| United States. Department of the Treasury, John Ross Browne - Mines and mineral resources - 1867 - 326 pages
...mentioned the fact that the ores through all the levels explored retain their character of true silver ores which they had near the surface. The amount of lead,...ores, and these metals preserve now, at the lowest level, nearly the same relative proportion as formerly. Their increase, especially of lead, would be... | |
| United States. Congress. House - United States - 1867 - 780 pages
...Cumstock ores, and those metuls preserve now, at the lowest level, nearly the same relative proportion us formerly. Their increase, especially of lead, would...the most unfavorable indication for the future of tin1 Comstoek lode, as, besides the growing difficulty of metallurgical treatment, the conclusion would... | |
| John Ross Browne, James Wickes Taylor - Gold mines and mining - 1867 - 374 pages
...explored retain their character of true silver ores which they had near the surface. The amount of 1ead, copper, iron, and zinc has never been large in the Comstock ores, and these metalĀ« preserve now, at the lowest level, nearly the same relative proportion as formerly. Their increase,... | |
| Nevada. Legislature - 1875 - 870 pages
...that the ores, through all the levels explored, retain the character of true silver ores which the}' had near the surface. The amount of lead, copper,...of lead, would be the most unfavorable indication lor tlie future of the Comstock lode, as, besides the growing difficulty of metallurgical treatment,... | |
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