In the inferred category, there are 35,000 tonnes grading 0.65 g/t gold suitable for open pit mining (0.65 g/t cut-off) and 375,000 tonnes at 4.33 g/t gold for underground recovery (1.75 g/t cut-off). The total inferred resource is 410,000 tonnes averaging 4.12 g/t gold for 55,000 contained ounces.
The previous resource estimate was made in 2016 when a cut-off of 5 g/t gold was applied. This year’s update with the lower cut-offs resulted in lower estimated grades in both the indicated and inferred categories. However, the 2021 updated increased the estimated tonnages by 186% in the inferred portion and 593.4% in the indicated portion. The estimated in situ gold ounces also rose – 23.9% in the inferred portion and 290.1% in the indicated category.
The resources estimated in the Greywacke North deposit will be added to the updated numbers for the North Lake deposit, an estimate for which is currently being compiled. When the North Lake resource estimate was made in 2020 using a cut-off grade of 0.4 g/t, it contained 14.1 inferred tonnes grading 0.92 g/t gold for 417,000 contained ounces.
MAS has plans to build a centralized mill to treat North Lake ore blended with higher grade material from the company’s other La Ronge gold belt deposits.
(This article first appeared in the Canadian Mining Journal)
