Mineralogical and geochemical features of the postglacial oxidation zone of the Udokan deposit

Abstract

The frequency of the formation of the oxidation zone of the Udokan copper deposit due to climatic characteristics has been revealed on the basis of the mineralogical analysis of ores compositions. It has been shown that in the zone of the permafrost rocks the copper hydroxosulfates with crystalline hydrate water are formed: hydrobrochantite [Cu15(SO4)4(OH)22 • 5,24-6,6 H2O], hydroanthlerite [Cu2,84-2,94(SO4)(OH)3,44-3,87 • 2,44-3,33H2O], and also there is udokonite [Cu8(SO4)(OH)10 • H2O]. Hydroanthlerite, hydrobrochantite, udokonite comprise up to 50% of copper minerals in oxidized brochantite-anthlerite-malachite ores. Theirs properties allow the use of flotation for the enrichment of all types and varieties of copper ores. The features of chemical elements migration at positive and negative temperatures have been determined according to the results of experimental data on sulfuric acid leaching of oxidized and sulphide ores. It has been determined that under cryogenic conditions the mobility of chemical elements is not only possible, but also for Cu, Ag, Pb, Al, P, Ti and Zr more intensive than at positive temperatures.

Keywords

• криоминералогенез
• минеральные ассоциации
• сернокислотное выщелачивание
• миграция элементов
• кристаллогидраты
• гидроброшантит
• гидроантлерит
• малахит