Deposit Type
The Gibraltar open pit mine is a calc-alkalic porphyry copper-molybdenum deposit entirely hosted by the Late Triassic Granite Mountain batholith. This pluton occurs in a fault-bounded panel of Quesnel terrane rocks that are partially enveloped by rocks of the oceanic Cache Creek terrane (van Straaten et al., 2020). The oceanic Cache Creek terrane that occurs to the west and the Quesnel volcanic arc terrane are part of the accretionsubduction complex that was responsible for generating the Granite Mountain batholith and other Late Triassic plutons such as the Guichon Creek batholith that hosts the Highland Valley porphyry Cu-Mo deposits located 250 km to the south-southeast.

Mineralization in the Pollyanna, Granite, and Connector deposits is hosted in massive to strongly foliated zones. In contrast, mineralization in the Extension deposit is almost entirely hosted in strongly foliated shear zones. At Gibraltar mine, the Granite, Pollyanna and Connector deposits have been described as “porphyry-type ore”, the Extension deposit as “shear zone ore,” and Gibraltar as intermediate between the two (Bysouth et al., 1995).

Mineralization
Primary hypogene copper mineralization in the form of disseminated and vein-hosted chalcopyrite predominates at Gibraltar. Minor bornite occurs typically in the east and northeast portions of the deposit. Molybdenite occurs mainly in quartz veins and fractures, and rarely as matrix disseminations. Sphalerit ........

The Gibraltar deposits have been developed using open pit, truck and shovel mining methods since 1971. To date, mining has progressed in several phases in the Gibraltar, Pollyanna, and Granite pits with future mining to continue in the Pollyanna and Gibraltar pits as well as the currently undeveloped Connector and Extension pit areas.

Mining operations supply 85,000 tons per day of ore at an average head-grade of 0.25% copper to two primary crushers which in-turn feed the two concentrators as discussed in Section 17. During the 23-year mine life, a total of 699 million tons of sulphide ore, 17 million tons of oxide ore and 1,667 million tons of waste will be mined from the reserve pits at a strip ratio of 2.4. An additional 6 million tons of stockpiled ore will be processed.

For strategic and operational reasons surplus ore is stockpiled at various times during the mine life and for various amounts of time prior to processing. Waste rock is stored in various waste rock storage facilities next to the pits, as well as in previously mined pits after mining of those pits is complete. Suitable overburden waste is salvaged and stored separately for use in reclamation.

Pit Design
Pit slope designs are based on recommendations from geotechnical consultants and historical operating experience. All the pits in the reserve plan are designed with a bench height of 50 ft, a bench face angle of 65 degrees. Safety berms are a minimum of 27 ft wide and ........

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