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Мінералогічний Журнал Mineralogical Journal (Ukraine)

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Мінералогічний Журнал Mineralogical Journal (Ukraine) МІНЕРАЛОГІЧНИЙ ЖУРНАЛ MINERALOGICAL JOURNAL (UKRAINE) UDC 549.328/.334 (437.6+477) v V. Melnikov, S. Jelen, S. Bondarenko, T. Balintova′ , D. Ozdl′n, A. Grinchenko COMPARATIVE STUDY OF Bi>Te>Se>S MINERALIZATIONS IN SLOVAK REPUBLIC AND TRANSCARPATHIAN REGION OF UKRAINE. PART 1. LOCALITIES, GEOLOGICAL SITUATION AND MINERAL ASSOCIATIONS Comparative analysis of telluride occurrences found in the territory of Slovakia and Transcarpathians (Ukraine) has shown that there is distinct difference between the mode of Au;Ag;Bi;Te;Se mineralization of these regions. But within the area of distribution of neovolcanites Bi;Te;Se;S mineralization is generally represented by similar mineralogical phases. In the Transcarpathian region bismuth tellurides (tsumoite, pilsenite, joseites, native bismuth and poorly studied sulpho;seleno; tellurides of bismuth) were found only in metasomatites as secondary quartzites of the Vyghorlat;Guta ridge area. (Il'kivtsy, Podulky, Smerekiv Kamin'). The similar mineralization have been also found in some neovolcanites of Slovakia (Poruba pod Vigorlatom, Remetska Hamra). E;mail: [email protected] Introduction. Associations of non;ferrous and pre; nium and sulfur can be traced into the structure cious metals occurred due to geochemical diffe; of tellurides (polar isomorphism), it is necessary to rentiation of elements in the upper mantle and describe their composition in the triple system earth crust. There is a certain relation between Te;Se;S. Crystallochemical restriction on replace; "composition" of association of chalcophile ele; ment of tellurium by sulfur does not prevent ments and conditions of their formations [18]. So, accommodation of sulfur in independent positions for example, association of Ag;Au;Hg metals and such as, for example, in the structure of tetra; satellite association of Bi;Te;Se occurs at low tem; dymite and joseite. Therefore among sulfotellu; perature, forming characteristic paragenesises in rides it is possible to expect the discovery of new epithermal polymetallic deposits. Among com; mineral varieties of stoichiometric composition. pounds of chalcophile metals the (Pb, Ag, Au, Cu) Tellurides can be subdivided into three crystal; tellurides and selenides occupy special position lochemical types: 1. Tellurides of transitive metals because of their genetic relation with gold [8, 9, and platinoides. 2. Tellurides of silver, gold and 18]. Owing to the large size the ion of bismuth copper. 3. Tellurides of bismuth, lead, antimony takes special position in the range of three "semi; and mercury. Such subdivision approximately cor; metals" As;Sb;Bi. It is also manifested by distinct responds to transition from high;temperature to affinity of tellurium to bismuth and genetic associ; low;temperature paragenesises. As mineralization ation of bismuth with large atoms such as tellurium processes frequently occur at a wide range of tem; and selenium. At the same time, genetic relation peratures, telluride associations of different crys; between Bi and S is also obvious, which is mani; tallochemical type can often be formed. In addi; fested in formation of a great number of bismuth tion, this wide temperature interval of crystalliza; sulphosalts [18]. Because of strong dispersion of tion observed for some telluride means that they selenium in widespread sulfides it rarely forms se; might be refered as passing;through minerals. Tet; parate minerals. As the significant amount of sele; radymite, tellurobismuthite and tsumoite are present at paragenesises occurring at different © V. Melnikov, S. Jelenv, S. Bondarenko, T. Balintova′, temperature. The composition of tellurides reflects D. Ozdín, A. Grinchenko, 2009 geochemical specificity of the mineralization 38 ISSN 02043548. Mineral. Journ. (Ukraine). 2009. 31, No 4 COMPARATIVE STUDY OF BiTeSeS MINERALIZATIONS IN SLOVAK REPUBLIC environment. They can play the role of some indicators of possible useful (economic) minera; lization that also can be used in practical geology. For epithermal gold among such indicators it can be not only silver and gold tellurides, but also bismuth and lead ones. But for these conditions of mineralization till the present time the layered tellurides of bismuth as minerals of variable composition and the peculiarities of their typo; chemistry have not been studied enough. There are some certain problems in studying the mineralogy of tellurides, especially their classifica; tion and studying some chemical and structural characteristics of their mineral varieties. At present about 75 tellurides have been found but conside; Fig. 1. Small inclusion minerals of tetradymite group rable number of them is not thoroughly studied. It (mostly tetradymite) in zonal bismuthinite (Dúbrava de; is known that the major varieties of tellurides are posit) minerals of the variable composition that form segregations on submicroscopic scale. The use of of Slovakia. Conditionally enough among possible microprobe analysis can solve the problem of analogues of these types of mineralization in the studying their composition, but it is difficult to Transcarpathian region of Ukraine we can men; measure structural parameters of these microseg; tion such occurrences as gold mineralization at regations. At the same time only X;ray analysis can Sauliak [7] and secondary quartzites and confirm authenticity of certain mineral. Without argillizates in neovolcanites of the Vyghorlat;Guta using structural data a number of problematic ridge [21, 22]. Comparative mineralogical investi; phases arises increasingly. Many tellurides are gation carried out on tellurides from Slovakia and related to the rare and insufficiently studied mi; Ukrainian Transcarpathians has shown, that there nerals. Therefore repeated investigation of old are some differences and similarities as well, ma; (museum and field) material with application of nifested in character of Au;Ag;Bi;Te;Se minera; modern method of investigations can lead to new lization occured in these regions. findings. One possible decision for the problems BiTe mineralization of Slovak Republic. mentioned above still remains. It is necessary to Hydrothermal veins with BiTe mineralization in carry out some comparative mineralogical investi; nonvolcanic rocks of Western Carpathians. Te;Se gations in the regions with similar mineragenetic mineralization apart from the neovolcanic rocks histories. occurs in hydrothermal veins of older (mostly This article discusses the results of comparative Carboniferous) tectonic units of the Western analysis of mineralogy of tellurides of Slovakia and Carpathians (Table 1). These units represent Transcarpathian region of Ukraine. The amount of Tatric, Veporic and Gemeric Units that are pre; data available from both sides are not comparable dominantly comprised by granitoid and metamor; because tellurides have been found at more than 20 phic rocks. Bi;Se;Te minerals are often found manifestations within territory of Slovakia and mostly in association with bismuthinite in white only 7 telluride occurrences (but 4 of which are quartz. Specific type is representeed by Bi;Se;(Te) thoroughly studied) have been described till the minerals found at Smolník where predominant Se; present time in the Transcarpathian region of rich phases and selenides forms myrmekite over; Ukraine. Two types of hydrothermal mineraliza; growths. tion of tellurides are distinguished within the terri; Du′brava. The largest stibnite deposit in the tory of Slovakia: 1) hydrothermal veins in Slovak Republic Du′brava is situated in north part (Paleozoic and more older underlying) rocks of of Nízke Tatry Mts. within granitoid rocks non;volcanic origin; 2) hydrothermal veins and (Devonian age) of crystalline basement of Tatric zones of argillization in neovolcanites. The first Unit. The stibnite of Du′brava deposit occurs in type of mineralization was found confined to the veins of milky quartz in which tetradymite have region of Western Carpathians, and the second been described [27]. Tetradymite inclusions were type was described in the central and eastern part found in bismuthinite crystals in quartz in which ISSN 02043548. Мінерал. журн. 2009. 31, № 4 39 v V. MELNIKOV, S. JELEN, S. BONDARENKO et al. Table 1. Tellurides of Slovakia and their localities Locality Forms of occurrences and host rocks Minerals Nonvolcanic rock of Western Carpathians Dúbrava Veins of milky quartz in granitoides Joseite;A, Bi2TeS 2 (S;skippenite), bismuthinite, bismuth Jasenie Veins in migmatites, gneisses Тellurobismuthite, tellurantimony, joseite;B, tsumoite, pilsenite, tetradymite , Hnúšt a Magnesite;talc lenses in mica;schists Bismuthinite, hessite, pilsenite, tsumoite, laitakarite, bismuth, Se;gustavite (PbAgBi3S6) Chyné Hydrothermalites in granite, alter; Baksanite, joséite;A, joséite;B nating sondstones, phylitic schists Katarínska Huta Disseminated impregnation in phy; Tetradymite llites, mica schists, quartzites Kokava nad Rimavicou Quartz veins in gneisses Tellurobismuthite, tetradymite, montanite Krokava Gold;bearing veins in migmatites, Tetradymite (?) gneisses and amphibolites Rochovce Quartz veins in phyllites Bismuthinite, bismuth, ikunolite Gemerská Poloma Magnetite;garnet;pyroxenic skarns Bismuthinite, tetradymite, joseite;B, joseite;A, ingodite, sulfotsumoite, galenobismuthite, gladite Smolník and Úhorná Siderite and quartz;sulphidic veins in Tetradymite, tsumoite (?), ikunolite; laitakarite, phase rocks of greenschist facies (Bi, Sb, Cu)3S4, hedleyite and Se;hedleyite (Bi7Te 2Se) Central Slovakian Neovolcanics
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