Open cast -----Open cast = Open pit.Literally, you dig a bigpit from the surface, downwards, and extract rock that contains the mineral you are chasing. If you google “open cast mining” in Google Image you will SEE lots of big holes in the ground.

shaft mining --Actually this isn’t a MECHANICAL Engineering QUESTION, it is Mining Engineering. However, the answer is that there are two major types of mines.A pit mine, also calledan strip mine is whereyou remove the trees, plants and TOPSOIL and dig out the ore or coal from the surface. The deepest open pit mine is in theUSA and is 3900 feet deep. It is a copper mine.A shaft mine, also called a deep mine is where you dig holes (shafts) into the ground with branchesoff the shaft (DRIFTS) to reach the coal or ore. The deepest shaft mine is 12,600 feet deep. It is a diamond mine in South Africa. A drift mine is a variation on a shaft mine where horizontal shafts are excavated into the side of an outcrop of coal or ore.

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but actually open pit and shaft mining is not suitable for comparing ...