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The general features of several important mineral deposits of polymetallic character in the Republic of Northern Macedonia that have been actively exploited in the past are described. These include the Buchim copper mine and Sasa, Zletovo and Toranica lead-zinc mines, as well as some ore prospects that have been extensively explored for years. In addition, sites with known ore reserves, but which are not yet at the exploitation stage are presented, including Plavica, Ilovica, Kadiica, Borov Dol and others. The elaborated RIS-RESERVES program is used to affirm numerous parameters related to the definition of ore reserves in the deposits, and has now provided the opportunity for preparation of an overview which shows the major metallogenetic characteristics of the deposits with their techno-economic parameters. This approach enables affirmation of the potential of the polymetallic ore deposits in the Republic of Northern Macedonia.

The Altaids is one of the largest accretionary orogenic collages in the world with the highest rate of Phanerozoic continental growth and significant metallogenic importance. It is widely accepted that subduction-related orogenesis of the Altaids started in the late Precambrian and gradually migrated southward (present coordinates). However, it is uncertain when and how the building of the Altaids was finally completed. Based on structural geology, geochemical, geochronological, and paleomagnetic data, this paper presents late Paleozoic to early Mesozoic accretionary tectonics of two key areas, North Xinjiang in the west and Inner Mongolia in the east, together with neighboring Mongolia. The late Paleozoic tectonics of North Xinjiang and adjacent areas were characterized by continuous southward accretion along the wide southern active margin of Siberia and its final amalgamation with the passive margin of Tarim, which may have lasted to the end-Permian to early/mid-Triassic. In contrast, in Inner Mongolia and adjacent areas two wide accretionary wedges developed along the southern active margin of Siberia and the northern active margin of the North China craton, which may have lasted to the mid-Triassic. The final products of the long-lived accretionary processes in the southern Altaids include late Paleozoic to Permian arcs, late Paleozoic to mid-Triassic accretionary wedges composed of radiolarian cherts, pillow lavas, and ophiolitic fragments, and high-pressure/ultrahigh-pressure metamorphic rocks. Permian Alaskan-type zoned mafic-ultramafic complexes intruded along some major faults of the Tien Shan. We define a new Tarim suture zone immediately north of the Tarim craton that is probably now buried below the Tien Shan as a result of northward subduction of the Tarim block in the Cenozoic. The docking of the Tarim and North China cratons against the southern active margin of Siberia in the end-Permian to mid-Triassic resulted in the final closure of the Paleoasian Ocean and terminated the accretionary orogenesis of the southern Altaids in this part of Central Asia. This complex geodynamic evolution led to formation of giant metal deposits in Central Asia and to substantial continental growth.

The Daye district represents one of the largest concentrations of skarn deposits in eastern China. There are two major types of skarn deposits (Fe skarn vs. Cu skarn) within this district, both genetically related to late Mesozoic high-K calc-alkaline granitoids. In this study, we present in situ compositional and Sr–Nd isotopic investigations of apatite from granitoids associated with Fe skarn and Cu skarn deposits to put constraints on the magma source, evolution, and volatile composition, which provide significant new insights into the genesis of the two contrasting mineralization styles in the Daye district. Apatite from granitoids related to Cu skarns and Lingxiang Fe skarn has ε Nd ( t ) values of − 8 to − 4, similar to that of the contemporaneous mafic rocks in the Daye district, which were dominantly derived from an enriched lithospheric mantle source. Apatite in granitoids associated with the Chengchao Fe skarn has lower ε Nd ( t ) values of − 15 to − 9, suggesting larger degrees of contaminations from ancient lower crust materials. Fractionation models based on apatite Sr/Y and Eu/Eu* ratios, suggest that magmas related with the Cu skarns have experienced amphibole-dominated fractionation under high pressure and hydrous conditions, whereas those associated with Fe skarns have undergone plagioclase-dominated fractionation at relatively low pressure and dry conditions. Based on results of apatite compositional analysis and apatite-melt partitioning data, the estimated magma Cl contents for the Fe skarn range from 3260 to 13,940 ppm, significantly higher than those for the Cu skarn (Cl = 430–5990 ppm). Apatite from Fe skarn-related intrusions has ( 87 Sr/ 86 Sr) t ranging from 0.7073 to 0.7082, whereas the variety from Cu skarn-related intrusions displays lower ( 87 Sr/ 86 Sr) t of 0.7054–0.7061. These Sr isotope data, combined with whole-rock S isotopes of this study and previous investigations suggest that the Fe skarn-related intrusions have assimilated larger amount of evaporite-bearing carbonate during magma ascent and emplacement. The assimilation process may have not only promoted magmatic water exsolution but also provided sufficient amount of Cl − and SO 4 2 - , which facilitated effective complexation and transportation of Fe 2+ and subsequent oxidization of ferrous Fe to precipitate magnetite, respectively. We suggest that evaporite assimilation into the granitoid magmas has played a crucial role in the large-scaled Fe skarn mineralization in the Daye district. This study highlights that apatite is a sensitive petrogenetic-metallogenic indicator for granitoids and thus can be useful in mineral exploration.

