Hecla Reports Third Quarter Drilling and Exploration Results

Hecla Reports Third Quarter Drilling and Exploration Results

New discoveries at San Sebastian

Hecla Mining Company (NYSE:HL) today provided an update on its exploration programs during the third quarter.

Third Quarter Exploration Highlights

• Drilling at San Sebastian has identified polymetallic zones similar to the Hugh Zone on the Middle and West Francine veins.
• Surface and underground drilling at Casa Berardi has expanded and refined resources to increase the size and number of the open pits and extended high-grade lenses along strike and at depth in the underground.
• Drilling of East Ore, NWW and Upper Plate zones is expected to convert resources into reserves in the upper and central part of the Greens Creek Mine.

“Exploration success continues at San Sebastian with the discovery of additional high-grade mineralization that has the potential to extend the mine life. When we restarted San Sebastian we had less than a two-year mine plan and now we see potential through 2020 and beyond. As well, new zones are emerging along both the Middle and Francine veins with similar mineralogy as the Hugh Zone, a 1.5 million ton polymetallic resource, so we see the underground sulphide deposit potentially growing to further extend mine life,” said Phillips S. Baker, Jr., President and CEO. “At Casa Berardi, the exploration confirms our view of the exploration potential we believed was possible when we acquired the property. The surface program is expanding the open pits and the underground is identifying new lenses with good grades. Finally, drilling at Greens Creek has discovered high-grade mineralization high up in the mine which could enhance Greens Creek’s already exceptional mine economics.”

San Sebastian

During the quarter, three core drills were active along the Middle, Francine and West Francine vein areas.

In-fill holes were drilled primarily along the western portion of the Middle Vein to aid stope design for underground mine development. The results of in-fill drilling are consistent with or better than those from previous drilling. These veins are narrow but show good continuity and are open to the west and at depth. Assay results from in-fill drilling this quarter include, 0.26 oz/ton gold and 54.9 oz/ton silver over 3.5 feet and 0.19 oz/ton gold and 41.3 oz/ton silver over 4.4 feet.

Some drilling of the West Middle Vein was directed toward a new zone of high-grade mineralization that is similar to the mineralization in the previously discovered Hugh Zone on the Francine Vein. Assay results from this new zone include 0.02 oz/ton gold, 9.5 oz/ton silver, 3% copper, 2% lead, and 5% zinc over 4.0 feet and 0.07 oz/ton gold, 12.0 oz/ton silver, 4% copper, 6% lead, and 9% zinc over 5.4 feet. This mineralization is located about 300 feet west and 300 feet below the new Middle Vein underground mine development. In addition to containing high-grade gold and silver, this area also has potentially recoverable quantities of copper, lead, and zinc.

On the Francine Vein, two drill holes intersected high-grade mineralization approximately 600 feet to the west of the current Hugh Zone resource area and returned 0.01 oz/ton gold, 28.5 oz/ton silver, 6% copper, 9% lead, and 14% zinc over 3.6 feet and 0.01 oz/ton gold, 19.7 oz/ton silver, 3% copper, 12% lead, and 13% zinc over 3.4 feet. More recent drilling a further 500 feet to the west intersected polymetallic veins. These recent vein intercepts suggest that the Hugh Zone resource area extends to the west, and closer to surface. Additionally, a drill hole 2,500 feet to the west of the Hugh Zone resource intersected a polymetallic vein with assay results of 0.01 oz/ton gold, 6.2 oz/ton silver, 2% copper, 3% lead, and 4% zinc over 12 feet. The vein is largely open between the most recent drilling west of the Hugh Zone and this most western intersection. Drilling continues to expand resources and evaluate deeper polymetallic targets along the Middle and Francine veins.

Recent assay results from drilling on the East Francine Vein, 0.01 oz/ton gold and 14.8 oz/ton silver over 12.8 feet, have defined a large resource approximately 1,200 feet east of existing workings. Drilling along the adjacent East Middle Vein, intersected 0.05 oz/ton gold and 7.6 oz/ton silver over 8.0 feet. These two discoveries are close together, increasing the potential for the development of a new mining area.

More complete drill assay highlights from San Sebastian can be found in Table A at the end of this release and a presentation showing drill intersection locations is available at the following: http://ir.hecla-mining.com/interactive/newlookandfeel/4130678/Hecla-Q3-2017-ExplorationUpdate.pdf.

