The Tuscarora district is 45 miles northwest of Elko, near the headwaters of the South Fork of the Owyhee River.
Gold was discovered in the area in 1867 in stream gravels (Browne, 1868, p. 429-430), and outcrops of auriferous vein material were found soon afterward. During the following 9 years placers were mined, but there was no intense activity until 1876 when high-grade ore was found in the Grand Prize mine (Nolan, 1936a, p. 7-9). The usual boom period followed, accompanied by mismanagement, waste, litigations, and profiteering, so typical of the histories of mining camps throughout the West. By 1886 the bonanza ores were exhausted, but new discoveries to the north and west created another boom, though of lesser proportions. A third revival was created by the mining of low-grade gold ores from the Dexter mine (Nolan, 1936a, p. 9), and most of the production of the district from 1895 to 1912 was from this mine. In recent years the district declined steadily with no production reported from 1955 through 1959.
Nolan (1936a, p. 10-14) in reviewing the production history of the district noted that estimates of production before 1902 varied widely, but that a reasonable compromise would be about $10 million in gold and silver. From 1902 through 1959, a total of 15,662 ounces of gold was mined, most of it from lodes. The placer gold production of the district, most of it mined in the early days, amounted to about $700,000 (Nolan, 1936a, p. 14). Total gold production of the district through 1959 probably was at least 100,000 ounces.
The bedrock of the area consists of bedded volcanic breccias and tuffs about 5,000 feet thick and dark-green andesite porphyry that is intrusive into the pyroclastics (Nolan, 1936a, p. 14-35). The bedded rocks have been tilted to the east and southeast. The rocks are also faulted, but the nature and extent of faulting are not clear.
There are three types of deposits: (1) silver lodes rich in native silver and silver halides, argentite, stephanite, proustite, pyrargyrite, pyrite, enargite, arsenopyrite, bornite, chalcopyrite, sphalerite, and galena with quartz and calcite gangue, in the andesite masses; (2) gold deposits consisting of quartz and adularia fissure fillings and zones of quartz stringers in the bedded pyroclastics; and (3) gold placers.
Page 3 of 3