Hecla silver reserves highest in history
COEUR d'ALENE — Hecla Mining Company reported the highest silver reserves in its more than 130-year history on Feb. 14 and provided an update on its exploration programs during the fourth quarter 2022 and plans for 2023.
RESERVES & RESOURCES HIGHLIGHTS
• Silver reserves increased to more than 240 million ounces with the addition of Keno Hill’s almost 50 million silver ounces.
• Gold reserves decreased by 6% due to a higher cut-off grade at Casa Berardi reflecting rising costs.
• Measured and indicated silver and gold resources increased 6% with the inclusion of Keno Hill.
• Inferred resources are mostly unchanged with increases of 3% for silver and 1% for gold.
EXPLORATION HIGHLIGHTS
• Exploration drilling at Keno Hill focused on initial drill testing of new targets at the Silver King, Coral-Wigwam, and Hector-Calumet confirmed the occurrence of favorable vein structures and high-grade silver mineralization in all three areas.
• Exploration and definition drilling at Greens Creek defined and expanded mineralization on strike with strong assay results from the Southwest Bench, 200 South, East, West, and Upper Plate ore zones.
• Surface exploration drilling at Casa Berardi identified a mineralized smoky quartz vein system in the 154 Zone while underground drilling in the West Mine identified high grade gold in the 118 Zone.
“Hecla’s silver reserves are an all-time high,” said Phillips S. Baker Jr., president and CEO. “In the past 15 years, we have replaced the 213 million ounces mined and yet have almost 5 times the reserves we had at the start of 2008. That is over 400 million ounces of silver that we have replaced and grown. We now have a half dozen silver properties to explore, primarily in the US and Canada, the most recent addition being the 88 square mile Keno Hill project in the Yukon.”
Baker continued, “Keno Hill’s 2022 exploration results are particularly remarkable with only three targets drilled that all resulted in three meaningful, high-grade discoveries. This reflects the quality of the land position and the knowledge of the long-standing team who have taken their experience at Bermingham and applied it to the new targets. These initial results exceed our already high expectations for the exploration potential of the district.”
“Hecla has the largest silver reserve in the United States, the highest grade and largest primary silver reserve in Canada, the best silver exploration potential in both countries, and we produce 40% of all the silver mined on in the United States and expect to produce the same percentage of Canada’s production next year. With silver’s importance in the energy transition to renewables, Hecla is well positioned long into the future,” Baker said.
YEAR-END 2022 RESERVES AND RESOURCES
2022 proven and probable silver reserves were the highest in Hecla’s history at more than 240 million ounces.
On a consolidated basis, the Company replaced the 14 million ounces of silver produced during the year and increased proven and probable reserves by 21%, or 41 million ounces over 2021. The increase was primarily due to the acquisition of Keno Hill in Canada’s Yukon Territory. The Company’s gold production of more than 180,000 ounces was not replaced and proven and probable reserves declined 6% to 2.6 million ounces due to cost increases which increased the cut-off grade at Casa Berardi. Zinc production was replaced, and reserves increased 4% to 944 thousand tons. Lead production of 55 thousand tons was replaced with an increase of 7% to 785 thousand tons of reserves.
Reserve metal price assumptions for 2022 were $17/oz silver, $1,600/oz gold, $1.15/lb zinc, and $0.90/lb lead, unchanged from 2021.
Measured and indicated silver ounces increased 6% to 219 million ounces with increases at Greens Creek and the addition of Keno Hill which offset the decrease due to conversion of material to reserves at Lucky Friday. Measured and indicated gold ounces also increased 6% to 3.7 million ounces due mostly to increases at Casa Berardi.
Inferred silver resources increased 3% to 504 million ounces while inferred gold resources increased 1% to 5.7 million ounces due to increases at Greens Creek, Casa Berardi, and the inclusion of Keno Hill.
Resource metal price assumptions for 2022 were $21/oz silver, $1700/oz gold, $1.35/lb zinc and $1.15/lb lead, and $3/lb copper, also unchanged from 2021.
Greens Creek
At Greens Creek, 2022 production was not replaced, where silver, gold, zinc, and lead reserves decreased by 7%, 1%, 4%, and 6%, respectively, over 2021 reserves. Lower margin material and material adjacent to historically mined areas with unknown backfill conditions was removed. A study is reviewing if some of this material may be returned to reserve.
Measured and indicated silver resources at year-end 2022 were 109 million ounces, a 2% increase over 2021 due to drilling and resource conversion. Inferred silver resources increased 5% from exploration drilling to a total of 29 million ounces.
Casa Berardi
At Casa Berardi, mining depletion was not replaced, and gold reserves decreased 10% to 1.6 million ounces due to increased costs which increased cut-off grades.
Measured and indicated gold resources increased 19% to 1.3 million ounces due drilling as well as the cutoff grade converting material from reserves. Inferred gold resources increased 4% from exploration drilling.
