The Mining World, Volume 32Mining World Company, 1910 |
Outras edições - Ver tudo
Palavras e frases frequentes
acid Amalgamated April April 16 Ariz assays average Butte camp Capital carbonate chalcopyrite City claims coal Cobalt Colo copper cost creek crosscut cyanide deposits depth district Dividends drift drill electric engineer equipment eral factor of safety feldspar furnace galena give gold grade graphite gray copper ground Guanajuato high-grade Hill hoist hole Idaho illus installed iron Kerr Lake Lake lead lease located lode long ton luster machinery ment metallic Mexico miles mineral Mining World Mont month Name of Company Nevada North opened operations oxide plant production pyrite quartz reported rhyolite rock sample schists shaft shipments shipped silica silver slag smelter smelting specific gravity stamp steel stope streak sulphide surface tests tion Tonopah tons Total tube mill tunnel Utah vein week York zinc Zincite
Passagens conhecidas
Página 886 - That every person above the age of twenty-one years, who is a citizen of the United States...
Página 887 - Interior, be, and is hereby, authorized and directed to perform, or cause to be performed, any and all Acts and to make such rules and regulations as may be necessary and proper for the purpose of carrying the provisions of this Act into full force and effect.
Página 957 - Document No. 465, above referred to, shows the quality of the Oklahoma gypsum. The quality of the Kansas gypsum is shown by an analysis of a sample of crude gypsum taken from the quarry of the Best Brothers Keene's Cement Company, at Kling, Kans., and was made by the Bureau of Standards of the Department of Commerce and Labor.
Página 690 - ... considers deserving. During the year 1909 more than $7,000 was distributed gratuitously in this way by the American Steel & Wire Co.
Página 958 - A number of pegmatite deposits of coarse grain are rendered worthless for pottery purposes by the abundance of one or more of these iron-bearing minerals. The presence here and there of minute flakes of white mica (muscovite) is characteristic even of the highest grades of commercial feldspar, and chemically this mineral is not injurious. It is, however, exceedingly difficult to pulverize the thin, flexible mica plates to a fineness equal to that...
Página 886 - Act a prospecting permit, which shall give the exclusive right, for a period not exceeding two years, to prospect for oil or gas upon not...
Página 835 - Where necessary the levels may be extrapolated, as on the extensions of lines 8-16 and 12-18, but points so located are, of course, not so reliable as the interpolations. They aid, however, in obtaining the general direction of the contours, and as the seam has been eroded at these points great accuracy is not needed. In this way a series of points of equal elevation are obtained for both sides of the depression. The auxiliary lines, such as...
Página 833 - B" side of the line? The drifts 1, 2, and 3 are presumably horizontal, and since they lie in the vein they are parallel to the strike. In the endview they will appear as !„, 2v, 3K, and will determine the endview of the vein, the vertical shaft, B, appearing at Bv B'v.
Página 958 - The requirements of the potter's trade demand that in general the percentage of free quartz associated with the feldspar used for this purpose shall not exceed 20 per cent in the ground product, and certain potters demand a spar which is nearly pure, containing probably less than 5 per cent of free quartz. In order to be profitably worked, in most feldspar mines between one-fourth and one-half of the total material that must be excavated should contain less...
Página 958 - In order that a deposit may be worked profitably these minerals, if present in any appreciable quantity, must be so segregated in certain portions of the deposit that they can be separated from the spar without much more hand sorting and cobbing than is necessary...