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 inclu ........

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 tiltin ........

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