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 ore body is located in the Revett Formation, which is known to provide excellent host rocks for a number of ore bodies 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 ore body in and along the Lucky Friday vein. The major part of the ore body has extended from 1,200 feet to 6,020 feet below surface.

The second ore-bearing structure, known as the Lucky Friday Expansion Area, or Gold Hunter, 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. At approximately 4,900 feet below surface, the Gold Hunter veins are hosted in a 200-foot thick siliceous lens within the Wallace Formation that transitions to the St. Regis Formation below 5,900 feet. The veins are sub- parallel, and are numbered consecutively from the hanging wall of the favorable horizon to the footwall. The strike of the vein system is west-northwest with a dip of 85 degrees to the south. The 30 vein, which has demonstrated to contain higher silver grades, represents approximately 71% of our current proven and probable ore reserve tonnages, while the remaining 29% of our reserves are contained in various intermediate veins having lower silver grades than 30 vein. While the veins share many characteristics with the Lucky Friday vein, the Gold Hunter area possesses some mineralogical and rock mechanics differences that make it more favorable to mine at this time.

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 ore body. 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.

Ore at the Lucky Friday is processed using a conventional lead/zinc flotation flowsheet, with process control guided by a real-time, on-line analyzer. Run of mine ore is crushed in a conventional three stage crushing plant consisting of a primary jaw crusher, and a secondary crushing circuit, and tertiary cone crushing stage. Crushed ore is ground in a ball mill, and the ground slurry reports to the lead flotation circuit. The lead circuit tailings report to the zinc flotation circuit. Lead and zinc concentrates are thickened and filtered, and final concentrate products are shipped to smelters for final processing.