Polymetal upgrades resource estimates at Russia silver mine

Polymetal International on Wednesday upgraded the mineral resource estimate at its Russian Prognoz silver deposit after drilling results “exceeded expectations”.

The fresh estimate amounted to 256m ounces of silver equivalent at 789 grams per tonne Polymetal said.

Polymetal said the average silver grade increased by 25% to 731 grams per tonne and the average vein width increased by 15% to 2.2 metres, despite a 19% fall in contained pure silver to 237m ounces.

“In-fill drilling results exceeded our expectations and strengthened our belief that Prognoz may succeed Dukat as one of the largest primary silver deposits in the world,” said chief executive Vitaly Nesis.

Polymetal said it planned to complete 24.3 km of diamond drilling next year to upgrade the existing inferred resources to indicated category.

“Based on historic experience, the management expects at least 80% conversion rate,” the company said, adding that all drilling will inform a pre-feasibility study due in the first half of 2020.