Coeur Alaska - Kensington Mine
Coeur Alaska, Inc.’s Kensington Mine is an underground, hard rock gold mine located within the Berners Bay Mining District on the east side of the Lynn Canal about 45 miles north-northwest of Juneau, Alaska. The mine, which has a small footprint of approximately 240 acres, is accessed via a 45-mile commute along Lynn Canal offering beautiful views including sightings of humpback whales, orcas, and other marine mammals. The project is owned and operated by Coeur Alaska, Inc., a wholly owned subsidiary of Coeur Mining, Inc.
The Kensington Mine (Kensington) commenced commercial production on July 3, 2010. In 2019, Kensington reached the milestone of over one million ounces of gold produced and celebrated its tenth full year of production the next year on July 3, 2020. 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.
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 (between 145 and 65 million years) 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 by Coeur Alaska. All of the defined mineral resources and reserves are contained in the Kensington block.
The Company spent $8.6 million on exploration at Kensington in 2020, completing 124,300 feet (37,875 meters) of core drilling during the year.
Coeur Alaska is in the process of amending its Plan of Operations to increase tailings and waste rock storage capacity to extend the life of the mine for at least ten years. The proposed mine life in the amendment reflects potential positive exploration results, improved metal prices, and ongoing operational efficiencies. POA 1 was analyzed in a Supplemental Environmental Impact Statement (SEIS) by the U.S. Forest Service (USFS). Project documents and public comments are available for review online on the USFS’ project webpage. POA 1 will allow Coeur Alaska to continue to be a major Southeast employer and provide high paying jobs and economic diversity in our region.