number of units of unpayable material (waste rock or overburden) which must be removed to expose one unit of ore in an open pit.

The ratio of the number of tons of waste material removed to the number of tons of ore removed, used in connection with open pit mining.

Ratio of ore rock to waste rock.

The ratio of overburden and segregable waste to ore in an open pit operation.

The ratio of waste tonnes to ore tonnes mined calculated as total tonnes mined less ore tonnes mined divided by ore tonnes mined.

the ratio of the amount of waste rock removed per tonne of ore mined

(4) the ratio of non-ore or non-coal material (lithified or non-lithified) that must be excavated to extract a given amount of ore or coal. A measure of the amount of material that must be excavated in order to remove the coal or ore grade material.

The number of units of unpayable material that must be mined to expose one unit of ore.

The ratio of tonnes removed as waste relative to the number of tonnes or ore removed from an open pit mine.

The ratio of tons removed as waste relative to the number of tons of ore removed from an open pit mine.

The unit amount of overburden that must be removed to gain access to a similar unit amount of coal or mineral material.