Silver and Gold: an Account of the Mining and Metallurgical Industry of the United States: With Reference Chiefly to the Precious MetalsJ.B. Ford, 1873 - 566 من الصفحات |
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الصفحة 18
... thick . Lay it out in 12 - inch squares , take a smaller quantity from each square , take samples thus obtained , and again mix them . Again spread out , say , one inch thick , laid out into 4 - inch squares , taking a smaller portion ...
... thick . Lay it out in 12 - inch squares , take a smaller quantity from each square , take samples thus obtained , and again mix them . Again spread out , say , one inch thick , laid out into 4 - inch squares , taking a smaller portion ...
الصفحة 52
... thickness of about 150 feet ; its elevation at Jamestown is about 500 feet above the surround- ing country . Beneath this capping of lava is a stratification of sand- stone sixty to one hundred feet in thickness ; and underneath this ...
... thickness of about 150 feet ; its elevation at Jamestown is about 500 feet above the surround- ing country . Beneath this capping of lava is a stratification of sand- stone sixty to one hundred feet in thickness ; and underneath this ...
الصفحة 53
... thickness and prospects largely from top to bottom , several pan tests having shown the extraordinary average of three to five cents to the pan . The company are now build- ing a ditch , taking the water out of the Tuolumne River , at a ...
... thickness and prospects largely from top to bottom , several pan tests having shown the extraordinary average of three to five cents to the pan . The company are now build- ing a ditch , taking the water out of the Tuolumne River , at a ...
الصفحة 55
... thickness . The figures on the left - hand side represent feet , and show the thickness of the different 153 Slate . strata . The skull was found in the five - foot gravel - bed above the " red lava . " When the State geologist shall ...
... thickness . The figures on the left - hand side represent feet , and show the thickness of the different 153 Slate . strata . The skull was found in the five - foot gravel - bed above the " red lava . " When the State geologist shall ...
الصفحة 58
... thick , averaging 24 feet . The average pay of the rock is now about $ 44 per ton . Their tunnel is in 1,100 feet , on a level with the mill , to which the rock is easily taken by car . At the back of the tunnel they have sunk a shaft ...
... thick , averaging 24 feet . The average pay of the rock is now about $ 44 per ton . Their tunnel is in 1,100 feet , on a level with the mill , to which the rock is easily taken by car . At the back of the tunnel they have sunk a shaft ...
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50 feet amalgam amount antimony arrastra assay average Bannack base bullion bed-rock bullion Calaveras County California Cañon carbonate cent chemical claim coal commenced company's contains copper cost County course Creek Cupellation December deposits depth developed district ditch drift drill east El Dorado County engine erected Eureka expense extracted feet deep feet in length feet long feet wide furnace galena gangue gold Gold Hill gravel ground Gulch Hill hundred hydraulic inches incline iron labor lead ledge limestone located lode metallurgy metals miles mill miners Mining Company months nearly Nevada opened operations ounces owners placer mines pounds present Professor prospecting quantity quartz quartzite rich River rock San Francisco silver slag slate smelting smelting-works stamps stopes sulphurets sunk supply surface Table Mountain tailings thick tion tons Total tunnel Tuolumne County tuyeres Valley vein width yield