Macassa output during March best in 57 years

The Macassa gold mine of LAC Minerals (TSE) near Kirkland Lake, Ont., smashed its previous records by posting a single-month gold output of 12,353 oz. in March. The mine had never before produced more than roughly 9,000 oz. in a single month during its 57-year history. “This month (March) was just fantastic,” said Gerald Gauthier, senior vice-president of operations. “We had days when the head grade was running 0.8-0.9 oz. per ton.” High-grade stopes and a new, made-to-measure mining method contributed to the record output.

The mine came into production in the midst of the Depression in 1933. But as old as it is, annual output has been rising, not declining, since LAC commissioned the No. 3 production shaft in 1986.

The average recovered grade for the month was 0.675 oz. Mill recovery averaged 96.8%. (The figures cited relate to mined ore, not production from Macassa’s Lakeshore tailings project.)

It was also a banner month in terms of mine production, which topped out at 18,311 tons. Last year’s monthly average was 13,790 tons and the average monthly gold yield was 6,878 oz.

LAC has forecasted that mine production should yield 85,000 oz. of gold this year. But with the March bulge, the mine might surpass that target. Gauthier was not prepared to look quite that far ahead. But he did concede that “we’ll have a very nice first quarter.”

Last year, Macassa turned out 82,540 oz. (The Lakeshore tailings project has a budgeted output target this year of another 13,000 oz.)

Macassa is a high-grade, narrow-vein operation and the sole remaining producer on the Kirkland Lake Main Break that, in the region’s heyday, fed the likes of the Lakeshore and Wright-Hargreaves mines.