Both the Eagle River and Mishi deposits are mesothermal lode gold deposits hosted by Archean Greenstone Belts.

The Eagle River deposit has been described as a vein type deposit along a regional deformation zone with discrete brittle-ductile shears localized along lithological contacts (Heather 1986 and 1991).

Gold bearing quartz veins at Eagle River are hosted primarily by subvertical to steeply north dipping east-west striking shear zones within an elliptical quartz diorite stock with dimensions of 2.0 kilometres east-west and 0.5 kilometres north- south.

The quartz diorite stock intrudes a steeply dipping north-facing sequence of thin mafic to intermediate volcanic flows, flow breccias and interflow volcaniclastic rocks.

A number of different ore zones have been distinguished that constitute different segments of the overall shear zone corridor and each has its own gold grade characteristic. Mineable portions of the individual zones form ore shoots that plunge steeply to the east. The bulk of the historic production has come from Zone 8 and Zone 6, which are entirely within the intrusive quartz diorite, while Zone 2 mineralization is hosted in sheared mafic volcanic rocks just east of the stock.

In general, the ore shoots mined to date occur at a spacing of 400 metres along a 2.4 kilometre strikelength. They appear to be spatially related to an array of oblique 110º striking mafic dykes, which pre-date mineralization and deflect into and out of the shear zones.

Gold mineralization is structurally concentrated within highly strained portions of the various quartz veins. Ore microscopy (Clemson, 1989; Johnston, 1990) indicates that 60% of the gold occurs along quartz-sericite grain contacts, 32% along sulphide-gangue contacts and 1.4% within sulphide grains. The grains are generally less than 500 microns, free milling and 40 to 60% recoverable by gravity methods. Gold grains less than 5 microns account for a negligible percent of the total gold. Free gold generally occurs as a multitude of fine grains which result in a relatively low sub sampling variance generating very good assay precision for a vein type gold deposit.

The Eagle River Mine has been in continuous commercial production since January 1, 1996. In its early years, he deposit was mined using shrinkage methods before converting to its current mining method of longhole stoping with a typical sub-level interval of 15 m between levels. The Company successfully tested the alimak mining method in the 990-303 zone in 2020. The alimak mining method utilizes access the ore body via an alimak raise and to subsequently drill and install deep support in the hanging wall of the stope and then drill and blast ore material from bottom-up. The alimak mining method has been proven to accelerate the stop ycle and to reduce mine dilution. Two stopes are planned to be mined using the alimak method in 2021.

Presently, about 30% to 50% of gold production comes from sub-level/development ore with the balance from longhole stoping. Minimum mining width is 1.5 m with sublevels being typically 15 m apart vertically. Fan double cable bolt holes are grouted in both the hanging wall and footwall to reduce overbreak and control dilution.

Longhole mining was adopted as the primary mining method at Eagle River Mine in year 2001. The method generally uses downholes or upholes depending on ore configuration and mine design. The blasthole diameter is 2.5 inches. Downholes are generally drilled at 90° and upholes drilled at a dip of 70° to minimize the possibility of loose material striking employees or equipment and to ensure the blastholes break to the ends thereby keeping the stope height at a maximum. Hole lengths are generally limited to 13 m; however, hole lengths of 15 m are common.

Mining recovery is included in the conversion from resource tonnage to reserve tonnage but does not affect grade as the grade of losses is assumed to equal the resource average. The mining recovery for bulk methods is typically 90 percent. Besides ramp access to underground workings, the Eagle River Mine has a three-compartment shaft and currently operates with a Canadian Ingersoll-Rand 2.4m (8-foot) diameter double drum, double clutch hoist driven by two DC motors through a single reduction open gear and pinions. Each motor is rated at 400HP at 400rpm with a maximum hoisting speed of 1194 fpm and a payload of 8800 pounds. Based on 20 operating hours per day, the hoisting capacity is approximately 3,100 tonnes per day from current hoisting depth of 420 m.

There are currently three primary ramp systems at Eagle River Mine: the West Ramp, East Ramp, and the Shaft Ramp. The West Ramp starts at 325 m level and continues to the 590 m-level. The ramp is currently inactive with respect to production activity. Services are available along this ramp and pumping is ongoing.

The East Ramp is the primary ramp for the mining zones in Eagle River Mine. It accesses the primary stoping areas at various take off points: 2 Zone @ the 220 m level, 3 Zone @ 750 m-level, 6 Zone, 7 Zone, 807/808/809/810/811/817 zones at various levels. This ramp currently goes from surface to the deepest level of the mine, which now extends pass the 1062 m level.

The Shaft Ramp starts at approx. 650 m level and continues down to the 779 m level. The Eagle River Mine has four shaft stations below the 70 m: 220 m, 460 m, 520 m, and 580 m levels.

General ramp design is based on the maximum size equipment used in the mine. The cross section is required to be 4 m height by 5 m width. Ramp grades vary from between +15% and -15%. The main ramp reached the 1130 level at the end of 2020.

Wesdome initially leased then subsequently acquired the former Magnacon mill and tailings facilities in 1996. The mill is 17 km by road from the mine. The mill capacity was increased from 600 to 1,000 tpd in 1999. Even though the addition of a cone crusher expanded capacity to the permitted level of 1,200 tpd on a crushing basis, required maintenance time means the practical limit is approximately 850 tpd Eagle River underground ore as it is configured to achieve targeted gold recoveries.

The mill employs the Merrill-Crowe process for the recovery of gold from Eagle River ore with about 40% of the gold recovered into a gravity concentrate using a Falcon gravity circuit concentrator. The Merrill-Crowe process involves cyanide solution and zinc precipitation. Precipitate is refined on site to produce doré bars containing approximately 80%-92% gold. By-product silver is recovered at a rate of one part for every six to ten parts of gold. The doré bars are shipped to the Royal Ca ........