The Porcupine mines are situated in the Porcupine Camp in Archean rocks of the western Abitibi Greenstone belt in the Canadian Shield. These consist of ultramafic and mafic volcanic rocks of the Keewatin subgroup overlain by sedimentary rocks of the Timiskaming group. The lands lie adjacent and to the north of the regionally significant Porcupine Destor Fault. Gold mineralization is found in a number of different structural settings and consists of continuous quartz carbonate veins, quartz tourmaline veins, quartz stockworks and gold associated with disseminated sulphides.

Mineralization at Hollinger and Hoyle, in Timmins, comprises multiple generations of quartzcarbonate-tourmaline albite veins, associated pyrite alteration envelopes, and disseminated pyrite mineralization. Mineralization at Borden consists of a shear zone containing quartz-vein hosted sulfides within a high-grade metamorphic greenstone package.

The Hoyle Pond.
The Hoyle Pond Main Zone and 1060 Zone deposits occur on opposite limbs of an open, northeast-plunging antiformal structure, hosted within carbonatized north-dipping tholeiitic basalts. The 7 Vein System occurs as a series of stacked, flat to gently northeast-dipping veins in the nose of the antiformal structure.

The Hoyle Pond Main Zone includes a series of generally northeast-striking, linked, quartz vein zones folded on a small scale with moderate west- and northeast-plunging axes.

The 1060 Zone cons ........

Porcupine, consists of the Hollinger open pit and Hoyle pond underground operations, located in the city of Timmins, Ontario, as well as the Borden underground operation, located near the town of Chapleau, Ontario. Borden mine is the world’s first all-electric underground mine.

Currently, approximately 60% of the gold comes from the Hoyle Pond underground mine, where mechanized cut and fill and longhole mining methods are used to extract the ore, and the remaining ore comes from the Hollinger Open Pit mine. The Dome Underground mine ceased operations in 2017.

Hollinger Open Pit mine
There is sufficient grade at specific gold price-points to mine a 150m deep pit, with the rock being processed at the nearby Dome Mine mill. The voids (sub-vertical stopes, shafts, and connecting drifts/drives) are sometimes spaced nearly 20-50m apart extending several hundred metres deep in a 2km square area beneath the City. The pit design was constrained by a regional highway (and the City’s water tower) along the northern wall, with homes and businesses on all other sides of the Property.

The Hollinger is being mined using three 6m and two 9m cuts making up 18m high benches in mostly FAIR to GOOD ground. All blasting is done with blast-mats to reduce fly-rock and noise. Because the mine is in-town, damage needs to be minimised. Earlier, blast trials were conducted to determine the depth of blast-damage induced by varying sizes of confined blasts. These tri ........

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