What is open cast mining? | ReferenceOpen cast mining is a type of surface mining in which mineral resources are removed . used for coal extraction are surface mining and underground mining.open cast mining and underground mining,Open-pit mining - WikipediaOpen-pit, open-cast or open cut mining is a surface mining technique of extracting rock or . the overburden is thick or the mineral occurs as veins in hard rock—underground mining methods are used to extract the valued material.
open cast mining and underground mining