Marathon Gold Corp. has reported results of a prefeasibility study (PFS) of its Valentine gold project in Central Newfoundland. The study supports an open-pit mining operation, with low initial capital cost of C$272 million and a high rate of return over a 12-year mine life. Gold production would average 175,000 ounces per year (oz/y) in years 1 through 9 from processing high-grade mill feed and 54,000 oz/y in years 10 through 12 from processing a low-grade stockpile.
Mill capacity is planned at 6,800 metric tons per day (mt/d) during years 1 through 3 based on gravity-leaching, expanding to 11,000 mt/d in year 4 based on gravity-flotation-leaching, with life-of-mine average gold recovery of 93%.
Proven and probable mineral reserves total 1.87 million oz of gold in 41.05 million mt at a grade of 1.41 grams (g) per mt. Life-of-mine total cash costs are estimated at US$633/oz, and all-in sustaining costs are estimated at US$739/oz. After-tax payback is estimated at 1.8 years.
Marathon is targeting completion of a feasibility study of the Valentine project in the first half of 2021, completion of the Environmental Assessment and Ministerial Approval by mid-2021, and commencement of site-specific permitting thereafter. Ground-breaking for site construction is scheduled for January 1, 2022, followed by an 18-month construction period and first gold production by mid-2023.
The Valentine project PFS contemplates open-pit mining from the Marathon and Leprechaun deposits only. Ore with a cut-off grade of 0.70 g/mt gold will be prioritized for mill processing, initially at 6,800 mt/d and then at 11,000 mt/d. Ore between 0.70 g/mt and 0.33 g/mt gold will be stockpiled for processing at the end of the mine life.
Each deposit will be developed in three phases, with the Marathon pit achieving maximum dimensions of 1,250 m by 700 m by 294 m deep and the Leprechaun pit achieving maximum dimensions of 1,050 m by 650 m by 306 m deep. Life-of-mine strip ratios will be 6.7 at Marathon, 9.1 at Leprechaun and 7.6 overall.
Mining will be by conventional drill-blast-load-haul methods on 6-m bench heights with 8-m-wide berms every third bench. Dual-lane haul road allowances will support a diesel-powered mining fleet that will include 32 90-mt-payload trucks operating between the two open pits.