Casa Berardi – Quebec

During the third quarter, seven underground drills were used to refine stope designs and expand reserves and resources in the 118, 123, and 124 zones. Up to four drills on surface completed both in-fill and exploration drilling to define a series of open pit areas along the Casa Berardi Fault.

At the Lower 118 Zone, drilling has confirmed the continuity of multiple mineralized lenses that extend over 1,600 feet down-plunge and remain open to depth and to the east and west of the current resources. Drilling at the lower 118 Zone returned 0.26 oz/ton gold over 19.5 feet outside the western limit of the resources and suggests there is good potential to extent high-grade resources to the west. Recent drilling returned strong mineralization including 0.21 oz/ton gold over 8.2 feet and 0.20 oz/ton gold over 10.8 feet approximately 150 feet below the current mine infrastructure.

Drilling of stacked, high-grade lenses of the 123 Zone show that mineralized lenses identified higher in the mine extend to depth and define a semi-continuous mineralized zone of over 3,000 feet down-dip and 1,600 feet of strike length. Drilling of the lower 123 Zone at the bottom of the mine show that it is open at depth and to the east and west of the current resources. Exploration drilling below the mine infrastructure intersected 0.33 oz/ton gold over 11.5 feet and 0.29 oz/ton gold over 25.6 feet showing the continuity of the mineralization down-plunge of the zone. Drilling on the western extreme of the lower 123 Zone intersected 0.32 oz/ton gold over 73.0 feet, confirming the continuation of multiple lenses to the west and below the mine infrastructure. Exploration drilling is planned for the fourth quarter to further define this western extension.

Intersections from drilling on the upper part of the 124 Zone include 0.40 oz/ton gold over 9.8 feet and 0.43 oz/ton gold over 9.5 feet, suggesting mineralization continues down from surface and is open at depth and to the west. Drilling in this area has also confirmed the high-grade nature of the crown pillar below the proposed Principal Pit. Additionally, exploration drilling from surface targeting the shallow eastern extension of the 124 Zone intersected strong mineralization, suggesting the potential for underground mining. Underground drilling of this target is planned for the fourth quarter from the 290 drift.

A series of potential pits along the Casa Berardi Fault are being investigated. Surface drilling along the northeast extension of the proposed Principal Pit area confirmed 1,200 feet of continuity to the northeast and includes an intersection of 0.24 oz/ton gold over 19.7 feet. Recent surface drilling near the Casa Berardi Fault at the 134 Zone has identified a series of high-grade, sub-parallel veins within broader intersections of 0.06 oz/ton gold over 106.0 feet and 0.07 oz/ton gold over 43.0 feet. This drilling has shown good continuity and final pit optimization studies are being completed. Deeper drilling has demonstrated that the down-plunge extensions of this mineralization, including an intersection of 0.21 oz/ton gold over 16.3 feet, will likely extend below the pit and may have potential for underground mining.

Definition drilling of the 160 Zone, including 0.10 oz/ton gold over 149.3 feet and 0.12 oz/ton gold over 29.6 feet, has confirmed the continuity and grade of the resources and is the basis for the current investigation into the viability of another open pit. Drilling the west extension of the current East Mine Crown Pillar (EMCP) pit has return 0.11 oz/ton gold over 27.1 feet and 0.09 oz/ton gold over 61.4 feet to define an extension over 650 feet to the west of the current pit outline.

Surface exploration drilling of the NW-SW Zone at the west end of the mining lease is investigating the surface pillar within 1,000 feet of surface. Drilling has intersected strong mineralization north of the Casa Berardi Fault including a broad mineralized zone of 0.09 oz/ton gold over 42.7 feet that contains an interval of 0.23 oz/ton gold over 9.8 feet. Overall, these intersections show the expansion of mineralization up-dip of the Lower Inter and South West zones to create new near-surface inferred resources. In-fill drilling in 2017 may convert a large portion of those resources to indicated category with the eventual incorporation into the life of mine plan. Exploration drilling continues to expand these mineralized zones along strike to the west. Deeper drilling from surface of the Lower Inter Zone returned 0.19 oz/ton gold over 19.7 feet along the northern contact of the Lower Inter Fault at over 2,000 feet below the surface. These deep zones of mineralization are west of current mine infrastructure and could be developed if the resources expand sufficiently.

Aggressive surface drilling programs will continue for the remainder of the year at the 124 Zone (Principal area), 134 Zone, 146/East Mine Crown Pillar, 160 Zone and South West zones to define a possible series of open pits along the Casa Berardi Fault. Underground drilling will continue to expand and refine the lower 118 and 123 zones near the bottom of the mine.

