Overview
Stage | Production |
Mine Type | Underground |
Commodities |
|
Mining Method |
- Mechanized Cut & Fill
- Longhole stoping
- Resue mining
- Unconsolidated hydraulic fill
|
Production Start | ... |
The Valenciana Mine Complex (VMC), formerly known as the Guanajuato Mine Complex includes the Guanajuato and San Ignacio operations, the Cata processing plant and associated infrastructure.
The San Ignacio Mine is located approximately 7 km west of the VMC Guanajuato operation, within a separate mineralizing system. San Ignacio mineralized material is processed at the Cata facility.
San Ignacio was placed on care and maintenance effective early January 2022 and recommenced production in August 2022. |
Source:
p. 11,12
On August 4, 2022, Guanajuato Silver acquired 100% of Great Panther Mining’s Ltd.’s Mexican subsidiary, Minera Mexicana Rosario S.A. de C.V. which holds the Valenciana Mine Complex. Minera Mexicana El Rosario, SA de C.V. operates the Valenciana Mine Complex.
Contractors
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Deposit Type
- Vein / narrow vein
- Epithermal
Summary:
The primary deposit type of interest at the San Ignacio Property is low sulphidation epithermal silvergold mineralization.
San Ignacio is underlain by a monotonous package of basalt (Kbas) and andesite (Kanlf) volcanic rocks belonging to the lower Cretaceous La Luz andesite (Randall et al., 1994; Stewart, 2006; Baker, 2011). 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.
Andesite is generally massive to locally feldspar-phyric to laminated (very rarely) and was probably formed by accumulation of a series of extrusive flows and ash falls.
Locally, these volcanic rocks have interbeds composed of sandstone, siltstone, or fine, pale ash layers (generally sericite-quartz). 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 San Ignacio Property, and both are quite rare. In the northern part of San Ignacio, a few fine-grained 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 si ........
Mining Methods
- Mechanized Cut & Fill
- Longhole stoping
- Resue mining
- Unconsolidated hydraulic fill
Summary:
Valenciana Mine Complex (VMC, formerly known as the Guanajuato Mine Complex or GMC) comprises the Guanajuato and San Ignacio operations. Typically, all zones at the VMC are extracted by the Cut & Fill mining method.
Continuing operations at VMC will be achieved through the backfilling of tailings underground using a hydraulic fill system that will make use of select voids and open stopes that have been created at VMC over the past 450 years of underground mining.
The Guanajuato Silver will benefit from increased operational efficiency through the use of the newly refurbished StopeMate as the Guanajuato Silver can now employ longhole stoping as a mining method where appropriate.
Longhole stoping is used to extract mineralized material from an underground mine by drilling a pattern of closely spaced, parallel holes into the mineralized material and then blasting the mineralized material between the holes. The StopeMate drill is designed to drill these closely spaced, parallel holes quickly and efficiently from a single position. This ensures that the holes are drilled straight and parallel, which is important for extracting mineralized material more effectively, with less dilution and lower costs. The long hole drill is commonly used for underground bulk mining which will be applied in stopes over 1.5 meters in width, this will allow the Guanajuato Silver to increase production in approximately 25% of the production areas of the mine.
Flow Sheet:
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).
Flow Sheet:
Summary:
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Source:
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Reserves at September 30, 2023:
Costs are US$40.0/t for mining, US$16.0/t for processing, and US$18/t for G&A, leading to a 120 g/t AgEQ reporting cutoff grade.
Category | Tonnage | Commodity | Grade | Contained Metal |
Measured & Indicated
|
790,000 t
|
Silver
|
123 g/t
|
3,136,000 oz
|
Measured & Indicated
|
790,000 t
|
Gold
|
2.1 g/t
|
53,000 oz
|
Measured & Indicated
|
790,000 t
|
Silver Equivalent
|
300 g/t
|
7,621,000 oz
|
Inferred
|
2,166,000 t
|
Silver
|
127 g/t
|
8,877,000 oz
|
Inferred
|
2,166,000 t
|
Gold
|
2.27 g/t
|
158,000 oz
|
Inferred
|
2,166,000 t
|
Silver Equivalent
|
318 g/t
|
22,167,000 oz
|
Corporate Filings & Presentations:
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