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Inorganic and organic geochemical data obtained from contact-metasomatic and skarn-like mineralisation and associated country rocks from the Zloty Stok Au-As deposit in Southwest Poland have been studied. Magnetite-rich calcite-dolomite marbles have the highest total organic carbon content of the rocks studied. Organic matter consists of solid bitumen, with a minor extractable fraction composed mainly of low molecular weight aromatics. There are positive correlations between organic matter and Fe 2 O 3 and MgO content, suggesting remobilisation of organic matter by the hydrothermal fluids during serpentinisation processes. Results of the organic geochemical and isotope studies suggest that the hydrocarbons were formed by thermal and later hydrothermal alteration of indigenous organic matter. The ranges of d 34 S values of sulphides show that in Au-rich arsenopyrite and pyrrhotite, most of the sulphur may have originated from a magmatic source. However, some of results indicate a contribution from isotopically heavier sulphur, most probably associated with fluids derived from the metamorphic sedimentary environment. Rare earth element patterns of the mineralised samples point to a granitic source of the studied orebodies.

The Kraków-Lubliniec tectonic zone (KLFZ) in southern Poland, which divides the Małopolska Block (MB) from the Upper Silesia Block (USB), is a portion of the SW margin of the Trans-European Suture Zone. Zircon U-Pb dating of a variety of igneous rocks (granodiorites, dacites, lamprophyre and diabase) from the subsurface Kraków-Lubliniec igneous belt along the KLFZ shows that magmatism spanned within a narrow time period (ca. 10 Ma) between 303.8 ± 2.2 and 292.7 ± 4.9 Ma. The earlier magmatism (303.8 ± 2.2-294.7 ± 2.3 Ma) was felsic calc-alkaline, and the contemporaneous or/and slightly later alkaline volcanism (294.4 ± 4.9-292.7 ± 4.9 Ma) was of mafic-intermediate composition. The felsic rocks (granitoids and dacitoids) are weakly peraluminous, medium to high K, moderate Mg# (0.39-0.46), weakly evolved and I-type rocks. Due to the intensive development of hydrothermal alteration, these rocks are commonly strongly altered and locally mineralized by porphyry and other types of Mo-Cu (W) ores that are closely related to the felsic magmatism in space and time. The zircon U-Pb dating yielded ages which are similar to the previously measured Re-Os ages of molybdenites from the KLFZ. Felsic magmatism at the Myszków Mo-Cu-W deposit yielded ages in the range 301.0 ± 2.1-295.9 ± 2.9 Ma. The youngest rocks dated are from the Mysłów area in the USB-volcanic alkaline rocks (lamprophyre and diabase) of shoshonitic character, with low Mg# (0.49 and 0.69, respectively) and Ni contents (< 62 ppm), indicative of a relatively juvenile magma composition. Inherited zircon cores, remnant detrital zircon from a sediment component in the source rocks, were dated to be ranging from ca. 2775 to 575 Ma. Inheritance of ca. 600 Ma (Cadomian basement) and ca. 1.40 Ga (Mesoproterozoic) is common in the rocks from both blocks, but those from the MB contain additional inheritance with dates of 2.78-2.67 and 2.05-1.92 Ga, both ages characteristic of zircon from the Svecofennian of northern Europe (Baltica). The inherited zircon from the youngest alkaline rocks provided evidence for Mesoproterozoic (ca. 1.55-1.44 and 1.09 Ga) and Palaeoproterozoic (1.96 Ga) thermal events in the USB, and its possible affinity to Avalonian cratonic crust as a source for its igneous protolith. U-Pb isotopic studies of zircons from KL igneous belt indicate its inherited signatures from the crustal sources and magma emplacements during the KLFZ wrenching which allowed channels and room for magma emplacement along the MB and USB in upper Carboniferous-lower Permian on SW margin of the East-European Craton. Mo-Cu (W) ore mineralization, associated with the ~ 300 Ma felsic magmatism, represents rather the product of decompression melting induced in the areas of decreased pressure, undergone in the regional wrench fault zones than the classic Mo-Cu porphyry-style mineralization.

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Streszczenie W artykule szczegółowo scharakteryzowano pod względem mineralogicznym i geochemicznym występowanie telluru i bizmutu w złotonośnych siarczkowych rudach polimctalicznych z zarzu- conych złóż (Złoty Stok, Czarnów, Radzimowicc i Radomicc) oraz punktu mineralizacji (Bardo Śląskie) w Sudetach. Tellur jest zaliczany do pierwiastków krytycznych, a jego rola stale wzrasta. Na rynkach światowych popyt na tellur znacznie przewyższa jego podaż zc względu na coraz większe wykorzystanie np. w produkcji paneli słonecznych czy nośników informacji. Maksymalne kon- centracje telluru około 150 ppm stwierdzono w rudach arscnopirytowo-chalkopirytowych w Ra- dzimowicach, a najwyższe koncentracje bizmutu (ok. 0,5%) w rudach siarczkowych w Czarnowie. W pozostałych obszarach koncentracje Tc są na poziomic od kilku do kilkudziesięciu ppm, a w przy- padku Bi od kilkudziesięciu do kilkuset ppm. Zawartości tc znacznie przewyższają klarki tych metali w skorupie ziemskiej. Wśród zidentyfikowanych minerałów telluru w Radzimowicach i Czarnowie dominują tcllurki Ag (hessyt) oraz w Bardzie Śląskim tcllurki Bi (hcdlcyit i tcllurobismutyt). Tcllurki występują głównie w postaci mikro-wrostków w minerałach siarczkowych w paragcnczic z mi- nerałami Au, Ag i Bi. Minerały bizmutu rozpoznano we wszystkich zbadanych miejscach i re- prezentowane są głównie przez bizmut rodzimy i wtórny minerał bizmutu -bismutynit. Tellur i bizmut wykazują przeważnie silną korelacje (cc>0,6) z Au, Ag i Pb. Krystalizacja głównych minerałów Bi i Tc nastąpiła w zakresie temperatur średnich (300 to 200°C) w dwóch etapach. Pierwszy związany głównie z krystalizacją tcllurków Bi w strefach kontaktowo-mctasomatycznych wokół waryscyjskich intmzji granitoidowych (Czarnów i Bardo Śląskie) i drugi - związany z krystalizacją tcllurków Ag w procesach cpitcrmalnych wokół intruzji porfirowych (Radzimowicc). Bi i Tc odgrywały donośną rolę w procesie wytrącania złota z roztworów hydrotcrmalnych. Pierwiastki tc mają znaczenie mctalogcnicznc i wskaźnikowe przy poszukiwaniach złota.

