Note 1.    Basis of Preparation of Financial Statements

In the opinion of management, the accompanying unaudited interim condensed consolidated financial statements and notes to the unaudited interim condensed consolidated financial statements contain all adjustments, consisting of normal recurring items and items which are nonrecurring, necessary to present fairly, in all material respects, the financial position of Hecla Mining Company and its consolidated subsidiaries (in this report, "Hecla" or "the Company" or “we” or “our” or “us” refers to Hecla Mining Company and our subsidiaries, unless the context requires otherwise).  These unaudited interim condensed consolidated financial statements should be read in conjunction with our audited consolidated financial statements and related footnotes as set forth in our annual report filed on Form 10-K for the year ended December 31, 2017, as it may be amended from time to time.

The results of operations for the periods presented may not be indicative of those which may be expected for a full year.  The unaudited interim condensed consolidated financial statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission ("SEC").  Certain information and footnote disclosures normally included in audited financial statements prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) have been condensed or omitted pursuant to those rules and regulations, although we believe that the disclosures are adequate for the information not to be misleading.

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the financial statements, the reported amounts of revenues and expenses during the reporting period, and the disclosures of contingent liabilities.  Accordingly, ultimate results could differ materially from those estimates.     

On July 20, 2018, we completed the acquisition of Klondex Mines Ltd. ("Klondex"). The unaudited interim condensed consolidated financial statements included herein reflect our ownership of the assets previously held by Klondex as of the July 20, 2018 acquisition date.

In the third quarter of 2018, we identified errors impacting amounts reported for accumulated depreciation, depletion and amortization ("DDA") and DDA expense for our Casa Berardi unit from June 1, 2013 through June 30, 2018. Certain amounts in the condensed consolidated financial statements and notes thereto for the prior period have been revised to correct these errors. See Note 2 for more information on the errors and revisions made to amounts reported for the prior period.

Note 2. Revision of Previously Issued Financial Statements for Immaterial Misstatements

In the third quarter of 2018, we determined accumulated DDA and DDA expense at Casa Berardi, a business unit within our Hecla Quebec Inc. subsidiary, were understated for the periods from June 1, 2013 through June 30, 2018 as a result of errors in calculation from the date of acquisition of Casa Berardi as noted below:

We assessed the materiality of the effect of the errors on our prior quarterly and annual financial statements, both quantitatively and qualitatively, in accordance with the SEC’s Staff Accounting Bulletin ("SAB") No. 99, “Materiality,” and SAB No. 108, “Considering the Effects of Prior Year Misstatements when Quantifying Misstatements in Current Year Financial Statements,” and concluded the errors were not material to any of our previously issued financial statements. Consequently, we will correct these errors prospectively and revise our financial statements when the consolidated balance sheets, statements of operations and comprehensive income and cash flows for such prior periods are included in future filings (the "Revisions"). The Revisions had no net impact on our sales or net cash provided by operating activities for any period presented.

The following tables present a summary of the impact, by financial statement line item, of the Revisions for the three months ended March 31, 2017,  June 30, 2017 and September 30, 2017, the six months ended June 30, 2017, the nine months ended September 30, 2017, as of and for the year ended December 31, 2017, and for the year ended December 31, 2016: 

Note 3.    Investments

Our current investments, which are classified as "available for sale" and consist of bonds having maturities of greater than 90 days were $33.8 million at December 31, 2017. We held no such investments as of September 30, 2018. During the first nine months of 2018 and 2017, we had purchases of such investments of $31.2 million and $35.3 million, respectively, and maturities of $64.9 million and $31.2 million, respectively. Our current investments at December 31, 2017 consisted of the following (in thousands):

At September 30, 2018 and December 31, 2017, the fair value of our non-current investments was $7.2 million and $7.6 million, respectively.  Our non-current investments consist of marketable equity securities which are carried at fair value, and are primarily classified as “available-for-sale.” The cost basis of our non-current investments was approximately $7.9 million and $5.7 million at September 30, 2018 and December 31, 2017, respectively. In the first nine months of 2018 and 2017, we acquired marketable equity securities having a cost basis of $0.8 million and $1.6 million, respectively. During the first nine months of 2018, we recognized $2.5 million in net unrealized losses in current earnings. During the first nine months of 2017, we recognized $1.5 million in net unrealized gains in other comprehensive income and $0.1 million in net unrealized losses in current earnings.

Note 4.   Income Taxes

Major components of our income tax provision (benefit) for the three and nine months ended September 30, 2018 and 2017 are as follows (in thousands):

The current income tax provisions for the three and nine months ended September 30, 2018 and 2017 vary from the amounts that would have resulted from applying the statutory income tax rate to pre-tax income due primarily to the impact of taxation in foreign jurisdictions, a valuation allowance on the majority of U.S. deferred taxes and the impact of the change in accounting method treatment of the #4 Shaft development costs in 2017.

