Coeur Alaska - Kensington Mine
The Kensington underground gold mine and associated milling facilities are located within the Berners Bay Mining District on the east side of the Lynn Canal about 45 miles north-northwest of Juneau, Alaska. The project is wholly owned and operated by Coeur Alaska, Inc., a wholly owned subsidiary of the Company.
The Kensington mine commenced commercial production on July 3, 2010. The mine is accessed by a horizontal tunnel and utilizes conventional and mechanized underground mining methods. Ore is processed in a flotation mill that produces a concentrate which is sold to third party smelters. Waste material is deposited in an impoundment facility on the property or combined with cement and used as backfill in the mine. Power is supplied to the site by on-site diesel generators. Access to the project is either by air or boat.
Kensington resumed full production ahead of schedule in April 2012 following a temporary reduction in mining and milling activities to allow for the completion of several underground and surface improvement projects. The underground paste backfill plant is in operation, the mine's electrical infrastructure was upgraded, and new surface facilities - including a new administrative building, warehouse, worker dormitory, and expanded kitchen and dining facilities - are completed. Underground development continues to advance.
Geology and Exploration Potential
The Kensington ore deposit consists of multiple, gold-bearing mesothermal, quartz, carbonate and pyrite veins and discrete quartz-pyrite veins hosted in Cretaceous-aged Jualin diorite. Gold occurs as native grains in quartz veins and is associated with pyrite and various gold-telluride-minerals associated with the pyrite mineralization.
The mine area consists of two contiguous properties, Kensington and Jualin, which constitute the majority of the Berners Bay Mining District. The Kensington property includes the Kensington and Raven mineral deposits, which contain all the mineral resources and reserves currently defined, as well as other gold occurrences such as Eureka and Elmira. The adjacent Jualin property includes the Jualin, Comet, Kimberly and other mineral occurrences. Both Kensington and Jualin properties are held through a combination of state and federal patented and unpatented lode mining claims either owned directly or under lease. All of the defined mineral resources and reserves are contained in the Kensington block.
The Company spent $4.1 million on exploration at Kensington in 2012, completing 60,666 feet (20,137 meters) of core drilling during the year and plans to spend $9.4 million on exploration in 2013.
Much of the exploration work in 2012 was devoted to in-fill drilling of Block K and the Raven deposit, a gold-bearing quartz vein system due west of the main Kensington deposit and mine, and several other targets. Ongoing exploration is focused on defining and expanding the current mineral resources and reserves at Kensington.
2013 production at Kensington is expected to be 108,000 to 114,000 ounces of gold. Kensington's proven and probable reserves were 1.0 million contained ounces of gold at year-end 2012. Additional measured and indicated resources totaled 526,000 contained ounces of gold, and inferred resources of 172,000 ounces of gold.