Base metal mineralization in the Liberty deposit consists of molybdenite (MoS2), chalcopyrite (CuFeS2), chalcocite (Cu2S), galena (PbS), sphalerite (ZnS), tetrahedrite (Cu8Sb2S7), and pyrite (FeS2). Molybdenite occurs mainly in 0.1" to 1.2"-wide quartz veins and veinlets in amounts that range from 0.1% to more than 40% by volume, typically as a selvage on vein walls. Molybdenite is also found in wider (+1.2”) quartz veins, but these are much less common in occurrence. Chalcopyrite and pyrite also are common but lesser vein/veinlet constituents. Galena, sphalerite, and lesser tetrahedrite occur with quartz in separate generations of base metal veins and veinlets that were emplaced at the end of each mineralization pulse (Shaver, 1991).

In general, molybdenum-bearing quartz veins and veinlets are more concentrated along the margins of the Hall stock, forming an irregular shell or sleeve of higher grade mineralization around a lower grade core. However, the intensity of quartz veining does not correlate directly with higher grade molybdenum – barren quartz veins are common within the deposit. Disseminated molybdenite is rare, occurring only in a 100'- to 200'- thick portion of the North Hall stock as replacements in biotite and/or plagioclase sites (Shaver, 1991). In addition to quartz, minor gangue minerals present in the veins and veinlets include fluorite, scheelite, tourmaline, gearksutite, and creedite, with siderite, dolomite, and calcite occurring as vug fillin ........

The Liberty mine project will employ conventional hard rock, open pit mining methods. Ore production to the mill is planned at 26,500 short tons per day (st/d) (9,673,000 short tons per year). The mine plan and production schedule was developed with the goal of filling the mill at the required ore rate and maximizing the project return on investment. The total material rate starts at 32 million short tons per year (Mst/y) for the first six years and then ramps up to 42 Mst/y for six years before reducing to lower levels for the last half of the mine life.

The mining bench height is 40 ft high. Drilling will be completed with 2 and later 3 rotary blast hole rigs with 75,000 lb pull down capacity. Blasted rock will be loaded into 150-ton haul trucks using 2 hydraulic shovels of 27 cubic yard capacity and 1 front-end-loader of with a 27 cubic yard bucket.

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