Mineral Resources of the United States, Del 1

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U.S. Government Printing Office, 1922

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Side 452 - No. 185, which may be obtained on application to the Director of the United States Geological Survey, Washington, DC...
Side 365 - From such figures as are available, showing the relation between crude ore treated and beneficiated ore recovered, it is apparent that in washing brown ore the ratios, by weight, of crude ore washed to resultant concentrates range from...
Side 95 - The operators in Michigan report the quantity of concentrates produced and the actual recovery of copper from concentrates smelted. In any year the mines may produce more or less concentrates than are smelted during the same period. The copper content of concentrates produced...
Side 103 - The lead and zinc deposits of Illinois fall into two distinct regions marked by different mineral association and structural environment. Those of southern Illinois belong to the Kentucky-Illinois fluorspar district; those of northern Illinois belong to the upper Mississippi Valley region. NORTHERN ILLINOIS.
Side 104 - Illinois, 1906 to 1918, inclusive, has been 7,743 tons, most of which has been shipped from the Fairview and Rosiclare mines. The shipments of zinc ores from the district have been comparatively small and scattered. The only recorded shipments of zinc carbonate were made from the Empire mine in 1903 or 1904, and in 1906 four companies made shipments aggregating 103 tons.
Side 104 - Southern Illinois. — The lead and zinc deposits of southern Illinois are found in Pope and Hardin counties in rocks of Mississippian age in the northern extension of the Kentucky-Illinois fluorspar district. The principal product of the mines in recent years has been fluorspar, and the yield of galena is small compared with the output from other districts in the Central States. The total production of galena concentrates TARLE 29. — Production and value of lead, zinc, and silver in Illinois,...
Side 508 - Sacramento obtained most of their gold by dredging; Amador and Calaveras are on the Mother Lode; and Nevada County produced mainly from siliceous ores of the Grass Valley district. The five Mother Lode counties — Amador, Calaveras, Eldorado, Mariposa, and Tuolumne — whose output is mainly gold milling ores, produced...
Side 371 - Jan. Feb. Mar. Apr. May June July AUK. Sept. Oct.
Side 111 - amygdaloid. A large percentage of the production in the past has come from the conglomerate lode, but with the decrease in copper content of this lode and its approaching exhaustion the mining from the amygdaloid lodes has increased. The company's annual report showing the details of operation for 1911 is not yet available.
Side 124 - The following table gives the output of< crude lead and zinc ore for the whole State of Oklahoma, but it was thought advisable to calculate the tenor of crude ore and concentrates as well as assay content and value of concentrates separately for the Miami and Quapaw districts, inasmuch as the character of the ground operated in these districts...

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