The mine, which produces the popular Yogo sapphires, was dormant for nearly four decades.

A few years ago, Yogold USA entered the arena. The mining company first entered into an exploration agreement, which ended December 31, 2022, and then it transitioned into a lease with an option to purchase.

Its lease and option consist of 1,563 acres of deeded ground, where the company is simultaneously engaged in commercial production and underground development as well as surface exploration, President Jerod Edington confirmed to National Jeweler. 

There are two historic workings in the mine. A British group conducted surface mining on top and eventually sunk a shaft to 250 feet underground. 

A group of Americans, meanwhile, went straight into the side of the mountain and back about 700 feet, essentially hand mining the whole way.

The first two seasons Yogold operated the Yogo Mine—in 2020 and 2021—the company was doing only surface mining with the intent of eventually moving underground.

This season, Yogold opened the Kunisaki Tunnel and portions of the American mine, which run parallel to each other. The company is about 700 feet back in the Kunisaki Tunnel now.

The team is using low profile underground excavators and hauling underground trucks, so right now they are producing about 75-100 tons of underground ore per day and will increase production as demand for its Yogo sapphires dictates.

This year, they installed buildings at the site so they can mine and process all winter.