Mining and Processing
Mining at the Segovia Operations is sourced from four underground mines using room and pillar or cut and fill mining methods, with the ore hoisted to the surface. Since 2017, the operation also incorporates the processing of ore provided by local informal miners through an artisanal mining model (ASM), which represented 12% and 16% of gold production in 2020 and 2021, respectively. These for-profit partnerships with community-based groups introduce two distinct operating cost structures at the Segovia Operations: owner-operated mining operations, and partner-operated mining operations. The partnership-operated mining operations cost structure primarily hinges on a percentage of the spot gold price since ASM partners are paid based on contained gold ounces delivered to the Maria Dama plant and using the LBMA gold spot price. Aris Mining currently has agreements with 63 third party ASM groups who mine in designated areas.
Ore is processed through the 2,000-tonne-per-day (tpd) capacity Maria Dama process plant using crushing, grinding, gravity concentration, gold flotation, concentrate regrinding, concentrate cyanidation, Merrill-Crowe zinc precipitation and refining of both the zinc precipitate and gravity concentrate to produce a final gold/silver doré product.
A new 200 tpd polymetallic processing plant was built in 2021 to recover zinc, lead, gold and silver from tailings to provide an additional source of cash flow from the mining operations. Tailings from the Maria Dama plant are treated through a filter press operation that produces dry stack tailings which are stored at the El Chocho tailings storage facility.