HECLA MINING CODE

Total sales for the three and nine months ended September 30, 2024 and 2023 were as follows:

Environmental remediation services revenue is generated by performing remediation work in the historical Yukon Territory mining district on behalf of the Canadian government. The scope and estimated cost of all work is agreed to in advance by the Canadian government, and the expenses incurred are essentially passed through to the government for reimbursement with minimal margin generated by our subsidiary in performing this work.

Total metal sales for the three and nine months ended September 30, 2024 and 2023, and the approximate variances attributed to differences in metals prices, sales volumes and smelter terms, were as follows:

The fluctuations in sales for the three and nine months ended September 30, 2024 compared to the same periods in 2023 were primarily due to the following two reasons:

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Higher average realized prices for precious metals and lower realized base metals prices during the three and nine months ended September 30, 2024, compared to the same periods in 2023. The table below summarizes average spot prices and our average realized prices for the commodities we sell:

Average realized prices typically differ from average market prices primarily because concentrate sales are generally recorded as revenues at the time of shipment at forward prices for the estimated month of settlement, which differ from average market prices. Due to the time elapsed between shipment of concentrates and final settlement with the customers, we must estimate the prices at which sales of our metals will be settled. Previously recorded sales are adjusted to estimated settlement metals prices each period through final settlement. We recorded net positive price adjustments to provisional settlements of $5.0 million and $19.5 million for the three and nine months ended September 30, 2024, respectively, and $8.1 million and $12.3 million for the three and nine months ended September 30, 2023, respectively. The price adjustments related to silver, gold, zinc and lead contained in our concentrate shipments were partially offset by gains and losses on forward contracts for those metals. See Note 8 of Notes to Condensed Consolidated Financial Statements (Unaudited)for more information. The gains and losses on these contracts are included in revenues and impact the realized prices for silver, gold, lead and zinc. Realized prices are calculated by dividing gross revenues for each metal (which include the price adjustments and gains and losses on the forward contracts discussed above) by the payable quantities of each metal included in concentrate, doré and carbon material shipped during the period.

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Higher quantities of silver sold during the three and nine months ended September 30, 2024, compared to the same periods in 2023, primarily due to a full third quarter of Lucky Friday sales in 2024 compared to 2023 when production was suspended in August 2023 following a fire in the secondary egress that suspended operations for the remainder of 2023. See The Greens Creek Segment, The Lucky Friday Segment, The Keno Hill Segment, and Casa Berardi Segment sections below for more information on metal production and sales volumes at each of our operating segments. Total metals production and sales volumes for each period are shown in the following table:

The difference between what we report as “ounces/tons produced” and “payable ounces/tons sold” is attributable to the difference between the quantities of metals contained in the concentrates we produce versus the portion of those metals actually paid for by our customers according to the terms of our sales contracts. Differences can also arise from inventory changes incidental to shipping schedules, or variances in ore grades which impact the amount of metals contained in concentrates produced and sold.

Sales, total cost of sales, gross profit (loss), Cash Cost, After By-product Credits, per Ounce (“Cash Cost”) (non-GAAP) and AISC (non-GAAP) at our operating units for the three and nine months ended September 30, 2024 and 2023 were as follows (in thousands, except for Cash Cost and AISC):

(1)

A reconciliation of these non-GAAP measures to total cost of sales, the most comparable GAAP measure, can be found below in Reconciliation of Total Cost of Sales (GAAP) to Cash Cost, Before By-product Credits and Cash Cost, After By-product Credits (non-GAAP) and All-In Sustaining Cost, Before By-product Credits and All-In Sustaining Cost, After By-product Credits (non-GAAP).

(2)

The calculation of AISC for our consolidated silver properties includes corporate costs for general and administrative expense and sustaining capital.

