101 Gold Deposit, Eastern Azarbaijan, Iran
101 Gold deposit (as defined below) located in Arasbaran portion of the Azarbaijan state, Iran. The executive operation of gold exploration commenced in August 4th of 2015 by Atin Madan Midia company (AMMCO).
101 Gold deposit is located 25 kilometers (km) north-east of Ahar. The study area is 34.5 square kilometer Consist of the main target rectangle A0 and other exploration targets: A1, A2, A3, A4, A5, A6, and A7
Road construction for 14 kilometers
A total of 300 surface sampling
Geophysical surveys in the number of 3200 points using IP-RS method
Geological maps of the area in the scale of 1:20,000; 1:5,000 and 1:1000
The 226 boreholes in 8200 m drilling, the number of 2200 sample from core drilling
The 281 trenches in more than 15000 cubic meters and the number of 3031 sampling
Geological setting
101 epithermal gold deposit is located to the west of the Cenozoic Alborz-Azarbaijan magmatic belt in NW Iran. The geology of deposit composed with a set of upper Eocene volcanic rocks of acidic to intermediate that has a dominant lithology of andesite porphyry, andesite-basalt, basalt and rhyodacitic rocks accompanying with pyroclastic (Lithic-tuff with acidic composition). Its petrological characteristics can be investigated as of the Arasbaran magmatic evolution. The volcanic complex in the north of the Goshe Dagh batholith influenced by hydrothermal activity due to the mass of monzonite and dykes that altered by silica, phyllic, argillic, advanced argillic and propylitic. The hydrothermal fluid circulation along fractures and faults in the region caused alteration in addition to deposition of metallic minerals and mineralization. The geological map of the target areas has been prepared separately and all modified in one geological map below
101 epithermal gold deposit is located to the west of the Cenozoic Alborz-Azarbaijan magmatic belt in NW Iran. The geology of deposit composed with a set of upper Eocene volcanic rocks of acidic to intermediate that has a dominant lithology of andesite porphyry, andesite-basalt, basalt and rhyodacitic rocks accompanying with pyroclastic (Lithic-tuff with acidic composition). Its petrological characteristics can be investigated as of the Arasbaran magmatic evolution. The volcanic complex in the north of the Goshe Dagh batholith influenced by hydrothermal activity due to the mass of monzonite and dykes that altered by silica, phyllic, argillic, advanced argillic and propylitic. The hydrothermal fluid circulation along fractures and faults in the region caused alteration in addition to deposition of metallic minerals and mineralization. The geological map of the target areas has been prepared separately and all modified in one geological map below
Mineralization and alteration
At 101 area, the Au mineralization is hosted by silica veins. The mineralization is low-sulphidation epithermal and is characterized by a variably altered argillic (silica-clay) zone containing milky quartz-pyrite (changed to limonite) veins and pyrite-bearing silicified hydrothermal breccia. The vein quartz can be coarsely crystalline and sometimes exhibit cockade textures. Malachite has been noted at vein zone which reinforces the belief that the deeper part of the hydrothermal system is exposed similar to Sarilar area, where gold mineralization occurred in hydrothermal system. It is also observed that the Au mineralization is sometimes in the quartz veins and sometimes in the surrounding wall rocks which is accompanying copper sulfides and oxides. This can be explained mainly by supergene processes which probably mechanically moved the hypogene Au from the veins to the wall rocks. Most likely in the hypogene environment, all the Au will be contained in the vein quartz and hydrothermal breccias. A view of mineralization in veins is shown in microscopic images below. Pyrite is the main ore mineral, associated with minor chalcopyrite, covellite, bornite, and trace molybdenite in both prospects. Gold occurs mostly as microscopic grains in quartz and pyrite. Silica occurs as grey, white, and clear quartz, as well as amorphous silica. The main textures displayed by the vein materials include massive, crustiform banding, vuggy, and breccia. The country rocks at 101 was variably affected by regional argillic, propylitic and silicic alterations prior to the vein formation. The alterations are common features in volcanic and pyroclastic rocks in the Arasbaran zone; argillic alteration has locally resulted in the development of workable deposits of clay minerals.
At 101 area, the Au mineralization is hosted by silica veins. The mineralization is low-sulphidation epithermal and is characterized by a variably altered argillic (silica-clay) zone containing milky quartz-pyrite (changed to limonite) veins and pyrite-bearing silicified hydrothermal breccia. The vein quartz can be coarsely crystalline and sometimes exhibit cockade textures. Malachite has been noted at vein zone which reinforces the belief that the deeper part of the hydrothermal system is exposed similar to Sarilar area, where gold mineralization occurred in hydrothermal system. It is also observed that the Au mineralization is sometimes in the quartz veins and sometimes in the surrounding wall rocks which is accompanying copper sulfides and oxides. This can be explained mainly by supergene processes which probably mechanically moved the hypogene Au from the veins to the wall rocks. Most likely in the hypogene environment, all the Au will be contained in the vein quartz and hydrothermal breccias. A view of mineralization in veins is shown in microscopic images below. Pyrite is the main ore mineral, associated with minor chalcopyrite, covellite, bornite, and trace molybdenite in both prospects. Gold occurs mostly as microscopic grains in quartz and pyrite. Silica occurs as grey, white, and clear quartz, as well as amorphous silica. The main textures displayed by the vein materials include massive, crustiform banding, vuggy, and breccia. The country rocks at 101 was variably affected by regional argillic, propylitic and silicic alterations prior to the vein formation. The alterations are common features in volcanic and pyroclastic rocks in the Arasbaran zone; argillic alteration has locally resulted in the development of workable deposits of clay minerals.
Major styles of mineralization in 101 deposit. (A) Mineralization of pyrite, chalcopyrite, covelite and chalcocite (cupper ores) are seen in this section that mostly drilling of S6 and S5 contain of this minerals. All these minerals indicate high-temperature mineralization. (B) Indicative minerals of phyllic alteration (quartz, sericite and pyrite) accompanied by pyrophyllite are seen in this section which is indicates of high temperature mineralization (370 degrees centigrade). (C) Pyrite, Chalcopyrite and tetrahedrite are seen in this section as well. (D) Inclusions of galena and tetrahedrite are observed in chalcopyrite. (E) Chalcopyrite cupper ore observed in pyrite fractures which shows a lateness of chalcopyrite compare to pyrite
Mineral Processing Test
A total of 200 kilograms in 4 bag of 50 kg packs were taken from A0 surface sample, which were totally from oxide mineralization zone. The average grade of Au: 2.6 ppm
The average recovery of 52% and 33% for gold and copper respectively by heap leaching test. The optimization results of tank leaching test achieved in Table below.
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