Low-temperature Ni-As-Sb-S mineralization of the Pb(Ag)-Zn deposits within the Rogozna ore field, Serbo-Macedonian Metallogenic Province: Ore mineralogy, crystal chemistry and paragenetic relationships

Abstract

The Rogozna ore field (ROF) belongs to the Serbo-Macedonian Metallogenic Province (SMMP), and covers a part of the western Dinarides rim and the Vardar ophiolite zone, situated within the Neogene volcanogenic-intrusive complex of calc-alkaline and shoshonitic rocks within the territories of Serbia and Kosovo. It is well-known for its Cu(Au, Pb, Zn) skarn mineralization and Pb(Ag)-Zn hydrothermal deposits and occurences. Mineral associations, deposition order and genesis of the ROF were discussed in detail. Complex ore parageneses were determined in the Crnac, Plakaonica, and Kaludjer Pb(Ag)-Zn deposits and are composed of the following minerals: sulfides (pyrrhotite, chalcopyrrhotite, chalcopyrite, sphalerite, galena, pyrite, marcasite, millerite, bravoite), sulfosalts (arsenopolybasite, tetrahedrite, Ag-bearing tetrahedrite, Zn-bearing tetrahedrite, semseyite, heteromorphite, jamesonite, ferrokesterite), arsenides (nickeline), sulfarsenides and sulfantimonides (gersdorffite, Sb-bearing gersdorffite, Fe-bearing gersdorffite, As-bearing ullmannite, arsenopyrite), native metals (native Au, native Ag), oxides (Cr-spinel, rutile, anatase, leucoxene, magnetite, hematite) and gangue minerals (quartz, silicates, chalcedony, carbonates, monazite(Ce), barite, gypsum, anglesite, cerussite, smithsonite, zaratite, limonite). The high-, medium-, and low-temperature hydrothermal mineral assemblage occur throughout the Pb(Ag)-Zn deposits at Kaludjer-Crnac-Plakaonica ore system, in which the whole ore field as high- to medium-temperature hydrothermal formed at shallow to moderate depth. The following stages of ore mineral formation are recognized in the Pb-Zn mineral assemblage at the ROF: i) pre-ore; ii) high-temperature hydrothermal; iii) hypogene; iv) medium-temperature hydrothermal; v) low-temperature hydrothermal; and vi) supergene. Generally, there are two types of mineralization, brecciated ore veins with ribbon-like textures deposited in amphibolites or in contact with quarz latites, and impregnations within columnar ore bodies hosted in silicified and carbonated serpentinites (listwaenites). Ni-mineralization is represented by significant sulphide, arsenide, sulfarsenide, and sulfantimonide occurrences, but the most significant consists of gersdorffite-ullmannite series (GUS) minerals. It is the most developed in the Kaludjer deposit, much lesser at Plakaonica, whereas in the Crnac deposit it was not noted. The importance of the Ni mineralization is of scientific interest for now, as the attention has been directed only to the exploration of lead and zinc. However, it is believed that plans for the future will be focused on a detailed study of nickel.