Sidewinder Mine, Sidewinder Mountain, Rodman Mountains, Belleville Mining District, San Bernardino County, California, USAi

Regional Level Types
Sidewinder Mine	Mine
Sidewinder Mountain	Mountain
Rodman Mountains	Mountain Range
Belleville Mining District	Mining District
San Bernardino County	County
California	State
USA	Country

A former Au-Ag-Cu-Mn occurrence/mine located in the SW¼ sec. 4, and the SE¼ sec. 5, T6N, R2W, SBM, 6.2 km (3.8 miles) WNW of Sidewinder Mountain summit (coordinates of record) (0.7 mile E of Black Mountain summit), on private land. The property is comprised of 3 patented claims. MRDS database stated accuracy for this location is 10 meters. Opened in the 1880's and worked intermittently until 1942. This was the largest gold operation in the Barstow-Victorville area.

Mineralization is a vein deposit hosted in rocks of the Galice Formation (rhyolite of the Sidewinder volcanic series, dacite and Late Jurassic quartz monzonite). The ore body is irregular in form, strikes NW and dips 35 to 45. A fault separates rhyolite and dacite on the SW from quartz monzonite porphyry on the NE. The former are part of the Sidewinder volcanic series of probable Jurassic or Triassic age. The quartz monzonite is believed to be of Late Jurassic age. A siliceous vein lies in the fault and is exposed laterally for 3,000 feet. The strike of the veins are variable according to Bowen, from N80E at surface to N80W. The veins appear to be discontinuous. In the vicinity of the Doherty shaft, the hanging wall rocks are meta-dacites and meta-felsites of the Sidewinder volcanic series, and the footwall is quartz monzonite. Both walls in the most eastern workings are hydrothermally altered felsite. Both walls are quartz monzonite in the most easterly of 3 west shafts. Local rocks include Mesozoic volcanic rocks, unit 3 (Mojave Desert, Death Valley area, and Eastern Sierra Nevada).

Local structures include a shear zone striking N80E, and dipping 64-80S, 200 feet SE of the main adit vein in quartz monzonite. It is paralleled by a normal fault which crosses the open cut N of the main adit portal.

Workings include underground openings with a length of 914.4 meters and an overall depth of 243.84 meters and comprised of 2 inclines, the Doherty and Armstrong shafts. The Doherty is 600 feet deep with 4 levels spaced at 100 foot intervals and with drifts totaling 1,000 feet, 1,300 feet, 400 feet and 300 feet, respectively. There is a SW-trending adit on the 200 foot level. The Armstrong shaft is about 800 feet deep. There are also several shallower shafts on the property. The combined length of workings totals approximately 3,000 feet. Detailed descriptions of workings can be found in Bowen (1954).

Production data are found in: Bowen (1954), and Tucker & Sampson (1931).

The ore produced in 1887 had an estimated yield of $30 (period values) Au/ton (free-milling). Cumulative production from estimates by the U.S. Bureau of Mines.

Other Databases

Link to USGS MRDS:	10086498

Other Regions, Features and Areas containing this locality

References