(3)

For the three and nine months ended September 30, 2024, Other includes sales of $7.3 million and $15.1 million, respectively, and total cost of sales of $6.8 million and $14.3 million, for the three and nine months ended September 30, 2024, respectively, from our environmental remediation services in the Yukon. For the three and nine months ended September 30, 2023, Other includes sales of $1.1 million and $3.0 million for the three and nine months ended September 30, 2023, respectively, and cost of sales of $0.9 million and $2.7 million, respectively, for the three and nine months ended September 30, 2023, related to our environmental remediation services business and Nevada operations.

While revenue from zinc, lead and gold by-products is significant, we believe that identification of silver as the primary product of Greens Creek, Lucky Friday and Keno Hill is appropriate because:

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silver has historically accounted for a higher proportion of revenue than any other metal and is expected to do so in the future;

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we have historically presented the Greens Creek and Lucky Friday units as primary silver producers, based on the original analysis that justified putting the project into production, and the same analysis applies to the Keno Hill unit. Further we believe that consistency in disclosure is important to our investors regardless of the relationships of metals prices and production from year to year;

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metallurgical treatment maximizes silver recovery;

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the Greens Creek, Lucky Friday and Keno Hill deposits are massive sulfide deposits containing an unusually high proportion of silver; and

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in most of their working areas, Greens Creek, Lucky Friday and Keno Hill utilize selective mining methods in which silver is the metal targeted for highest recovery.

Accordingly, we believe the identification of gold, lead, zinc and copper as by-product credits at Greens Creek, Lucky Friday and Keno Hill is appropriate because of their lower economic value compared to silver and due to the fact that silver is the primary product we intend to produce at those locations. In addition, we have not consistently received sufficient revenue from any single by-product metal to warrant classification of such as a co-product.

We periodically review our revenues to ensure that reporting of primary products and by-products is appropriate. Because for Greens Creek, Lucky Friday and Keno Hill we consider zinc, lead, gold and copper to be by-products of our silver production, the values of these metals offset operating costs within our calculations of Cash Cost, After By-product Credits, per Silver Ounce and AISC, After By-product Credits, per Silver Ounce. We currently do not report Cash Cost, After By-product Credits, per Silver Ounce and AISC, After By-product Credits, per Silver Ounce for our Keno Hill operation as it is in the production ramp-up phase and has not met our definition of commercial production, and accordingly it is excluded from our consolidated Cash Cost, After By-product Credits, per Silver Ounce and AISC, After By-product Credits, per Silver Ounce. We define an operation as being in commercial production upon achievement of the following criteria:

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Completion of operational commissioning of each major mine and mill component;

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Demonstrated ability to mine and mill consistently and without significant interruption, defined as 75% of historical production levels or mill design capacity over a period of 30 days;

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Silver recoveries are at or near expected steady-state production levels;

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All major capital expenditures have been completed; and

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A significant portion of available funding is directed towards operating activities.

Determination of when these criteria have been met requires the use of judgment, and our definition of commercial production may differ from that of other mining companies.

We believe the identification of silver as a by-product credit is appropriate at Casa Berardi because of its lower economic value compared to gold and due to the fact that gold is the primary product we intend to produce there. In addition, we do not receive sufficient revenue from silver at the Casa Berardi mine to warrant classification of such as a co-product. Because we consider silver to be a by-product of our gold production at Casa Berardi, the value of silver offsets operating costs within our calculations of Cash Cost, After By-product Credits, per Gold Ounce and AISC, After By-product Credits, per Gold Ounce.

We reported net income applicable to common stockholders of $1.6 million for the three months ended September 30, 2024, compared to a net loss applicable to common stockholders of $22.6 million in the comparable period in 2023. The following were the significant drivers of the change:

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Consolidated gross profit increased by $25.8 million. See The Greens Creek Segment, The Lucky Friday Segment, The Keno Hill Segment, and The Casa Berardi Segment sections below for a discussion on the key drivers by operating unit.

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Ramp-up and suspension costs decreased by $7.3 million as the prior period included $12.0 million of suspension costs related to the temporary suspension of operations at Lucky Friday due to the underground fire, whereas the current period primarily contained costs related to Keno Hill's ramp-up activities and increased by $4.9 million over the comparable period in 2023.

