Underground mining methods (soft rock and hard rock)

Underground soft rock mining refers to a group of underground mining techniques used to extract coal, oil shale and other minerals or geological materials from sedimentary ("soft") rocks

Underground mining methods for soft rock

• Long Wall Methods

• Room and Pillar Methods

• Short Wall Methods

• Blast Mining Methods

Underground hard rock mining refers to various underground mining techniques used to excavate hard minerals such as those containing metals like gold, copper, zinc, nickel and lead or gems such as diamonds.

Underground mining methods for hard rock, consist of :

• Cut and Fill Methods

• Drift and Fill Methods

• Block Caving Methods

source : http://www.wikipedia.org/