The Lucky Friday silver, lead and zinc mine is located deep in the Bitterroot Mountains, in one of the world’s most prolific silver-producing districts: northern Idaho’s Silver Valley.
Lucky Friday has been in commercial production since 1942 and this week the number 4 shaft project to extend the life of the mine for another generation reached a big milestone. Cementation USA Inc. on Tuesday announced it has completed sinking the deepest shaft in the United States at the mine owned by Hecla Mining outside the town of Mullan in Shoshone county, Idaho.
With a finished diameter of 18 feet, the Lucky Friday #4 Shaft was sunk to a final depth of 9,587 feet (2.92 kilometres) below surface. The project is moving into the furnishing construction phase where shaft steel and the final conveyances will be installed.
Hecla, which is celebrating its 125th year of operations, kicked off the expansion project at a cost of roughly $225 million as far back as late 2008 and completion is scheduled for late 2016.
The Cementation group, which is currently sinking 15 shafts worldwide, has sunk the deepest single lift shaft in the world at South Deep Mine in South Africa, the deepest shaft in Canada at Kidd Mine D No.4 Shaft, the deepest single lift shaft in the United States at the Resolution Copper Project, and now the deepest shaft in the United States.
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