Discovery Silver (TSCV: DSV; OTC: DSVSF) reports excellent metallurgical test results from its Cordero silver-lead-zinc project in Chihuahua State, Mexico. The recent locked-cycle flotation test work undertaken for the prefeasibility study (PFS) is the most comprehensive such work done for the project.
Tests were performed on several types of samples. Those with the highest grades had recoveries of 94% to 98% silver, 89% to 97% lead, and o92% to 96% zinc. Medium-grade samples of blended rock types had recoveries of 83% to 92% silver, 84% to 92% lead, and 81% to 89% zinc. When oxide and sulphide samples were blended, oxide-specific recoveries were 60% silver, 40% lead and 85% zinc via flotation. (Floating the oxide material eliminates the need for heap leaching at Cordero.) These results were higher than recoveries assumed for the 2021 preliminary economic assessment.
Discovery expects to produce a lead-silver concentrate (>40% lead and >1,500 g/t silver) and a zinc concentrate (>50% zinc) for sale.
The processing plant will be built in stages, according to the PFS. First will be a single-stage semi-autogenous (SAG) circuit consisting of a single-gyratory crusher, a single SAG mill, and flotation. It will have a capacity of 25,000 t/d. The second phase expansion will add a ball mill and parallel flotation circuit, bringing capacity up to 50,000 t/d. This plan is less complicated that that proposed by the PEA in that it eliminates heap leaching and three-stage crushing.
Further details about Cordero are posted at www.DiscoverySilver.com.