VANCOUVER (miningweekly.com) – West Africa-focused gold producer Semafo reported lower gold output for the second quarter ended June, as grade control issues at the Siou satellite deposit of the company's flagship Mana mine, in Burkina Faso, impacted on output.
Montreal, Quebec-based Semafo produced 47 600 oz of gold for the three-month period, down 14% from the 55 400 oz produced in the preceding period, and down 22% year-on-year when compared with the 61 300 oz of gold produced in the comparable period of 2016.
The Mana mine processed 675 500 t at an average grade of 2.31 g/t gold in the quarter, including 194 100 t of low-grade material at an average grade of 0.72 g/t gold. The mine’s falling grade is clear when compared with the 3.33 g/t gold in the same period last year, and 3.71% for the second quarter of 2015.
Semafo advised that, following geological interpretation issues in the upper portion of Zone 9 of the Siou deposit earlier this year, the company has changed its method of grade control from channel sampling to reverse-circulation (RC) drilling.
Subsequently, in-pit RC drilling started at the end of May and is being conducted to a vertical depth of up to 30 m. Semafo expects to be in a position to disclose the grade control results by early August, compared with the mining plan for Zone 9 for the remainder of the year.
“In light of the above, the corporation is confident that Zone 9, which hosts the widest gold-rich structure of Siou's mineral reserves, remains high-grade,” Semafo said in a statement on Thursday.
Semafo reaffirmed its 2017 production guidance of between 190 000 oz and 205 000 oz of gold and its all-in sustaining cost guidance of between $920/oz and $960/oz.