Overview
Status | Inactive / Suspended |
Mine Type | Underground |
Commodities |
|
Mining Method |
- Cut & Fill
- Longhole stoping
|
Processing |
- Gravity separation
- Flotation
|
Mine Life | 11 years (as of Jan 1, 2014) |
Source:
The Tulsequah Chief mine in northwestern B.C. looks set to languish for years to come, after its owner — Toronto-based Chieftain Metals Corp. — collapsed under a $27 million debt.
It's the second company in less than a decade to attempt to revive the historic mine, and fail.
Summary:
The Tulsequah Chief and Big Bull deposits are polymetallic volcanogenic massive sulphide (VMS) deposits of bimodal-felsic, island arc or arc related affinity, similar to the Kuroko type deposits found in Japan. These deposits are generally associated with back-arc basins associated with subduction tectonic environments. The deposit consists of several distinct lenses of massive sulphide mineralization that were deposited at or slightly below the sea floor due to precipitation from the venting of metal-rich hydrothermal fluids. These fluids typically exploit fault planes as fluid pathways and create a large zone of hydrothermal alteration in the rocks below the deposits. VMS deposits are characterized by concordant massive to banded sulphide lenses, typically occurring within a distinct stratigraphic interval.
Mining Methods
- Cut & Fill
- Longhole stoping
Summary:
The Tulsequah deposit will be accessed via the 120 m (former 5400 level) and 60 m (5200 level) portals. An additional portal will be driven at approximately 84 m level that will act as the SAG mill feed conveyor drift from the mine. The existing 5200 and 5400 levels will be slashed to 5.0 m x 5.0 m to accommodate the trackless equipment fleet. The main mine access will be via the 60 m level and connect to the main ramp that will access the mining levels. The main ramp is 5.0 m x 5.0 m in section and inclined to 17%. The main ramp will access sublevels 30 m apart vertically.
The deposit generally dips at greater than 60° and is variable in thickness from less than 3 m to over 25 m. Several mining blocks are planned to be opened simultaneously throughout the vertical extent of the deposit to give mining flexibility needed for sequencing and early access to higher-grade material. The deposit is favourable to a mix of mining methods with the majority coming from longhole stoping and uppers retreat with minor contributions from cut and fill.
Processing
- Gravity separation
- Flotation
Source:
Summary:
The concentrator design includes standard crushing and grinding unit operations, gravity gold recovery and conventional froth flotation to recover mineral concentrates of chalcopyrite/tennantite (copper iron sulphide), sphalerite (zinc iron sulphide) and galena (lead sulphide) from the ground ore.
The concentrates will be transported to designated smelters worldwide for subsequent reduction into copper, zinc, and lead metal. Average mill throughput is planned to be approximately 1,100 dry tonnes per operating day (1,219 dry tonnes per day at 90% utilization). Total annual concentrate production is planned to be approximately 72,000 dry tonnes.
The primary jaw crusher is planned to be located underground which also houses the jaw crusher discharge feeder and related ancillary systems, as well as the drive system for the conveyor belt that transfers crushed ore to the storage bin. The conveyors and mill building are planned to be completely enclosed.
Th ........

Recoveries & Grades:
Commodity | Parameter | Avg. LOM |
Copper
|
Recovery Rate, %
| ......  |
Copper
|
Head Grade, %
| 1.46 |
Copper
|
Concentrate Grade, %
| ......  |
Lead
|
Recovery Rate, %
| ......  |
Lead
|
Head Grade, %
| 1.29 |
Lead
|
Concentrate Grade, %
| ......  |
Zinc
|
Recovery Rate, %
| ......  |
Zinc
|
Head Grade, %
| 6.95 |
Zinc
|
Concentrate Grade, %
| ......  |
Gold
|
Head Grade, g/t
| 2.85 |
Silver
|
Head Grade, g/t
| 103.72 |
- Subscription is required.
Reserves at December 31, 2014:
Category | Tonnage | Commodity | Grade |
Proven
|
684,000 t
|
Copper
|
1.48 %
|
Proven
|
684,000 t
|
Lead
|
1.36 %
|
Proven
|
684,000 t
|
Zinc
|
7.84 %
|
Proven
|
684,000 t
|
Gold
|
2.71 g/t
|
Proven
|
684,000 t
|
Silver
|
100.59 g/t
|
Proven
|
684,000 t
|
Zinc Equivalent
|
29.4 %
|
Probable
|
3,752,000 t
|
Copper
|
1.45 %
|
Probable
|
3,752,000 t
|
Lead
|
1.28 %
|
Probable
|
3,752,000 t
|
Zinc
|
6.78 %
|
Probable
|
3,752,000 t
|
Gold
|
2.88 g/t
|
Probable
|
3,752,000 t
|
Silver
|
104.39 g/t
|
Probable
|
3,752,000 t
|
Zinc Equivalent
|
28.9 %
|
Proven & Probable
|
4,436,000 t
|
Copper
|
1.46 %
|
Proven & Probable
|
4,436,000 t
|
Lead
|
1.29 %
|
Proven & Probable
|
4,436,000 t
|
Zinc
|
6.95 %
|
Proven & Probable
|
4,436,000 t
|
Gold
|
2.85 g/t
|
Proven & Probable
|
4,436,000 t
|
Silver
|
103.72 g/t
|
Proven & Probable
|
4,436,000 t
|
Zinc Equivalent
|
29 %
|
Measured
|
0.787 Mt
|
Copper
|
1.57 %
|
Measured
|
0.787 Mt
|
Lead
|
1.5 %
|
Measured
|
0.787 Mt
|
Zinc
|
8.6 %
|
Measured
|
0.787 Mt
|
Gold
|
2.81 g/t
|
Measured
|
0.787 Mt
|
Silver
|
105.5 g/t
|
Measured
|
0.787 Mt
|
Zinc Equivalent
|
30.9 %
|
Indicated
|
5.136 Mt
|
Copper
|
1.43 %
|
Indicated
|
5.136 Mt
|
Lead
|
1.28 %
|
Indicated
|
5.136 Mt
|
Zinc
|
6.76 %
|
Indicated
|
5.136 Mt
|
Gold
|
2.8 g/t
|
Indicated
|
5.136 Mt
|
Silver
|
102.1 g/t
|
Indicated
|
5.136 Mt
|
Zinc Equivalent
|
28.1 %
|
Measured & Indicated
|
5.923 Mt
|
Copper
|
1.45 %
|
Measured & Indicated
|
5.923 Mt
|
Lead
|
1.31 %
|
Measured & Indicated
|
5.923 Mt
|
Zinc
|
7 %
|
Measured & Indicated
|
5.923 Mt
|
Gold
|
2.8 g/t
|
Measured & Indicated
|
5.923 Mt
|
Silver
|
102.5 g/t
|
Measured & Indicated
|
5.923 Mt
|
Zinc Equivalent
|
28.5 %
|
Inferred
|
0.439 Mt
|
Copper
|
0.79 %
|
Inferred
|
0.439 Mt
|
Lead
|
1.03 %
|
Inferred
|
0.439 Mt
|
Zinc
|
5.54 %
|
Inferred
|
0.439 Mt
|
Gold
|
2.33 g/t
|
Inferred
|
0.439 Mt
|
Silver
|
80.6 g/t
|
Inferred
|
0.439 Mt
|
Zinc Equivalent
|
21.6 %
|
- Subscription is required.
Corporate Filings & Presentations:
- Subscription is required.
- Subscription is required.