The San Ignacio property is underlain by a monotonous package of basalt (Kbas) and andesite (Kanlf) volcanic rocks belonging to the lower Cretaceous La Luz andesite (Randall R. et al., 1994; Stewart, 2006; Baker, 2012). The basalt generally has subtle to well-developed pillow structures that are locally flattened. In a few localities, inter-pillow hyaloclastite is present and is characterized by a fine breccia composed of devitrified glass shards in a fine groundmass. Primary layering and tops-up indicators are generally difficult to determine from the small outcrops typical of the property, but according to Stewart (2006), the San Ignacio property stratigraphy is not overturned. Locally, these volcanic rocks have interbeds composed of sandstone, siltstone, or fine, pale ash layers (generally sericitequartz). A more coarse-grained felsic (possibly dacite) unit is exposed northwest of the San Jose mine in the southern part of the property. Where observed, bedding is generally shallowly dipping. Two types of dykes are present on the property, and both are quite rare. In the northern part of the property, a few finegrained mafic dykes are exposed and preserve foliation and fractures like the host volcanic rocks, so these dykes are probably quite early. Fine-grained felsic dykes occur locally near the Veta Nombre de Dios structure, and are generally moderately silicified with minor fine-grained pyrite. The most important phase of mineralization in the Guanajuato district cons ........

The Guanajuato Mine Compleex (the “GMC”) comprises the Guanajuato and San Ignacio operations. Typically, all zones at the GMC are extracted by the Cut & Fill mining method.

The mining method is mechanized cut and fill, with fill provided by waste development. Jacklegs are used in stopes for vertical to 70 degree production holes, and if necessary the hanging wall can be blasted to create a 2.0 m wide stope.

The mining at San Ignacio began in the third quarter of 2013. The bulk of the 2021 mining is on the Nombre de Dios zones, with lesser production from Melladito South and Intermediate zones, and initial development in the Purisima zone.

Workers operate on three 8-hour shifts from Monday to Saturday. Four separate contractors operate the development and production of the mine. The contractors provide supervisors, and the company provides supervisors and a superintendent to over seen the operation. In addition, there is a services team and a security team.

Cut and Fill mining is used to extract material defined by mining blocks. The main ramp (4.5 metres wide by 4.5 metres high) has a slope of 12%. It was developed using a single-arm electric Jumbo, a 6 yard Scoop Tram, and a combination of conventional 20-tonne trucks and an underground truck.

The mineralized rock is transported by truck to the Cata plant using conventional 20-tonne trucks.

Crushing & Grinding Circuits
The ore from the 1,000-tonne capacity hopper is transferred along a 48-inch-wide belt to a 24 inch by 36-inch PettiBone jaw crusher where the 12-inch feed is reduced to less than 3-inch diameter. The feed from the jaw crusher exits along a 36-inchwide belt and feeds a 6 ft wide by 20 ft long double bed vibrating Ludowici screen. The Ludowici screen separates the feed by size with the upper bed separating material greater than 1 inch and the lower bed separating material less than ¼ inch. This ¼ inch “fine” material is then fed along a 24-inch belt to a hopper prior to grinding (currently feed on average of 88% less than ¼ to the mill). The over size from the Ludowici screen is fed to a Metso (300HP) secondary cone crusher for further size reduction which is then fed back to the Ludowici screen along a 24-inch belt to ensure the material is the appropriate size for the mill. The crushing circuit has a backup Simmons 5½ short head cone crusher that is utilized as needed.

Milling
Immediately after the crushing, the ore is stored in a series of "fines hoppers" which has a capacity of 1,800 tonnes. This material passes through chutes at the bottom of the hopper to feed three 24-inch-wide belts where the material is weighed (continuous weighing scale) and fed into three twin Denver of 7 ft by 14 ft ball-mills which are coated inside by a chromiummolybdenum alloy shield on the surface of the cylinder and natural rubber on the "heads". The grinding material used in these mills are 2.5-inch diameter high chrome alloy cast balls. The ¼ inch crushed material enters the ball mill where the movement, impacts and attrition from the balls promotes the wet pulverization of the mineral which is discharged by the mill as a "thick mineral pulp" where approximately 70% of the material by weight is solid and the remaining 30% is water. This thick mineral pulp is then diluted by adding water and feeds into 4 by 3-inch Krebs pumps where the material then feeds a series of Gmax G10 hydro-cyclone classifiers (two cyclones per mill) which carry out the classification of fines before entering the flotation circuit (75% of the material passing minus 200 meshes with automatic sampling). The average content of this material is 28% solid by weight and 72% water. The oversize material is returned to the mill for re-grinded in the closed circuit which has a "circulating load" of 350% thus ensuring the best release of the particles of interest. At this stage of grinding, reagents are added as the ore entersthe mills. This includes the addition of two specific reagents which promote the recovery of gold and silver (promoter MaxGold 900 and promoter 7310, both Cyteg brand products).

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