This paper describes a newly discovered Bi-Cu±Au mineralization co-occurring with Pb-Zn-Ag hydrothermal mineralization within the Kizhnica-Hajvalia-Badovc ore field, central Kosovo, Vardar Zone. The mineralogy of two styles of Bi-Cu±Au mineralization was described using EPMA in combination with reflected and transmitted light microscopy. Hydrothermal Cu-Bi veinlets in the Kizhnica andesite quarry consist of Bi sulfosalts (bismuthinite, cosalite, aikinite, and krupkaite), pyrite, hematite, chalcopyrite, galena, sphalerite, and tetrahedrite group minerals. Disseminated Bi-Au-Cu-Te mineralization from the contact type of mineralization (hornfels) consists of Bi sulfosalts (cannizzarite, bismuthinite, galenobismutite, cosalite), associated with sulfarsenides (arsenopyrite, gersdorffite, and cobaltite), base metal sulfides (chalcopyrite, pyrite, sphalerite, pyrrhotite, and galena), native gold, native bismuth, and tetradymite. LA-ICP-MS analyses of sphalerite, chalcopyrite, and tetrahedrite indicate increased content of In and Sn in the Kizhnica Bi-Cu-Au mineralizing system, while LA-ICP-MS analyses in pyrites show the presence of many elements, e.g., Au, As, Co, Sb, Tl, Hg, Pb, Bi related to the structure of pyrite or controlled by nano-inclusions. The results suggest a connection between Bi-Cu±Au mineralization and the proximity to intrusive rocks, which may be helpful for Au exploration in Kosovo.

This work presents a mineralogical and geochemical study of Cu-Bi-Ag ± W ores from Janjevo in the Trepça Mineral Belt in Kosovo. This locality indicates a new type of Bi-Cu ± Au mineralization within the Kizhnica-Hajvalia-Badovc ore field, including Cu-Bi ± Ag ± As sulfosalts paragenesis previously not described in Kosovo and in this part of the Vardar Zone. Chemical composition of Bi-Pb ± Cu ±Ag and Cu-Bi ± Ag ± As sulfosalts, sulfides, and associated minerals, as well as their paragenetic relationships and the distribution of minor and trace elements in main ore minerals, are discussed based on microscopy, microprobe, and laser ablation inductively coupled plasma mass spectrometry studies. The Cu-Bi-Ag ± W hydrothermal mineralization in Janjevo was formed during four stages: (1) Early base metal stage, (2) Bismuth stage, (3) Main stage, and (4) Late stage. The Early base metal stage is represented by pyrite, sphalerite I, chalcopyrite I, galena I, bournonite I, tetrahedrite I, siderite, and quartz. The Bismuth stage includes arsenopyrite I, löllingite, native bismuth, galena II, chalcopyrite II, tetrahedrite II, quartz, siderite, and Bi-Pb ± Cu ± Ag sulfosalts: bismuthinite, aikinite, krupkaite, cosalite, and gustavite. The Main stage is represented by chalcopyrite III, tetrahedrite group minerals (tetrahedrite and tennantite) III, galena III, sphalerite II, arsenopyrite II, bournonite II, and siderite. The Cu-Bi ± Ag ± As sulfosalts (pearceite, cupropearceite, wittichenite, and an unknown phase: AgCuBiS 3) associated with galena IV, siderite, and quartz were formed in the final low-temperature Late stage. The application of GGIMFis geothermometry on sphalerite gives the following sphalerite precipitation temperatures: 220-272 °C for sphalerite I and 160-190 °C for sphalerite II. Presented results show that in addition to numerous Bi sulfosalts in Janjevo Cu-Bi-Ag ± W ores, bismuth has been incorporated into base metal sulfides, as well as arsenopyrite. The main carrier of bismuth is arsenopyrite I, which has started the crystallization of the bismuth stage.

The main goal of this paper is to determine the order of the paragenetic sequence and phase transitions of the Ni–Fe sulfide association hosted in listvenites. Listvenites are hydrothermally altered mafic and ultramafic rocks that are often associated with active tectonic settings, such as transform faults, suture zones, and regional extensional faults, usually in contact with volcanic or carbonate rocks. Listvenitization is displayed by a carbonation process when the original olivine, pyroxene, and serpentine group minerals are altered to Mg–Fe–Ca carbonates (magnesite, calcite, dolomite, and siderite), talc, quartz, and accessory Cr spinel, fuchsite, and Ni–Fe sulfides. The formed rocks are highly reactive; therefore, very often, younger hydrothermal processes are observed, overprinting the mineralogy and geochemistry of the original listvenitization products, including accessory Ni–Fe sulfide paragenesis. The studied samples of listvenites were collected from two locations in Kosovo (Vardar Zone): Janjevo and Melenica. The Ni–Fe sulfide textures and relationships with the surrounding listvenite-hosted minerals were obtained using reflected and transmitted light microscopy, while their chemical composition was determined using an electron microprobe. They form accessory mono-or polymetallic aggregates that usually do not exceed 100 μm in size disseminated in the studied listvenites. Generally, the paragenetic sequence of Ni–Fe sulfides is divided into three stages. The first pre-listvenite magmatic phase is represented by pentlandite and millerite. The second listvenite stage consists of Ni–Co bearing pyrite I (Ni content up to 11.57 wt.% [0.24 apfu], and Co content up to 6.54 wt.% [0.14 apfu]) and differentiated thiospinels (violarite + siegenite ± polydymite). The last, late listvenite stage is represented by younger gersdorffite−ullmannite and base metal mineralization: pyrite + marcasite + sphalerite + galena ± chalcopyrite ± sulfosalts. The findings obtained should help in the interpretation of many disseminated accessory Ni–Fe–Co mineralizations associated with mafic and ultramafic rocks worldwide.

Primary ore mineralization in the abandoned Boguszow baryte-polymetallic deposit, located in the Intra-Sudetic Depression, was studied by reflected light mi croscopy and electron microprobe. Ore minerals, occurring as veinlets, irregular aggregates and lenses in baryte veins are hosted by the Upper Carboniferous Che(3)miec rhyodacite laccolith. They are dom inated by galena, sphalerite (with Cd up to 0.04 apfu) and tetrahedrite group minerals (TGM). Four gener ations of the TGM were distinguished according to textural features and Ag content: (1) low-Ag tetrahedrite-(Zn) (Ag: 0.22-0.6 apfu), (2) Ag-enriched tetrahedrite-(Zn) and Ag-enriched tetrahedrite-(Fe) (Ag: 0.71-1.45 apfu), (3) members of the freibergite series: "freibergite-(Fe)" and "freibergite-(Zn)" (Ag: 3.21- 3.48 apfu; Hg: up to 0.75 apfu), (4) member of the "freibergite-(Fe)" series (Ag: 5.32-5.78 apfu). Several elongated inclusions of Ag-bearing sulphosalts within galena crystals were observed (members of the se ries "freibergite-(Fe)" and "freibergite-(Zn)", pyrargyrite and polybasite). These polymetallic sil ver-bearing ores were mined in Boguszow from the 15th to the 19th century. Ad ditionally, small grains of cobalt-enriched lollingite and gersdorffite were observed, which were formed from fluids sourced from the ultramafic basement. The textural characteristics of the ore, the mineral paragenesis and the chemical composition of individual ore minerals indicate low-temperature crystallization conditions.