More complete drill assay highlights from Casa Berardi can be found in Table A at the end of the release and a presentation showing drill intersection locations is available at the following: http://ir.hecla-mining.com/interactive/newlookandfeel/4130678/Hecla-Q3-2017-ExplorationUpdate.pdf.

Greens Creek – Alaska

At Greens Creek, drilling in the third quarter targeted the Deep 200 South, East Ore, Gallagher and the Upper Plate zones. Exploration drilling on the Deep 200 South Zone extended the 200 South Bench mineralization south of current resource. Drilling on the East Ore, Gallagher and Upper Plate zones upgraded and expanded the known resource. Strong assay results were also received from previous drilling on the East Ore, Gallagher and Upper Plate zones.

Drilling of the East Ore Zone compares favorably to previously modeled resource estimates at higher elevations and indicate expanded resources to the south and at depth. Drilling intercepted 75.1 oz/ton silver, 0.16 oz/ton gold, 5.32% zinc and 2.67% lead over 9.5 feet in an area without previously identified resources and another exploration drill hole intercepted 11.0 oz/ton silver, 0.13 oz/ton gold, 12.8% zinc and 7.3% lead over 7.7 feet within an area of no previously identified mineralization. Aggressive drilling of the East Ore Zone is planned to continue well into 2018 with the goal of confirming reserves and expanding the known resource.

Assays received for the Upper Plate Ore Zone further upgraded the existing resource and included 75.2 oz/ton silver, 0.09 oz/ton gold, 6% zinc and 3% lead over 5.4 feet. This Upper Plate mineralization is close to underground mine infrastructure and only 300 feet below the mine portal. Drilling of the Gallagher Zone identified new mineralization between current resources and included 11.6 oz/ton silver, 0.09 oz/ton gold, 5.2% zinc and 2.5% lead over 32.3 feet.

Surface drilling was completed on targets in the Gallagher, East Ore and 5250 zones. Drilling on the Gallagher Zone intersected mineralized sheared veins and breccia intervals of up to 100 feet thick containing higher-grade intervals of 1.5 to 4 feet wide that have up to 15% zinc and 4.0 oz/ton silver. This mineralized structure appears to be the same Klaus Shear identified within the mine workings east of the Gallagher fault. The mineralized Klaus Shear now extends 1,500 feet west of the mine and over 3,000 feet north to south. Drilling successfully intercepted the main mine horizon of the 5250 Zone over 2,000 feet south of the known resource showing promising alteration at the contact. Assays from the drilling of a number of holes on the Gallagher and 5250 zones are pending.

Underground drilling for the remainder of the year will focus on the East Ore, Upper Plate, Deep 200 South and Gallagher zones.

More complete drill assay highlights from Greens Creek can be found in Table A at the end of this release and a presentation showing drill intersection locations is available at the following: http://ir.hecla-mining.com/interactive/newlookandfeel/4130678/Hecla-Q3-2017-ExplorationUpdate.pdf.

ABOUT HECLA

Founded in 1891, Hecla Mining Company (NYSE:HL) is a leading low-cost U.S. silver producer with operating mines in Alaska, Idaho and Mexico, and is a growing gold producer with an operating mine in Quebec, Canada. The Company also has exploration and pre-development properties in seven world-class silver and gold mining districts in the U.S., Canada, and Mexico, and an exploration office and investments in early-stage silver exploration projects in Canada.

Cautionary Statements Regarding Forward Looking Statements

Statements made or information provided in this news release that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995 and "forward-looking information" within the meaning of Canadian securities laws. Words such as “may”, “will”, “should”, “expects”, “intends”, “projects”, “believes”, “estimates”, “targets”, “anticipates” and similar expressions are used to identify these forward-looking statements. The material factors or assumptions used to develop such forward-looking statements or forward-looking information include that the Company’s plans for development and production will proceed as expected and will not require revision as a result of risks or uncertainties, whether known, unknown or unanticipated, to which the Company’s operations are subject.

Forward-looking statements involve a number of risks and uncertainties that could cause actual results to differ materially from those projected, anticipated, expected or implied. These risks and uncertainties include, but are not limited to, metals price volatility, volatility of metals production and costs, litigation, regulatory and environmental risks, operating risks, project development risks, political risks, labor issues, ability to raise financing and exploration risks and results. Refer to the Company's Form 10K and 10-Q reports for a more detailed discussion of factors that may impact expected future results. The Company undertakes no obligation and has no intention of updating forward-looking statements other than as may be required by law.

