Overview
| Status | Care and Maintenance |
| Mine Type | Underground |
| Commodities |
|
| Mining Method |
- Longhole stoping
- Transverse stoping
- Longitudinal stoping
- Cemented backfill
|
| Production Start | ...  |
| Mine Life | 4.8 years (as of Jan 1, 2018) |
Perkoa operations remain suspended following the April 16th flooding event that resulted in eight fatalities and the suspension of mining and milling operations. Costs related to the flooding event for Q2 amount to $15.2 million. Operating cost and production guidance at Perkoa remain suspended. |
Source:
p. 31-32
| Company | Interest | Ownership |
|
Government of Burkina Faso
|
10 %
|
Indirect
|
|
Trevali Mining Corp.
|
90 %
|
Indirect
|
Trevali is the indirect owner of 90% of the shares in the capital of Nantou Mining Burkina Faso S.A. (“Nantou Mining”), the entity that owns the Perkoa Mine. The remaining 10% of Nantou Mining is owned by the Government of Burkina Faso, in accordance with the Burkina Faso Mining Law.
Contractors
- Subscription is required.
Summary:
The Perkoa deposit lies in a felsic to intermediary series of volcanic and volcaniclastic rocks, within the Paleoproterozoic Birimian Supergroup of West Africa. The prospective Birimian-aged rocks in Burkina Faso are the same sequences that host major gold deposits in Burkina Faso and in the neighbouring countries of Ghana and Mali. The Birimian Supergroup of West Africa is renowned for their gold mineralization; however, known occurrences of base metals are scarce. The Perkoa deposit represents the only significant zinc-silver massive sulphide mineralization discovered in the Birimian to date and it is also the first zincsilver massive sulphide mineralization discovered in this region. Only zinc is being recovered at the Perkoa Mine.
The Perkoa deposit has been classified as a volcanogenic massive sulphide (“VMS”) deposit. VMS deposits are lenses and sheets of massive sulphide that form from seafloor hydrothermal systems where metal rich fluids precipitate on (exhalative) or near the seafloor (sub-seafloor replacement.). The Perkoa mineralization occurs as a series of stacked, northeast-southwest striking tabular VMS lenses hosted, and separated by, tuffaceous material that has been overturned with an average dip of approximately 70°. The deposit is unusual for its high concentrations of zinc and barium mineralization, and relatively low levels of lead and copper. Mineralization occurs within two continuous VMS lenses, the main Perkoa lens and the Hanging Wall len ........
Mining Methods
- Longhole stoping
- Transverse stoping
- Longitudinal stoping
- Cemented backfill
Summary:
The Perkoa mine is an underground operation, however, a small open pit was mined to reach near surface material during initial start-up to increase plant throughput as the underground mine ramped up production. The pit is now complete. Underground mining with contractors carrying out all aspects of the mining process commenced in February 2013.
The mine is accessed via an 85 m long decline in the box cut prior to entering the portal.
The decline and associated cross cuts are excavated in the competent quartz diorite of the footwall. The 5.3 m wide x 5.5 m high decline is a spiral and the level spacing is set at 30 m. Each level is identical with a footwall drive, sumps, and services cubbies.
A ventilation shaft connects all levels of the mine and acts as an emergency egress via the inking bucket (kibble). A further secondary ventilation ramp egress exists into the completed open pit to allow personnel to escape on foot in an emergency situation. A 35 m crown pillar has been maintained between the open pit and underground production workings.
Longhole stoping is being used as the primary extraction method. There are several variations on this mining method employed such as longitudinal and transverse, with both bottom-up and top-down mining sequences. The exact method chosen is dependent on the orebody geometry. Stopes are backfilled with either cemented rock fill (CRF) or waste.
Longitudinal bottom-up stoping has been u ........
Source:
- subscription is required.
Flow Sheet:
Summary:
- subscription is required.
Production:
| Commodity | Product | Units | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 |
|
Zinc
|
Payable metal
|
M lbs
| ...... ^ | ...... | ...... | ...... | 184 | | |
|
Zinc
|
Concentrate
|
kt
| | | | | 197 | 171 | 154 |
|
Zinc
|
Metal in concentrate
|
M lbs
| | | | | | 204 | 180 |
^ Guidance / Forecast.
- Subscription is required.
Operational Metrics:
| Metrics | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 |
|
Ore tonnes mined
| ...... | ...... | 751,681 t | 708,263 t | 721,503 t | 580,411 t |
|
Tonnes milled
| ...... | ...... | 739,849 t | 724,995 t | 657,933 t | 590,083 t |
|
Daily milling capacity
| ...... | ...... | 2,000 t | 2,000 t | 2,000 t | 1,900 t |
- Subscription is required.
Reserves at December 31, 2021:
The Perkoa Underground Mine Mineral Reserve estimate is reported based on planned stopes with a net smelter return cutoff value of $90/tonne, with an average zinc price of $1.39 per pound.
The Perkoa Underground Mine Mineral Resource estimate is reported based on a cut-off grade of 5% zinc equivalent.
| Category | Tonnage | Commodity | Grade | Contained Metal |
|
Proven
|
0.73 Mt
|
Zinc
|
11.31 %
|
181 M lbs
|
|
Probable
|
0.23 Mt
|
Zinc
|
9.45 %
|
48 M lbs
|
|
Proven & Probable
|
0.96 Mt
|
Zinc
|
10.86 %
|
229 M lbs
|
|
Measured
|
1.51 Mt
|
Zinc
|
12.72 %
|
424 M lbs
|
|
Indicated
|
1.2 Mt
|
Zinc
|
9.48 %
|
251 M lbs
|
|
Measured & Indicated
|
2.71 Mt
|
Zinc
|
11.29 %
|
675 M lbs
|
|
Inferred
|
0.47 Mt
|
Zinc
|
8.51 %
|
88 M lbs
|
Corporate Filings & Presentations:
- Subscription is required.
- Subscription is required.