Americas owns the San Rafael and nearby Nuestra Señora and El Cajón deposits, which are located in the Cosalá mining district. Silver, lead, zinc, copper, and gold occur in a variety of deposit types within the district, including skarns, carbonate replacement deposits, breccia deposits, and massive sulfides.

The Nuestra Señora property lies within a sub-circular inlier of Cretaceous limestone approximately 10km in diameter situated in the eastern part of the 139 to 45 Ma-old Sinaloa Batholith. Contact metamorphism of the limestones created re-crystallized limestone, marble, and skarn. Initial skarn development in the area was contemporaneous with emplacement of the batholith; however, there were several pulses of magmatic and hydrothermal activity. Carbonate replacement-style mantos, veins, chimneys, chimney breccias, and mineralized exoskarn and endoskarn occur within limestone and felsic and lesser mafic intrusions. Pyrite, sphalerite, chalcopyrite, galena, and lesser tetrahedrite are the principal minerals.

In the San Rafael-El Cajón area, Cretaceous limestone, commonly recrystallized and marbleized but only locally skarn-altered, is exposed within windows in Tertiary volcanic rocks. Massive sulfide mineralization at San Rafael occurs primarily along the contact of dacite tuff with Cretaceous limestone, with additional mineralization within the dacite in the Upper Zone and within skarn-altered limestone in the 120 Zone. The protolith at El Cajón is altered limestone, thought to be of Cretaceous age. 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. The El Cajón-type of mineralization, also seen within the San Rafael deposit’s 120 Zone, is related to skarn alteration of calcareous sediments and occurs as both mantos and chimneys. It consists of silver-coppergold mineralization in the form of chalcopyrite and tetrahedrite with minor pyrite, galena, sphalerite, arsenopyrite, chalcocite, jalpaite, native silver, copper, and bismuth.

The Cosalá Operation consists of the Nuestra Señora silver-zinc-copper-lead mine, the San Rafael silver-zinc-lead mine, the El Cajón mine, the Zone 120 silver-copper exploration project, the Los Braceros plant. The Company declared commercial production in January 2009 following development of the Nuestra Señora mine and associated commissioning of the Los Braceros processing facility. In December 2017 commercial production was declared at the San Rafael mine and the Nuestra Señora mine was placed on care-and-maintenance. The El Cajón mine is currently on care and maintenance.

The EC120 Project considers underground mining at both the El Cajón and Zone 120 deposits.

EC120 is a viable project ready for development. A production decision has not yet been made, however, permits are in place. Processing of material from EC120 is expected to start after the cessation of production from San Rafael.

Nuestra Señora underground mine development commenced in 2005, and prior to the commissioning of the process plant in May 2008, approximately 87,000 tonnes of ore had been stockpiled on surface. Since attaining commercial production of the process plant in January 2009, the Nuestra Señora mine has been the sole source of ore feed for the plant. Mining at Nuestra Señora uses mechanized mobile mining equipment, principally twin-boom jumbos, 6yd3 scoop trams, production drill rigs, and rigidbody highway trucks.

Complex geometries of the mineralized bodies make it imperative to employ high-density definition drilling techniques to determine the extents of the mineralization. During development, ore-control definition is performed by drilling 12m long holes on approximately 4m centers. Samples are taken from the cuttings of each 1.5m of drill steel and are assayed in the operation’s laboratory. This detailed sampling control allows for more appropriate development, improving mining recovery and minimizing dilution.

As successive levels are developed, each mineralized body is tested for continuity and size. The mining method employed for each mineralized body is determined by its geometry. Predominantly long-hole or cut-and-fill stoping is designed for production; however, shrinkage stoping via hand-held air-leg drill mining is available for implementation where warranted.

Waste rock from access development is used as fill material in successive cut-and-fill lifts and exhausted long-hole stopes. Tailings are recovered from the Nuestra Señora process plant and delivered by truck to exhausted long-hole stopes for use as fill along with development waste rock.

In December 2017, the Nuestra Señora mine was placed on care andmaintenance. Production from the Nuestra Señora mine has stopped although a resource remains at the property.

The San Rafael mine started project construction activities in September 2016 and has been in commercial production since December 2017. The Mineral Reserves support a mine life of five years. The underground mine is accessed by a decline that portals at surface near the southern portion of the deposit where the surface infrastructure is located. A series of ramp systems from the main decline provides access to the various stoping areas of the deposit.

The main decline has reached the bottom of the defined Mineral Reserves in the Main Zone and ramp development to access the Upper Zone has commenced. Due to the depth, shallow-dipping angle and variable thickness of the mineralization, the mining method used at San Rafael is postpillar cut and fill. Stopes are accessed from a primary stope access driven at a -15% decline. After mining of each successive 5m high cut of ore, the stope is backfilled and the access “backslashed” to allow for mining of the next cut. This sequence is repeated up to five times until the stope access reaches an incline of +15%. Access to the next cut is then provided by a -15% stope access driven from a higher elevation.

The LOM plan anticipates that the post-pillar cut and fill stopes will be backfilled with unconsolidated development waste and waste generated from a waste quarry. Given the use of unconsolidated backfill, the mining sequence is typically from the bottom up.

Primary mine ventilation is provided via two vertical bored raises and the main decline. A main exhaust fan is located underground at the northern end of the deposit and fresh air is pulled through a central intake bored raise and the main decline. Fresh air is provided to the working development faces and stoping areas by use of secondary fans and ducting.

The primary mining method at the San Rafael mine is post-pillar cut and fill.

The mining method at San Rafael (post-pillar cut and fill) relies on leaving continuous vertical insitu pillars to provide additional support in areas where the ore zone is wider than 8m in width. These pillars are nominally 6m by 6m in dimension. Placement of these pillars is initially planned for low grade areas of the deposit but due to the need of vertical continuity, they will potentially be placed in areas with higher grades.

The Los Braceros process plant is a conventional polymetallic concentrator currently configured to produce zinc and lead concentrates. Throughput has recently been approximately 1,750 tonnes per operating day.

Key processing equipment currently installed at the Los Braceros plant includes:
• Three-stage crushing plant; 0.76m x 1.07m jaw crusher, 1.67m standard cone crusher, 1.67m shorthead cone crusher;
• 800 tonne fine ore bin;
• Primary grinding mills: two each, 3.0m x 3.2m, 600kW;
• Concentrate regrind mill; one VXP500 vertical mill;
• Wemco 300ft3 rougher trough cells (lead and zinc);
• Wemco 10m3 rougher tank cells (zinc);
• Galigher Agitair 54C x 40 and Denver Sub-A cleaner cells (lead and zinc);
• Four each 2.44m diameter x 3.65m drum filters;
• Bins and hoppers;
• Related support equipment – tanks, pumps, blowers, feeders, and instrumentation; and
• Engineered tailing storage facility.

San Rafael ore has been the exclusive feed for the Los Braceros plant since November 2017.