As of September 30, 2018, we have a net deferred tax liability in the U.S. of $46.7 million, a net deferred tax liability in Canada of $118.1 million and a net deferred tax asset in Mexico of $1.9 million, for a consolidated worldwide net deferred tax liability of $162.9 million.

With the acquisition of Klondex on July 20, 2018 (see Note 14), we acquired a U.S. consolidated tax group (the "Klondex U.S. Group") that did not join the existing consolidated U.S. tax group of Hecla Mining Company and subsidiaries (“Legacy Hecla”). Under acquisition accounting, we recorded a net deferred tax liability of $50.1 million. For the three and nine months ended September 30, 2018, we recorded a tax benefit of $3.8 million on a net tax loss of $15.2 million in the Klondex U.S. group.

For Legacy Hecla, we recorded a full valuation allowance in the U.S. in December 2017 as a result of U.S. tax reform. Our circumstances at September 30, 2018 continued to support a full valuation allowance in the U.S. for Legacy Hecla. In the first quarter of 2017, we received consent from the Internal Revenue Service to permit us to take a different income tax position relating to the timing of deductions for the #4 Shaft development costs at Lucky Friday. This tax accounting method change substantially revised the timing of deductions for these costs for regular tax and Alternative Minimum Tax ("AMT") relative to our projected life of mine and projected taxable income. These timing changes caused us to revise our assessment of the ability to generate sufficient future taxable income to realize our deferred tax assets, resulting in a valuation allowance release of approximately $15 million.

Note 5.    Commitments, Contingencies and Obligations

General

We follow GAAP guidance in determining our accruals and disclosures with respect to loss contingencies, and evaluate such accruals and contingencies for each reporting period. Accordingly, estimated losses from loss contingencies are accrued by a charge to income when information available prior to issuance of the financial statements indicates that it is probable that a liability could be incurred and the amount of the loss can be reasonably estimated. Legal expenses associated with the contingency are expensed as incurred. If a loss contingency is not probable or reasonably estimable, disclosure of the loss contingency is made in the financial statements when it is at least reasonably possible that a material loss could be incurred.

Rio Grande Silver Guaranty

Our wholly-owned subsidiary, Rio Grande Silver Inc. (“Rio”), is party to a joint venture with Emerald Mining & Leasing, LLC (“EML”) and certain other parties with respect to a land package in the Creede Mining District of Colorado that is adjacent to other land held by Rio. Rio holds a 70% interest in the joint venture. In connection with the joint venture, we are required to guarantee certain environmental remediation-related obligations of EML to a third party up to a maximum liability to us of $2.5 million. As of September 30, 2018, we have not been required to make any payments pursuant to the guaranty. We may be required to make payments in the future, limited to the $2.5 million maximum liability, should EML fail to meet its obligations to the third party. However, to the extent that any payments are made by us under the guaranty, EML, in addition to other parties, has jointly and severally agreed to reimburse and indemnify us for any such payments. We have not recorded a liability relating to the guaranty as of September 30, 2018.

Lucky Friday Water Permit Matters

In December 2013, the EPA issued to Hecla Limited a request for information under Section 308 of the Clean Water Act directing Hecla Limited to undertake a comprehensive groundwater investigation of Lucky Friday’s tailings pond no. 3 to evaluate whether the pond is causing the discharge of pollutants via seepage to groundwater that is discharging to surface water. We completed the investigation mandated by the EPA and submitted a draft report to the agency in December 2015. We are waiting for the EPA’s response and we cannot predict what further action, if any, the agency may take.

Hecla Limited strives to maintain its water discharges at the Lucky Friday unit in full compliance with its permits and applicable laws; however, we cannot provide assurance that in the future it will be able to fully comply with the permit limits and other regulatory requirements regarding water management.

Johnny M Mine Area near San Mateo, McKinley County and San Mateo Creek Basin, New Mexico

