First published by Money Metals here: https://www.moneymetals.com/news/2018/04/06/two-mines-supply-half-of-us-silver-001452

Just two mines supply the United States with half of its silver production, and both are located in Alaska. It’s quite amazing that Alaska now produces half of the silver for the U.S. when only 30 years ago total mine supply from the state was less than 50,000 oz per year. The silver produced in Alaska comes from the Greens Creek and Red Dog Mines. One is a primary silver mine and the other a zinc-lead base metal mine.