Abstract Metallogeny is the science of ore and mineral deposit formation in geological space and time. Metallogeny is interdisciplinary by nature, comprising elements of natural science disciplines such as planetology to solid state physics and chemistry, and volcanology. It is the experimental forefront of research and bold thinking, based on an ever-growing foundation of solid knowledge. Therefore, metallogeny is not a closed system of knowledge but a fast-growing assemblage of structured and unstructured information in perpetual flux. This paper intends to review its current state and trends. The latter may introduce speculation and fuzziness. Metallogeny has existed for over 100 years as a branch of Earth Science. From the discovery of plate tectonics (ca. 1950) to the end of the last century, metallogeny passed through a worldwide phase of formally published ‘metallogenetic’ maps. In the last decades, a rapidly growing number of scientists, digitization and splendid new tools fundamentally boosted research. More innovations may be expected by the growing use of an evolving systematic ‘Geodata Science’ for metallogenic research by an increasingly global human talent pool. Future requirements for metallic and mineral raw materials, especially the critical natural elements and compounds that are needed for the nascent carbon-free economy, already drive activities on stock markets and in the resource industry. State geological surveys, academia and private companies embrace the challenges. The new age requires intensified metallogenic backing. In this paper, principles of metallogeny are recalled concerning concepts and terms. A metallogenic classification of ore and mineral deposits is proposed, and the intimate relations of metallogenesis with geodynamics are sketched (ancient lid tectonics and modern plate tectonics). Metallogenic models assemble a great diversity of data that allow an ever better understanding of ore formation, foremost by illuminating the geological source-to-trap migration of ore metals, the petrogenetic and geodynamic–tectonic setting, the spatial architecture of ore deposits and the nature and precise timing of involved processes. Applied metallogeny allows companies to choose strategy and tactics for exploration investment and for planning the work. Based on comprehensive metallogenic knowledge, mineral system analysis (MSA) selects those elements of complex metallogenic models, which are detectable and can guide exploration in order to support applications such as mineral prospectivity mapping, mineral potential evaluation and targeting of detailed investigations. MSA founded on metallogenic models can be applied across whole continents, or at the scale of regional greenfield search, or in brownfields at district to camp scale. By delivering the fundamental keys for MSA, supported by unceasing innovative research, the stream of new metallogenic insights is essential for improving endowment estimates and for successful exploration.

Based on a worldwide database of lamprophyres, N.M.S. Rock (1991) noted that \"... Lamprophyres are a missing element in the traditional 'granites + mineralization' maxim which should no longer be ignored ...\".The Erzgebirge or \"Ore Mountains\" province is a key locality in the European Variscides to observe the important relationships between granites, lamprophyres, and a spectacular array of spatially overlapping mineralization types. Lamprophyre dikes and associated magmatic rocks were systematically mapped in the mining fields of the Erzgebirge and surrounding areas. Data are presented that unarguably demonstrate the important role played by lamprophyric rocks in the Erzgebirge ore province. Three intrusive stages of lamprophyres indicate significant mantle-associated magmatic pulses during the Permo-Carboniferous. Sn-W-Mo, Ag-base metal, and U mineralization events show a close spatial association to post-collisional lamprophyric and small granitic-rhyolitic intrusions which post-date widespread late-collisional granites. The metallogenetic importance of volatile-rich lamprophyres in the Erzgebirge is further affirmed by the overlapping temporal relationship between lamprophyres and post-collisional granitic-rhyolitic intrusions, as determined by modern radiometric dating and age data of lithostratigraphic unites of the Sub-Erzgebirge basin. The model presented in this book is important for exploration for Sn, W, Mo, Ag, Cu, Zn, Pb, In, and U mineralization in the Bohemian massif and comparable ore deposit provinces worldwide.