In May 2011, the EPA made a formal request to Hecla Mining Company for information regarding the Johnny M Mine Area near San Mateo, McKinley County, New Mexico, and asserted that Hecla Mining Company may be responsible under the Comprehensive Environmental Response, Compensation and Liability Act ("CERCLA") for environmental remediation and past costs the EPA has incurred at the site. Mining at the Johnny M was conducted for a limited period of time by a predecessor of our subsidiary, Hecla Limited. In August 2012, Hecla Limited and the EPA entered into a Settlement Agreement and Administrative Order on Consent for Removal Action (“Consent Order”), pursuant to which Hecla Limited agreed to pay (i) $1.1 million to the EPA for its past response costs at the site and (ii) any future response costs at the site under the Consent Order, in exchange for a covenant not to sue by the EPA. Hecla Limited paid the $1.1 million to the EPA for its past response costs and in December 2014, submitted to EPA the Engineering Evaluation and Cost Analysis (“EE/CA”) for the site. The EE/CA evaluates three alternative response actions: 1) no action, 2) off-site disposal, and 3) on-site disposal. The range in estimated costs of these alternatives is $0 to $221 million. In the EE/CA, Hecla Limited recommended that EPA approve on-site disposal, which is currently estimated to cost $5.6 million, on the basis that it is the most appropriate response action under CERCLA. In June 2015, the EPA approved the EE/CA, with a few minor conditions. The EPA still needs to publish the EE/CA for public notice and comment, and the agency will not make a final decision on the appropriate response action until the public comment process is complete. It is anticipated that Hecla Limited will implement the response action selected by the EPA pursuant to an amendment to the Consent Order or a new order. Based on the foregoing, we believe it is probable that Hecla Limited will incur a liability for remediation at the site. In the fourth quarter of 2014, we accrued $5.6 million, which continues to be our best estimate of that liability as of the date of this report. There can be no assurance that Hecla Limited’s liability will not be more than $5.6 million, or that its ultimate liability will not have a material adverse effect on Hecla Limited’s or our results of operations or financial position.

The Johnny M Mine is in an area known as the San Mateo Creek Basin (“SMCB”), which is an approximately 321 square mile area in New Mexico that contains numerous legacy uranium mines and mills. The EPA is considering listing the entire SMCB on CERCLA’s National Priorities List in order to address perceived groundwater issues within the SMCB. The EE/CA discussed above relates primarily to contaminated rock and soil, not groundwater. In the event that the SMCB is listed as a Superfund site, or for other reasons, it is possible that Hecla Limited’s liability at the Johnny M Site, as well as any other sites within the SMCB at which predecessor companies of Hecla Limited may have been involved, will be greater than our current accrual of $5.6 million due to the increased scope of required remediation.

In July 2018, the EPA informed Hecla Limited that it and several other potentially responsible parties ("PRPs") may be liable for cleanup of the site or for costs incurred by the EPA in cleaning up the site. The EPA stated it has incurred approximately $9.6 million in response costs to date. Hecla Limited cannot with reasonable certainty estimate the amount or range of liability, if any, relating to this matter because of, among other reasons, the lack of information concerning the site, including the relative contributions, if any, of contamination by the various PRPs.

Carpenter Snow Creek and Barker-Hughesville Sites in Montana

In July 2010, the EPA made a formal request to Hecla Mining Company for information regarding the Carpenter Snow Creek Superfund site located in Cascade County, Montana. The Carpenter Snow Creek site is located in a historic mining district, and in the early 1980s Hecla Limited leased 6 mining claims and performed limited exploration activities at the site. Hecla Limited terminated the mining lease in 1988.

In June 2011, the EPA informed Hecla Limited that it believes Hecla Limited, among several other viable companies, may be liable for cleanup of the site or for costs incurred by the EPA in cleaning up the site. The EPA stated in the letter that it has incurred approximately $4.5 million in response costs and estimated that total remediation costs may exceed $100 million. Hecla Limited cannot with reasonable certainty estimate the amount or range of liability, if any, relating to this matter because of, among other reasons, the lack of information concerning the site.

In February 2017, the EPA made a formal request to Hecla Mining Company for information regarding the Barker-Hughesville Mining District Superfund site located in Judith Basin and Cascade Counties, Montana. Hecla Limited submitted a response in April 2017. The Barker-Hughesville site is located in a historic mining district, and between approximately June and December 1983, Hecla Limited was party to an agreement with another mining company under which limited exploration activities occurred at or near the site.

In August 2018, the EPA informed Hecla Limited that it and several other PRPs may be liable for cleanup of the site or for costs incurred by the EPA in cleaning up the site. The EPA did not include an amount of its alleged response costs to date. Hecla Limited cannot with reasonable certainty estimate the amount or range of liability, if any, relating to this matter because of, among other reasons, the lack of information concerning past or anticipated future costs at the site and the relative contributions, if any, of contamination by the various PRPs.

Litigation Related to Klondex Acquisition

Following the announcement of our proposed acquisition of Klondex, Klondex and members of the Klondex board of directors were named as defendants in five putative stockholder class actions, brought by purported stockholders of Klondex, challenging the proposed merger. The lawsuits were all filed in the United States District Court for the District of Nevada, but only three cases remain, and they are captioned: Gunderson v. Klondex Mines Ltd., et al., No. 3:18-cv-00256 (D. Nev. May 31, 2018); Nelson Baker v. Klondex Mines Ltd., et al., No. 3:18-cv-00288 (D. Nev. June 15, 2018); and Lawson v. Klondex Mines Ltd., et al., No. 3:18-cv-00284 (D. Nev. June 15, 2018). The Gunderson complaint also named Hecla Mining Company and our subsidiary now known as Klondex Mines Unlimited Liability Company (“Merger Sub”) as defendants. The other two lawsuits were subsequently dismissed.

