Wesdome Gold Mines Ltd.
Mishi Mine
Location and Geology
The Mishi and Magnacon properties consist of a contiguous series of patented claims and mining leases located 50 kilometres due west of Wawa, Ontario and 60 kilometres southeast of Hemlo, Ontario.
The land position covers a 10 kilometre strikelength of a sheared and altered volcano-sedimentary sequence which hosts several known gold occurrences and is situated 15 kilometres north of the Eagle River Mine.
The properties cover a portion of the northern limb of the Mishibishu greenstone belt which is part of the Abitibi Subprovince of the Superior Structural Province of the Canadian Shield. Supracrustal rocks belong to the Mishi Assemblage. This south-facing sequence is dominated by submarine mafic volcanic rocks in contact with epiclastic volcanic and sedimentary rocks to the south.
These rocks strike east-west and dip 40 degrees north. A regional zone of ductile deformation called the Mishibishu Deformation Zone traverses the properties and is localized along the volcanic-sedimentary contact. These Archean supracrustal rocks are crosscut by a series of northeast and northwest trending crossfaults and fractures which are commonly occupied by Proterozoic diabase dykes.
In the Mishi Mine area, the Mishibishu Deformation Zone is sandwiched between a quartz-feldspar porphyry stock to the north and a mafic sill to the south. Mineralization is characterized by disseminated pyrite in ankerite-sericite alteration zones accompanied by 10% irregular smokey quartz vein stringers and lenses. A series of at least eight tabular, en echelon lenses have been identified to date the southernmost of which comes to surface and hosts the bulk of reserves. As the pit is deepened, parallel zones to the north will contribute the bulk of production in the first two years. The lenses plunge northeast at 40 degrees.
Drilling in 2011 traced mineralization both east and west of the 300 metre long pit. The mineralization also remains open at depth. Recent observations suggest the main control on mineralization is the volcanic-sedimentary contact. This contact appears to swing south on the Magnacon property towards the east into a previously unexplored portion of the property.
The Mishi and Magnacon properties consist of a contiguous series of patented claims and mining leases located 50 kilometres due west of Wawa, Ontario and 60 kilometres southeast of Hemlo, Ontario.
The land position covers a 10 kilometre strikelength of a sheared and altered volcano-sedimentary sequence which hosts several known gold occurrences and is situated 15 kilometres north of the Eagle River Mine.
The properties cover a portion of the northern limb of the Mishibishu greenstone belt which is part of the Abitibi Subprovince of the Superior Structural Province of the Canadian Shield. Supracrustal rocks belong to the Mishi Assemblage. This south-facing sequence is dominated by submarine mafic volcanic rocks in contact with epiclastic volcanic and sedimentary rocks to the south.
These rocks strike east-west and dip 40 degrees north. A regional zone of ductile deformation called the Mishibishu Deformation Zone traverses the properties and is localized along the volcanic-sedimentary contact. These Archean supracrustal rocks are crosscut by a series of northeast and northwest trending crossfaults and fractures which are commonly occupied by Proterozoic diabase dykes.
In the Mishi Mine area, the Mishibishu Deformation Zone is sandwiched between a quartz-feldspar porphyry stock to the north and a mafic sill to the south. Mineralization is characterized by disseminated pyrite in ankerite-sericite alteration zones accompanied by 10% irregular smokey quartz vein stringers and lenses. A series of at least eight tabular, en echelon lenses have been identified to date the southernmost of which comes to surface and hosts the bulk of reserves. As the pit is deepened, parallel zones to the north will contribute the bulk of production in the first two years. The lenses plunge northeast at 40 degrees.
Drilling in 2011 traced mineralization both east and west of the 300 metre long pit. The mineralization also remains open at depth. Recent observations suggest the main control on mineralization is the volcanic-sedimentary contact. This contact appears to swing south on the Magnacon property towards the east into a previously unexplored portion of the property.
History
The Mishi gold deposits were discovered by Granges Inc. in the late 1980s. Over $10 million was spent on detailed drilling, stripping, bulk sampling and feasibility studies prior to Wesdome’s purchase of the property in 1998 for $1.4 million.
At the adjoining Magnacon property, Westfield Minerals Ltd. discovered gold in 1984 while drill testing humus geochemical anomalies. In 1985, the Muscocho-Flanagan-McAdam-Windarra joint venture was formed to explore and develop the property. Mining commenced in 1989 and was shut down in October, 1990 after producing about 40,000 ounces of gold from 265,000 tonnes milled.
Wesdome acquired the Magnacon Mill (now Eagle River Mill) in 1996 to treat production from Eagle River, acquired a 75% interest in the property in 2000 and the remaining 25% interest in 2009. In 2004, Wesdome reactivated the project. Underground drilling and rehabilitation work was unsuccessful in validating substantial resources defined by previous owners. As part of this work an 800 metre drift was extended westwards on the 150 metre level. This was established for future exploration of the favourable geology situated between the Magnacon and Mishi deposits.
Mishi’s production history to date is provided below.
Mishi Production
Initially, seasonal open pit mining at Mishi provided an important source of incremental millfeed to replace the Edwards Mine throughput. Additionally, waste rock was used for construction fill in a series of expansion projects at the mill’s tailings management area.
