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Cosalá Operations

 The Cosalá mining district is located in the east-central portion of the state of Sinaloa, Mexico along the western edge of the Sierra Madre Occidental, an extensive tertiary volcanic province covering approximately 800,000 km2. It is accessible from the town of Cosalá via rural paved and dirt roads. All primary access roads can accommodate standard highway vehicles.

Mineralization in the Cosalá district is related to granodioritic or granitic intrusions emplaced between 140 and 45 million years ago into Cretaceous sedimentary rocks that overlie older basement terranes.

In 2015, production from the Cosalá Operations totaled 1.16 million silver ounces and 2.40 million silver equivalent ounces at a cash cost of $10.80 per ounce and an all-in sustaining cost of $14.89 per ounce.

Location Map

Cosalá Operations Map
 San Rafael



The San Rafael property hosts a zinc-lead-silver deposit and is located approximately 8km north of the Company's Los Braceros process plant. 

The San Rafael Project is expected to deliver average annual production of 1.0 million ounces of silver, 50 million pounds of zinc and 20 million pounds of lead over a 6 year initial mine life at negative AISC based on current reserves. The project has a pre-tax IRR of greater than 80% using current silver, zinc and lead prices.[1]


San Rafael is a brownfield development that will utilize certain existing infrastructure at the Cosalá Operations and is expected to have an initial capital cost of approximately $20 million using current exchange rates.[2] The Company targets commercial production in Q3 2017 following stockpiling of development ore starting in Q2 2017. The project is permitted for development and Environmental Impact Statement (EIS) approval has been received for an underground operation. Road access has already been completed and portal construction has begun. 

San Rafael-type mineralization consists of massive sulfides that occur at an unconformable contact between what is believed to be Tertiary volcanic tuff and Cretaceous limestone. Most of the massive sulfide mineralization appears to be hosted in the volcanic tuff. San Rafael contains silver, lead, and zinc mineralization with minor gold and copper. The main minerals are pyrite, pyrrhotite, sphalerite, and galena with minor marcasite, chalcopyrite, and magnetite. In the San Rafael Main Zone, this mineralization is often associated with quartz, sericite and pyrite alteration minerals. It has also been suggested that San Rafael displays many similarities to volcanogenic massive sulfide deposits, such as those found in the Guerrero Terrane in central Mexico. At San Rafael, a dacite tuff is the primary host for the mineralization. Part of the same area, the 120 Zone of San Rafael in contrast is hosted by skarn zones developed along dykes cross-cutting the underlying limestone units.

The San Rafael Prefeasibility Study is available here by clicking on the link and at A summary is available in the Company's Annual Information Form for the year ended December 31, 2015.


[1] The March 2016 Prefeasibility Study for the San Rafael Project adjusted for recent spot prices of $20.00 per ounce of silver, $1.01 per lbs. of zinc, $0.83 per lbs. of lead and 18.5:1 for the MXP:USD exchange rate.

[2] Pre-Feasibility pre‐production capital reduced from $22M using current exchange rates.

 Nuestra Señora
 Located in the Cosalá district, Nuestra Señora is a fully mechanized underground silver-zinc-lead-copper mine with the benefit of flexible mining methods and diversified metal production.

With a processing facility nearby, the operation has a capacity of 1,600 tonnes per day and permitted capacity for expansion to 4,000 tonnes per day. The plant produces zinc, copper and lead concentrates, with a significant silver component in the copper and lead concentrates. Concentrates are delivered to purchasers in Manzanillo, Mexico.


Mineralization at the Nuestra Señora mine occurs in four known deposits located within a 500m by 250m area - Nuestra Señora, Candelaria, Santa Teresa and Santo Domingo - which were originally developed and exploited from 1954 to 1965 by Asarco. Carbonate replacement-style mantos, veins, chimneys, chimney breccias, and mineralized exoskarn and endoskarn occur within limestone and granodiorite. Pyrite, sphalerite, chalcopyrite, galena, and lesser tetrahedrite are the dominant sulfide minerals.
 El Cajón
 El Cajón has considerable development in place following approximately $10 million in capital spending over the past three years. Permits are in place and the portal was collared in March 2014. More than 1,000 meters of ramp and lateral development has been completed to-date to provide access to upper stopes. Given changes in metal prices, the company expects to be back in production in 2017. The mine will operate temporarily as we transition fully to San Rafael ore.
 Other Projects

La Estrella

The Estrella operation currently comprises the removal of existing historic dumps and concurrent mapping and sampling. The previous operators apparently removed only higher grade, copper-rich material by hand sorting. The rejected material was piled in dumps. This material has sufficient silver, zinc, lead and copper to be processed at the company's mill. An operation of sampling, stockpiling and hauling this material to the mill is on-going. 

While removing the existing dumps an area of sulphide mineralization has been exposed in the walls of the existing workings. Company geologists are presently evaluating this showing to determine the deposit's potential grade and size.

La Verde

The La Verde area has been mined intermittently for over 10 years by a third-party operating under a royalty contract with the Company. While no historical drilling records or resource estimates are available, historical production data indicates that a consistent feed of approximately 120 grams per tonne silver and 0.3-0.5% copper was provided to a local processing plant. At the present time, the Company is focused on underground mapping and drilling to expand and better define known areas of mineralization.


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