The plaintiffs generally claim that Klondex issued a proxy statement that included misstatements or omissions, in violation of sections 14(a) and 20(a) of the Securities Exchange Act of 1934, as amended. The Gunderson complaint also asserts a claim that the individual members of the Klondex board of directors breached their fiduciary duties of care, loyalty and good faith by authorizing the merger with Hecla for what the plaintiff asserts is inadequate consideration, an inadequate process, and with inadequate disclosures. The plaintiffs seek, among other things, to enjoin the merger, rescind the transaction or obtain rescissory damages if the merger is consummated, and recover attorneys’ fees and costs.

On September 21, 2018, Plaintiffs Baker and Lawson each filed motions to consolidate the remaining cases and be appointed lead plaintiff.

Although it is not possible to predict the outcome of litigation matters with certainty, each of Klondex, its directors, Hecla and Merger Sub believe that each of the lawsuits are without merit, and the parties intend to vigorously defend against all claims asserted.

In addition, on September 11, 2018, a lawsuit was filed in the Ontario (Canada) Superior Court of Justice by Waterton Nevada Splitter LLC against Hecla Mining Company, our subsidiary Klondex Mines Unlimited Liability Company and Havilah Mining Corporation, an entity that was formed to own the Canadian assets of Klondex that we did not acquire as part of the Klondex acquisition in July 2018, and of which we own approximately 13%. The lawsuit alleges that Hecla and Havilah are in breach of contract in connection with the issuance to Waterton of warrants to purchase Hecla common stock and Havilah common shares to replace warrants to purchase Klondex common shares that Waterton owned prior to the July 2018 acquisition. The lawsuit claims Hecla and Havilah issued warrants to Waterton valued at $3.7 million but that Waterton was entitled to warrants valued at $8.9 million. We believe the lawsuit is without merit and will vigorously defend it.

Debt

On April 12, 2013, we completed an offering of $500 million aggregate principal amount of 6.875% Senior Notes due 2021 ("Senior Notes"). The net proceeds from the offering of the Senior Notes were used to partially fund the acquisition of Aurizon Mines Ltd. ("Aurizon") and for general corporate purposes, including expenses related to the Aurizon acquisition. Through the acquisition of Aurizon, we acquired our Casa Berardi mine and other interests in Quebec, Canada. In 2014, we completed additional issuances of our Senior Notes in the aggregate principal amount of $6.5 million, which were contributed to one of our pension plans to satisfy the funding requirement for 2014. Interest on the Senior Notes is payable on May 1 and November 1 of each year, commencing November 1, 2013.

On March 5, 2018, we entered into a note purchase agreement pursuant to which we issued CAD$40 million (approximately USD$30.8 million at the time of the transaction) in aggregate principal amount of our Series 2018-A Senior Notes due May 1, 2021 (the “Notes”) to Ressources Québec, a subsidiary of Investissment Québec, a financing arm of the Québec government. The Notes were issued at a discount of 0.58%, and bear interest at a rate of 4.68% per year, payable on May 1 and November 1 of each year, commencing May 1, 2018. The Notes are senior and unsecured and are pari passu in all material respects with the Senior Notes, including with respect to guarantees of the Notes by certain of our subsidiaries. The net proceeds from the Notes are required to be used for development and expansion of our Casa Berardi mine.

See Note 10 for more information.

Other Commitments

Our contractual obligations as of September 30, 2018 included approximately $1.6 million for various costs. In addition, our open purchase orders at September 30, 2018 included approximately $0.4 million, $2.0 million, $14.2 million and $5.3 million for various capital and non-capital items at the Lucky Friday, Casa Berardi, Greens Creek and Nevada Operations units, respectively. We also have total commitments of approximately $15.7 million relating to scheduled payments on capital leases, including interest, primarily for equipment at our Greens Creek, Lucky Friday, Casa Berardi and Nevada Operations units (see Note 10 for more information). As part of our ongoing business and operations, we are required to provide surety bonds, bank letters of credit, and restricted deposits for various purposes, including financial support for environmental reclamation obligations and workers compensation programs. As of September 30, 2018, we had surety bonds totaling $181.6 million in place as financial support for future reclamation and closure costs, self-insurance, and employee benefit plans. The obligations associated with these instruments are generally related to performance requirements that we address through ongoing operations. As the requirements are met, the beneficiary of the associated instruments cancels or returns the instrument to the issuing entity. Certain of these instruments are associated with operating sites with long-lived assets and will remain outstanding until closure of the sites. We believe we are in compliance with all applicable bonding requirements and will be able to satisfy future bonding requirements as they arise.

