Mineralogical Characteristics and Related Alteration Types in the Nabijan Ore Occurrence, East Azerbaijan, NW Iran

The Nabijan Cu-Au exposure is located in 20 Km southwest of Kaleibar. On the basis of structural classification it is situated in the zone of Alborz-Azarbaijan. The diorite-monzodiorite to gabbro-monzogabbro intrusive units of the area with Oligocene age, is intruded into the calcareous and volcanic rocks of the upper Cretaceous lead to metamorphism of the country rocks as well as the original body. Four hydrothermal zones including potassic, phyllic, silicification and tourmalization are recognized. Pyrite, native gold, chalcopyrite, arsenopyrite, sphalerite, chalcocite, malachite, azurite and hematite are present. Based on geochemical exploration studies and collection of 425 samples, the content of Cu varies from 41200 to 12 ppm. The average content of gold is 0.44 ppm. The formation and occurrence of Au and Cu mineralization are controlled by structural and geochemical ingredient.