In 1887, they employed 1,100 miners, and they continued to operate until 1899.

Only the alluvial deposits are being worked employing 15,000 miners around the Lake.

The principal business was a coal mine that employed ten miners.

At their height about 100 mines employed 1000 miners.

As of 2008, the company employs 73 miners, all former workers in the closed local mines, and expects their number to reach 150.

Only 57 functioning pits now remain, employing 50,000 miners.

At its peak, Eu's businesses owned a total of 11 mines and employed 12,000 miners.

In December 1984 the mine employed 326 miners, and 290 of those were working underground on three shifts-a-day, five days a week.

The plant used room-and-pillar mining techniques, and employed 170 miners.

United Mine produced only about 36,000 tons of coal and employed 108 miners in its last year of operation.