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EN
Chlorite-mica-quartz schist in the Gierczyn-Przecznica area in SW Poland contains polymetallic ores which were the source of tin and cobalt in the past. This mineralogical study revealed the presence of silver-bearing minerals including members of the tetrahedrite (Ag <3 apfu) and freibergite series (3 < Ag < 8 apfu), galena (0.26–1.48 wt.% Ag), and a phase with the chemical composition of Te-rich canfieldite Ag8Sn(S,Te)6. In Przecznica Sn-sulphides are represented by stannite while cobaltite is the most abundant host for cobalt, followed by Co-bearing arsenopyrite. Glaucodot, ullmannite and members of the löllingite-rammelsbergite solid-solution series (Fe,Ni,Co)As2 also contain cobalt but are scarce in the samples. An exposure in the “Psi Grzbiet” area is characterized by the presence of Ag, Ni, Sb and Te minerals accompanied by very small amounts of As-bearing phases (represented by arsenopyrite) while the mineralogical composition in the Przecznica area is characterized by an abundance of As phases and a lack of Sb minerals. Sulphur isotopes of sulphides from Przecznica are heavier than in most deposits related to the Karkonosze Granite intrusion, while their Pb isotope signature in galena suggests an Early Paleozoic pre-Variscan affinity rather than a Variscan one.
EN
We reconstruct palaeoenvironmental changes since the Late Holocene in the Orava-Nowy Targ Basin, with an emphasis on anthropogenic influence (Walker et al., 2018). This reconstruction employs multiproxy analyses of the Otrębowskie Brzegi poor fen. We combined radiocarbon and 210Pb dating with elemental geochemistry, stable lead isotopes, and palaeobotanical analyses. The core we investigated covers a period from 4200 ± 100 BC to the present, with a peat accumulation rate varying between 0.001 and 0.243 cm y-1. Heavy metal concentrations, Pb isotopic ratios, and a palynological analysis revealed a significant impact of human activities in the past. The highest concentration and accumulation rate of Pb, were found around 1950 AD. The 206Pb/207Pb quotient ranged between 1.168 and 1.223, with average value around 1.198. Most of the interpretation was based on Pb and its stable isotopes; however, other elements were also important indicators of natural and anthropogenic environmental changes. Our results revealed similarities between the geochemical composition of the peatland studied and other peatlands from the Orava-Nowy Targ Basin.
EN
We describe a methodology of investigation of both Cu metal matrix and its mineral inclusions that aims at increasing the effectiveness of identifying the type of ore used in metal production. We point to sulphosalt ores as the main source of metal for the Final Neolithic/Early Bronze Age copper artefacts from southern Poland. The inclusions, rich in Ag, As, Sb and Sn, document the type of ore, regardless of the metallurgical process leading to depletion of As and Sb. The copper metal should contain neither Sb nor As, hence both of these elements, if originally present in ore, can be preserved only in inclusions. The concentrations of Ag, Sb, As and Sn in the artefacts investigated, the presence of inclusions, and their chemical composition, are the key indicators for the determination of the mineralogical composition of the original ores. Given the high concentrations of Sb, As and Ag in the Cu metal and mineralogy of the inclusions, the ore must have contained varying proportions of Ag-bearing tetrahedrite (Cu,Fe)12Sb4S13 and tennantite (Cu,Fe)12As4S13. Mineralogical compositions of the copper ores indicate the deposits in Slovakia (Spania Dolina) as the source of metal for the artefacts investigated. The results of Pb and Cu isotopic analyses carried out for this study support those conclusions.
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