260 °C and is thus also related to stage III. FIA in sphalerite homogenize around 200 °C with salinities between 2 and 6.7 wt% NaCl eq. and show decreasing trace element contents despite having the same salinity range as the gangue minerals, indicating dilution of the ore-fluid during stage IV as a possible precipitation mechanism. Stage I inclusions are solely hosted in cassiterite from skarn, which shows the importance of fluid inclusion analyses in ore minerals, and record remarkable high mineralization temperatures, exceeding the typically temperature range reported in other studies by at least 100 °C. Our results suggest that this main ore stage is related to the early expulsion of a high-salinity brine phase from an underlying magmatic intrusion at depths greater than 3 km, which likely is a relatively short-lived event within the evolution of the hydrothermal system. [ABSTRACT FROM AUTHOR]

Das Tollensetal in Mecklenburg-Vorpommern ist in den letzten Jahren durch die Entdeckung zahlreicher Menschenreste, die z.T. Verletzungen zeigen, und zweier Holzkeulen aus der älteren Nordischen Bronzezeit in den Blickpunkt der Forschung gerückt. Die ungewöhnlichen, ca. 3300-3200 Jahre alten Funde konnten auf einer Länge von ca. 1,5 km entlang des Flusses an verschiedenen Stellen nachgewiesen werden. Mit Unterstützung der DFG haben seit dem Sommer 2010 neben Ausgrabungen auch intensive Tauchprospektionen stattgefunden. Dabei ist es gelungen, eine neue Fundkonzentration (Weltzin 32) in einer Tiefe von bis zu ca. 3 m unter Geländeoberfläche im Fluss zu entdecken. Die bislang aus dem Profil geborgenen zahlreichen Menschenreste liegen nicht mehr in korrektem anatomischen Verband und sind in Flusssande eingebettet. Unter schwierigen Bedingungen ist es gelungen, zwischen den Menschenresten auch weitere Funde in der Fundschicht zu lokalisieren. Der Beitrag stellt die ausgezeichnet erhaltene Lokalität mit ihren wichtigsten Funden vor, unter denen zwei kleine Zinnringe ganz besonders hervorzuheben sind. Die Neufunde werfen wiederum die Frage nach dem Entstehungskontext der Fundschicht im Flusstal auf. Die Autoren favorisieren als Ursache für die ausgedehnte Ablagerung der Überreste von mindestens ca. 110 Individuen, die wiederholt mit Pferdeknochen und Waffen / Pfeilspitzen vergesellschaftet sind, Gewaltkonflikte und möglicherweise auch Opferhandlungen. The discovery of numerous human skeletal remains, with traces of violence in several cases, together with two wooden clubs, dating to period III of the Nordic Bronze has made the Tollense valley in Mecklenburg-Vorpommern the focus of research in the past few years. The unusual finds, c. 3300-3200 years old, were discovered at different locations along a c. 1.5 km long stretch of the river. Supported by the Deutsche Forschungsgemeinschaft (DFG), extensive diving surveys have been conducted in addition to excavations since 2010. During these surveys a new find locality (Weltzin 32) was discovered at a depth of up to 3 m under water level. Lots of human skeletal remains, found scattered and not in anatomical position, could be retrieved from fluviatile sands across a section of the river bank. Despite difficult conditions it was possible to locate further finds among the skeletal material. This article introduces the find locality Weltzin 32 together with its most important finds, among them two small tin spiral rings. These new finds again raise the question of the origin and development of the find layer in the river valley. The authors favour the theory of violent conflicts, possibly also connected to sacrificial rites, as the cause for the accumulation of skeletal remains of at least 110 individuals, which repeatedly occur together with horse bones and weapons (arrowheads). [ABSTRACT FROM AUTHOR]

Today's automakers are under an enormous price and cost pressure arising from both increasing competition and complexity of operations. One way to deal with this challenge is to outsource value creation to the supply network (SN), which then assumes the responsibility for producing variant-specific modules and delivering them just-in-sequence (JIS). This results in tightly coupled buyer–supplier relationships that operate with short reaction times and are characterized by high time dependency and minimal buffers. It increases the risk exposure of buyers to disturbances in their SNs and failures propagate quickly, causing production disruptions. Based on data collected at 14 car-manufacturing plants located in Germany, this research provides an overview and exploratory evidence of current JIS market practice and proposes ways of actively managing the risks inherent in JIS SNs. [ABSTRACT FROM PUBLISHER]

Organotin compounds (OTC) are highly toxic pollutants that have been shown to affect many aquatic ecosystems. Little is known about the input and fate of OTC in terrestrial ecosystems. Here, soil pools, concentrations and fluxes in bulk precipitation, throughfall, fog, litterfall and runoff of OTC and Sntotal were investigated in a forested ecosystem (Picea abies, Karst.) in NE Bavaria, Germany. The concentrations of OTC and Sntotal were generally in the order fog>throughfall>bulk precipitation. Average concentrations of OTCtotal ranged from 57 ng Sn l-1 in fog to 5.8 ng Sn l-1 in bulk precipitation. Concentrations of Sntotal were in the same order but between 490 ng Sn l-1 in fog and 140 ng Sn l-1 in bulk precipitation, on average.Average OTCtotal concentrations in litterfall were 12.9 ng Sn g-1 and those of Sntotal in litterfall 38 ng Sn g-1. All OTC concentrations in runoff were lower than in bulk precipitation, while those of Sntotal were similar to the concentrations in bulk precipitation. Monobutyltin was the dominating OTC in bulk precipitation, throughfall, fog and litterfall, but was seldom detected in the runoff. The annual total deposition of OTCtotal (calculated as throughfall+litterfall) was 172 mg Sn ha-1 year-1, with 45 mg Sn ha-1 year-1 represented by litterfall. The annual runoff from the catchment of OTCtotal amounted to 25 mg Sn ha-1 year-1. The total deposition of Sntotal was 4.9 g Sn ha-1 year-1, of which 0.2 g Sn ha-1 year-1 was litterfall. The annual runoff of Sntotal was 2.4 g Sn ha-1 year-1. The mass balance showed a high retention of OTC and Sntotal in the catchment. The forest soils act as a strong sink for OTC and Sntotal. Only small amounts of deposited OTC are released to runoff. The ratio of soil pools to annual accumulation for total OTC (46 years) indicates that OTC inputs have been occurring already for many decades or have been substantially higher in the past than today. [Copyright &y& Elsevier]

The sources and critical enrichment processes for granite related tin ores are still not well understood. The Erzgebirge represents one of the classical regions for tin mineralization. We investigated the four largest plutons from the Western Erzgebirge (Germany) for the geochemistry of bulk rocks and autocrystic zircons and relate this information to their intrusion ages. The source rocks of the Variscan granites were identified as high-grade metamorphic rocks based on the comparison of Hf-O isotope data on zircons, the abundance of xenocrystic zircon ages as well as Nd and Hf model ages. Among these rocks, restite is the most likely candidate for later Variscan melts. Based on the evolution with time, we could reconstruct enrichment factors for tin and tungsten starting from the protoliths (575 Ma) that were later converted to high-grade metamorphic rocks (340 Ma) and served as sources for the older biotite granites (323–318 Ma) and the tin granites (315–314 Ma). This evolution involved a continuous enrichment of both tin and tungsten with an enrichment factor of ~15 for tin and ~7 for tungsten compared to the upper continental crust (UCC). Ore level concentrations (>10–100 times enrichment) were achieved only in the greisen bodies and dykes by subsequent hydrothermal processes. [ABSTRACT FROM AUTHOR]