The newly discovered Nayongzhi Zn-Pb deposit (>20 Mt ores at 1.11-15.65 wt% Zn and 0.59-0.97 wt% Pb) in NW Guizhou province, South China, is hosted by late Ediacaran and early Cambrian carbonate rocks. The ore body is structurally controlled by a kilometer-scale reverse fault-anticline system and occurs as stratiform, lentiform, or steeply dipping vein structures. Its geological feature is comparable to that of the Mississippi Valley-type (MVT) Zn-Pb deposits. δ34S values (+11.8 to +33.0 ppm) of sulfide minerals determined by NanoSIMS have a larger range than those determined by conventional bulk analysis (δ34S = +18.12 to +24.79 ppm). This suggests that S isotopes determined by in situ analysis can reflect the nature of fractionation involved in mineralization. Furthermore, cores of sulfide crystals have higher δ34S values (+26.1 to +33.0 ppm) than their rims (+11.8 to +24.5 ppm). This implies a mixture of multiple S reservoirs or a Rayleigh fractionation of S isotopes occurred during ore formation process. Additionally, both S isotopic compositions determined by in situ and bulk analyses reflect the enrichment of 34S in hydrothermal fluid (δ34Sfluid > +11.8 ppm), a typical characteristic of marine sulfate-derived S. Such S isotopic signatures also show that thermochemical sulfate reduction (TSR) is the dominant mechanism for the incorporation of S2- from SO42-. Pb isotopic ratios of galena obtained by femtosecond LA-MC-ICPMS plot in the field that overlaps with the Pb evolution curve of upper crust contributed to the orogeny and the field of modern lower crust, and can be compared to the Proterozoic metamorphic rocks. The means that the majority of Pb metal is sourced from the basement rocks. Although δ13C values (-4.1 to +0.5 ppm) of calcite separates and corresponding fluids are similar to both fresh limestone (-1.7 to +1.3 ppm) and typical marine carbonate rocks, the δ18O values (+12.4 to +14.1 ppm) are significantly lower than both limestone (+24.1 to +25.5 ppm) and marine carbonate rocks. Such C-O isotopic characteristics suggest that the source of C is ore-hosting carbonate rocks, whereas O has a mixed source of metamorphic fluids and carbonate rocks resulting from water/rock (W/R) interaction. This study demonstrates that (1) fluid mixing caused rapid sulfide precipitation, resulting in significant fractionation of S isotopes; and (2) both the W/R interaction and CO2 degassing controlled local carbonate cyclic process of dissolution → re-crystallization, which provided metastable physical and chemical conditions for giant sulfide mineralization. These two processes are crucial in forming MVT deposits.

The Bor metallogenic zone is one of the most important metallogenic units in the Republic of Serbia. Volcanic processes in this unit are characterized by the domination of extrusive volcanic activity, and the change of depositional environment during the numerous volcanic cycles, as well as facial transitions and huge deposition of syn- and post eruptive resedimented volcanoclastics. The predominant metals in the Bor metallogenic zone are copper and gold, accompanied by iron, base-metals, silver, molybdenum, and minor platinum-group elements. The most prominent morphogenetic types of deposit comprise porphyry copper-gold, cupriferous pyrite, massive base-metal sulphides and hydrothermal veins, iron oxides skarns, carbonate replacement polymetallic deposits, volcanogenic epithermal gold mineralization of the high sulphidation type, and exceptionally rare clasts of copper sulphide ore mechanically accumulated in small sedimentary basins filled by pyroclastics. The total production of the Bor metallogenic zone since 1902 has been near 652 Mt of ore with 4.93 Mt of copper and 280 tons of gold. Mineral resources of the Bor metallogenic zone are estimated at over 20 millions of tons of copper and 1,000 tons of gold. The main geological characteristics of selected metallic mineral deposits in this area are described in this paper.