The mineral deposits in the Guanajuato area are classic fissure-hosted low-sulphidation epithermal gold-silver-bearing quartz veins and stockwork.

Mineralization
The most important phase of mineralization in the Guanajuato district consists of epithermal silver-gold veins contained within northwest-trending, Cenozoic-age faults. La Luz structure consists of numerous mineralized fractures in a northwesterly trending orientation, which extends for a known strike of approximately 8 km long. Historically productive veins on the property include Veta Melladito, and Veta Purisima. Veins identified in the recent Great Panther drilling are the Melladito, Melladito BO, Intermediate, Intermediate 2, Nombre de Dios, Nombre de Dios 1.5, Nombre de Dios 2N, Nombre de Dios 2S, Nombre de Dios 3, Melladito South, 700, 711, 740, Purisima, Purisima HW, Purisima Int., Purisima Bo, and Santo Nino. Mineralization is contained within tabular veins, vein stockwork, and breccias. The eighteen veins with structural continuity inferred from surface mapping and diamond drilling from surface, and now with extensive underground development, have been defined up to 2,200 meters along strike and 150 meters down dip. The Melladito and Intermediate veins (5) are very steeply dipping, the Nombre de Dios veins (5) are shallowly dipping (45-50 degrees west) and are likely offshoots of the Intermediate veins, and the Purisima veins (8) are shallowly dipping at 45-50 degrees to the west. The veins ........

San Ignacio
The most important phase of mineralization in the Guanajuato district consists of epithermal silver-gold veins contained within northwest-trending, Cenozoic-age faults. La Luz structure consists of numerous mineralized fractures in a northwesterly trending orientation, which extends for a known strike of approximately 8 km long. Historically productive veins on the property include Veta Melladito, and Veta Purisima. Veins identified in the recent Great Panther drilling are the Melladito, Melladito BO, Intermediate, Intermediate 2, Nombre de Dios, Nombre de Dios 1.5, Nombre de Dios 2N, Nombre de Dios 2S, Nombre de Dios 3, Melladito South, 700, 711, 740, Purisima, Purisima HW, Purisima Int., Purisima Bo, and Santo Nino. Mineralization is contained within tabular veins, vein stockwork, and breccias. The eighteen veins with structural continuity inferred from surface mapping and diamond drilling from surface, and now with extensive underground development, have been defined up to 2,200 meters along strike and 150 meters down dip. The Melladito and Intermediate veins (5) are very steeply dipping, the Nombre de Dios veins (5) are shallowly dipping (45-50 degrees west) and are likely offshoots of the Intermediate veins, and the Purisima veins (8) are shallowly dipping at 45-50 degrees to the west. The veins are accompanied by hydrothermal alteration, consisting of argillic, phyllic, silicic, and propylitic facies.

The Melladito vein is a steep east dip v ........

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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