Gold and Silver: Comprising an Economic History of Mining in the United States, the Geographical and Geological Occurrence of the Precious Metals, with Their Mineralogical Associations, History and Description of Methods of Mining and Extraction of Values, and a Detailed Discussion of the Production of Gold and Silver in the World and the United StatesJ. Wiley & Sons, 1908 - 727 strani |
Iz vsebine knjige
Zadetki 1–5 od 36
Stran ix
... Sluices in Hydraulic Mining facing 370 A Yuba River Dam and Flume , Grass Valley , California 383 Arrangement of Sluices on a Gold Dredger facing 400 Stope in Silver Wave Mining District , Colorado facing 430 Method of Overhand Stoping ...
... Sluices in Hydraulic Mining facing 370 A Yuba River Dam and Flume , Grass Valley , California 383 Arrangement of Sluices on a Gold Dredger facing 400 Stope in Silver Wave Mining District , Colorado facing 430 Method of Overhand Stoping ...
Stran 316
... sluices . The source of the gold is numerous small quartz - veins . An ample water supply together with the absence of clay and large boulders and a soft and easily cleaned bed - rock render the district especially adapted to dredging.3 ...
... sluices . The source of the gold is numerous small quartz - veins . An ample water supply together with the absence of clay and large boulders and a soft and easily cleaned bed - rock render the district especially adapted to dredging.3 ...
Stran 323
... sluices . The gravel carries from 6 to 8 cents per cubic yard in gold . ' The beach mines of the state , especially at the mouth of the Rogue River , were at one time among the richest of all the placers . The mouth of the Coquille ...
... sluices . The gravel carries from 6 to 8 cents per cubic yard in gold . ' The beach mines of the state , especially at the mouth of the Rogue River , were at one time among the richest of all the placers . The mouth of the Coquille ...
Stran 343
... sluice - box and long- tom are used , as they handle larger quantities with less labor . The sluice - box , generally 8 to ... sluices after it had been broken down from the bank . ( Natural His- tory , Bohn's Edition , Vol . vi , p . 99 ) ...
... sluice - box and long- tom are used , as they handle larger quantities with less labor . The sluice - box , generally 8 to ... sluices after it had been broken down from the bank . ( Natural His- tory , Bohn's Edition , Vol . vi , p . 99 ) ...
Stran 344
... sluicing . Large areas of ground could be rapidly worked over when the lay of the ground provided sufficient grade and when considerable water was available . The sluices consisted of trenches cut in the ground and lined with rock walls ...
... sluicing . Large areas of ground could be rapidly worked over when the lay of the ground provided sufficient grade and when considerable water was available . The sluices consisted of trenches cut in the ground and lined with rock walls ...
Druge izdaje - Prikaži vse
Pogosti izrazi in povedi
Alaska amalgamation andesite argentiferous assay auriferous average bed-rock blende bornite calcite California Carolina cent chalcopyrite chloride chlorination Colorado Comstock lode concentration considerable copper country-rock County Cripple Creek cyanide cyanide process Deep Mines deposits depth diorite discovered discovery district dollars drift employed extraction feet free-gold furnace galena gangue gneiss gold and silver gold production Gold-bearing granite gravel gray copper Gulch Hill hydraulic Ibid Idaho inches iron Jour lead limestone located mercury method Mexico mill Mineral Industry Mineral Resources Mines and Minerals Montana Mountain Nevada North occur operations ore-bodies ounces output oxide placer mines placers porphyry precious metals Press probably production of gold pyrite pyrrhotite quantities quartz quartz-veins quartzites Rept rhyolite River rocks schists shaft siliceous silver production Silver-bearing slate sluices smelting solution South stamps stope sulphides sulphurets surface TABLE tellurides tellurium tetrahedrite timber tion tons Total tunnel Utah yield zinc