Oro Plata Mine (Golconda Extension Mine), Todd's Basin, Cerbat, Cerbat Mining District, Wallapai Mining District, Cerbat Mountains, Mohave County, Arizona, USAi

Regional Level Types
Oro Plata Mine (Golconda Extension Mine)	Mine
Todd's Basin	Basin
Cerbat	Town (Former)
Cerbat Mining District	Mining District
Wallapai Mining District	Mining District
Cerbat Mountains	Mountain Range
Mohave County	County
Arizona	State
USA	Country

ORO PLATA MINE.

The Oro Plata mine, one of the heaviest and most continuous producers, is located in the eastern part of the district near the axis of the range and the head of the main gulch, at an elevation of about 4,300 feet. It is reached by wagon road. The mine was first located and owned by Mexicans, under whom it began to be worked early in the seventies. It was next owned by J. P. Lane, whom the tailings are said to have netted $70,000, but who, in 1882, sold it to a party of ranchers under the lead of H. Wilson. These men worked it and shipped ore to the smelters in Colorado, and finally sold the mine to J. W. Garret in 1895. In 1897 and 1898 the mine produced $150,000. Recently it has been purchased by the Oro Plata Mining Company, of St. Louis.

The mine is developed to a depth of 280 feet, principally by shafts, drifts, adit drifts, tunnels, and stopes, aggregating, it is said, about 7,000 feet of underground work distributed on three levels. The mine produces considerable water, ample for all milling purposes. The principal surface equipments are a 20-horsepower steam hoist and an air compressor. At the time of visit ground was being broken for a new mill.

The country rock is the pre-Cambrian gneiss, extensively intruded by coarse granite porphyry, a large dike of which crosses the gulch just below the mine. In the mine the granite porphyry seems to be associated with the vein, as does also a large 40-foot dike of finer grained granite porphyry.

The vein, about 4 feet in width, normally dips about 80° NE. It is locally enriched by intersection with another vein.

The ore, which occurs chiefly in a banded quartz gangue, contains principally gold and silver. There are small amounts of chalcopyrite, zinc blende, pyrite, and galena. The ore shoots are said to be richer and more regular in the deeper part of the mine than near the surface. The ore averages in gold 3 ounces and in silver 25 ounces to the ton, and in lead about 6 per cent. There is said to be good ore in the bottom of the mine, which carries about 7 per cent of lead. The value of the output of the mine from July 14, 1896, to February 18, 1901, as shown by the sheets of the Arizona Sampler Company, which bought the ore at Kingman, was approximately $206,000 (2,527 tons of ore, averaging $80 to the ton), of which about 75 per cent was in gold and the balance in silver and lead. The price paid in the recent purchase of the mine was based on the assumption that the ore on the whole averages $37 to the ton, including the large bodies of moderate-grade ore left in the mine above the 280-foot level during earlier work.

The total production is reported to be about $500,000, and about 5,000 tons of second-class ore, said to average about $20 a ton, lie on the dump.