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Other operating income, net increased by $15.4 million primarily due to $14.8 million of insurance proceeds received during the quarter related to the Lucky Friday fire.

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Fair value adjustments, net increased by $10.1 million primarily due to $3.3 million in unrealized gains on our marketable equity securities portfolio in 2024 compared to an unrealized loss of $4.2 million in the comparable period in 2023 and an unrealized gain of $0.4 million on our undesignated derivative contracts compared to a $2.2 million unrealized loss when compared to the comparable period in 2023.

The positive movements mentioned above were partly offset by:

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A $14.5 million write down of property, plant and equipment which had no salvage value. Of this amount, $13.9 million related to the Lucky Friday remote vein miner machine for which (i) we no longer had a use following the success of the UCB mining method at Lucky Friday, (ii) we had been unsuccessful in locating a buyer, and (iii) the vendor advised us during the period that it would discontinue support for the program.

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Net foreign exchange loss increased by $7.4 million to a loss of $3.2 million, compared to a gain of $4.2 million in the comparable period, reflecting the strengthening of the Canadian dollar against the US dollar in 2024, compared to a devaluation in the comparable period in 2023 , and related impact on the revaluation of our Canadian monetary assets and liabilities.

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Income and mining tax expense increased by $13.0 million due to higher taxable income generated by our US tax group.

We reported net income applicable to common stockholders of $23.5 million for the nine months ended September 30, 2024, compared to a net loss applicable to common stockholders of $41.7 million in the comparable period in 2023. The following were the significant drivers of the change:

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Ramp-up and suspension costs decreased by $14.9 million as costs incurred in the prior period related to the temporary suspension of operations at Casa Berardi for 20 days resulting from certain forest lands and access road closures due to forest fires and the temporary suspension of operations at Lucky Friday due to an underground fire were not incurred in 2024.

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Other operating income, net increased by $45.4 million primarily due to $50.0 million of insurance proceeds received during the period related to the Lucky Friday fire. Other operating income, net in the prior period included $5.9 million of insurance proceeds related to a coverage lawsuit.

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Fair value adjustments, net increased by $12.6 million primarily due to $9.0 million of unrealized gains on our marketable equity securities portfolio in 2024 compared to an unrealized loss of $7.6 million the comparable period in 2023. This was partially offset by unrealized losses on undesignated derivative contracts of $2.1 million in 2024 compared to an unrealized gain of $1.8 million in the comparable period in 2023.

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Net foreign exchange gain increased by $3.0 million to $3.4 million reflecting the continued strengthening of the US dollar against the Canadian dollar, and related impact on the revaluation of our Canadian monetary assets and liabilities.

The positive movements mentioned above were partly offset by:

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A $14.5 million write down of property, plant and equipment which had no salvage value. Of this amount, $13.9 million related to the Lucky Friday remote vein miner machine for which (i) we no longer had a use following the success of the UCB mining method at Lucky Friday, (ii) we had been unsuccessful in locating a buyer, and (iii) the vendor advised us during the period that it would discontinue support for the program.

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General and administrative expenses increased by $5.9 million, primarily related to non-recurring non-cash compensation costs associated with our former CEO's retirement in the second quarter and higher incentive compensation accruals.

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Interest expense increased by $4.9 million as higher amounts were drawn on our revolving credit facility.

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Income and mining tax expense increased by $15.4 million due to higher taxable income generated by our US tax group.

Greens Creek

(1)

A reconciliation of these non-GAAP measures to total cost of sales, the most comparable GAAP measure, can be found below in Reconciliation of Total Cost of Sales (GAAP) to Cash Cost, Before By-product Credits and Cash Cost, After By-product Credits (non-GAAP) and All-In Sustaining Cost, Before By-product Credits and All-In Sustaining Cost, After By-product Credits (non-GAAP).