Lucky Friday
At the Lucky Friday, mining of 4.8 million ounces of silver was replaced, and proven and probable silver reserves are unchanged from 2021 at 74.7 million ounces of silver. Proven and Probable lead reserves increased 3% to 468 thousand tons and zinc reserves increased 10% to 200 thousand tons.
Measured and indicated silver resources decreased 27% to 58 million ounces; lead and zinc measured and indicated resources decreased 23% and 27%, respectively. Decreases in measured and indicated resources are due to conversion to reserves (4.9 million silver ounces, 39 thousand lead tons, and 28 thousand zinc tons) and increased cut-off grades removing some material.
Inferred resources decreased year-over-year and include 31 million ounces of silver, a decrease of 25%; 225 thousand tons of lead, a decrease of 28%; and 85 thousand tons of zinc, a decrease of 35%. Decreases in inferred resources is mostly due to increased costs and increased cut-off grades along the edges of the resources and at the higher elevations of the 30 Vein. Drilling of inferred resources on the 30 Vein also converted material to higher resource classes and added 3 million ounces to reserve.
Keno Hill
The acquisition of Keno Hill added nearly 50 million silver ounces to Hecla’s reserve base along with 53 thousand tons of lead and 49 thousand tons of zinc. This is an increase of approximately 12 million silver ounces or 33% over the reserves identified at the time of acquisition. The increase is due primarily to infill drilling of the Deep Northeast Zone at Bermingham.
In addition to the increased reserves, Keno Hill added 32 million silver ounces to measured and indicated resources and 26 million silver ounces to inferred resources.
A breakdown of the Company’s reserves and resources is set out in Table A at the end of this news release.
EXPLORATION AND PRE-DEVELOPMENT UPDATE
Exploration and pre-development expenses totaled $6.9 million for the fourth quarter and $46.0 million for the year 2022.
Exploration and pre-development expenses totaled $6.9 million for the fourth quarter and $46.0 million for the year 2022.
Exploration Update for Fourth Quarter, 2022
Keno Hill, Yukon Territory
At Keno Hill, two surface core drills confirmed high-grade silver mineralization at the Silver King, Coral-Wigwam, and Hector-Calumet targets (Figure 1). Mineralization at all three target areas are broad structural analogs to the nearby Bermingham deposit representing a successful application of the ore control model where northeast trending transverse structures intercept east-northeast trending longitudinal structures. While most known high-grade mineralization is hosted within the basal quartzite, several of the mineralized intercepts at both Coral Wigwam and Silver King are hosted above the favorable host. Also, the Silver King intercepts are located on the longitudinal-oriented structures. So, these results require a reevaluation of other targets in the same setting.
Coral Wigwam: At Coral Wigwam, the Walleye Vein assay results to date include:
• Drillhole K-22-0825 (Walleye): 101 oz/ton silver, 0.1% zinc, 0.1% lead, and 0.3% copper over 7.3 feet estimated true width. This intercept includes a narrower zone grading 2,522 oz/ton silver, 0.7% zinc, 0.3% lead, and 8.1% copper over 0.3 feet estimated true width.
Hector Calumet: The new Chance Vein was discovered 300 feet to the southeast of the historical 96 million ounce silver producing Hector-Calumet mine. Assay results to date include:
• Drillhole K-22-0829 (Chance): 5 oz/ton silver, 0.5% zinc, and 1.1% lead over 24.6 feet estimated true width. This intercept includes a narrower zone grading 9.6 oz/ton silver, 0.8% zinc, and 2.5% lead over 10.5 feet estimated true width.
• Drillhole K-22-0834 (Chance): 22 oz/ton silver, 6.4% zinc, and 2.3% lead over 2.3 feet estimated true width.
• Drillhole K-22-0837 (Chance): 10.5 oz/ton silver, 4.0% zinc, and 1.1% lead over 11.0 feet estimated true width including 47.2 oz/ton silver, 33.0% zinc, and 0.7% lead over 1.1 feet estimated true width.
Silver King: At Silver King, multiple mineralized veins were intersected including the Adam, No. 5, No. 6, and new No. 6 Splay veins. Significantly, many of these highly mineralized intervals are hosted in historically less productive portions of the Keno Hill stratigraphy that overlay and are projected into the more favorable basal quartzite. Assay results to date include:
• Drillhole K-22-0804 (Adam): 38.8 oz/ton silver, 4.7% zinc, and 1.4% lead over 1.9 feet estimated true width.
• Drillhole K-22-0810 (No. 6 Splay): 7.9 oz/ton silver, 0.9% zinc, and 0.2% lead over 16.3 feet estimated true width including:
• 31.6 oz/ton silver, 1.9% zinc, and 0.3% lead over 3.0 feet estimated true width.
