(Translated from Spanish by Google Translate)
Currently, four underground mines operate: San Cristóbal, Carahuacra, Andaychagua and Ticlio, whose extracted ore is treated in two concentrator plants, Victoria and Andaychagua, with an installed capacity of 8,650 tpd. The Mahr Tunnel Plant with a capacity of 2,750 tpd is in care & maintenance.
The main mining methods used are Sub-level Stoping and Over Cut and Fill, while the Under Cut and Fill and SARC methods are also applied in some areas.
San Cristobal Mine
There was a 1% increase in the Zn head grade. However, the law was reduced head of the other metals: 7% in Pb, 9% in Cu, 8% in Ag, due to the delays in the primary developments of 2020 as a consequence of covid-19, which caused the pits scheduled for 2021 had a lag in their exploitation, mainly in the Split 658 vein, the main contributor in volume and grade.
Ore production was 48% higher than in 2020, the results of production of fines in zinc, lead and silver were above in relation to 2020 in 53%, 38% and 36%, respectively.
Sub-level stoping is utilized as a primary mining method.
Exploration was directed towards the lateral areas of the Ramal Piso 722 veins, vein 658 and Split 658 vein at levels 820, 1320 and 1420, with favorable results.
Andaychagua Mine
There was an increase in the head grades of Zn in 20%, Pb in 21% and Cu in 23%, due to the planned contribution of the Salvadora minerali ........