The $6.8 million increase in gross profit for the three months ended September 30, 2024, compared to the same period in 2023 was primarily due to higher realized sales prices for silver and gold, partially offset by lower metals sales volumes. Capital additions were largely consistent with the comparable period, decreasing by $0.6 million.

The $8.0 million increase in gross profit for the nine months ended September 30, 2024, compared to the same period in 2023 was primarily due to higher realized sales prices for silver and gold, partially offset by lower metals sales volumes. Capital additions increased by $4.5 million in the same period primarily due to primary ore access development.

Production during the three and nine months ended September 30, 2024, declined primarily due to a combination of unplanned semi-antogenous grinding ("SAG") mill maintenance and lower grade. Throughput for the quarter averaged 2,314 tons per day, a decline of 7% as various mill maintenance projects were completed during the quarter, including SAG liners inspection, bolts retorquing, as well as work completed during a 7-day unscheduled maintenance event, of which 5 were in September. The mill restarted during early October and we expect similar production levels in the fourth quarter as during the quarter ended September 30, 2024.

The charts below illustrate the factors contributing to Cash Cost, After By-product Credits, per Silver Ounce for Greens Creek:

For the three months ended September 30, 2024, the decrease in Cash Cost, After By-product Credits, per Silver Ounce and AISC, After By-product Credits, per Silver Ounce was primarily due to an increase in by-product credits, benefiting from higher realized gold prices, partly offset by higher production costs and lower ounces produced.

For the nine months ended September 30, 2024, Cash Cost, After By-product Credits, per Silver Ounce was slightly lower compared to the comparable period from 2023, as higher production costs were offset by higher by-product credits on a per ounce basis, benefiting from higher realized gold prices. In addition to the factors impacting Cash Cost per Silver Ounce, AISC, After By-product Credits, per Silver Ounce was also impacted by higher sustaining capital.

Lucky Friday

(1)

A reconciliation of these non-GAAP measures to total cost of sales, the most comparable GAAP measure, can be found below in Reconciliation of Total Cost of Sales (GAAP) to Cash Cost, Before By-product Credits and Cash Cost, After By-product Credits (non-GAAP) and All-In Sustaining Cost, Before By-product Credits and All-In Sustaining Cost, After By-product Credits (non-GAAP).

During August 2023, mining was suspended due to a fire which occurred while repairing an unused station in the #2 ventilation shaft, which is also the secondary egress. By early September, the fire had been extinguished, normal ventilation was reestablished and the workforce recalled. Following evaluation of alternatives, it was determined that in order to safely bring the mine back into production in the most rapid and cost-effective way, a new secondary egress needed to be developed to bypass the damaged portion of the #2 shaft. The new egress involved extending an existing ramp 1,600 feet, installing a 290-foot-long manway raise, and developing an 850-foot ventilation raise. This work resulted in operations being suspended for the remainder of 2023, with the mine restarting production on January 9, 2024, and ramping up to full production during the first quarter. The Company has property and business interruption insurance coverage with an underground sub-limit of $50.0 million, and through September 30, 2024, has received the full coverage amount of $50.0 million. The discussion of Lucky Friday's results below for the nine months ended September 30, 2024 and 2023, has been impacted by the prior suspension of operations.

Gross profit increased by $4.7 million for the three months ended September 30, 2024 compared to the same period in 2023, reflecting a combination of higher sales volumes for all metals and higher realized sales prices for silver, as the mine suspended operations in August 2023 and did not resume operations until January 9, 2024.

Gross profit increased by $9.1 million for the nine months ended September 30, 2024, compared to the same period in 2023, reflecting higher realized prices for silver, and higher sales volumes for all metals produced due to the suspension of mining operations mentioned above.

For both the three and nine month periods ended September 30, 2023, $12.0 million of site specific suspension costs were included within Ramp-up and suspension costs.

