Special mining techniques must be used in the complicated strata of this crater.

Gold was first discovered in 1872, followed by exploitation of the deposits using hydraulic mining techniques.

By the 19th century the lead mines were well developed and concerns arose necessitating mining techniques.

He was one of the leaders who brought westernized mining techniques to the city.

Thanks to the sophistication of modern mining techniques, little damage would have been caused to most other properties.

The use of a mining technique such as the one described here will be most valuable in this context.

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

Gain insight into traditional mining techniques on a visit to a sapphire mine.

On a small scale, Lu was using the standard open-pit mining technique.

To make matters worse, better mining techniques threaten to expand the gold supply.