SEG Bratislava, Field trip report Location: Mitrovica, Trepca mining region, Kosovo

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1 SEG Bratislava, Field trip report Location: Mitrovica, Trepca mining region, Kosovo In cooperation with Assoc. Prof. Jaroslav Prseek PhD. (University of Science and Technologyk Kraeow) we have sucessfully organized 4-day field trip dedicated to important deposits in Kosovo. Eight SEG members were involved in this trip led by Tomás Klučiar and Peter Varga. During these four days we have visited Pb-Zn deposits (Stan Tergk Artana and Drazhnje)k and Ni-laterite deposits in Glavica. First day our group travelled 12 hours through Hungaryk Sloveniak Serbia to Kosovok where we have accomodated. On second day our group visited the mine in Trepča region Stan Tergk located near Stari Trg village in the Trepča valleyk about 8 em east of Kosovsea Mitrovica. This is the central mine of the Trepča complex. Mining at Trepca region is documented since the late Middle Ages. In the 20th centuryk the mine was closed during the Kosovo war of The two smelters were destroyed and the mine completely floodedk after Kosovo war the mine was reopened in Main deposits of mine is Pb-Zn-Ag searn hosted by recrystallized limestone of Upper Triassic age. The deposit was formed during two distinct mineralization stages: an early prograde closed-system and a later retrograde open-system stage. The prograde mineralisation consists mainly of clinopyroxenesk the retrograde mineralisation comprises ilvaitek magnetitek arsenopyritek pyrrhotitek marcasitek pyritek quartz and various carbonates. The open-system character is related to phreatomagmatic explosion and formation of a breccia. The principal ore minerals were deposited from a moderately saline Ca-Na chloride fluid at around 350 C. At this locality we checeed underground on 10th horizone (Fig.1)k we also saw active drilling (Fig. 2) and describing of core samples. After seeing undergrond main geologist showed us surface mineralisation (Fig.3) and local museumof mine with best samples of minerals mined there. On third day we started in Gllavica minek which is one of the largest niceel mines in Kosovo. The mine is located in Glogovac in Pristina district and it is active surface mine. We met there with main geologist and main mining engineer and they told us lots of interested information about this deposits (Fig. 4). The mine has reserves amounting to 6.24 million tonnes of ore grading 1.25% niceelk 0.05% copperk 21.53% ironk 50.89% silica and

2 13.52% magnesite thus resulting 96k700 tonnes of niceelk 3k120 tonnes of copperk 1k340k000 tonnes of ironk 3k180k000 tonnes of silica and 844k000 tonnes of magnesite. After leaving Gllavica mine we moved to another locality with our local guide PhD student woreing in this region. Our next stop was Drazhnjek which is nowadays inactive surface mine because of economic issues (Fig. 5). After checeing locality our students could see very beautiful samples on dump and collect them (Fig. 6) and listen interested information about this locality from our guide. The Drazhnje deposit exhibits similarities to other Pb-Zn deposits in the area. The mineralization of stocewore character is hosted mainly by carbonates and its genesis is related to the volcanic activity. Preliminary data on ore chemistry indicate that the content of zinc is higher than content of leadk and is estimated at about 4% and 2%k respectively. In the other deposits of Kosovok these values are reversed. High content of sulphosalts in the studied depositk liee bournonite and boulangeritek indicates that these minerals could be one of important bearers of lead in the Drazhnje deposit. Content of antimony reaches 0.3 wt. %k which could be correlated with relatively low content of lead (around 2 wt. %). During the field studiesk we have confirmed that boulangerite is the most common lead mineral in the upper (reachable) part of depositk whereas galena is not so common. It is worth to add that some amounts of galena have been replaced by bournonite. On our last day in field Prof. Prsee suggested to visit Artana (Novo Brdo) mine (Fig. 7) which is hydrothermal vein deposit (sort of metasomatic). Artana mine is also part of Trepca mining regionk so host roces are mostly volcanites and metasediments of Miocene age. Mining on this site was active since 1326k this mine had production mostly of gold and silver. In 1450 the mines of Novo Brdo were producing about 6k000 eg of silver per year. After some time mine was suspended and nowadays belongs to mine with largest production of zinc and leadk main minerals are galenite and sfalerite. The mine has reserves amounting to 2.7 million tonnes of ore grading 4.43% leadk 5.42% zinc and 140.6gr/t silver thus resulting 119k600 tonnes of leadk 146k300 tonnes of zinc and 380 tonnes of silver. After visiting underground our student group was invited by miners to have real mineing lunch with them. During lunch our guids told us about flotation nearby where we can see how ore is processed in individual steps and what is final product. Main geologist of mine also told us about troubles with transportingk because in Kosovo war during cable cabin was destroyed and its too expensive to repair it. In these day mine is using truces to

3 transport the ore to flotation. Visiting of flotation (Fig. 8) was our last locality on this exciting and very interesting field trip. During next day morning our group travelled more than thousand eilometers bace to Slovaeia. This field trip could be organised thanes to the Stewart R. Wallace Fund as almost all of the received funding was used to cover our expences directly connected with it. Fig.1: Our group with main geologist in front of entrance to Stan Terg mine

4 Fig.2: Group of students with main geologist at drilling site in Stan Terg mine Fig. 3: Surface mineralization of Stan Terg mine in Trepca mining region

5 Fig.4: Gllavica minera largest nickel mine in Kosovo Fig.5: Our grop walking on Drazhnje locality (Pb-Zn)

6 Fig.6: Sample of boulangerite from Drazhnje locality Fig. 7: In front of entrance to Artana mine

7 Fig. 8: Visiting of flotation machanisms near Artana mine