Other Contingencies

We also have certain other contingencies resulting from litigation, claims, EPA investigations, and other commitments and are subject to a variety of environmental and safety laws and regulations incident to the ordinary course of business. We currently have no basis to conclude that any or all of such contingencies will materially affect our financial position, results of operations or cash flows. However, in the future, there may be changes to these contingencies, or additional contingencies may occur, any of which might result in an accrual or a change in current accruals recorded by us, and there can be no assurance that their ultimate disposition will not have a material adverse effect on our financial position, results of operations or cash flows.

Note 6.    (Loss) earnings Per Common Share

We are authorized to issue 750,000,000 shares of common stock, $0.25 par value per share. At September 30, 2018, there were 485,136,257 shares of our common stock issued and 5,226,791 shares issued and held in treasury, for a net of 479,909,466 shares outstanding. Basic and diluted loss per common share, after preferred dividends, was $(0.05) and $(0.01) for the three- and nine-month periods ended September 30, 2018, respectively. Basic and diluted income per common share, after preferred dividends, was $0.00 and $0.00 for the three- and nine-month periods ended September 30, 2017, respectively.

Diluted (loss) income per share for the three and nine months ended September 30, 2018 and 2017 excludes the potential effects of outstanding shares of our convertible preferred stock, as their conversion would have no effect on the calculation of dilutive shares.

For the three-month and nine-month periods ended September 30, 2018, all restricted share units, deferred shares and warrants were excluded from the computation of diluted loss per share, as our reported loss for that period would cause them to have no effect on the calculation of loss per share. For the three-month and nine-month periods ended September 30, 2017, the calculation of diluted income per share included dilutive (i) restricted stock units that were unvested or which vested in the respective period of 901,047 and 1,857,555, respectively, and (ii) deferred shares of 1,509,159 for each period. There were no warrants outstanding during the three-month and nine-month periods ended September 30, 2017.

Note 7.    Business Segments and Sales of Products

We discover, acquire, develop, produce, and market concentrates and doré containing silver, gold, lead and zinc. We are currently organized and managed in five reporting segments: the Greens Creek unit, the Lucky Friday unit, the Casa Berardi unit, the San Sebastian unit and the Nevada Operations unit. The Nevada Operations unit was added as a result of our acquisition of Klondex in July 2018 (see Note 14 for more information).

General corporate activities not associated with operating units and their various exploration activities, as well as discontinued operations and idle properties, are presented as “other.”  Interest expense, interest income and income taxes are considered general corporate items, and are not allocated to our segments.

The following tables present information about our reportable segments for the three and nine months ended September 30, 2018 and 2017 (in thousands):

The following table presents identifiable assets by reportable segment as of September 30, 2018 and December 31, 2017 (in thousands):

Our products consist of both metal concentrates, which we sell to custom smelters and brokers, and unrefined bullion bars (doré), which may be sold as doré or further refined before sale to precious metals traders. Revenue is recognized upon the completion of the performance obligations and transfer of control of the product to the customer.

For sales of metals from refined doré, the performance obligation is met and revenue is recognized at the time of transfer of control of the agreed-upon metal quantities to the customer by the refiner, and the transaction price is known at that time. For sales of doré, the performance obligation is met, the transaction price is known, and revenue is recognized at the time of transfer of title and control of the doré containing the agreed-upon metal quantities to the customer. Refining, selling and shipping costs related to sales of doré and metals from doré are recorded to cost of sales as incurred.

For concentrate sales, which we currently have at our Greens Creek and Lucky Friday units, the performance obligation is met, the transaction price can be reasonably estimated, and revenue is recognized generally at the time of shipment. Concentrates sold at our Lucky Friday unit typically leave the mine and are received by the customer within the same day. However, there is a period of time between shipment of concentrates from our Greens Creek unit and their physical receipt by the customer, and judgment is required in determining when control has been transferred to the customer for those shipments. We have determined the performance obligation is met and title is transferred to the customer upon shipment of concentrate parcels from Greens Creek because, at that time, 1) legal title is transferred to the customer, 2) the customer has accepted the parcel and obtained the ability to realize all of the benefits from the product, 3) the concentrate content specifications are known, have been communicated to the customer, and the customer has the significant risks and rewards of ownership of it, 4) it is very unlikely a concentrate parcel from Greens Creek will be rejected by a customer upon physical receipt, and 5) we have the right to payment for the parcel.

Judgment is also required in identifying the performance obligations for our concentrate sales. Most of our concentrate sales involve “frame contracts” with smelters that can cover multiple years and specify certain terms under which individual parcels of concentrates are sold. However, some terms are not specified in the frame contracts and/or can be renegotiated as part of annual amendments to the frame contract. We have determined parcel shipments represent individual performance obligations satisfied at a point in time when control of the shipment is transferred to the customer.