Capital additions decreased by $4.3 million for the three months ended September 30, 2024 and decreased by $9.5 million for the three and nine months ended September 30, 2024, respectively, compared to the same periods in 2023. Capital expenditures decreased during 2024 as the prior period included expenditures for bolters, the installation of a service hoist and the coarse ore bunker.

The charts below illustrate the factors contributing to Cash Cost, After By-product Credits, Per Silver Ounce for Lucky Friday:

The increase in Cash Cost, After By-product Credits, per Silver Ounce and AISC, After By-product Credits, per Silver Ounce for the three months ended September 30, 2024, compared to the same period in 2023 was primarily due to higher production costs, partly offset by higher silver production in the current quarter as mining operations were suspended in August 2023. AISC, After By-product Credits, per Silver Ounce was also negatively impacted higher sustaining capital.

The increase in Cash Cost, After By-product Credits, per Silver Ounce and AISC, After By-product Credits, per Silver Ounce for the nine months ended September 30, 2024, compared to the same period in 2023 was primarily due to higher production costs, partly offset by higher silver production in the current year as mining operations were suspended in August 2023 and resumed on January 9, 2024.

Keno Hill

Since acquiring our Keno Hill operations as part of the acquisition of Alexco Resource Corp. ("Alexco") on September 7, 2022, we have focused on development activities, with initial operation of the mill beginning in the second quarter of 2023. The average throughput during the nine months ended September 30, 2024 was 314 tons per day, with silver grades milled of 25.6 ounces per ton. Since commencing production, mill throughput has generally increased as planned, leading to increased levels of production. However, we expect 2025 silver production to remain similar to 2024 as we focus on stakeholder engagement, permitting, infrastructure and capital projects, with production projected to increase again in 2026. The pause in silver production growth at Keno Hill is a direct result of the heap leach failure at Victoria Gold’s Eagle Mine in late June 2024. This failure had several immediate and ongoing impacts on our operations. The primary impact was the Company was forced to suspend milling operations at Keno Hill on August 27, 2024, due to delays in receiving an authorization to construct and a permit modification Keno Hill’s dry stack tailings storage facility (“DSTF”). The delayed authorization and permit were a result of the focus of the Yukon Government (“YG”) and the First Nation of Na-Cho Nyäk Dun (“FNNND”) on Eagle Mine incident response and not on routine permitting matters. Mill operations resumed on October 26, 2024 after receiving the authorization and modification and completing related design and construction work on the DSTF. A second impact of the Eagle Mine incident has been expression of strong positions by the FNNND on continuing and future mining activities at projects within their Traditional Territory, where Keno Hill is located, including a call to halt mining production. We are committed to responsible and sustainable mining that governments and local communities support. As such, the projected flat production levels at Keno Hill for 2025 should allow us to focus on stakeholder outreach and ensuring we have local support for increasing production levels by 2026. In 2025, the Company's environmental remediation services group is also expected to increase construction activities, adding incremental demand on Keno Hill's infrastructure and resources.

During the three months ended September 30, 2024, Keno Hill recorded sales and total cost of sales of $19.8 million related to concentrate produced and sold. The third quarter of 2024 had $10.0 million of site-specific ramp-up costs, compared to $5.1 million in the third quarter of 2023, due to the mill shutdown. During the quarter, Keno Hill recorded capital additions of $14.4 million, related to mine development, work on the DSTF and other mining equipment purchases.

During the nine months ended September 30, 2024, Keno Hill recorded sales and total cost of sales of $59.6 million related to concentrate produced and sold. The nine months ended September 30, 2024 and 2023 had $20.4 million of site-specific ramp up costs included in ramp-up and suspension costs. During the current year, Keno Hill recorded capital additions of $39.3 million, primarily related to mine development, work on the DSTF, a surface backfill plant and other mining equipment purchases.

Casa Berardi

(1)

A reconciliation of these non-GAAP measures to total cost of sales, the most comparable GAAP measure, can be found below in Reconciliation of Total Cost of Sales (GAAP) to Cash Cost, Before By-product Credits and Cash Cost, After By-product Credits (non-GAAP) and All-In Sustaining Cost, Before By-product Credits and All-In Sustaining Cost, After By-product Credits (non-GAAP).

