The HM claim is part of the Macassa mine complex located in Kirkland Lake, Ontario. The KirklandLake mining camp has been a prolific gold producer since mining began there in 1915. Gold mineralization at Macassa is found along breaks or faults, in veins as quartz filled fractures, as sulphide rich pyrite zones and as breccias.
The HM claim is an area that hosts the easterly extension of the South Mine Complex (SMC) and is located southeast of the #2 shaft at the Macassa mine. The exploration results from the SMC and HM Claim have identified a significant new find as some of the veins have larger widths and higher grades than the Macassa main zones. Development of a new shaft to support higher levels of production and to enable more effective underground exploration east of the SMC was completed in early 2023.
Mining at Macassa is conducted primarily with overhand and underhand cut-and-fill methods. The Macassa mill was constructed in 1986, originally designed for throughput of 725 tpd but has been upgraded to handle 2,000 tpd. Ore processing at Macassa starts with crushing and grinding before it enters leach tanks for cyanidation and then flows through a carbon-in-pulp circuit, followed by a Merrill-Crow recovery system. The concentrate is melted in a furnace where doré is poured that typically contains 85% to 88% gold.
