ABSTRACT
706Waste rock, also known as spoil or mullock, is produced in most mining operations as a necessary consequence of accessing an ore body. Various terms are used for the waste rock, depending on its distribution in relation to the ore. For example, the term overburden is used for waste material overlying an ore body. Similarly in a stratified situation such as a sedimentary sequence involving multiple seams of coal, the waste rock between coal seams is known as interburden. The ratio of waste rock to ore is known as the stripping ratio. A stripping ratio of 3 means that 3 tonnes of waste is excavated for each tonne of ore.
