The Mining Process – Waihi Gold
The Mining Process. 1. Mining – open pit and underground. To define the ore from the waste rock, samples are taken and assayed. Assay results are used to mark out areas of ore and waste rock, which are mined separately. Some of the harder areas require blasting to loosen the rock prior to excavation by hydraulic diggers. Dump trucks haul the rock to the primary crushers in the open pit or to ...