Economic Geology

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J. Wiley, 1916 - Geology, Economic - 856 pages

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Page 764 - 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.
Page 56 - They are made principally by rail over the international bridges and by lake and sea to the Canadian provinces. Exports are also made by sea to the West Indies, to Central and South America, and elsewhere. The imports are principally from Australia and British Columbia to San Francisco, from Great Britain to the Atlantic and Pacific coasts, and from Nova Scotia to Atlantic coast points.
Page 25 - Dry storage has no advantage over storage in the open except with high sulphur coals, where the disintegrating effect of sulphur in the process of oxidation facilitates the escape of hydrocarbons or the oxidation of the same.
Page 376 - Mineral Resources of the United States published annually by the United States Geological Survey.
Page 172 - Colluvial clays, representing deposits formed by wash from the foregoing and of either refractory or non-refractory character. C. Transported clays. I. Deposited in water. (a) Marine clays or shales. Deposits often of great extent. White-burning clays.
Page 796 - ... subjected. This left them in the right physical condition to be readily jointed and fissured by the contraction of the diabase. After the deposition of the cobalt-nickel arsenides, which seem to be among the first minerals deposited, the veins appear to have been slightly disturbed, giving rise to cracks and openings in which the silver and later minerals were deposited. Veins which escaped this later, slight disturbance contain little or no silver.
Page 315 - This addition is not as an adulterant, as was the case a few years ago, for it is now appreciated that the addition of barytes makes a white pigment more permanent, less likely to be attacked by acids, and freer from discoloration than when white lead is used alone.
Page 319 - FELDSPAR Feldspar is the name assigned to a group of minerals consisting of several species, all silicates of alumina, with one or more of the bases — potash, soda and lime. These species are divided into two groups, the potash feldspars and the lime-soda feldspars. The former group is by far the more abundant in North Carolina. Orthoclase and microcline whose composition is expressed by the formula K Al...
Page 274 - ... thickness, separated by thin beds of limestone or shale, in the series. Usually one and sometimes two of these beds .at a given section are workable, and probably some of the others will eventually be mined. The lime phosphate content in the workable beds varies from 65 to 80 per cent, with an average of 72 per cent.
Page 52 - ... DISCOVERY. Though La Salle in his hypothecated descent from the headwaters of the Allegheny to the Falls of the Ohio in 1669-703 would have passed by the eastern Kentucky coal field, he left no record indicating that he found coal during these explorations. To Father Hennepin,4 a French Jesuit Missionary, who in 1679 recorded the site of a "cole mine...

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