Wonder Mine, Ophir Mountain, Darwin Mining District, Darwin Hills, Inyo County, California, USAi

Regional Level Types
Wonder Mine	Mine
Ophir Mountain	Mountain
Darwin Mining District	Mining District
Darwin Hills	Group of Hills
Inyo County	County
California	State
USA	Country

A former small Pb-Ag-Cu-Au mine located in the NW¼ sec. 18, T19S, R41E, MDM, 2.2 km (1.37 mi) ESE of Ophir Mountain (coordinates of record) and 7,290 feet (ca. 2,222 m) N38E from Darwin, at an elevation of 4540 feet (ca. 1,384 m) (N and S of the Lane Canyon Road (now N. Main Street)). The property consisted of 4 claims. Originally owned by Richard Wallace, later the Anaconda Co. owned the mine. Operated in 1947. MRDS database stated accuracy for this location is 100 meters. Updated description and position of the mine N36.28397 W117.57632 and N36.28501 W117.57648 by Richard Muster, based on observations in 2007. The older parts of the workings are at N36.28020, W117.58036; N36.27976, W117.57995; N36.28003, W117.57941 and N36.28054, W117.57949.

It is argued by some that the Wonder Mine and the Bruce Mine are one entity, but Hall, Wayne Everett & E.M. Mackevett list them as separate mines; furthermore, the Wonder Mine is a Ag-Pb mine, whereas the Bruce Mine is a W mine.

Mineralization is hosted in hornfels. The orebody is lenticular, strikes N27W and dips 55SW, at a thickness of 1.83 meters. The ore occurs as irregular lenses of galena and lead-carbonate along a fissure in the limestone that strikes northwest and dips 45° W. The vein-filling is a coarse calcite with some crystalline fluorite. Local structures include a fault and fold. Local rocks include Carboniferous marine rocks, unit 2 (SE California Carbonate Assemblage).

Ore occurs along the vein. A steep N70E trending fault cuts the vein in the adit 60 feet (ca. 18 m) from the portal and off-sets the southern segment approximately 8 feet (2.44 m) to the W. Similar ore is exposed on the crest of an anticlinal fold at the collar of the inclined shaft or Wonder No. 1 claim. Ore extends down the west limb as a bedding plane vein 4 to 6 feet (1.83 m) thick, strikes N10W and dips 55SW.

Rocks in the area are calc-hornfels and locally tactite at the top of the lower member of the Keeler Canyon Formation. Rocks are intersected by a number of N70E fractures that are part of the Lane Fault, between the Wonder and Wonder No. 1 claims. North of the fault, the workings are along the crest of an open anticlinal-shaped fold.

Workings include surface and underground openings. The older workings consisted of an adit S of the Canyon Road. The newer workings, N of the Canyon Road, consisted of 2 inclined shafts, an adit and several surface pits. Little is known of the older parts. The mine N of the Canyon Road was mainly worked in 1947.

Production data are found in: Goodwin, J.G. (1957): 523.

Considerable ore was shipped in 1947. Smelter recovery was 2.45% Pb, 3.84 ounces (ca. 145 g) Ag/ton plus recoverable Cu.

Other Databases

Link to USGS MRDS:	10261093

Other Regions, Features and Areas containing this locality

References