Improving economic conditions prompted a comprehensive re-examination of Mishi’s potential in 2009. A 43-101 Technical Report and Mineral Resource Estimation by independent consultants InnovExplo Inc. was published in August, 2010 (www.sedar.com). Measured and Indicated Resources totalling 5.7 million tonnes at 2.4 gAu/tonne or 438,000 contained ounces and additional Inferred Resources of 1.2 million tonnes at 3.6 gAu/tonne or 140,000 ounces were estimated as a combination of potential open pit and underground accessible material.
This work formed the basis of a 43-101 Preliminary Feasibility study by InnovExplo Inc. dated January 12, 2011 (www.sedar.com). The study recommends mining over a 5-year period 709,431 tonnes of proven and probable reserves at a diluted grade of 2.55 gAu/tonne, representing 58,125 ounces of in-situ gold. This optimization was based on minimizing capital costs and making full use of existing milling capacity and facilities located just 2.0 kilometres east of the pit. Additionally, further engineering studies and drilling were recommended.
Wesdome moved quickly on these recommendations completing engineering and permitting work, broke ground in July, 2011 and announced commercial production January 1, 2012. Stepout and infill drilling completed in 2011 has provided confidence in the continuity of near surface mineralization with good grades both to the east and west of the current 5-year mine plan (Press Releases dated November 22, 2011 and October 11, 2012). A listing of all intersections greater than 1.0 gAu/tonne are tabulated below and are accompanied by a drill hole location plan.
This information will be used to study options for extending existing mine life, assessing the larger resource base and, if merited, supporting capital investment to increase mining and milling rates.
Mishi’s production history to date is provided below.
|
YEAR |
TONNES MILLED |
RECOVERED GRADE |
OUNCES |
|
2002 |
20,000 |
4.41 |
2,838 |
|
2003 |
28,090 |
3.61 |
3,256 |
|
2004 |
43,947 |
3.60 |
5,086 |
|
2007 |
43,458 |
3.14 |
4,382 |
|
2012 |
64,915 |
2.29 |
4,789 |
|
2013 |
22,536 |
3.26 |
2,362 |
|
|
|||
|
Total: |
222,946 |
3.17 |
22,713 |
Going Forward
The Mishi Mine currently supplies incremental millfeed to the Eagle River mining and milling infrastructure. The 5-year mine plan incorporates a small portion of estimated resources. Recent drilling gives us confidence in the potential to significantly extend this mine life. Our goal is to complete mine planning, initiate stripping to confirm continuity, initiate permitting amendments for expansion and incorporate eastern and western extensions of the pit into the mine plan and mineral reserves.
Likewise, an eventual transition to underground mining to produce higher grade incremental millfeed has been considered. Existing underground workings on the 150 metre level provide a potential base for underground exploration, access and development.
On a grander scale, potential exists to examine the merits of a stand alone operation supporting a larger milling complex. This would require significant drilling and capital expenditure. The nature and extent of the mineralization (currently traced over 1.0 kilometre) and typlified by a broad, lower grade halo coupled with the Company’s longterm bullish stance on the gold price and untested neighbouring exploration targets all give us confidence in the longer term potential of these properties.
Source: http://www.wesdome.com/operations/mishi-mine/
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IT Analyst
This position is responsible for supporting end-users primarily at our Eagle River Mine Complex.
Junior Accountant
This position is accountable for supporting accounting processes as well as the processing of accounts payable in a manner consistent with established policies and procedures.
Senior Mine Geologist, Eagle River Mine
• Promote safe work practices and safety culture within a production-oriented environment.
• Maintain drill hole databases and monitor underground diamond drill programs.
• Supervise and participate in the selection of underground diamond drill targets.
Surface Maintenance (Hourly)
Ensure that all buildings, and infrastructures on Wesdome property, as well as roads, culverts, & bridges are properly maintained Work in a safe, environmentally friendly, and cost-effective manner.
Heavy Duty Equipment Mechanic
Heavy Equipment Mechanic is responsible, as part of a team, for maintaining the equipment and mechanical systems of the Eagle River Mine site to ensure smooth and continuous operation.
Maintenance Planner
- Reporting to the Maintenance Projects, Mobile & Mine Fixed Plant Superintendent
- Ensuring compliance with health and safety and environmental regulations and policies is of primary importance with this position.
Hoist Mechanic/Millwright
Reporting to the Eagle River Maintenance Planner or designate, the successful candidate will perform the maintenance and repairs of all surface, underground stationary equipment, long hole buggies, compressors rock breakers and pumps at the mine site.
Manager – Asset Management & Reliability
Reporting to the Mine General Manager, the Manger of Asset Management & Reliability will be an inspirational and innovative leader responsible and accountable for operational performance excellence in the Asset Management and Reliability Department.
Process Plant Maintenance Millwright (RED SEAL CERTIFCATION REQUIRED)
- The Millwright is responsible for doing the maintenance of the milling operation equipment.
- Reports to Lead hand Millwright and Mill General Foreman
Chief Mine Geologist, Eagle River Mine
The Chief Mine Geologist will be responsible and accountable for all work conducted by the Geology Department while ensuring the work is safe, cost effective and makes the most efficient use of manpower and materials.