Allied Nevada Gold Corp


	Geology and Mineralization The Hycroft mine is located in the Nevada basin and range geologic province on the western flank of the Kamma Mountains, straddling the county line between Humboldt and Pershing Counties, Nevada. Tertiary-to-recent, fault controlled, low sulfidation gold deposits occur over an area measuring three miles in a north-south direction and two miles in an east-west direction. Based on drilling results, mineralization extends to depths of at least 330 ft from the northwest corner of the Bay Area, to over 1,000 ft in the Brimstone deposit in the eastern portion of the Hycroft property, and over 2,000 ft in the southeastern Vortex Zone. Five major north-northeast trending, west dipping, normal fault zones broadly bound gold mineralization. The fault zones are referred to as the Central, Boneyard, Albert, Fire and East faults. The Bay Area, Central and South Central, Cut-3, and Cut-4 zones are hosted by sedimentary conglomerate and lacustrine rocks (the “Sulfur Group”) in the hanging wall of the Central fault. The Brimstone Zone is hosted within the hanging wall of the East Fault. This portion of the deposit has been highly structurally prepared by at least four phases of alteration. Gold mineralization is thought to have occurred during periods of fracture and breccia controlled chalcedony sulfide mineralization. Oxidation appears to be related to a deep, wide spread acid leaching event, and by descending supergene fluids along the East Fault. The Vortex Zone, bordering the south end of the Brimstone Zone, is hosted in rocks similar to those at Brimstone, but overprinted with extensive hydrothermal brecciation. Alteration in the Vortex Zone is primarily strong silicification capped with hydrothermal argillic and subordinate acid leach alteration. Mineralization in the Vortex Zone is thought to be related to several pulses of fracturing and hydrothermal brecciation, plus quartz and chalcedonic veining. Vortex is bounded on the east by the East Fault, and is open to the north, west, and south and at depth. The historically mined Lewis, Bay Area, Central and South Central, Cut-3, and Cut-4 zones are hosted in the Sulfur Group in the hanging wall of the Central Fault. The host rocks in these zones are silicified conglomerate rocks comprised of sedimentary and volcanic rock fragments. The Central fault provided mineralizing fluids which both altered the host rock and deposited gold and silver. Alteration ranges from strong argillic and acid leaching in the Central, Cut-3 and Cut-4 areas, to passive silicification and hot spring sinters in the Bay Area and Lewis areas.