Mine Type
Ownership
|
Tons
(000) |
Silver
(oz/ton) |
Gold
(oz/ton) |
Lead
(%) |
Zinc
(%) |
Silver
(000 oz) |
Gold
(000 oz) |
Lead
(Tons) |
Zinc
(Tons) | |
|---|---|---|---|---|---|---|---|---|---|
| Proven Reserves (2, 6) |
–
|
– |
–
|
– |
– |
– |
– |
– |
– |
| Probable Reserves (2, 6)
|
2,197
|
22.5 |
0.01
|
2.4 |
2.2 |
49,473
|
13 |
52,520 |
49,320 |
| Proven & Probable Reserves (2, 6)
|
2,197 |
22.5 |
0.01
|
2.4 |
2.2 |
49,473 |
13 |
52,520 |
49,320 |
| Measured Resources (12, 16) |
– |
– |
– |
– |
– |
– |
– |
– |
– |
| Indicated Resources (12, 16) |
4,601
|
8.0
|
0.007
|
1.0
|
4.0
|
32,288
|
29
|
39,540
|
163,130
|
| Measure & Indicated Resources (12, 16) |
4,601 |
8.0 |
0.007 |
1.0 |
4.0 |
32,288 |
29 |
39,540
|
163,130 |
| Inferred Resources (12, 16) |
2,441 |
10.4 |
0.003 |
0.9 |
2.1 |
25,478 |
8 |
22,380 |
51,000 |
Totals may not represent the sum of parts due to rounding.
(2) Mineral reserves are based on $17/oz silver, $1600/oz gold, $0.90/lb lead, $1.15/lb zinc, unless otherwise stated. All Mineral Reserves are reported in-situ with estimates of mining dilution and mining loss.
(6) The reserve NSR cut-off value at Keno Hill is $244.24/ton (CAN$350/tonne), Metallurgical recovery: 93% for silver, 25% for gold, 93% for lead, 72% for zinc; US$/CAN$ exchange rate: 1:1.3.
Note: All estimates are in-situ except for the proven reserves at Greens Creek which are in surface stockpiles. Mineral resources are exclusive of reserves.
(12) Mineral resources are based on $1700/oz gold, $21/oz silver, $1.15/lb lead, $1.35/lb zinc and $3.00/lb copper, unless otherwise stated.
(16) The resource NSR cut-off value at Keno Hill is $129.10/ton (CAN$185/tonne); using minimum width of 4.9 feet (1.5m); metallurgical recovery: 93% for silver, 25% for gold, 93% for lead, 72% for zinc; US$/CAN$ exchange rate: 1:1.3.
Between 1913 and 1989, Keno Hill produced over 200 Moz of silver with average grades of 44 oz/t, making it the second-largest historical silver producer in Canada. Today, it boasts significant Mineral Resources at grades far higher than most of the world’s primary silver producers.
There has been active exploration and development of the Keno Hill Silver District since 2006. During that time, there has been several significant discoveries including the Flame and Moth and Bermingham deposits that form the backbone of Hecla Yukon’s current mining operations. This exploration success at the Bermingham and Flame & Moth deposits demonstrates the potential to continue growing the District’s mineral resource.
Under a unique contractual agreement with the Government of Canada, Hecla can explore, develop, and produce from historic and newly discovered deposits within the District. The Government of Canada indemnifies the potential liabilities associated with the historic operations in the District under the terms and conditions of the commercial agreement subject to the requirement for ERDC to develop, permit and implement the Site Reclamation Plan.
The addition of Alexco Resource increases Hecla’s silver exposure by increasing proven and probable silver reserves 19% to 237 million ounces, measured, and indicated resources 24% to 257 million ounces and inferred resources 7% to 523.7 million ounces.
The Keno Hill Silver District is in the central Yukon, which is characterized by subarctic continental climate with cold winters and warm summers. Annual precipitation averages 28 cm and half of this falls as snow, which starts to accumulate in October and remains until May or June. The landscape of the District is characterized by rolling hills and mountains with a relief of up to 1,600 m, the highest of which is Keno Hill at 1,975 m.
Mineralization in the District is of the polymetallic silver-lead-zinc vein type where multiple pulses of hydrothermal fluids or fluid boiling, probably related to repeated reactivation and breccia formation along the host fault structures, have formed a series of vein stages with differing mineral assemblages and textures. Supergene alteration may have further changed the nature of the mineralogy in the veins. Much of the supergene zone may have been removed due to glacial erosion. In general, common gangue minerals include (manganiferous) siderite and, to a lesser extent, quartz, and calcite. Silver predominantly occurs in argentiferous galena and argentiferous tetrahedrite (freibergite).
In some assemblages, silver is also found as native silver, in polybasite, stephanite, and pyrargyrite. Lead occurs in galena and zinc in sphalerite, which can be either an iron-rich or iron-poor variety. Other sulphides include pyrite, pyrrhotite, arsenopyrite, and chalcopyrite. The Keno Hill mining camp has long been recognized as a polymetallic silver-lead-zinc vein district with characteristics similar to other well-known mining districts in the world.
