The Jarbidge district is in northern Elko County about 60 miles west of the Utah State line and 5 miles south of the Idaho State line.
Gold ore was first discovered in 1904 (Schrader, 1912, p. 15), but the major discovery was not until 1909. A rush to the area took place the following year, and the town of Jarbidge was soon founded.
Production totaled about 217,800 ounces from 1911 through 1959.
The Jarbidge Mountains, of which the mining district is a small part, separate two major physiographic provinces: the Snake River Plain to the north and the Great Basin to the south.
The district is underlain by Tertiary volcanic rocks that were extruded on an eroded surface of Paleozoic rocks that had been intruded by granitic stocks and dikes (Schrader, 1923, p. 12-35). The Paleozoic sedimentary rocks consist of quartzite, limestone, and shale and have been considerably folded. The intrusive rock is a gray coarsely crystalline hornblende-biotite granodiorite of probable Cretaceous age. The Tertiary volcanic rocks, mostly rhyolites, are divided into two series separated by an erosion surface.
The ore deposits are gold-bearing fissure veins in the older rhyolites. These veins range from 1 to 30 feet in width and from several hundred feet to several miles in length. They are grouped into a west and east system. In the west system the veins are the more valuable; they strike north-northwestward and dip steeply eastward. In the east system the veins are narrow but persistent; they strike northward and are exposed in rocks nearer the crest of the range.
The economic metals of the district are gold and silver, and they occur as native gold, electrum, argentite, cerargyrite, and naumannite (Schrader, 1923, p. 26). Pyrite is also present. The gangue consists chiefly of quartz and adularia. Other minerals present in minor amounts are apatite, barite, calcite, chalcedony, chlorite, epidote, fluorite, hematite, hyalite, kaolin, halloysite, leverrierite, limonite, psilomelane, pyrolusite, marcasite, opaline silica, sericite, and talc.
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