Lucky Friday Mullan, Idaho

Lucky Friday is a deep underground silver, lead, and zinc mine located in the Coeur d’Alene Mining District in northern Idaho. The mine began operating in 1942 and celebrated its 75th anniversary in 2017. Thanks to the #4 Shaft project which is now complete and operational, the mine is expected to have another 20-30 years of mine life. Lucky Friday is located one mile east of Mullan, Idaho, and is adjacent to U.S. Interstate 90.

In 2017, the mine produced 838,658 ounces of silver at a cash cost, after by-product credits, per silver ounce of $5.81 (a non GAAP measure) (1).

The union members at Lucky Friday have been on strike since March 13, 2017. In 2018, limited silver and lead production is being performed by salaried staff.

(1) Cash cost, after of by-product credits, per silver ounce represents a non-GAAP measurement, a reconciliation of which to cost of sales and other direct production costs and depreciation, depletion and amortization (GAAP) can be found in the legal page of this website.

Map - Lucky Friday

Learn more about the current Lucky Friday Labor Negotiations.

Overview & History

The Lucky Friday mine is a deep underground silver, lead, and zinc mine located in the Coeur d’Alene Mining District in northern Idaho. Hecla now controls 100% of the Gold Hunter deposit, also known as the Lucky Friday Expansion Area, after completing acquisition from Independence Lead Mines Company in the 4th quarter of 2008.

The mine is located approximately one mile east of Mullan, in Shoshone County, North Idaho, and 55 miles east of Coeur d’Alene, Idaho, along Interstate 90 (I-90). The facility lies just north of the interstate near exit ramp 69. The Silver Shaft head frame can be easily observed from I-90 with the shaft collar approximately 70 feet above the valley floor. The Lucky Friday vein system is immediately adjacent to the Silver Shaft and the Gold Hunter deposit lies 5,000 feet northwest of the Silver Shaft.

In 2016, ore was processed at an average rate of 803 tons per day and produced 3.6 million ounces of silver.

The #4 Shaft Project, a key growth project, is now operational. Reaching 9,600 feet below the surface, the #4 Shaft is an important part of Lucky Friday’s future as it provides access to the highest-grade ore in the mine’s 75-year history and should extend the mine life for 20-30 more years. In 2017, the focus is on developing the 6500 level to connect the #4 Shaft to the orebody.

The plant has a full surface facility complete with a 1,000 tons of ore per day mill, which produces lead and zinc concentrates. These concentrates are currently shipped for treatment via truck to Teck Cominco Metals Ltd. smelter in Trail, BC, Canada. All production is by underground methods, which include both underhand and overhand mining. The coarse mill tailing is mixed with cement and used as backfill. Production is via ramps and transfers, and substantially utilizes jumbo drills, mechanized mining, and truck haulage to the Silver Shaft. Access to the underground workings is via the 18-foot diameter, concrete lined, Silver Shaft.

Geology & Mining

There have been two ore-bearing structures mined at the Lucky Friday unit. The first, mined through 2001, was the Lucky Friday vein, a fissure vein typical of many in the Coeur d’Alene Mining District. The orebody is located in the Revett Formation, which is known to provide excellent host rocks for a number of orebodies in the Coeur d’Alene Mining District. The Lucky Friday vein strikes northeasterly and dips steeply to the south with an average width of six to seven feet. Its principal ore minerals are galena and tetrahedrite with minor amounts of sphalerite and chalcopyrite. The ore occurs as a single continuous orebody in and along the Lucky Friday vein. The major part of the orebody has extended from the 1,200-foot level to and below the 6,020-foot level.

The second ore-bearing structure, known as the Lucky Friday Expansion Area, is located in the Wallace Formation. It has been mined since 1997 pursuant to an operating agreement with Silver Hunter Mining Company (“Silver Hunter”), our wholly owned subsidiary. During 1991, we discovered several mineralized structures containing some high-grade silver ores in an area known as the Gold Hunter property, approximately 5,000 feet northwest of the then existing Lucky Friday workings. This discovery led to the development of the Gold Hunter property on the 4900 level. On November 6, 2008, we, through Silver Hunter, completed the acquisition of substantially all of the assets of Independence Lead Mines Company (“Independence”), including all future interest or royalty obligations to Independence and the mining claims pertaining to the operating agreement with Hecla Limited that was assigned to Silver Hunter.

The principal mining method at the Lucky Friday unit is ramp access, cut and fill. This method utilizes rubber-tired equipment to access the veins through ramps developed outside of the orebody. Once a cut is taken along the strike of the vein, it is backfilled with cemented tailings and the next cut is accessed, either above or below, from the ramp system.

There are three main phases to the mining process: development, production, and backfilling.

development – the tunneling or accessing phase
Using plans from the geology and engineering departments, miners drive tunnels 12ft high by 12ft wide to access the various ore zones to be mined.

production – the extraction phase
The method of extraction depends upon the geological nature of the orebody involved. Some of the narrower orebodies can be extracted using conventional mining methods (slushers and jackleg drills), mining as narrow as three feet. In other, more massive orebodies, mechanized mining methods are employed using large rubber-tired equipment to mine widths of up to 20 feet.

backfilling – the replacement phase
The voids created during the production phase are filled up with a combination of mill waste (tailings) and cement. This “backfilling” process stabilizes the production voids and allows extraction of the ore beside, above, and even below the backfilled area.