The consideration we receive for our concentrate sales fluctuates due to changes in metals prices between the time of shipment and final settlement with the customer. However, we are able to reasonably estimate the transaction price for the concentrate sales at the time of shipment using forward prices for the month of settlement, and previously recorded sales and accounts receivable are adjusted to estimated settlement metals prices until final settlement with the customer. Also, it is unlikely a significant reversal of revenue for any one concentrate parcel will occur. As such, we use the expected value method to price the parcels until the final settlement date occurs, at which time the final transaction price is known. At September 30, 2018, metals contained in concentrates and exposed to future price changes totaled 1.2 million ounces of silver, 5,734 ounces of gold, 7,277 tons of zinc, and 2,447 tons of lead.  However, as discussed in Note 12, we seek to mitigate the risk of negative price adjustments by using financially-settled forward contracts for some of our sales.

Sales and accounts receivable for concentrate shipments are recorded net of charges for treatment, refining, smelting losses, and other charges negotiated by us with the customers, which represent components of the transaction price. Charges are estimated by us upon shipment of concentrates based on contractual terms, and actual charges typically do not vary materially from our estimates. Costs charged by customers include fixed treatment and refining costs per ton of concentrate and may include price escalators which allow the customers to participate in the increase of lead and zinc prices above a negotiated baseline. Costs for shipping concentrates to customers are recorded to cost of sales as incurred.

Sales of metal concentrates and metal products are made principally to custom smelters, brokers and metals traders. The percentage of sales contributed by each segment is reflected in the following table:

Sales of products by metal for the three- and nine-month periods ended September 30, 2018 and 2017 were as follows (in thousands):

The following is sales information by geographic area based on the location of smelters and brokers (for concentrate shipments) and location of parent companies (for doré sales to metals traders) for the three- and nine-month periods ended September 30, 2018 and 2017 (in thousands):

Sales by significant product type for the three- and nine-month periods ended September 30, 2018 and 2017 were as follows (in thousands):

Sales of products for the three- and nine-month periods ended September 30, 2018 included net gains of $5.0 million and $8.3 million, respectively, on financially-settled forward contracts for silver, gold, lead and zinc contained in our concentrate sales. Sales of products for the three- and nine-month periods ended September 30, 2017 included net losses of $0.6 million and $3.9 million, respectively, on the forward contracts. See Note 12 for more information.

Sales of products to significant customers as a percentage of total sales were as follows for the three- and nine-month periods ended September 30, 2018 and 2017:

Our trade accounts receivable balance related to contracts with customers was $12.9 million at September 30, 2018 and 2017 and $14.8 million at December 31, 2017, and included no allowance for doubtful accounts.

We have determined our contracts do not include a significant financing component. For doré sales and sales of metal from doré, payment is received at the time the performance obligation is satisfied. The amount of consideration for concentrate sales is variable, and we receive payment for a significant portion of the estimated value of concentrate parcels within a relatively short period of time after the performance obligation is satisfied.

We do not incur significant costs to obtain contracts, nor costs to fulfill contracts which are not addressed by other accounting standards. Therefore, we have not recognized an asset for such costs as of September 30, 2018 or December 31, 2017.

The sales and income (loss) from operations amounts reported above include results from our Lucky Friday segment. The Lucky Friday mine is our only operation where some of our employees are subject to a collective bargaining agreement, and the most recent agreement expired on April 30, 2016. On February 19, 2017, the unionized employees voted against our contract offer, and on March 13, 2017 went on strike and have been on strike since that time. Production at Lucky Friday was suspended from the start of the strike until July 2017, when limited production resumed. For the first nine months of 2018 and 2017, suspension costs not related to production of $13.5 million and $11.5 million, respectively, along with $3.7 million and $2.9 million, respectively, in non-cash depreciation expense, are reported in a separate line item on our consolidated statements of operations. We cannot predict how long the strike will last or whether an agreement will be reached. As a result of the strike or other related events, operations at Lucky Friday could continue to be disrupted, which could adversely affect our financial condition and results of operations. If the strike continues for a further extended period or it is determined an eventual resolution is unlikely, it may be appropriate in the future to review the carrying value of properties, plants, equipment and mineral interests at Lucky Friday. Under such review, if estimated undiscounted cash flows from Lucky Friday were less than its carrying value, an impairment loss would be recognized for the difference between the carrying value and the estimated fair value. The carrying value of properties, plants, equipment and mineral interests at Lucky Friday as of September 30, 2018 was approximately $428.8 million. However, Lucky Friday has significant identified reserves and mineralized material and a current estimated mine life of approximately 22 years.

