Name: Macassa mine.       

Location: The project is located in Kirkland Lake, Ontario, Canada.

Controlling Company: Kirkland Lake Gold.

Brief Description: The Macassa mine is on one of the highest gold grade mines in the world. The property comprises 253 mining claims in the Teck and Lebel Townships that covers 4 035 ha.

Brief History: The Macassa mine started operation in 1933 and has since had numerous owners. Operations were suspended in 1999, owing to depressed gold prices and the mine was allowed to flood in 2000. Underground mining restarted in 2002.

Products: Gold.

Geology/Mineralisation: The gold mineralisation at Macassa is found along breaks or faults, in veins as quartz-filled fractures, breccias and sulphide-rich (pyrite) zones. There are multiple mineralised breaks – ‘04, ‘05, No 6, Kirkland Lake Main and the Kirkland Lake North and South branches. The breaks strike north to east and dip south in keeping with the Timiskaming trend. The trend of the gold mineralisation in the Kirkland Lake camp conforms to the westerly plunge of the syenite intrusives.

The South mine complex (SMC) was a significant discovery, with the zone having a different character than the zones historically mined at Macassa. The SMC is associated with a cross-over structure, which links the ’04 /Main break with the Amalgamated break. The mineralisation trends parallel to the main structures, but has a much flatter dip ranging from 20° to 50° south. SMC mineralisation has been found to have greater widths and contain higher grades than the main zones. Considerable potential exists for future exploration drilling to identify additional parallel and stacked zones located above, below and along strike of the known SMC zone.

Reserves: Total proven and probable reserves as at December 31, 2017, were estimated at 3.01-million tonnes grading 21 g/t gold.

Resources: Total measured and indicated resources as at December 31, 2018, were estimated at 3.8-million tonnes grading 17.1 g/t gold. Inferred resources were estimated at 1.92-million tonnes grading 22.2 g/t gold.

Mining Method: The main mining methods includes long-hole stoping, mechanised overhand cut-and-fill, and underhand cut-and-fill.

Major Infrastructure and Equipment: Access to the mining areas is through No 3 Shaft, which has an average capacity of 2 200 t/d.

After crushing and grinding, the ore is processed by conventional cyanide leaching using a carbon-in-pulp recovery system. The mill capacity is 2 000 t/d and average recovery is about 97%.

Prospects: The discovery of the SMC has enabled the Macassa mine to increase its level of production significantly over the past few years. The SMC has been driving grade improvement at Macassa, with results from ongoing exploration drilling continuing to extend the SMC mineralisation and adding to the mine's mineral resources in support of growing production and extending mine life.

On January 17, 2018, Kirkland announced plans to sink a new shaft at Macassa. The new, 6.5-m-diameter, concrete-lined shaft will offer several important benefits to the mine, including derisking the operation, allowing for more effective underground exploration to the east of the SMC, improving ventilation and general working conditions in the mine, and supporting higher levels of production and lower unit costs. The new four-compartment shaft will have a total hoisting capacity of 4 000 t/d (ore and waste) and is an important component of the company’s plan to increase production at Macassa to reach more than 400 000 oz/y over the next five to seven years.

Construction of the shaft will be completed in two phases. Completion of Phase 1 is targeted for the second quarter of 2022 and Phase 2 for the end of 2023.

Contact Details:
Centerra Gold
Tel +1 416 840 7884
Email info@klgold.com