Abstract: Methods of hydraulic fracturing a rock mass as part of a method of establishing a block cave mine or extending an existing block cave mine includes (a) drilling a plurality of holes downwardly into the rock mass using drill rig equipment positioned on the ground above a proposed or existing block cave mine; and (b) injecting a hydraulic fracturing fluid into the drilled holes from above-ground hydraulic fracturing equipment and inducing fractures in the rock mass. A hydraulic fracturing equipment installation located above-ground drills a plurality of holes downwardly into the rock mass and injects a hydraulic fracturing fluid into the drilled holes and induces fractures in the rock mass. A non-metallic casing for drilled holes is also disclosed.

Abstract: A method of recovering gold and copper from a sulfide ore includes (a) removing valuable fines from a product stream from a comminution circuit, such as a crushing and milling circuit, for run of mine ore and producing a valuable fines concentrate stream and (b) processing the remaining comminution product stream after valuable fines removal and producing a valuable coarse concentrate stream.

Abstract: An assembly (7) for triggering an explosive in a hole (9) to produce an explosive blast in the hole includes (a) an explosion trigger (15, 19) for triggering the explosive in the hole, (b) a detonation unit body (21) that is configured to be located at or proximate an open end of the hole in an initial position of the assembly in the hole and (c) a trigger cord (31) that is connected to the detonation unit body and to the explosion trigger.

Abstract: A block cave has a draw column height of at least 450 m, a caved volume, a single extraction level and noundercut level, a plurality of drawbells extending upwardly from the extraction level to the caved volume, and a plurality of pillars separating the drawbells and supporting the rock mass above the extraction level. Each drawbell has a drawbell height of at least 25 m. Each drawbell has the following profile when viewed from a direction perpendicular to a drawbell drive in the extraction level: a throat section having opposed parallel side walls extending upwardly from the extraction level, a tapered section above the throat section, and an undercut section above the tapered section.

Abstract: A method of recovering gold and copper from a sulfide ore includes (a) removing valuable fines from a product stream from a comminution circuit, such as a crushing and milling circuit, for run of mine ore and producing a valuable fines concentrate stream and (b) processing the remaining comminution product stream after valuable fines removal and producing a valuable coarse concentrate stream.

Abstract: A method of recovering gold from gold-containing sulphide minerals in an ore that has a recovery-oxidation curve in a graph of % recovery of gold versus % oxidation of the minerals that has a slope of less than 1:1 in a higher % oxidation part of the curve, includes operating at least one oxidation unit to achieve a target % oxidation for sulphur in the ore that is in a higher oxidation part of the curve and producing an output having liberated gold as a consequence of sulphur oxidation in the oxidation unit and allowing variations of the % oxidation in the oxidation unit during the method.

Abstract: A method of recovering gold and copper from a sulfide ore includes (a) removing valuable fines from a product stream from a comminution circuit, such as a crushing and milling circuit, for run of mine ore and producing a valuable fines concentrate stream and (b) processing the remaining comminution product stream after valuable fines removal and producing a valuable coarse concentrate stream.

Abstract: A block cave has a draw column height of at least 450 meters, a caved volume, a single extraction level and no undercut level, a plurality of drawbells extending upwardly from the extraction level to the caved volume, and a plurality of pillars separating the drawbells and supporting the rock mass above the extraction level. Each drawbell has a drawbell height of at least 25 meters. Each drawbell has the following profile when viewed from a direction perpendicular to a drawbell drive in the extraction level: a throat section having opposed parallel side walls extending upwardly from the extraction level, a tapered section above the throat section, and an undercut section above the tapered section.

Abstract: A block cave has a draw column height of at least 450 meters, a caved volume, a single extraction level and no undercut level, a plurality of drawbells extending upwardly from the extraction level to the caved volume, and a plurality of pillars separating the drawbells and supporting the rock mass above the extraction level. Each drawbell has a drawbell height of at least 25 meters. Each drawbell has the following profile when viewed from a direction perpendicular to a drawbell drive in the extraction level: a throat section having opposed parallel side walls extending upwardly from the extraction level, a tapered section above the throat section, and an undercut section above the tapered section.