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Canada

Eagle River Complex

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Overview

Mine TypeUnderground
StatusActive
Commodities
  • Gold
Mining Method
  • Longhole stoping
  • Alimak
  • Sub-level open stoping (SLOS)
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SnapshotEagle River Gold Mining Complex consists of the Eagle River Mine an underground operating mine with mineral assets, the Mishi Mine an open pit mine presently not in production but with mineral resources, and Eagle River Mill the common processing facilities.
Related AssetsEagle River Mine, Mishi Mine

Owners

SourceSource
CompanyInterestOwnership
Wesdome Gold Mines Ltd. 100 % Indirect

Contractors

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Deposit type

  • Mesothermal
  • Vein / narrow vein

Summary:

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 Mishi deposit is somewhat different. Gold occurs primarily with subordinate, discontinuous quartz veins and lenses. In the Mishi Mine area mineralization is hosted by a series of at least 8 tabular parallel zones consisting of ankerite-sericite ± chlorite alteration zones containing 2-8% fine disseminated and a system of sub conformable, dislocated, smoky grey quartz veinlets and lenses. Veins generally vary from 5-20% of the bulk volume of the zones with individual quartz lenses commonly 5-15 centimetres wide.

The 8 zones recognized to date are labelled from south (footwall) to north (hangingwall) M2, M4, M6, M8, M10, M12, M14 and M16. Zones M2 and M4 are close together and are merged when modelling into a Main Zone. The zones strike 100º, dip north 40º and plunge northeast. In general the zones become more felsic, discrete and vein dominated towards the north. Additionally, they appear to be converging eastward and possibly diverging westward.

Historically, mineralization of the Eagle River Mine has been hosted in the mine diorite; however, the Falcon 7 Zone is hosted in volcanic rocks west of the intrusion. Hence, the discovery and subsequent development of the Falcon 7 Zone is important to the Company as it highlights the prospectivity of the volcanic rocks both to the east and west to host additional gold mineralization beyond the currently existing footprint of the Eagle River Mine. Consequently, near-mine exploration is continuing and is focusing on the adjacent Falcon 300 Zone.

The Falcon 7 Zone was discovered in 2019 and now initial sill development has been completed on the 622 and 635 levels in preparation for mining in Q4 2021.

Reserves

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Mining Methods

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Comminution

Crushers and Mills

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Processing

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Production

CommodityUnits2024202320222021202020192018201720162015
Gold oz  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe91,68871,62558,98047,73750,470
All production numbers are expressed as metal in doré. ^ Guidance / Forecast.

Operational metrics

Metrics202320222021202020192018201720162015
Daily milling capacity  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe1,200 t1,200 t1,200 t1,200 t1,200 t
Tonnes milled  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe168,809 t255,804 t309,841 t309,035 t305,227 t
Daily milling rate  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe462 t619 t850 t844 t836 t
Waste  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe

Production Costs

CommodityUnits2023202220212020201920182017
Cash costs Gold USD
Cash costs (sold) Gold USD  ....  Subscribe  ....  Subscribe  ....  Subscribe 621 / oz **   699 / oz **   845 / oz **  
Total cash costs (sold) Gold USD  ....  Subscribe
All-in sustaining costs (AISC) Gold USD
All-in sustaining costs (sold) Gold USD  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe 975 / oz **   985 / oz **   1,146 / oz **  
** Net of By-Product.

Operating Costs

Currency20232022202120202019201820172016
Total operating costs ($/t milled) CAD 502  436  357  389  424  250  204  184  

Financials

Units2023202220212020201920182017
Sustaining costs M CAD  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe 21.4   17.2   15  
Capital expenditures M CAD  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe 33.5   18.2   15  
Revenue M CAD  ....  Subscribe  ....  Subscribe  ....  Subscribe  ....  Subscribe 164   116   94.9  
Gross profit M CAD  ....  Subscribe  ....  Subscribe  ....  Subscribe
Operating Income M CAD  ....  Subscribe 59.3   52.1   31.5  
Pre-tax Income M CAD  ....  Subscribe  ....  Subscribe  ....  Subscribe
After-tax Income M CAD  ....  Subscribe 40.9   14.9   1.3  
Operating Cash Flow M CAD  ....  Subscribe 71.1   46.3   27.2  

Heavy Mobile Equipment

Fleet data has not been reported.

Personnel

Mine Management

Job TitleNameProfileRef. Date
....................... Subscription required ....................... Subscription required Subscription required Apr 24, 2024
....................... Subscription required ....................... Subscription required Subscription required Apr 24, 2024
....................... Subscription required ....................... Subscription required Subscription required Apr 24, 2024
....................... Subscription required ....................... Subscription required Subscription required Apr 24, 2024
....................... Subscription required ....................... Subscription required Subscription required Apr 24, 2024

EmployeesContractorsTotal WorkforceYear
...... Subscription required ...... Subscription required ...... Subscription required 2022
...... Subscription required ...... Subscription required ...... Subscription required 2021

Aerial view:

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