Location
On the east flank of the While Hills and on the east and west flanks of the Lost Basin Range, south of Lake Mead, Tps. 29 and 30 N., Rs. 17 and 18 W.
Topographic Map
Garnet Mountain 15-minute quadrangle.
Geologic Map
Wilson and Moore, 1959a. Geologic map of Mohave County, Arizona, scale 1:375,000.
Access
From Kingman, 29 miles north on U.S. Highway 93 to Pierce Ferry Road; this road leads northeast about 22 miles to the Gold Basin area and 30 miles to the Lost Basin area.
Extent
The placers in the Gold Basin and Lost Basin districts are found in three major areas: the east and west flanks of the Lost Basin Range and the detrital fan in Gold Basin on the east flank of the White Hills. The placers on the east flank of the Lost Basin Range are found in arroyos incised in bajada gravels of late Miocene and early Pliocene age which cover an area of 8-10 square miles.
Many individuals have drywashed the placers at various localities. Five major placer claims are located along this flank of the range. These are the Robeson and Joy lease (sec. 14, T. 30 N., R. 17 W.), the Queen Tut placer (sees. 27 and 34, T. 30 N., R. 17 W.), the Golden Nugget placer (near the intersection of sees. 33 and 34, T. 30 N., R. 17 W.; sees. 3 and 4, T. 29 N., R. 17 W.), the King Tut placer (sec. 9, T. 29 N., R. 17 W.), and the Lone Jack placer (sec. 16, T. 29 N., R. 17 W.).
The King Tut placer was the most actively mined placer in the area, and the east flank of the Lost Basin Range is frequently called the King Tut placer area.
On the west flank of the Lost Basin Range, small-scale mining of placers found in Quaternary alluvial fans is still active. These placers occupy an area comparable in size to the placer ground on the east side of the range and are located in the eastern rows of T. 29 and 30 N., R. 17 W.
The gold-bearing gravels of the Gold Basin district are found in arroyos and gulches on the large detrital fan that slopes eastward from the White Hills to Hualapai Wash and is traversed by White Elephant Wash and its tributaries. The Searles placer mine is in sec. 29, T. 29 N., R. 18 W.
Production History
The placers in the Gold Basin and Lost Basin districts were first actively mined in 1931, about 60 years after the discovery of lode gold. Placer gold was recovered from the Gold Basin district in 1909, but, probably because of the isolation of the district, apparently no further placer mining was done until 1931.
Placer-mining activity since the early 1930's has been almost continuous but on a small scale. A few mining operations have used power shovels and small dry-concentrating plants to mine the gravels, but most activity was with the small portable drywasher so prevalent in the Southwest.
Owing to the relatively late development of the placers, early miners were able to sample virtually untouched placer ground in this area. On the east flank of the Lost Basin Range, the richer gold-bearing gravels are generally less than 2 feet thick and rest on caliche-cemented gravels.
The gold contained in these surface gravels ranges in size from fine dust to nuggets as much as three-quarters of an ounce; in 1941, a nugget valued at $140 (4 oz) was recovered from a placer near the King Tut. Extensive sampling of one section at the King Tut placers in 1933 indicated that the average value of the placers was $1.17 per cubic yard.
The gold-bearing gravels of the Gold Basin area are 1-3 feet thick and rest on cemented gravels. The gold ranges in size from fine to coarse; fragments found range in value from 5 cents to $3.50. The gold is reported to be erratically distributed; thin streaks that yield more than $1.00 per cubic yard are found, but most arroyo gravels contain less than $1.00 per cubic yard.
Source
Recent work by the U.S. Geological Survey indicates that there are many small gold-quartz-carbonate-sulfide veins in the Precambrian rocks. Gold derived from some of these veins is the probable source of the placers.
Literature
Blacet, 1969: Brief summary of type of lode deposits; notes presence of scheelite in the placers.
Engineering and Mining Journal, 1933b: Placer-mining activity in 1933; location of placer area sampled.
1941: Size of nuggets.
Mining Journal, 1933: Placer-mining operations; average value of placer gravels at King Tut placer.
U.S. Geological Survey, 1968: Extent and age of placers; average value of placers; source of gold.
Wilson, 1961: Location; placer-mining operation during the period 1932-33; extent and thickness of gravels, accessory minerals; average value of gravels; size of gold particles; source.