We applied geochemical (ICP-MS, WD-XRF, GFAAS, and AMA 254) and mineralogical (EPMA) studies of 137 samples to ore mineralization from Middle-Triassic sediment-hosted Zn-Pb (Mississippi Valley-type MVT) and Lower Zechstein sediment-hosted stratiform (SSC) Cu-Ag (Kupferschiefer-type) deposits in Poland. They contain a number of trace elements which are not recovered during the ore processing. Only Cu, Ag, Pb, Ni, Re, Se, Au, and PGE are extracted from Cu-Ag deposits while Zn and Pb are the only elements produced from Zn-Pb deposits. Zn-Pb deposits contain Cd, Ag, Ga, and Ba in slightly elevated concentrations and have potential to be mineral resources. This applies to a lesser extent to other trace elements (Bi, As, Hf, Tl, Sb, Se, and Re). However, only Cd and Ag show high enrichment factors indicative of potential for recovery. The bulk-rock analyses reveal strong correlations between Zn and Cd and Se, As and Mo, and weaker correlations between Ag and Cd, as well as Ga and Zn. Electron microprobe analyses of sphalerite revealed high concentrations of Cd (≤2.6 wt%) and Ag (≤3300 ppm). Zn-Pb deposits have fairly significant estimated resources of Ga and Sc (>1000 tons) and Cd (>10,000 tons). The Cu-Ag deposits have element signatures characterized by high values of Co, V, Ni, and Mo and much lower of Bi, As, Cd, Hg, Mo, Sb, and Tl. Bulk-rock analyses show strong correlations between Se and V; As and Co; Bi and Re; and weaker correlations between, for example, Cu and Mo; V, Ni, Ag and Mo; and Ni, V, and Co and Ni. The EPMA determinations reveal strong enrichments of Ag in Cu sulfides (geerite ≤ 10.1 wt %, chalcocite ≤ 6.28 wt %, bornite ≤ 3.29 wt %, djurleite ≤ 9080 ppm, yarrowite ≤ 6614 ppm, and digenite ≤ 3545 ppm). Silver minerals and alloys, as well as the native Ag and Au, were recorded in the Cu-Ag ores. Large resources of Co, V, and Ni (>100,000 tons) and Sc and Mo (>10,000 tons) are notable in Cu-Ag deposits. A number of trace elements, classified as critical for the economy of the European Union, including Ga and Ba (to a lesser extent Hf, Nb, and Sc) in Zn-Pb deposits, and Co and V in the Cu-Ag deposits, may eventually be recovered in the future from the studied deposits if proper ore-processing circuits and increasing demand are favorable.

As part of the research subject of the Polish Geological Survey, funded by NFOŚiGW, a research project was carried out at PGI-NRI in 2015–2018. Its main task was quantitative and qualitative identification of elements accompanying the main ore and associated elements, including critical ones, and mineralogical identification of their main carriers in metallic ore deposits documented after World War II, representing the main metallogenic formations in Poland. The research focused mainly on drill cores from historical survey boreholes, rarely samples from open-pits and deep mines, representing: Mesozoic Zn-Pb ores, Lower Zechstein Cu-Ag ores, Mesoproterozoic Fe-Ti-V ores, Mo-Cu-W porphyry ores, stratiform Sn ores in the Sudetes, Variscan vein and metasomatic Au-As polymetallic ores, and Cenozoic Ni ores. The PIG-PIB Chemical Laboratory performed analytical work (ICP-MS, WD-XRF, GF-ASS), which allowed quantitative identification of approximately 60 chemical elements. In addition, complementary mineralogical and petrographic studies of the trace element carriers were carried out using a polarizing microscope and an electron microprobe (CAMECA SX-100). Before sampling, metal ore-bearing intervals were examined for the content of chemical elements using a portable spectrometer (Olympus XRF Delta). The results indicate the presence of numerous elements in studied deposits, including those currently regarded as critical for the European Union economy. The collected materials allowed both developing detailed geochemical and mineralogical characteristics of ores from individual deposits and identifying critical elements. They show a clear correlation with the main ore metals, and their resources can be a matter of interest in terms of raw materials.