Overview
Stage | Preliminary Economic Assessment |
Mine Type | Open Pit |
Commodities |
|
Mining Method |
|
Mine Life | 25 years (as of Jan 1, 2017) |
The Spectrum-GJ Cu-Au project area comprises a combination of the properties: the Spectrum property and the GJ property.
On May 1, 2020, Skeena reported the closing of the asset purchase agreement between Skeena and Newcrest Red Chris Mining Limited (“Newcrest”) dated February 3, 2020 to sell 100% of the Company’s interest in the GJ Copper-Gold Property (the “GJ Property”) to Newcrest for C$7.5 million paid in cash, and the assumption by Newcrest of future payment obligations and royalties on the GJ Property.
On April 8, 2021, Skeena announced that a new conservancy to protect the environmental and wildlife of Tahltan territory had been created in an area of northwest BC known as the Ice Mountain Lands, also known as the Spectrum property. Skeena returned its mineral tenures on the Spectrum property, enabling the Tahltan Central Government (“TCG”), Skeena, the Nature Conservancy of Canada and BC Parks Foundation to collaborate and create this conservancy. |
Source:
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Skeena Resources Limited holds a 100% interest in the Spectrum property and an option to acquire a 100% interest in the adjoining GJ property.
On May 1, 2020, Skeena reported the closing of the asset purchase agreement between Skeena and Newcrest Red Chris Mining Limited (“Newcrest”) dated February 3, 2020 to sell 100% of the Company’s interest in the GJ Copper-Gold Property (the “GJ Property”) to Newcrest for C$7.5 million paid in cash, and the assumption by Newcrest of future payment obligations and royalties on the GJ Property.
Contractors
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Deposit Type
- Porphyry
- Vein / narrow vein
Summary:
The Project Area hosts two principal styles of mineralization that have been the target of past and current exploration. The first and older style is porphyry Cu-Au mineralization related to intrusion and alteration by Late Triassic alkalic to sub-alkalic diorite to monzonite dykes and stocks exemplified by the Central Zone and Donnelly Deposit. The second comprises later, structurallyhosted and high-grade gold zones associated with shearing, fracture zones and quartz-carbonate vein/fault controlled pyrite, arsenopyrite, sphalerite, galena and chalcopyrite hosted by altered volcanic units and monzonite dykes.
Porphyry-Style Mineralization - Central Zone
Porphyry-style Cu-Au mineralization occurs within a north-south trending, moderately west dipping and fault-bounded structural panel of Triassic Stuhini volcaniclastic lithologies intruded by syn- to late-mineral monzonite dykes. Porphyry- style mineralization has been defined over a strike length of 1,000 m, with widths of 70 m to 200 m, it has been tested to 400 m downdip and it remains open along strike and downdip.
Mineralization occurs as quartz-pyrite-chalcopyrite with or without magnetite veinlets, stockworks, fracture fills and fine grained disseminations of pyrite and chalcopyrite. Metal grades appear to be directly related to the abundance of quartz-sulphide-magnetite vein development.
Porphyry-Style Mineralization - Donnelly Deposit
Of the many porphyry Cu-Au prospects l ........

Summary:
Conventional truck and shovel open pit mining was selected because, overall, it represents the least risk, most sustainable option from both economic and environmental perspectives.
Flow Sheet:
Flow Sheet:
Summary:

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Projected Production:
Commodity | Units | LOM |
Copper
|
B lbs
| 1 |
Gold
|
M oz
| ......  |
Silver
|
M oz
| ......  |
All production numbers are expressed as payable metal.
Operational Metrics:
Metrics | |
Stripping / waste ratio
| 0.71 * |
Daily milling capacity
| 30,000 t * |
Waste tonnes, LOM
| 134.71 Mt * |
Ore tonnes mined, LOM
| 217.23 Mt * |
Total tonnes mined, LOM
| 351.14 Mt * |
Tonnes milled, LOM
| 213.74 Mt * |
* According to 2017 study.
Reserves at January 6, 2017:
Category | Tonnage | Commodity | Contained Metal |
Indicated
|
246.4 Mt
|
Copper
|
1,303 M lbs
|
Indicated
|
246.4 Mt
|
Gold
|
3.08 M oz
|
Indicated
|
246.4 Mt
|
Silver
|
15.67 M oz
|
Inferred
|
58.1 Mt
|
Copper
|
161.5 M lbs
|
Inferred
|
58.1 Mt
|
Gold
|
0.73 M oz
|
Inferred
|
58.1 Mt
|
Silver
|
2.98 M oz
|
Commodity Production Costs:
| Commodity | Units | Average |
Cash costs
|
Copper
|
USD
|
1.37 / lb *†
|
Cash costs
|
Gold
|
USD
|
461.56 / oz *†
|
All-in costs
|
Copper
|
USD
|
1.81 / lb *†
|
All-in costs
|
Gold
|
USD
|
730.97 / oz *†
|
Assumed price
|
Copper
|
USD
|
2.75 / lb *
|
Assumed price
|
Silver
|
USD
|
17.8 / oz *
|
Assumed price
|
Gold
|
USD
|
1.25 / oz *
|
* According to 2017 study / presentation.
† Net of By-Product.
Operating Costs:
| Units | 2017 |
Total operating costs ($/t milled)
|
CAD
| 14.3 * |
* According to 2017 study.
2017 Study Costs and Valuation Metrics :
Metrics | Units | LOM Total |
Pre-Production capital costs
|
$M CAD
|
......
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Sustaining CapEx
|
$M CAD
|
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Total CapEx
|
$M CAD
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......
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After-tax Cash Flow (LOM)
|
$M CAD
|
......
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Pre-tax NPV @ 8%
|
$M CAD
|
......
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After-tax NPV @ 8%
|
$M CAD
|
......
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Pre-tax IRR, %
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......
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After-tax IRR, %
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......
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Pre-tax payback period, years
|
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......
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After-tax payback period, years
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......
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Corporate Filings & Presentations:
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