A drop in grade as expected in the September quarter meant fewer gold ounces were produced from its Co-O gold mine in the Philippines, said Medusa Mining Ltd (ASX:MML).
The firm produced 21,157 ounces of the yellow metal at an average head grade of 5.26g/t against 25,429 ounces at 6.32g/t in the preceding June quarter.
The drop in grade was expected mostly because of 9% more mine development in the quarter compared to the previous three months.
That saw 4,960 metres of horizontal and vertical mining compared to 4,501 metres in the June quarter.
Production guidance for the full year to June 30, 2017 remains the same, however, at 105,000 to 115,000 ounces, Medusa said.
The miner sold 21,152 ounces in the period, down from 25,519 in the previous three months, while all in sustaining costs (ASIC) were US$1334 per ounce compared to US$1088 in the June period, impacted by exceptional costs like automation at the mill and costs related to dewatering.