Sierra Madre Gold and Silver has commenced underground mining at the Coloso silver-gold mine, located within the producing Guitarra complex in Mexico. The mine was previously developed and mined by First Majestic Silver, and has over 12 kilometers of underground workings.
“This marks another milestone event in the restart of the Guitarra mine complex. The Coloso estimated resource grades are on average 1.7 times higher in silver and 1.2 times higher in gold compared to the Guitarra veins. As the widths of the veins vary from less than 1 meter to over 2 meters, ramp up mining will employ various mining methods and blasting techniques to determine the best combination of mining method costs versus grade dilution,” said Chief Operating Officer Greg Liller.
“In conjunction with processing of Coloso material, the company has hired a degreed metallurgist with extensive flotation experience as process plant superintendent. Their goal will be to determine the best ratio of Coloso to Guitarra mill feed material to achieve maximum economic benefit. During the ramp up of Coloso mining, various blending percentages for mill feed will be tested to ascertain best recovery procedures.”
Sierra Madre said mining has started on the Jessica vein system and stope development in the Joya Larga system is underway. Operations have commenced at a rate of 50 tonnes per day of mineralized material, and will ramp up to 150 tpd by year end.
Source: Sierra Madre