Other Names: Mason, Mason Pass, Mason Valley, Ludwig, Indian Spring, Indian Springs
Commodities: copper, gold, turquoise, iron, nickel
The Yerington district includes all of the Singatse Range, including the towns and camps of Yerington, Mason, and Ludwig; Mason Valley; and a small part of the Wassuk Range east of Mason Valley. Perry’s map (1865) shows the historic Indian Spring[s] district to include what is now the Yerington district.
Perry, 1865; Angel, 1881, p. 498; Stuart, 1909, p. 140; Hill, 1912, p. 219; U.S. Geological Survey, 1922, p. 328; Lincoln, 1923, p. 133; Stoddard, 1932, p. 57; Stoddard and Carpenter, 1950, p. 83; Reeves and others, 1958, p. 68; Moore, 1969, p. 26; Papke, 1975, p. 59
Yerington Placer District Description
In the Singatse Range between Gallagher and Mason passes at the north end of Smith Valley, T. 14 N., R. 24 E.
Como and Wabuska 15-minute quadrangles.
Moore, 1969, Geologic map of Lyon, Douglas, and Ormsby Counties, Nevada (pi. 1), scale 1:250,000. Knopf, 1918, Geologic map of the Yerington district, Nevada, (pi. 1), scale 1:24,000.
From Reno, 35 miles east on U.S. Highway 40 to Fernley and junction with U.S. Highway 95A; from there, it is 34 miles south to Wabuska. About 5 miles south of Wabuska, dirt roads lead west to the Singatse Range. The dirt road 2 miles south of the Gallagher Pass road leads directly to placer area.
The placers in the Yerington district are in a stream channel that traverses the Singatse Range on the west side of Carson Hill (sees. 23 and 24, T. 14 N., R. 24 E., unsurveyed) 6 miles north of the Anaconda Co. copper mine at Weeds Heights. The stream channel is about 2 miles long and 300-600 feet wide; the gravels, which average 20 feet thick, were mined for a distance of about 0.9 mile along the channel between two parallel dirt roads that branch and rejoin at the margins of the placer area. This deposit is known as the Adams-Rice (or Guild) placer.
The upper parts of the channel gravels consist of small sub- angular cobbles, pebbles, and sand, crudely or poorly stratified. In places, the lower parts of the channel consist of cemented gravels containing well-rounded boulders interpreted by some geologists as a part of a Tertiary river system. Most of the gold was apparently found in the recent gravels and was observed to have two shapes, angular and water- worn, indicating that some of the gold was reconcentrated from the older gravels.
Small amounts of placer gold were found in the alluvial fan at the mouth of the canyon (sec. 18, T. 14 N., R. 25 E., Wabuska quadrangle), but little work has been done in this area.
The Penrose placer is about 2 miles southwest of the Adams-Rice (or Guild) placer in Lincoln Flat. The exact location is uncertain but is probably in the low hills on the west side of the range and about 3 miles north of Wishart Hill at the north end of Smith Valley (approximately sec. 22, T. 14 N., R. 24 E., unsurveyed, Como quadrangle). The Penrose placer is in gravels of the Tertiary river channel, which are as much as 120 feet thick; the average value of the gravels is 20 cents per cubic yard.
Penrose (1937, p. 4) states that 90 percent of the material in the 120-foot-deep shaft and drifts from the shaft was foreign to the area; he found well-rounded fragments of serpentine and pieces of steatite.
The placer production from the Yerington placers has been small, despite the active development of the placers during the 1930's. Some placer gold was reported from the district in 1917, but the Adams-Rice and Penrose placers were discovered in 1931 (1929-30 according to Penrose). The Adams-Rice placer was worked by a cater- pillar-mounted dryland dredge, which reportedly recovered an average of 60 cents per cubic yard. The Penrose placer was worked by a dry-concentrating table.
The ancient river channel that underlies the placer gravels in the Yerington district is thought to be a continuation of the Tertiary (early Miocene) fluvial conglomerate that occurs at the base of the Hartford Hill Rhyolite Tuff and overlies Cretaceous granodiorite, mapped by Knopf (1918) just south of the placer area. The conglomerate trends northeast from the north end of Wishart Hill. The conglomerate contains well-rounded, but unsorted and unstratified, cobbles and boulders; the cobbles are mainly andesite, and the boulders are granitic siliceous sediments.
If some of the gold in the placers was derived by reworking this fluvial conglomerate, that gold was derived from a source exposed in the early Tertiary. The ultimate source of this gold is unknown.
The angular fragments of gold found in the recent gravels at the Adams-Rice (or Guild) placer are thought to be derived from quartz veins at the head of the canyon.
Huttl, 1934: Describes dryland dredge used by Apex Mining Co.; de- tails of gold-recovery techniques; average value of gravel mined.
Mining Journal, 1945: Reports development plans by Singatse syndicate to mine lava-capped placers.
Moore, 1969: Locates Guild placer mines.
Penrose, 1937: Describes Tertiary river channel; locates channel and traces extent for 6 miles; character of gold in channel; depth of shaft at Penrose placer; type of rocks found in shaft; difficulties in mining gravels.
Stoddard and Carpenter, 1950: Location of placer claims; placer-mining operations; production from these operations; depth of gravel; reported average value per cubic yard; size of gold recovered; source.
Vanderburg, 1936a: Describes Adams-Rice placer—location; average depth to bedrock; different types of gravel; lithology of ancient river channel gravel; size and shape of gold in gravels; size of largest nugget found; placer-mining operations. Describes Penrose placer—location; age of gravel channel; lithology of gravels; average value of gravels; size of gold.