As part of the transition of the Casa Berardi mine from a combined underground and open pit operation to an open pit only operation, the lower margin east mine underground operations were closed in July 2023 and, along with mining the 160 open pit, only the higher margin stopes of the west underground mine will be mined until they are exhausted, which is expected to occur in mid-2025, at which time most underground activity is expected to cease. Following the halt to underground mining, Casa Berardi is expected to only produce gold from the 160 open pit, and at lower volumes than historic production levels with production expected to conclude in 2027. We forecast a gap in production commencing in 2027 and lasting until 2032 or later, when no ore is expected to be mined and no revenue is expected. During this hiatus, our focus is expected to be on investing in infrastructure and equipment, permitting and de-watering and stripping two expected new open pits, Principal and West Mine Crown Pillar. Upon conclusion of the hiatus and related permitting and construction, the mine is expected to generate significant free cash flow at current gold prices.

Gross profit increased by $13.9 million to $4.0 million for the three months ended September 30, 2024, compared to a gross loss of $9.9 million in the same period in 2023. The increase in gross profit is primarily related to higher realized prices, partly offset by lower gold ounces sold, and lower depreciation costs in the current quarter due to the west underground mine being fully depreciated during the first half of the year. Capital additions increased by $2.4 million during the quarter, compared to the same period in 2023, primarily related to a tailings dam raise.

Gross loss decreased by $6.2 million to $21.4 million for the nine months ended September 30, 2024, compared to a gross loss of $27.5 million in the same period in 2023. The decrease in gross loss primarily relates to an increase in realized gold prices, partly offset by lower gold ounces sold and a $9.3 million reduction in production costs due to the closure of the east mine in July 2023. These items were partly offset by a $18.8 million increase in depreciation expense, reflecting the west underground mine being fully depreciated during the first half of the year, in line with the initial expectation of underground mining ceasing in the first half of 2024 and $6.3 million in product inventory net realizable value write downs attributable to higher depreciation. Capital additions decreased by $9.8 million during the nine months ended September 30, 2024, compared to the same period in 2023, primarily related to the cessation of capitalization of underground development. The majority of capital additions for the current year are related to a tailings dam raise.

Although Casa Berardi generated gross profit during the third quarter of 2024, it has generated gross losses during the previous eight quarters. This lack of profitability, the expected hiatus in future production discussed above, and the uncertainty surrounding permitting and timing of construction of the new open pits, has caused us to undertake a review of how Casa Berardi fits into the Company’s future strategy. While it is possible we may continue down the path towards future production at the Principal and West Mine Crown Pillar pits, we are also examining potential strategic alternatives.

The charts below illustrate the factors contributing to Cash Cost, After By-product Credits, Per Gold Ounce for Casa Berardi:

The increase in Cash Cost After By-product Credits, per Gold Ounce, for the three months ended September 30, 2024, compared to the same period in 2023 was primarily due to lower gold production and higher production costs. Higher AISC, After By-product Credits, per Gold Ounce reflected lower gold production and higher sustaining capital over the comparable period in 2023.

The increase in Cash Cost After By-product Credits, per Gold Ounce, for the nine months ended September 30, 2024 was primarily related to lower gold production, partly offset by lower production costs from the cessation of underground mining of the east mine during July 2023. Sustaining capital decreased for the nine months ended September 30, 2024, reflecting no underground development and the prior period containing machinery and equipment expenditures related to surface operations positively impacted AISC, After By-product Credits, per Gold Ounce.

