MALPASO MILL
[Overview]
In mid-September, 2005, Dia Bras Mexicana, a wholly-owned Mexican subsidiary of Dia Bras, acquired control of the Malpaso mill, which it had been operating since March, 2005. During 2007, the Corporation upgraded the mill to 800 tonnes per day (tpd) through installation of a second, 550 tpd circuit.
The original Malpaso mill was a flotation plant, and gravity recovery circuits have been added to the original circuit. The new Triunfo circuit utilizes flotation recovery and was added to treat mineralized rock from the Cusi mines. Currently, the production from the Bolivar and Cusi pilot-mining programs runs at a rate of 8,500 tonnes per month.
The Corporation completed construction of a cyanide vat leach circuit with a Merrill Crowe recovery system, in late 2009, and has achieved 80-85% recovery of silver with the combined flotation and cyanide leaching methods. Dia Bras poured its first silver doré from Cusi mine material in December. The Malpaso mill has the capacity to process approximately 24,000 tonnes per month of material from Dia Bras’ pilot-mining projects.