... shafts and by drilling. The ore deposits occur in the Galena dolomite and in the upper part of the Platteville limestone, both of Ordovician age. The ores are galena, smithsonite, and sphalerite, though the two latter are much less common now than... Congressional Serial Set - Página 5011911Vista completa - Acerca de este libro
| United States. Bureau of Mines - 1921 - 1278 páginas
...their "range." The ore bodies are sometimes continuous for long distances along these "ranges," which for that reason largely control the prospecting, both...limestone, both of Ordovician age. The ores are galena, smithsonite, and sphalerite, though the two latter are much less common now than formerly, when the... | |
| Illinois State Geological Survey - 1920 - 214 páginas
...mines of northern Illinois are all in Jo Daviess County, the extreme northwest county of the State. The ore deposits occur in the Galena dolomite and...the Platteville limestone, both of Ordovician age. They are galena, smithsonite, and sphalerite, though the two latter are much less common now than formerly,... | |
| United States. Bureau of Mines - 1916 - 1090 páginas
...long distances along these "ranges," which for that reason largely control the prospecting, both r>y shafts and by drilling. The ore deposits occur in the Galena dolomite and hi the upper part of the Platteville limestone, both of Ordovician age. The ores are galena, smithsonite,... | |
| United States. Bureau of Mines - 1911 - 632 páginas
...counties, and comprise the most important part of the ore deposits of the upper Mississippi Valley region. The ore deposits occur in the Galena dolomite and in the upper part of the Platteville 97M7°— MB 1909, PT 1 34 Ore. Metal content. District. Lead concentrates. Zinc concentrates. Lead.... | |
| 1912 - 1062 páginas
...counties and comprise the most important part of the ore deposits of the upper Mississippi Valley region. The ore deposits occur in the galena dolomite and...of Ordovician age. The ores are galena, sphalerite District. Lead concentrates. Ore. Zinc concentrates. Metal content. Cuba City-Elmo. Dodgevifle Hazel... | |
| United States. Bureau of Mines - 1916 - 1150 páginas
...long distances along these "ranges," which for that reason largely control the prospecting, both Ъу shafts and by drilling. The ore deposits occur in the Galena dolomite and in the upper part of the Plattevillo limestone, both of Ordovician age. The ores are galena, smithsonite, and sphalerite, though... | |
| United States. Bureau of Mines - 1917 - 1200 páginas
...long distances along these "ranges," which for that reason largely control the prospecting, bothby shafts and by drilling. The ore deposits occur in...Platteville limestone, both of Ordovician age. The ores aro galena, smithsonito, and sphalerite, though the two latter are much less common now than formerly,... | |
| United States. Bureau of Mines - 1919 - 970 páginas
...long distances along these "ranges," which for that reason largely control the prospecting, botnby shafts and by drilling. The ore deposits occur in...limestone, both of Ordovician age. The ores are galena, smithsonite, and sphalerite, though the two latter are much less common now than formerly, when the... | |
| United States. Bureau of Mines - 1919 - 972 páginas
...have been given in the reports in Mineral Resources of the United States for the years 1907 to 1915. The ore deposits occur in the Galena dolomite and in the upper part of the Plattcville limestone, both of Ordovician age. The ores are galena, sphalerite or zinc blende, with... | |
| Illinois State Geological Survey - 1920 - 216 páginas
...mines of northern Illinois are all in Jo Daviess County, the extreme northwest county of the State. The ore deposits occur in the Galena dolomite and...the Platteville limestone, both of Ordovician age. They are galena, smithsonite, and sphalerite, though the two latter are much less common now than formerly,... | |
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