Corporate Matters

Income Taxes

During the three and nine months ended September 30, 2024, an income and mining tax provision of $11.5 million and $22.3 million, respectively, resulted in an effective tax rate of 86.7% and 48.3%, respectively. This compares to an income and mining tax benefit of $1.5 million and an income and mining tax provision of $6.9 million which resulted in an effective tax rate of 6.3% and -20.1%, for the three and nine months ended September 30, 2023, respectively. The comparability of our income and mining tax provision and effective tax rate for the reported periods was impacted by multiple factors, primarily: (i) mining taxes; (ii) variations in our income before income taxes; (iii) geographic distribution of that income; (iv) foreign exchange rates including non-recognition of foreign exchange gains and losses; (v) percentage depletion; and (vi) the non-recognition of tax assets. The effective tax rate will fluctuate, sometimes significantly, period to period. The change in the effective tax rate during the three and nine months ended September 30, 2024, compared to the comparable periods in 2023 is primarily related to the reported consolidated income (loss) as well as the losses incurred at our consolidated Alexco subsidiaries, and our Nevada subsidiaries, for which no tax benefit is recognized due to uncertainty surrounding our ability to utilize these future tax benefits.

Each reporting period we assess our deferred tax balances based on a review of long-range forecasts and quarterly activity. A valuation allowance is provided for deferred tax assets for which it is more likely than not the related tax benefits will not be realized. We analyze our deferred tax assets and, if it is determined that we will not realize all or a portion of our deferred tax assets, we record or increase a valuation allowance. Conversely, if it is determined we will ultimately more likely than not be able to realize all or a portion of the related benefits for which a valuation allowance has been provided, all or a portion of the related valuation allowance will be reduced. There are a number of factors that impact our ability to realize our deferred tax assets. Valuation allowances are provided on deferred tax assets in Nevada, Mexico, and certain Canadian jurisdictions. For additional information, please see risk factors Our accounting and other estimates may be imprecise and Our ability to recognize the benefits of deferred tax assets related to net operating loss carryforwards and other items is dependent on future cash flows and taxable incomein Item 1A - Risk Factors in our 2023 Form 10-K.

Reconciliation of Total Cost of Sales to Cash Cost, Before By-product Credits and Cash Cost, After By-product Credits (non-GAAP) and All-In Sustaining Cost, Before By-product Credits and All-In Sustaining Cost, After By-product Credits (non-GAAP)

The tables below present reconciliations between the most comparable GAAP measure of total cost of sales to the non-GAAP measures of (i) Cash Cost, Before By-product Credits, (ii) Cash Cost, After By-product Credits, (iii) AISC, Before By-product Credits and (iv) AISC, After By-product Credits for our operations and for the Company for the three and nine months ended September 30, 2024 and 2023.

Cash Cost, After By-product Credits, per Ounce and AISC, After By-product Credits, per Ounce are measures developed by precious metals companies (including the Silver Institute and the World Gold Council) in an effort to provide a uniform standard for comparison purposes. There can be no assurance, however, that these non-GAAP measures as we report them are the same as those reported by other mining companies.

Cash Cost, After By-product Credits, per Ounce is an important operating statistic that we utilize to measure each mine's operating performance. We use AISC, After By-product Credits, per Ounce as a measure of our mines' net cash flow after costs for reclamation and sustaining capital. This is similar to the Cash Cost, After By-product Credits, per Ounce non-GAAP measure we report, but also includes reclamation and sustaining capital costs. Current GAAP measures used in the mining industry, such as cost of goods sold, do not capture all the expenditures incurred to discover, develop and sustain silver and gold production. Cash Cost, After By-product Credits, per Ounce and AISC, After By-product Credits, per Ounce also allow us to benchmark the performance of each of our mines versus those of our competitors. As a silver and gold mining company, we also use these statistics on an aggregate basis - aggregating the Greens Creek and Lucky Friday mines to compare our performance with that of other silver mining companies. Similarly, these statistics are useful in identifying acquisition and investment opportunities as they provide a common tool for measuring the financial performance of other mines with varying geologic, metallurgical and operating characteristics.