• Drillhole K-22-0810 (No. 6): 19.6 oz/ton silver, 0.2% zinc, and 0.9% lead over 11.7 feet estimated true width including:
• 52.7 oz/ton silver, 0.3% zinc, and 2% lead over 4 feet estimated true width.
• Drillhole K-22-0812 (No. 5): 11 oz/ton silver, and 0.8% lead over 5.5 feet.
Greens Creek, Alaska
At Greens Creek, four underground drills converted resources in the 200 South, East, Gallagher, and West ore zones as well as exploration on the southern extension of the West and Gallagher Fault Block zones (Figure 2). Additionally, two helicopter-supported programs drilled the Upper Plate Zone and Lil’Sore to the northwest of the mine. Assay results were received for the Southwest Bench, 200 South, East, West, and Upper Plate areas and results continue to confirm and expand mineral zones but were not yet included in the reserve calculation.
Upper Plate Zone: Surface exploration drilling expanded mineralization 40 feet to the west from previous mineralized intercepts. Highlights from this drilling include:
• 8.9 oz/ton silver, 0.14 oz/ton gold, 12.1% zinc and 4.8% lead over 12.6 feet.
• 11.9 oz/ton silver, 0.17 oz/ton gold, 17.3% zinc, and 7.8% lead over 7.6 feet.
200 South Zone: Drilling tested 200 feet of strike length and infilled between existing drill intercepts. Highlights include:
• 35.0 oz/ton silver, 0.56 oz/ton gold, 9.2% zinc, and 4.5% lead over 13.0 feet.
East Zone: Drilling infilled over a strike length of 250 feet and tested the lower portion of the East Zone. Highlights include:
• 15.9 oz/ton silver, 0.10 oz/ton gold, 15.6% zinc, and 7.7% lead over 15.8 feet.
• 26.2 oz/ton silver, 0.23 oz/ton gold, 10.2% zinc, and 3.6% lead over 4.0 feet.
• 18.7 oz/ton silver, 0.10 oz/ton gold, 7.5% zinc, and 3.3% lead over 16.4 feet.
Casa Berardi, Quebec
At Casa Berardi, up to six underground core drills and two surface core drills were focused on definition and exploration drilling in multiple zones and targets in the West Mine, Principal Mine, and East Mine areas.
West Mine: Underground drilling targeted the 113 and 118 zones. Highlights include:
• 113 Zone: 0.12 oz/ton gold over 12.1 feet, including — 0.21 oz/ton gold over 6.2 feet.
• 113 Zone: 0.11 oz/ton gold over 12.5 feet.
• 118 Zone: 0.39 oz/ton gold over 10.8 feet, including — 3.32 oz/ton gold over 1.0 feet.
• 118 Zone: 0.29 oz/ton gold over 12.5 feet, including — 1.14 oz/ton gold over 3.0 feet.
East Mine: Underground drilling targeted the 148-01 lens while surface exploration drilling targeted the 152 Zone and discovered the 154 zone. This new zone is near the contact between a greywacke sedimentary unit and an andesitic lava flow with up to 5% arsenopyrite and is open in all directions. Highlights include:
• 148 Zone: 0.27 oz/ton gold over 20.3 feet.
• 154 Zone: 0.15 oz/ton gold over 15.5 feet.
2023 Exploration Program
Exploration and pre-development expenditures are anticipated to be $32.5 million in 2023, with about 70% of exploration expenditures being deployed at Greens Creek (26%), Casa Berardi (21%), Keno Hill (14%) and Aurora (6%).
At Greens Creek, underground definition drilling will focus on the 200 South, Upper Plate, 9A, West, Northwest West, Southwest, and East ore zones while underground exploration will focus on the 200 South, Gallagher, Gallagher Fault Block zones, the northern end of the East Ore Zone and up dip from the northern end of the West Ore Zone. Surface exploration drilling will focus on the Upper Plate Zone, the western part of the Gallagher Fault zone, the eastern part of the East Zone and the Lil’Sore prospect, which is the most anomalous and untested target away from the mine.
At Keno Hill, underground definition drilling will be at the Bermingham Bear Zone and the Flame & Moth Lightning Zone while surface exploration will focus on expanding the high-grade veins at the Hector-Calumet, Coral-Wigwam and Silver King target areas, the upflow zones below the Bermingham NE Zone and the untested zones above the Bermingham Deep NE Zone.
At Casa Berardi, underground definition drilling will be at the 118, 121, 123, 146 and 148 Zones. Exploration drilling will be on the high-grade extensions of the Lower Inter, 113-116, 118, 123, 134, 146, 148 and 152 to 157 zones. Regional surface exploration drilling will test anomalies from the sonic drilling program in the east and west block.
Nevada exploration is primarily at Aurora following up on Juniata and Chesco and drill testing the Sawtooth Ridge and Humboldt Offset target.