Production

(years ended December 31)
2014 2015 2016 2017
Silver (ounces) 3,239,151 3,028,134 3,596,010 838,658
Lead (tons) 20,104 18,348 21,876 4,737
Zinc (tons) 8,159 8,139 10,787 2,560
Cash cost per ounce of silver, after by-product credits, ($/oz) (1) $9.44 $11.23 $8.89 $5.81
 
(footnotes)
(1) Cash cost, after by-product credits, per silver or gold ounce is a non-GAAP measurement. A reconciliation of cash cost, after by-product credits, per silver or gold ounce to cost of sales and other direct production costs and depreciation, depletion and amortization (GAAP) can be found in the legal page of this website.
Year-End Production PDF

Reserves & Resources

Information with respect to proven and probable ore reserves, measured, and inferred resources is set forth below.

(As of  December 31, 2017 unless otherwise noted)
Tons Silver Gold Lead Zinc Silver Gold Lead Zinc
(000) (oz/ton) (oz/ton) (%) (%) (000 oz) (000 oz) (Tons) (Tons)
Proven Reserves (1,2) 4,246 15.4 9.6 4.1 65,448 407,520 175,400
Probable Reserves (1,2) 1,387 11.4 7.6 3.7 15,815 104,720 50,640
Proven and Probable Reserves 5,632 14.4 9.1 4.0 81,264 512,240 226,030
Measured Resources (3,4) 7,371 7.6 4.9 2.7 55,947 361,590 200,280
Indicated Resources (3,4) 2,344 8.2 5.3 2.5 19,202 123,120 58,160
M&I Resources 9,715 7.7 5.0 2.7 75,148 484,700 258,430
Inferred Resources (3,5) 2,820 8.7 6.3 2.7 24,646 178,970 75,270
 
(footnotes)
Note: All estimates are in-situ. Resources are exclusive of reserves. Totals may not represent the sum of parts due to rounding.
(1) The term “reserve” means that part of a mineral deposit that can be economically and legally extracted or produced at the time of the reserve determination. The term “economically,” as used in the definition of reserve, means that profitable extraction or production has been established or analytically demonstrated to be viable and justifiable under reasonable investment and market assumptions. The term “legally,” as used in the definition of reserve, does not imply that all permits needed for mining and processing have been obtained or that other legal issues have been completely resolved. However, for a reserve to exist, Hecla must have a justifiable expectation, based on applicable laws and regulations, that issuance of permits or resolution of legal issues necessary for mining and processing at a particular deposit will be accomplished in the ordinary course and in a timeframe consistent with Hecla’s current mine plans.
(2) Mineral reserves are based on $1,200 gold, $14.50 silver, $0.90 lead, $1.05 zinc, unless otherwise stated.
(3) Mineral resources are based on $1,350 gold, $21.00 silver, $0.95 lead, $1.10 zinc and $3.00 copper, unless otherwise stated.
(4) Measured and indicated resources from Gold Hunter and Lucky Friday vein systems are diluted and factored for expected mining recovery.
(5) Inferred resources from Gold Hunter and Lucky Friday vein systems are diluted and factored for expected mining recovery.

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 website 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.


2017 Reserves & Resources PDF

Exploration

At Lucky Friday, the 70,718 tons processed at the mill contained 875,488 ounces of silver.  Silver, zinc and lead production was replaced and reserves increased by 4%, 47% and 10%, respectively.  Lucky Friday consists of the main 30 Vein and a series of intermediate veins. Several costs, such as the former silver and hourly bonus and new base wages, which were previously accounted for in “other costs” are now being included in the production costs per ton when determining the cutoff grade for reserves and resources. The 30 Vein represents 75% of the silver, 76% of the lead and 66% of the zinc of the total reserve.  The 30 Vein reserve was extended to depth where a portion of the resource was drilled to indicated category, and reserves were increased in the area where the 30 and 40 veins merge to create a wide, high-grade zone that has higher zinc content. Due to the increased production costs, the cutoff grade increased significantly causing measured and indicated resources of silver, lead and zinc to decrease by 44%, 46% and 47%, respectively, as large segments of the intermediate veins are no longer above cutoff.  There was also a decline in inferred resources as silver, lead and zinc decreased by 28%, 28% and 14%, respectively.

Future Plans

Our goal is to access more resource to further extend the mine life at Lucky Friday. Currently, we believe only one-third of the tons and one-half of the ounces that are contained underground at Lucky Friday are in the current mine life. Hecla sees great organic growth opportunities at Lucky Friday.

#4 Shaft

The #4 Shaft project, an internal shaft at the Lucky Friday mine, is now operational and expected to provide deeper access in order to increase the mine’s production and operational life. The #4 Shaft Project, a key growth project, reaches 9,600 feet below the surface, and is an important part of Lucky Friday’s future as it provides access to the highest-grade ore in the mine’s 75-year history and should extend the mine life for 20-30 more years.