The original JORC-compliant estimate of ore deposits at Prognoz, dated March 1, 2020, includes 7.9 million tons of ore at an average Ag grade of 560 grams per ton, containing 142 million ounces of silver. The reserves were only used for the ore zones of Glavnaya (Main), Boloto (Swamp), and Yuzhnaya (Southern).

Estimates of reserves are based on the silver price of USD15 per ounce, with silver accounting for about 90 percent of the value at this price level.

The mineral resources added to the ore reserves are estimated at 5.6 million tons of mineralized material at an average grade of 552 grams per ton for 100 million ounces of silver.

The preliminary feasibility study assumes nine years of open-pit mining with conventional flotation flowsheet producing clean high-quality concentrate.

The company expects average annual production of 13.5 million ounces of payable silver at all-in sustaining costs to be in the range of USD8 to USD9 per ounce.

Total capital expenditures for the project are expected to be USD319 million, including USD250 million in pre-production costs for capital expenditures (including pre-stripping costs) and USD69 million in maintenance costs for capital expenditures.

“This estimate confirms that Prognoz is one of the world’s best silver development projects,” said Vitaly Nesis, CEO of Polymetal. “We will continue to move the project forward towards development,” the CEO added.

Prognoz is Russia’s largest undeveloped primary silver deposit. The license area is located in the Verkhoyansk district of the Sakha Republic (Yakutia), Russia. The property is located about 980 kilometers from the regional center of Yakutsk (300,000 inhabitants) and 720 kilometers by road from the Nezhda project of Polymetal.

The silver-copper-lead-zinc mineralization, represented by quartz-carbonate-sulfide veins, is in a sequence of sedimentary rocks consisting of Triassic sand and silt. Nine mineralized zones are defined, with the Glavnaya and the Boloto zones being the largest. Mineralized material is partially oxidized, with the depth of weathering strongly dependent on the relief and the proximity of the groundwater. The deposit is situated in a mountainous area with altitudes between 300 and 1,100 meters above sea level. The local topographic relief in the exploration area extends from 300 to 350 meters.

In April 2018, Polymetal consolidated the asset 100 percent. In October 2018, the company completed a JORC-compliant mineral resource estimate of 237 million ounces of silver at 731 grams per ton.