We have not disclosed cost per ounce statistics for the Keno Hill operation as it is in the production ramp-up phase and has not met our definition of commercial production. See above "Consolidated Results of Operations" for our definition of commercial production. Determination of when those criteria have been met requires the use of judgment, and our definition of commercial production may differ from that of other mining companies.

Cash Cost, Before By-product Credits and AISC, Before By-product Credits include all direct and indirect operating cash costs related directly to the physical activities of producing metals, including mining, processing and other plant costs, third-party refining expense, on-site general and administrative costs, royalties and mining production taxes. AISC, Before By-product Credits for each mine also includes reclamation and sustaining capital costs. AISC, Before By-product Credits for our consolidated silver properties also includes corporate costs for general and administrative expense and sustaining capital costs. By-product credits include revenues earned from all metals other than the primary metal produced at each unit. As depicted in the tables below, by-product credits comprise an essential element of our silver unit cost structure, distinguishing our silver operations due to the polymetallic nature of their orebodies.

In addition to the uses described above, Cash Cost, After By-product Credits, per Ounce and AISC, After By-product Credits, per Ounce provide management and investors an indication of operating cash flow, after consideration of the average price received from production. We also use these measurements for the comparative monitoring of performance of our mining operations period-to-period from a cash flow perspective. We currently do not report Cash Cost, After By-product Credits, per Silver Ounce and AISC, After By-product Credits, per Silver Ounce for our Keno Hill operation as it is in the ramp-up phase of production and accordingly it is excluded from our consolidated Cash Cost, After By-product Credits, per Silver Ounce and AISC, After By-product Credits, per Silver Ounce.

Casa Berardi reports Cash Cost, After By-product Credits, per Gold Ounce and AISC, After By-product Credits, per Gold Ounce for the production of gold, their primary product, and by-product revenues earned from silver, which is a by-product at Casa Berardi. Only costs and ounces produced relating to units with the same primary product are combined to represent Cash Cost, After By-product Credits, per Ounce and AISC, After By-product Credits, per Ounce. Thus, the gold produced at Casa Berardi is not included as a by-product credit when calculating Cash Cost, After By-product Credits, per Silver Ounce and AISC, After By-product Credits, per Silver Ounce for the total of Greens Creek and Lucky Friday, our combined silver properties. Similarly, the silver produced at our other three units is not included as a by-product credit when calculating the gold metrics for Casa Berardi.

(1)

Includes all direct and indirect operating costs related to the physical activities of producing metals, including mining, processing and other plant costs, third-party refining and marketing expense, on-site general and administrative costs and royalties, before by-product revenues earned from all metals other than the primary metal produced at each operation. AISC, Before By-product Credits also includes reclamation and sustaining capital costs.

(2)

AISC, Before By-product Credits for our consolidated silver properties includes corporate costs for general and administrative expense and sustaining capital.

(3)

Lucky Friday operations were suspended in August 2023 following the underground fire in the #2 shaft secondary egress and resumed on January 9, 2024. The portion of cash costs, sustaining costs, by-product credits, and silver production incurred during the suspension period are excluded from the calculation of total cost of sales, Cash Cost, Before By-product Credits, Cash Cost, After By-product Credits, AISC, Before By-product Credits, and AISC, After By-product Credits.

(4)

Other includes $6.8 million and $14.3 million of total cost of sales for the three and nine months ended September 30, 2024, respectively, related to our environmental remediation services business. For the three and nine months ended September 30, 2023, Other includes total cost of sales of $0.9 million and $2.7 million, respectively, related to our environmental remediation services business and Nevada operations.

(5)

During the nine months ended September 30, 2023, the Company completed the necessary studies to conclude usage of the F-160 pit as a tailings storage facility after mining is complete. As a result, a portion of the mining costs have been excluded from Cash Cost, Before By-product Credits and AISC, Before By-product Credits.

(6)

Keno Hill is in the ramp-up phase of production and is excluded from the calculation of Cash Cost, Before By-product Credits, Cash Cost, After By-product Credits, AISC, Before By-product Credits, and AISC, After By-product Credits.