Bulletin - United States Geological Survey, Ausgabe 427

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Seite 161 - The country rock is jasper, thin layered and separated by seams of shale. The jasper layers differ in thickness from a fraction of an inch to several feet. The same layer varies in thickness, pinching out locally In many places. Most of the shale seams are thin. Both shale and jasper are greenish gray except where stained red or black by iron or manganese. The dip of the layers is about 35° W., the strike being a little east of north.
Seite 280 - Prices are based on ores containing not more than 8 per cent silica or 0.20 per cent phosphorus, and are subject to deductions as follows: For each 1 per cent in excess of 8 per cent silica there shall be deduction of 15 cents per ton; fractions in proportion.
Seite 70 - HAYES, CW, and ECKEL, EC Iron ores of the Cartersville district, Georgia. In Bulletin No. 213, pp. 233-242. 1903.
Seite 281 - The following table shows the total quantity of manganese ore imported into the United States as far as has been recorded. The figures from 1868 to 1888 represent imports from Canada only. Those from 1889 to the present time represent total imports. Imports of manganese ore into the United States, 1868-1908, in long tons.
Seite 284 - PRICES. The prices of iron-manganese alloys vary with the content of these metals. However, as the alloys are generally made with a fairly definite composition, the prices vary only within small limits. The following table shows the average range of prices for various iron-manganese alloys during 1908. Prices per long ton of iron-manganese during 1908. Ferromanganese" $44-$48 Spiegeleisen " 30-34 Silicomanganese 90-125 Silicospiegel
Seite 210 - Tchiatouri manganese ore are unfavorable in that the proportion of large pieces obtained is small, and much of the ore is quite soft, and grinds to a fine powder during the handling incidental to mining, cleaning and transportation. The loss of ore during concentration and transport is therefore considerable; and much of the fine ore shipped is considered objectionable by consumers.
Seite 25 - ... (3) Ores that are too low in silver and lead to be used directly as a source of these metals and too low in iron and manganese to be used for the manufacture of spiegeleisen and ferromanganese are sent to the smelters to be used for fluxing purposes on account of their content of iron and manganese oxides. The silver and lead present, however, are recovered during the smelting, while the iron and manganese pass into the slag and are lost.
Seite 286 - CARPENTER, GEORGE W. On the Mineralogy of Chester County, with an account of some of the Minerals of Delaware, Maryland and other Localities.
Seite 76 - ... specks grouped together into pockets. The hard ore consists of psilomelane in two forms — kidneys and irregular masses. The kidneys are very irregular in shape, varying up to 4 inches in diameter, though generally small, and are found scattered through the different clays and also through the soft-ore pockets. The irregular masses generally have botryoidal surfaces and contain cavities filled with clay. They vary in size up to a foot or more in diameter, and occur together in pockets or lenses...
Seite 280 - ... ton. Ores containing less than 40 per cent manganese or more than 12 per cent silica or 0.225 per cent phosphorus are subject to acceptance or refusal at the buyer's option. Settlements are based on analysis of sample dried at 212° F., the percentage of moisture in the sample as taken being deducted from the weight.

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