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Practically all commercial gold deposits of Uzbekistan are confined to the so-called Beltau-Kuraminsky volcano-plutonic belt which is a kind of "seam" formed as a result of the subduction of Turkestan paleoocean crust under the Kazakhstan-Kyrgyz microcontinent. Flyshoid rock masses of the Besapan suite (Mid-Ordovician - Lower Silurian age) are represented by four members in the geological structure of the Muruntau orefield. The orefield is located in the eastern part of the large Taskazgan anticline complicated by finer folded dislocations; the Myutenbay deposit is confined to one of these. The Myutenbay deposit represents an eastern flank of the Muruntau deposit and it is separated from the Muruntau deposit itself by the zone of the Southern fault. In recent years, micro- and nanomineralogical studies have been carried out on ores from deposits in the Muruntau ore field using a Jeol Superprobe electron-microanalyser and a wide occurrence of tellurides and selenides of Au, Ag, Pb, Sb has been recognized. Tellurides and telluroselenides of bismuth are particularly abundant. A certain vertical zoning is observed in the distribution of tellurides and selenides. Aguilarite (Ag4SeS), naumannite (Ag2Se) and clausthalite (PbSe) are developed at near-surface levels; joseite-B (Bi4Te2S) and pilsenite (Bi4Te3) occur at intermediate levels. Other minerals, such as kawazulite (Bi2Te2Se), aleksite (PbBi2Te2S2), empressite (AgTe), nevskite (Bi(Se,S)) and maldonite (Au2Bi) are also abundant in the Myutenbay deposit. The distribution of the minerals is revealed to have a zoned pattern. The Myutenbay deposit is considered to be the least eroded, deepest block of the giant gold system of "Greater Muruntau".
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