Hydraulic hoisting of potash and other evaporite ores

A method of hoisting mineral from an underground mine comprising the steps of:

• mining an ore deposit using a mechanical cutting machine to generate a Run-of-Mine (ROM) material at a mine face;
• conveying the generated ROM material to an underground dry ore screening plant;
• at the underground dry ore screening plant, splitting the ROM material into a first stream and a second stream relative to a threshold size wherein the threshold size determines the maximum size of the ROM material to be hydraulically hoisted;
• mixing the first stream of fines material, comprising the ROM material that is below the threshold size, with a saturated brine to create a slurry mixture, wherein the saturated brine is formulated to prevent the fines material from dissolving into the slurry mixture;
• positive displacement pumping to drive, vertically and under high pressure, the slurry mixture to a surface location via a mine exit selected from one of:
• a shaft;
• and at least one borehole, to a surface product separation plant;
• and conveying the second stream of coarse material, comprising the ROM material that is not below the threshold size, to a circuit for vertical skip hoisting, the circuit having a capacity that is available to the coarse material, wherein the coarse material is kept dry to facilitate conveyance, transfer and vertical skip hoisting;
• and wherein the pumping and the skip hoisting is performed substantially simultaneously in parallel to increase a mine hoisting output rate.