Mineralogy and geochemistry of the Hajiabad manganese deposit, Hormozgan province

The Hajiabad manganese deposit is located about 40 km northeast of Hajiabad, Hormozgan Province. This deposit is structurally located in the southeastern border of the Sanandaj-Sirjan zone. The manganese mineralization in the study area is hosted by calcite-dolomitic marbles and mica schists of Devonian age, as layers, veins and massive ores. Based on microscopic investigations, the ores are dominated by manganese occurring as cement of fragments of mica schist rocks and host silicified dolomites by the open space filling process. The major minerals of this deposit include todorokite, spessartine, almandine and calcite and the minor minerals in this deposit are pyrolusite, goethite and quartz. According to geochemical data, the concentration of manganese in the ore bodies are more than 41 wt%. Low levels of P2O5 and TiO2 is inconsistent with magmatic origin of the study deposit. On the one hand, the absence of skarn-related features and on the other hand, field observations, mineralogical and geochemical data, show that these manganese deposits were formed by the entry of manganese fluids with a volcanic origin in a sedimentary basin and then has reconcentrated and upgraded by regional metamorphism in mica schists and metamorphic limestone of the Khabr complex.