AMERICAN MINING STATISTICS.

Thames Star, Volume VII, Issue 2104, 1 October 1875, Page 4

AMERICAN MINING STATISTICS.

The gold yield of California in 1853 exceeded eleven millions sterling. The gross yield from quartz mines is increasing slowly. The capital invested in mines and mining is returning about 20 per cent. The average earnings per miner is at least 12s per day on tliose mines which are opened. In some of the well-known mines the yield averagesfSll the year round £4 per day for every hand employed.

In the mills of the Virginia City alone, they use no less than 923 pans of various , makes, including the Knox, Wheeler, Hepburn, Varney, Whakelle, and Plain ; and 400 settler*, agitators, grinders, barrels, tubs, and concentrators.

Fine Gold : In the year 1860 the yield of gold was found to be in the Pine Tree district, only 40 per cent, of the actual contents, owing to its being so fine as to be invisible to the naked eye. In the Mariposa district, for the same reason the gold quartz which now yields £10 to £12 per ton used only to give £2 to £3. In the Pine Tree the whole cost of treatment only averages 24s per ton. Seduction Works: In the state of Nevada there are no less than 170, and their cost is put down at two millions •terling.

Aqueducts: One is now being constructed to convey the west branch of the Carson River thirty miles to the Empire City. Another, known as the Humboldt Ditch, will be no less than sixty miles in length. Both of these were built for conveying water to the mines. Run of Gold in Quartz Reefs : Careful and systematic observation has demonstrated that they are rarely worked to a profit for more than two consecutive miles ; and the pay rock rarely extends for more than l-,000 feet along a vein. A large mineral vein, however, is often traceable for thirty or forty miles in a straight line, the rich portions being often far apart, and the intervals barren; The observation is the result of a very large experience, and no doubt applies to this as well as to other.countries. r

The Comstock lode, believed to be the richest in the world, embraces an area of three mijes in length, and a third of a mile in width —equal to an'area of a square mile. It produces, annually two and a half millions sterling, while the loss on the ores represents not less than a third of the entire value—so that something like three-quarters of a million is allowed to go to waste every year. About 5,000 men are employed, and their average earning is""equal to £500 per man, per finnum;' The excavations in tunnels, shafts, &c, aggregate 17^- miles. The timber for mine use, and firewood, costs annually £200,000. Taxes on mining industry are very equitable in their character :•—• half per cent, is paid on bullion; every miner earning over £200 a year, pays £2 to the revenue.