Deposit Types The Chipmo mineralization is of hydrothermal type with quartz infill. This deposit can be classified as epithermal Au-Ag veins associated with tellurides, with intermediate and low sulfidation. These structures are located in calc-alkaline rocks that are rich in potassium (Sarpane Volcanic). Veinhosting faults appear to be deep and crustal (Villon, 2011)The major recognized structures are the Prometida, Nazareno and Pucara Sur veins and correspond to the N60°E system. Mineralization In general terms, mineralization in the area of Orcopampa is associated to calderas with subvolcanic intrusives, dikes in Miocene tuffs (Swanson, 1998); in the Ocoruro-Jaspe area, mineralized structures are related to the Sarpane complex, faults, and possibly to subvolcanic bodies with more than one event or pulses of mineralization. Mineralization in Chipmo deposit is dominated by the occurrence of gold tellurides, mainly calaverite in high levels; petzite and hessite and native gold can be found in the central part. Copper sulfosalts and other gold-silver and bismuth tellurides occur subordinately. In general, mineralization is characterized by high Au/Ag ratios (>3) and low base metal concentrations, which are evident in the deep levels to the east. Its mineralogy is mainly composed of quartz in breccia, banded and replacement textures; there are also sulfides such as pyrite (leached), barite, gypsum, anhydrite and calcite. Alteration minerals include alunite, dickite, pyrophyllite, diaspore, kaolin, illite, smectite, chlorite, pyrite, etc. Types of Mineralization Mineralization in veins (Fracture Filling) The fractures originated through tectonism and movements of regional and local faults; they have been filled by hydrothermal solutions of rosary-type with irregular shapes and mineralogical filling, most of which is composed of sulfides, silicates in some sections of the veins, strands and tension fractures. Additionally, cavities (geodes) or open fractures are present, which allowed the percolation of meteoric waters that oxidized part of the mineralization. Mineralization is also found in shoots of different lengths and widths at the interception of veins or strands (sigmoids). Veins are persistent in trend and reach decametric to kilometric lengths. In some cases, outcrops are not continuous; they narrow to centimeters (rosary-type) and are also covered by Quaternary material. Structures are oriented and controlled by three main structural systems: E-W system, Lola, Florencia, Fresia structures (Jaspe Oeste Zone); Jaspe, Jaspe Sur structures (Jaspe Zone); Vanesa, Amparo, Ana 1, Paula, Irene, Aydé structures (Emilia Zone); Belinda, Blanca structures (San Jose Zone). NE system, the following structures belong to this system (anti-Andean): Ana, Olenka, Valeria 1 (Emilia Zone); Claudia, Carmín, Jossie structures, (Jasper Este Zone); Liliana structure (Huaylla Zone); Valeria, Vania, Escondida, Señal Chipmo structures (San Jose Zone); Estrella, Ada, Dorita, Sophia structures, Úrsula, Elizabeth, Paty, Esperanza, Prometida Norte, Prometida structures (Prometida Zone). NW system, part of the Andean system and belong to the strands of Jaspe vein (Jaspe Zone); Amelia, Alicia, Amparo structures (Jaspe Este Zone); Ocoruro Body with veinlets (Ocoruro Zone); Lorena Structure, (Chaqui Norte Zone); Karol, Dolly structures (Huaylla Zone). Mineralization in veinlets In the main structures, we have observed veinlets parallel to the main structures; others bifurcate from the main structure to the hanging wall and footwall; in the sigmoids there is evidence of tension veinlets between strands and between two main veins with a tendency to join; therefore, there are multidirectional stockwork-type veinlets filled with manganese oxides, calcite and in some cases, iron oxides. Mineralization in veinlets These are millimetric structures filled with gray quartz and calcite; they represent another stage of mineralization and may be related to gold mineralization. Mineralization in breccia bodies The mapped area shows evidence of breccia bodies formed by rounded or angular fragments from the same host rock (monomictic) or from foreign rocks, cemented with iron and manganese oxides with remnants of leached pyrite, quartz veinlets and presence of iron oxides (hematite).

Orcopampa mine has been conceptualized for a production level of 1,500 tpd; historically, mining was conducted using the overhand cut and fill (OCF) method with detrital fill (the excess waste is transferred to the surface dump): in recent years, mining has been carried out using sublevel stoping in some sectors. The mining method in Orcopampa’s underground mine is conventional and mechanized cut and fill (Breasting), this method is used to mine ore veins thickness from 0.8 to 5m. Mining is done by us and a service provider. The equipment used for development and exploration includes single-arm jumbos, bolters, scaler and scoop loaders (4yd3). The equipment used for conventional production are jacklegs, micro-electrical scoops (0.5-2yd3) and for mechanized are single-arm jumbos and diesel scoops loaders (2-4yd3). Ore haulage to surface is done with 20 and 35 m3 tipper trucks and 40m3 loading pocket in Nazareno’s and Prometida’s Shaft. Ore is taken to the process plant with 35 m3 tipper trucks. The applied method is OCF, which is a selective mining method that is executed based on established geomechanical conditions. The design starts from an auxiliary ramp, which will run on the footwall. There are tilting windows are positioned towards the vein to cut it perpendicularly. The slope of the windows will depend on the maximum gradient allowed by the equipment that circulates through them, which is generally +/-15% . When cutting the vein through the tilting window, the vein will be exploited along the entire length of the stope. At the operational level, the mine has been divided into five zones: Prometida, Nazareno, Pucará, Ocoruro, María Isabel. Operation areas are accessed through 3 ramps (Raul, Prometida, and Mario). Ore is extracted and transported to the surface through shafts system (one of them reach surface). From this point, ore is transported to the concentrator plant (located 7 km away) using 20 m3 trucks. The ore is transported from the production stopes to the shafts using trucks and a locomotive / mine car system. The mine currently maintains an average production level of 10,000 t per month throughout 2020. Mining methods at the Orcopampa mine The Orcopampa mine has historically applied the overhand cut and fill method in the different mineralized structures; a few years ago, the sub-level stoping method was implemented with the Bench and Fill variant, which is currently applied in a localized manner. According to rock mass geomechanical characteristics, geological conditions, and the predominant geometry of mineralized structures, a conclusion has been reached that both methods can be used in the different vein systems. The final decision on the mining method to be applied will be based on technical, operational, and economic evaluations. To establish the geomechanical design parameters of the mining method, sizing of both the overhand cut and fill method and the bench and fill method was performed. Mine backfill The filling begins when a stope cut is fully exploited. To do this, this area is covered with detrital material (in the case of Orcopampa), up to a distance less than the top of the work. This is because this area will serve as a free face for the next cut that is reached with a new shake.

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The Orcopampa processing facilities receive ore from multiple underground works and recover gold and silver in the form of dore bar and mineral concentrate. Orcopampa’s flowsheet includes two main processing lines: one that recovers the free gold using gravity concentration followed by merrill-crowe, and the second, which leaches the finely ground ore and recovers precious metals using a combination of merrill-crowe for high concentration solutions and carbon-in-leach followed by electrowinning for low concentration solutions. All recovered precious metals are smelted together to produce a dore bar. Tailing from the carbon-inleach are subject to a final recovery stage using flotation to produce a concentrate rich in gold and silver that is trucked off site. Agitated Leaching & Merrill-Crowe The overflow stream from hydrocyclones in the grinding stage feeds a trash screen before slurry is pumped to the agitated leaching stage where cyanidation is performed in six mechanically agitated ........