 Of these openings there are five or six, the "top," "middle," and "third" being the most prolific of ore. The "flats" and "pitches" common in the Wisconsin mines have been found in only one or two instances in Iowa. The crevices have an east-west trend...  Mineral Resources of the United States - Page 80by United States. Bureau of Mines - 1914Full view - About this book
 | United States - 1911 - 632 pages
...the most prolific of ore. The "flats" and "pitches" common in the Wisconsin mines have been found in only one or two instances in Iowa. The crevices have...deeper levels in these old ranges which are known to nave yielded ore in former days in the upper openings. There are but two lead and zinc concentrating... | |
 | Digital images - 1912 - 1062 pages
...most prolific of ore. The " flats " and " pitches " common in the Wisconsin mines have been found in only one or two instances in Iowa. The crevices have...mined at different places, in which case they are District. Lead concentrates. Ore. Zinc concentrates. Metal content. Dubunue: 1911 1910 1909 1908 Galena.... | |
 | United States. Bureau of Mines - Digital images - 1916 - 1150 pages
...the most prolific of ore. The "flats" and "pitches" common in the Wisconsin mines have been found in only one or two instances in Iowa. The crevices have...confined to attempts to find paying ore at deeper levels m these old ranges, which are known to have yielded ore in former days in the upper openings. There... | |
 | United States. Bureau of Mines - Digital images - 1917 - 1200 pages
...ore. The "flats" and "pitches" common in the Wisconsin mines have been found in only one or two places in Iowa. The crevices have an east-west trend and...to attempts to find paying ore at deeper levels in tfrese old ranges, which are known to iiave yielded ore in former days in the upper openings. There... | |
 | United States. Bureau of Mines - Digital images - 1918 - 1100 pages
...3,096 4,284 96 35 395 $10,368 3,780 37, 130 MINERAL RESOURCES, 1912. known as "ranges." The raining operations of recent years have generally been confined...in the upper openings. The only production of lead in the Duhuque district in 1912 was 78 short tons of lead concentrates, sold in small lots. No sales... | |
 | United States. Bureau of Mines - Digital images - 1919 - 972 pages
...The"flats" and "pitches," common in the Wisconsin mines, have been found in only one or two places in Iowa. The crevices have an east-west trend and...ranges, which are known 'to have yielded ore in former davs in the upper openings. There was no production of either lead or zinc reported by Iowa mines in... | |
 | United States. Bureau of Mines - Digital images - 1921 - 1102 pages
...The "flats" and " pitches," common in the Wisconsin mines, have been found in only one or two places in Iowa. The crevices have an east-west trend and...places, in which case they are known as "ranges." The estimated output of 60 tons of zinc carbonate and 43 tons of galena concentrates in 1917 was derived... | |
 | United States. Bureau of Mines - Digital images - 1921 - 1282 pages
..." flats '' and " pitches," common in the Wisconsin mines, have been found in only one or two places in Iowa. The crevices have an east-west trend and...places, in which case they are known as " ranges." Xo shipments of lead or zinc concentrates from mines in Iowa were reported in 1918. MINERAL EESOURCES,... | |
 | United States - 1912 - 1046 pages
...most prolific of ore. The " flats " and " pitches " common in the Wisconsin mines have been found in only one or two instances in Iowa. The crevices have...mined at different places, in which case they are Ore. Metal content. Lead concentrates. Zinc concentrates. District. Lead. Zinc. Galena. Sphalerite.... | |
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