Overview
Stage | Preliminary Economic Assessment |
Mine Type | Underground |
Commodities |
|
Mining Method |
|
Mine Life | 6 years (as of Jan 1, 2018) |
Source:
p. 66
Apex Silver Mines Corporation, a subsidiary of Apex Silver Mines Limited, acquired the initial interest in the Project in 2004. The Project interest was held by the wholly indirectly-owned subsidiary Silex Argentina S.A. Following reorganization under Chapter 11 bankruptcy in 2009, the assets of Apex Silver were transferred to Golden Minerals Company. As part of that transaction, Silex Argentina became a wholly indirectly-owned subsidiary of Golden Minerals.
Contractors
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Summary:
The Yaxtché deposit shows alteration assemblages typical of high sulfidation epithermal deposits whereas the metal content and sulfide assemblages are characteristic of mineralizing fluids with an intermediate sulfidation state.
The transition from high- to intermediate-sulfidation state is thought to define an evolving epithermal system as high-sulfidation state metal-bearing fluids cooled and interacted with host rocks as they moved vertically and laterally though the Yaxtché structure. This is depicted with three stages of primary fluid evolution:
• Alteration and gangue mineral assemblages related to acidic magmatic–hydrothermal fluids created permeability through acid leaching (i.e. vuggy silica)
• High-sulfidation state mineral assemblages (namely enargite–luzonite–famatinite) and metal contents (copper–gold dominant) formed at lower elevations within the Yaxtché structure
• Transition of high- to intermediate-sulfidation state as metal-bearing fluids ascended and further interacted with host rocks. The final phase of fluid evolution was critical for precipitation of silver-bearing minerals as tennantite–tetrahedrite became stable.
Sillitoe and Hedenquist (2003) defined the following key features of intermediatesulfidation systems:
• Intermediate-sulfidation deposits occur in calc-alkaline andesitic–dacitic arcs, although more felsic rocks can locally act as mineralization hosts
• The arcs typically display neut ........

Summary:
Preliminary work was performed on four possible mining systems: post-pillar cut-andfill, transverse with pillars, transverse with cemented fill, and sublevel with end slicing.
The post-pillar cut-and-fill mining method was selected for the PEA evaluation.
This mining method relies on using 5 m x 5 m rooms and 5 m x 5 m square pillars. The pillars of one level are planned to align vertically with the next mining level to provide support. Mining starts at the lowest elevation in a mining area and is completed working upward. Some pillars can be extracted when they occur in an area of the stope where there will be no mining above.
Productivity calculations and unit costs for the final selection of a post-pillar cut-and-fill mine plan are based on the following criteria:
• Two 10 hr shifts per day, which yield 16 hr of actual work time
• The ground is considered medium–hard for the drilling and blasting variable
• Drilling of 18 ft (5.5 m) holes (providing 16.6 ft (5.1 m) of advance) with a two-boom production jumbo. Hydraulic drifter (drill) penetration rate is assumed to be 3.5 ft/min (1.1 m/min)
• No standard ground support is indicated; however, 1.5 hr per cycle is allotted for ground control (e.g. rock bolting), spot bolting or other cycle interruptions
• Blasting will be carried out using gelatin-class dynamite and ammonium nitrate/fuel oil (ANFO) as the primary blasting agent. Non-electric (non-el) type de ........

Flow Sheet:
Flow Sheet:
Summary:

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Projected Production:
Commodity | Product | Units | Avg. Annual | LOM |
Silver
|
Concentrate
|
kt
| | 78 |
Silver
|
Payable metal
|
koz
| | 27,572 |
Silver
|
Metal in concentrate
|
koz
| 4,837 | 29,023 |
Silver
|
Metal in ore
|
koz
| | 32,192 |
Operational Metrics:
Metrics | |
Daily mining rate
| 1,400 t * |
Daily ore mining rate
| 1,200 t * |
Ore tonnes mined, LOM
| 2,447 kt * |
Daily processing capacity
| 1,200 t * |
Annual mining rate
| 420,000 t of ore * |
Mining scale, tpd
| 1,400 t |
Processing scale, tpd
| 1,200 t |
* According to 2018 study.
Reserves at February 26, 2018:
The base case Mineral Resource model reported at a 250 g/t Ag cut-off.
Category | Tonnage | Commodity | Grade | Contained Metal |
Indicated
|
2.93 Mt
|
Silver
|
482 g/t
|
45.3 M oz
|
Inferred
|
0.31 Mt
|
Silver
|
417 g/t
|
4.1 M oz
|
Mine Management:
Job Title | Name | Profile | Ref. Date |
.......................
|
.......................
|
|
Apr 8, 2022
|
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Staff:
Total Workforce | Year |
|
2021
|
Corporate Filings & Presentations:
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