Name of the Mine
Galena Complex.
Location
In Idaho’s prolific Silver Valley, in the US.
Mine Owner/s
Americas Gold and Silver (60%) and Mr Eric Sprott (40%).
Brief Description
The Galena Complex comprises the operating Galena mine, the Galena processing plant, the Osburn tailings impoundment, the idle Coeur mine, the Coeur processing plant (currently on care and maintenance) and the Caladay exploration property.
Brief History
The Galena Complex has more than 50 years of operating history.
The Galena mine dates back to 1887, but its modern history and mining started in 1947. From 1953 to 2013, the Galena mine primarily mined silver/copper ore, with minor production of silver/lead ore. Silver/lead ore became the predominant ore type in 2014.
The Coeur mine shaft was collared in 1963. The mine produced continuously from 1976 to 1991, and from 1996 to 1997. Coeur was put on care and maintenance from 1997 to 2007, when rehabilitation work started on the Coeur mine 3400 Level and, later, the Coeur shaft. The Coeur mill was restarted in September 2007 to process silver/lead ore from the Galena mine. By early 2008, silver/lead ore was trammed from the Galena mine 3700 Level to the Coeur shaft (Coeur 3400 Level) and was hoisted up the Coeur shaft for processing at the Coeur mill. During 2012, the Coeur Mine was rehabilitated for mining, which started in September 2012. However, underground work ceased in 2014.
Primary Metals/Minerals
Silver.
Secondary Metals/Minerals
Copper, lead and zinc.
Geology/Mineralisation
The Galena Complex is hosted by metamorphosed Precambrian sedimentary rocks, which are part of the Belt Supergroup. The strata comprise primarily fine-grained quartz and clay, which has metamorphosed into fine-grained white mica or sericite.
Three major rock types are recognised – vitreous quartzite, siltite argillite, and sericitic quartzite.
Mineralisation at the Galena Complex occurs in steeply dipping fissure filling veins, and in wide disseminated zones, all occurring near four major fracture systems and three major faults. The veins largely strike east–west and north-east to south-west, and range in thickness from a few centimetres to more than 5 m. The vein mineralisation is of two distinct types – silver/copper mineralisation containing tetrahedrite and lesser chalcopyrite as the principal economic minerals; and silver/lead mineralisation dominated by argentiferous galena. Gangues in both types are predominantly siderite, with varying amounts of pyrite and quartz.
The silver/lead mineralisation occurs as well-defined, steeply dipping, relatively narrow veins, and as wider zones of disseminated and stringer mineralisation. The latter type occurs predominately in the eastern part of the property, in the Caladay zone, on and adjacent to the former Caladay property.
Reserves
Total proven and probable silver reserves as at June 30, 2021, were estimated at 652 000 t grading 475 g/t. Lead reserves were estimated at 418 000 t grading 6.33%. Copper reserves were estimated at 234 000 t grading 0.71%.
Resources
Total measured and indicated resources as at June 30, 2021, were estimated at 2.95-million tonnes grading 407 g/t silver and 7.8% lead. Copper resources were estimated at 851 000 t grading 0.59%.
Inferred silver resources as at June 30, 2021, were estimated at 4.42-million grading 450 g/t. Lead resources were estimated at 3.37-million tonnes grading 8.15% and copper resources were estimated at 1.05-million tonnes grading 0.63%.
Mining Method
Cut-and-fill, and mechanised cut-and-fill.
Major Infrastructure/Equipment
The property hosts three active shafts and two process facilities – the 630 t/d Galena mill, which currently produces a silver/lead concentrate, and the 450 t/d Coeur mill, which is on care and maintenance.
Surface facilities include compressor houses, mine dry, mine and administrative offices, warehouses, timber framing yard, parking areas, hoist houses and headframes, a core storage facility, electrical power lines and substations, as well as a modern telecommunications system.
Prospects
Substantial resources exist outside of the Galena Complex’s defined reserve, and exploration continues to develop resources and identify new areas of mineralisation.
Contact Details
Americas Gold and Silver
Tel +1 416 848 9503
Email info@americas-gold.com
Website https://www.americas-gold.com
Sources
Americas Gold and Silver. Annual information form for the financial year ended December 31, 2021 (March 28, 2022).
Americas Gold and Silver. Website https://www.americas-gold.com [accessed May 2022].