The hydrometallurgical treatment of Farallon Resource’s Campo Morado bulk Zn-Pb-Cu-Ag-Au sulfide concentrate

Farallon Resources Limited is a mineral exploration company focused on the exploration and development of the 100% owned Campo Morado precious-metals-rich massive sulfide deposit in Guerrero State, Mexico. The Campo Morado district hosts 16 known sulfide deposits and has identified approximately 29 million tonnes of massive sulfide mineralization across four deposits. Among this, a higher grade inferred resource of 9.2 million tonnes at 4.08% Zn, 0.79% Cu, 1.29% Pb, 3.34 g/t Au, and 176 g/t Ag is contained. The Campo Morado massive sulfides present mineralogical complexities that hinder the effective separation into high-value Cu/Zn and Pb concentrates via traditional flotation methods. This study explores a hydrometallurgical alternative, which includes: (1) flotation of a bulk concentrate rich in copper, zinc, and precious metals; (2) partial autoclave oxidation for leaching zinc and copper and facilitating cyanidation; (3) recovery of zinc and copper via SX/EW for premium products; and (4) lime boil treatment to make silver more leachable, followed by cyanidation. Progression from bench-scale work to integrated pilot plant testing will be detailed, alongside the final flowsheet design results.