On April 30, 2018, we settled with the National Labor Relations Board ("NLRB") an unfair labor practice claim made by the union. As part of the settlement, Hecla Limited rescinded its last, best and final contract offer implemented in March 2017. We do not believe the settlement with the NLRB will resolve any of the key differences in the ongoing labor dispute. On May 4, 2018, we gave notice to the union that the parties to the labor dispute are at impasse, and implemented portions of our revised final offer presented in December 2017.

Note 8.   Employee Benefit Plans

We sponsor defined benefit pension plans covering substantially all U.S. employees.  Net periodic pension cost for the plans consisted of the following for the three and nine months ended September 30, 2018 and 2017 (in thousands):

For the three- and nine-month periods ended September 30, 2018, the service cost component of net periodic pension cost is included in the same line items of our condensed consolidated financial statements as other employee compensation costs, and the net expense of $0.7 million and $2.1 million, respectively, related to all other components of net periodic pension cost is included in other (expense) income on our condensed consolidated statements of operations and comprehensive income (loss). For the three- and nine-month periods ended September 30, 2017, all components of net periodic pension cost are included in the same line items of our condensed consolidated financial statements as other employee compensation costs.

In April 2018 and July 2018, we made cash contributions of  $1.3 million and $1.2 million, respectively, to our defined benefit plans. In September 2018 we contributed $5.5 million in shares of our common stock. We are not required to make additional contributions to our defined benefit plans in 2018. We expect to contribute approximately $0.5 illion to our unfunded supplemental executive retirement plan during 2018.

Note 9.    Shareholders’ Equity

Stock-based Compensation Plans

We periodically grant restricted stock unit awards, performance-based share awards and shares of common stock to our employees and directors. We measure compensation cost for restricted stock units and stock grants at the closing price of our stock at the time of grant. We measure compensation cost for performance-based grants using a Monte Carlo simulation to estimate their value at grant date. Restricted stock unit and performance-based share grants vest after a specified period with compensation cost amortized over that period. Although we have no current plans to issue stock options, we may do so in the future.

In March 2018, the Board of Directors granted 1,237,369 shares of common stock to employees for payment of long-term incentive compensation for the period ended December 31, 2017. The shares were distributed in March 2018, and $4.9 million in expense related to the stock awards was recognized in the periods prior to March 31, 2018.

In June and August 2018, the Board of Directors granted the following restricted stock unit awards to employees resulting in a total expense of $7.0 million:

An expense of $2.5 million related to the unit awards discussed above vesting in 2019 will be recognized on a straight-line basis over the twelve months following the date of the award. An expense of $2.4 million related to the unit awards discussed above vesting in 2020 will be recognized on a straight-line basis over the twenty-four months following the date of the award. An expense of $2.2 million related to the unit awards discussed above vesting in 2021 will be recognized on a straight-line basis over the thirty-six-month period following the date of the award.

In June 2018, the Board of Directors granted performance-based share awards to certain executive employees. The value of the awards will be based on the ranking of the market performance of our common stock relative to the performance of the common stock of a group of peer companies over the three-year measurement period ending December 31, 2020. The number of shares to be issued will be based on the value of the awards divided by the share price at grant date. The expense related to the performance-based awards will be recognized on a straight-line base over the thirty months following the date of the award.

Stock-based compensation expense for restricted stock unit and performance-based grants to employees and shares issued to nonemployee directors recorded in the first nine months of 2018 totaled $4.7 million, compared to $4.9 million in the same period last year.

In connection with the vesting of restricted stock units and other stock grants, employees have in the past, at their election and when permitted by us, chosen to satisfy their minimum tax withholding obligations through net share settlement, pursuant to which the Company withholds the number of shares necessary to satisfy such withholding obligations and pays the obligations in cash.  As a result, in the first nine months of 2018 we withheld 697,341 shares valued at approximately $2.7 million, or approximately $3.86 per share. In the first nine months of 2017 we withheld 588,240 shares valued at approximately $3.0 million, or approximately $5.09 per share.

Common Stock Dividends

In September 2011 and February 2012, our Board of Directors adopted a common stock dividend policy that has two components: (1) a dividend that links the amount of dividends on our common stock to our average quarterly realized silver price in the preceding quarter, and (2) a minimum annual dividend of $0.01 per share of common stock, in each case, payable quarterly, if and when declared. For illustrative purposes only, the table below summarizes potential per share dividend amounts at different quarterly average realized price levels according to the first component of the policy:

On November 6, 2018, our Board of Directors declared a common stock dividend, pursuant to the minimum annual dividend component of the policy described above, of $0.0025 per share, for a total dividend of approximately $1.2 million payable in December 2018. Because the average realized silver price for the third quarter of 2018 was $14.68 per ounce, below the minimum threshold of $30 according to the policy, no silver-price-linked component was declared or paid. The declaration and payment of common stock dividends is at the sole discretion of our Board of Directors.

