Open-pit mining - WikipediaOpen-pit, open-cast or open cut mining is a surface mining technique of extracting rock or . Open-pit mines are used when deposits of commercially useful minerals or rocks are found near the surface; that is, where the overburden . Heavy machinery extracting lignite from Garzweiler surface mine in Germany during 2008.surface mining machine used open cast,Surface mining - WikipediaSurface mining, including strip mining, open-pit mining and mountaintop removal mining, is a . In most forms of surface mining, heavy equipment, such as earthmovers, first remove the overburden. Next . The more common method is "area stripping", which is used on fairly flat terrain, to extract deposits over a large area.
surface mining machine used open cast