Railroad Copper-Gold Property (Bullion Copper-Gold Project; Polymetallic prospect; Nevada Bunker Hill Mines; Aladdin Claim; Blue Sky Claim; Tripoli Claim; Webfoot Claim; Mahogany Claim; Standing Elk Claim; Hoffman Claim; Mounted Ledge Claim; Bullion Claim; Cleveland Claim; Portal Claim), Railroad Mining District, Elko County, Nevada, USAi

Regional Level Types
Railroad Copper-Gold Property (Bullion Copper-Gold Project; Polymetallic prospect; Nevada Bunker Hill Mines; Aladdin Claim; Blue Sky Claim; Tripoli Claim; Webfoot Claim; Mahogany Claim; Standing Elk Claim; Hoffman Claim; Mounted Ledge Claim; Bullion Claim; Cleveland Claim; Portal Claim)	- not defined -
Railroad Mining District	Mining District
Elko County	County
Nevada	State
USA	Country

Structure: North- to northeast-trending Bunker Hill fault; E-W-trending Bald Mountain fault

Alteration: sericitization, silicification

Commodity: Ore Materials: malachite, chalcanthite, cerussite, cerargyrite, duftite, copper pitch, azurite, galena, bornite, chalcopyrite, sphalerite, chalcocite, tetrahedrite, scheelite, pyromorphite Gangue Materials: calcite, garnet, tremolite, quartz, fluorite, wollastonite, halloysite, pyrite, barite

Deposit: The ore occurs as pipe-like replacements in marbelized limestone along porphyry dikes at intersections with faults. The largest mass was 50 feet in diameter and extended vertically for 400 feet and yielded 50,000 tons of oxidized ore grading 18.2% lead, 5.4% copper, and 19 oz of silver per ton. Scheelite-bearing tactite 2-3-feet wide occurs in the Davis tunnel about 3000 feet from the portal. In some areas, chimneys of high-grade silver-lead ore occur at fissure intersections and shear zones.

Deposit type: Skarn Cu

Development: The original Bunker Hill mines were discovered in the1870s, with early ore treated in a small smelter erected at Bullion City. The mine originally opened on 7 levels with the 'low level' adit (Davis tunnel) the main access. Production continued until 1887, then ceased until 1905 when the Nevada Bunker Hill Mining Co. consolidated the area mines and 2 low level adits were begun at the new camp of Bullion, to explore the downward extension of the orebodies. The property was operated during the 1930s by the Aladdin Mines Co. The Davis tunnel was extended to a target length of 6,040 feet in 1959, in an attempt to reach a projected extension of the Standing Elk orebody but no ore was found. Later the Webfoot Adit shared the same dump and portal area and was extended to 900 feet, with several hundred feet of crosscuts. The Standing Elk has over 10,000 feet of workings, and was one of the major producers of the district, with most of the intermittent production since 1908 to its credit. The Railroad/Bullion District has seen many periods of subsequent exploration for a variety of commodities. The most recent owner is Royal Standard Minerals who in 2006 is explorijng the property as a copper-gold polymetallic prospect. At the end of 2006, RSM reported that a geologic field mapping and geophysics program was completed during October and November 2006 on the Railroad copper-skarn system. The alteration mapping and a large ground magnetics program provided very useful data in targeting future drill hole sites on the property. The geophysical interpretation of this data is underway. No drilling was completed in October and November on this property due to delays with the availability of a drill, weather and the need to complete the evaluation of the new geophysical and geologic data. The drilling program is now rescheduled for the spring of 2007.

Ore(s): Ore is localized by proximity of favorable reactive host rocks to intrusives, coupled with fault intersections.

Other Databases

Link to USGS MRDS:	10310317

Other Regions, Features and Areas containing this locality

References