Cautionary Statements to Investors on Reserves and Resources

Reporting requirements in the United States for disclosure of mineral properties are governed by the SEC and included in the SEC's Securities Act Industry Guide 7, entitled “Description of Property by Issuers Engaged or to be Engaged in Significant Mining Operations” (Guide 7). However, the Company is also a “reporting issuer” under Canadian securities laws, which require estimates of mineral resources and reserves to be prepared in accordance with Canadian National Instrument 43-101 (NI 43-101). NI 43-101 requires all disclosure of estimates of potential mineral resources and reserves to be disclosed in accordance with its requirements. Such Canadian information is being included here to satisfy the Company's “public disclosure” obligations under Regulation FD of the SEC and to provide U.S. holders with ready access to information publicly available in Canada.

Reporting requirements in the United States for disclosure of mineral properties under Guide 7 and the requirements in Canada under NI 43-101 standards are substantially different. This document contains a summary of certain estimates of the Company, not only of proven and probable reserves within the meaning of Guide 7, which requires the preparation of a “final” or “bankable” feasibility study demonstrating the economic feasibility of mining and processing the mineralization using the three-year historical average price for any reserve or cash flow analysis to designate reserves and that the primary environmental analysis or report be filed with the appropriate governmental authority, but also of mineral resource and mineral reserve estimates estimated in accordance with the definitional standards of the Canadian Institute of Mining, Metallurgy and Petroleum referred to in NI 43-101. The terms “measured resources”, “indicated resources,” and “inferred resources” are Canadian mining terms as defined in accordance with NI 43-101. These terms are not defined under Guide 7 and are not normally permitted to be used in reports and registration statements filed with the SEC in the United States, except where required to be disclosed by foreign law. The term “resource” does not equate to the term “reserve”. Under Guide 7, the material described herein as “indicated resources” and “measured resources” would be characterized as “mineralized material” and is permitted to be disclosed in tonnage and grade only, not ounces. The category of “inferred resources” is not recognized by Guide 7. Investors are cautioned not to assume that any part or all of the mineral deposits in such categories will ever be converted into proven or probable reserves. “Resources” have a great amount of uncertainty as to their existence, and great uncertainty as to their economic and legal feasibility. It cannot be assumed that all or any part of such a “resource” will ever be upgraded to a higher category or will ever be economically extracted. Investors are cautioned not to assume that all or any part of a “resource” exists or is economically or legally mineable. Investors are also especially cautioned that the mere fact that such resources may be referred to in ounces of silver and/or gold, rather than in tons of mineralization and grades of silver and/or gold estimated per ton, is not an indication that such material will ever result in mined ore which is processed into commercial silver or gold.

Qualified Person (QP) Pursuant to Canadian National Instrument 43-101

Dean McDonald, PhD. P.Geo., Senior Vice President - Exploration of Hecla Mining Company, who serves as a Qualified Person under National Instrument 43-101, supervised the preparation of the scientific and technical information concerning Hecla’s mineral projects in this news release. Information regarding data verification, surveys and investigations, quality assurance program and quality control measures and a summary of sample, analytical or testing procedures for the Greens Creek Mine are contained in a technical report prepared for Hecla titled “Technical Report for the Greens Creek Mine, Juneau, Alaska, USA” effective date March 28, 2013, and for the Lucky Friday Mine are contained in a technical report prepared for Hecla titled “Technical Report on the Lucky Friday Mine Shoshone County, Idaho, USA” effective date April 2, 2014, for the Casa Berardi Mine are contained in a technical report prepared for Hecla titled "Technical Report on the Mineral Resource and Mineral Reserve Estimate for the Casa Berardi Mine, Northwestern Quebec, Canada" effective date March 31, 2014 (the "Casa Berardi Technical Report"), and for the San Sebastian Mine are contained in a technical report prepared for Hecla titled "Technical Report for the San Sebastian Ag-Au Property, Durango, Mexico" effective date September 8, 2015. Also included in these three technical reports is a description of the key assumptions, parameters and methods used to estimate mineral reserves and resources and a general discussion of the extent to which the estimates may be affected by any known environmental, permitting, legal, title, taxation, socio-political, marketing or other relevant factors. Copies of these technical reports are available under Hecla's profile on SEDAR at www.sedar.com.

Hecla Mining Company
Mike Westerlund, 800-HECLA91 (800-432-5291)
Vice President, Investor Relations
hmc-info@hecla-mining.com
www.hecla-mining.com

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