At-The-Market Equity Distribution Agreement

Pursuant to an equity distribution agreement dated February 23, 2016, we may issue and sell shares of our common stock from time to time through ordinary broker transactions having an aggregate offering price of up to $75 million, with the net proceeds available for general corporate purposes. The terms of sales transactions under the agreement, including trading day(s), number of shares sold in the aggregate, number of shares sold per trading day, and the floor selling price per share, are proposed by us to the sales agent. Whether or not we engage in sales from time to time may depend on a variety of factors, including share price, our cash resources, customary black-out restrictions, and whether we have any material inside information. The agreement can be terminated by us at any time. The shares issued under the equity distribution agreement are registered under the Securities Act of 1933, as amended, pursuant to our shelf registration statement on Form S-3, which was filed with the SEC on February 23, 2016. As of September 30, 2018, we had sold 5,634,758 shares under the agreement for total proceeds of approximately $20.8 million, net of commissions of approximately $0.5 million. We sold 1,025,911 shares under the agreement during the third quarter of 2018 for total proceeds of $3.1 million, net of commissions of approximately $0.1 million.

Common Stock Repurchase Program

On May 8, 2012, we announced that our Board of Directors approved a stock repurchase program.  Under the program, we are authorized to repurchase up to 20 million shares of our outstanding common stock from time to time in open market or privately negotiated transactions, depending on prevailing market conditions and other factors.  The repurchase program may be modified, suspended or discontinued by us at any time. Whether or not we engage in repurchases from time to time may depend on a variety of factors, including not only price and cash resources, but customary black-out restrictions, whether we have any material inside information, limitations on share repurchases or cash usage that may be imposed by our credit agreement or in connection with issuances of securities, alternative uses for cash, applicable law, and other investment opportunities from time to time. As of September 30, 2018, 934,100 shares have been purchased at an average price of $3.99 per share, leaving approximately 19.1 million shares that may yet be purchased under the program. The closing price of our common stock at November 6, 2018, was $2.49 per share.

Warrants

As discussed in Note 14, we issued 4,136,000 warrants to purchase one share of our common stock to holders of warrants to purchase Klondex common stock under the terms of the Klondex acquisition, and all of the warrants were outstanding as of September 30, 2018. 2,068,000 of the warrants have an exercise price of $8.02 and expire in April 2032. 2,068,000 of the warrants have an exercise price of $1.57 and expire in February 2029.

Note 10.    Debt, Credit Facility and Capital Leases

Senior Notes

On April 12, 2013, we completed an offering of $500 million in aggregate principal amount of our Senior Notes due May 1, 2021 in a private placement conducted pursuant to Rule 144A and Regulation S under the Securities Act of 1933, as amended, and in 2014, an additional $6.5 million aggregate principal amount of the Senior Notes were issued to one of our pension plans. The Senior Notes were subsequently exchanged for substantially identical Senior Notes registered with the SEC. The Senior Notes are governed by the Indenture, dated as of April 12, 2013, as amended (the "Indenture"), among Hecla Mining Company ("Hecla") and certain of our subsidiaries and The Bank of New York Mellon Trust Company, N.A., as trustee. The net proceeds from the initial offering of the Senior Notes ($490 million) were used to partially fund the acquisition of Aurizon and for general corporate purposes, including expenses related to the Aurizon acquisition.

The Senior Notes are recorded net of a 2% initial purchaser discount totaling $10 million at the time of the April 2013 issuance and having an unamortized balance of $3.3 million as of September 30, 2018. The Senior Notes bear interest at a rate of 6.875% per year from the date of original issuance or from the most recent payment date on which interest has been paid or provided for.  Interest on the Senior Notes is payable on May 1 and November 1 of each year, commencing November 1, 2013. During the nine months ended September 30, 2018 and 2017, interest expense related to the Senior Notes and amortization of the initial purchaser discount and fees related to the issuance of the Senior Notes totaled $27.2 million and $26.3 million, respectively. The interest expense related to the Senior Notes for the nine months ended September 30, 2017 was net of $0.9 million in capitalized interest, primarily related to the #4 Shaft project at our Lucky Friday unit which was completed in January 2017. Interest expense for the nine months ended September 30, 2017 also included $1.1 million in costs related to our private offering of new Senior Notes in June 2017 and concurrent tender offer to purchase our existing Senior Notes, which were not completed.

The Senior Notes are guaranteed on a senior unsecured basis by certain of our subsidiaries (the "Guarantors").   The Senior Notes and the guarantees are, respectively, Hecla's and the Guarantors' general senior unsecured obligations and are subordinated to all of Hecla's and the Guarantors' existing and future secured debt to the extent of the assets securing that secured debt.  In addition, the Senior Notes are effectively subordinated to all of the liabilities of Hecla's subsidiaries that are not guaranteeing the Senior Notes, to the extent of the assets of those subsidiaries.