U.S. Geological Survey Professional PaperU.S. Government Printing Office, 1905 |
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Häufige Begriffe und Wortgruppen
altered amount Arizona Central Arizona Copper Company azurite basalt bluffs bodies brochantite calcite carbonate cent chalcocite chalcocite zone chalcopyrite Chase Creek chiefly chlorite chrysocolla Clifton concentrating consists contact-metamorphic contains Copper King Copper Mountain Coronado quartzite Cretaceous crystals cuprite deposits Detroit Copper Company diabase dike district dolomite Eagle Creek east elevation epidote fault feet wide feldspar fissure veins Garfield Gulch garnet GEOLOGICAL Gila conglomerate Gold Gulch grains granite Humboldt intrusion irregular kaolin lime limestone limonite lode Longfellow formation Longfellow limestone magma magnetite malachite Manganese Blue masses metamorphic miles mineral mines Modoc Modoc Mountain Montezuma Morenci Morenci and Metcalf northeast occur oxidation partly places porphyry porphyry dikes probably pyrite pyroxene quartz quartzite ridge rock Ryerson San Francisco River seams sedimentary sediments sericite shaft shale Shannon Mountain silica slope smelter stopes strata sulphate sulphides surface tunnel veinlets Yankie zinc blende
Beliebte Passagen
Seite 15 - Very respectfully, CW HAYES, Geologist in Charge of Geology. Hon. CHARLES D. WALCOTT, Director United States Geological Survey.
Seite 161 - Carbonic acid is only expelled when the siliceous impurities of the limestone are sufficient to combine with the lime set free, forming lime silicates.
Seite 101 - Central mine, in this district,1 200 feet below the surface, a vein of solid copper was found in sericitized porphyry. The vein formed a sheet of copper, in places 8 inches thick, standing nearly vertical. It had in places a fibrous structure, perpendicular to the plane of the vein, such as occasionally is exhibited by the chalcocite seams, of which it is believed to be a pseudomorphic development. In one specimen, according to Lindgren, two sheets of copper were found separated by sooty chalcocite....
Seite 336 - ... colored fruit, did lose a few berries. These vines appeared to be carrying too much fruit, still it was fairly well colored ; similar cases were also seen in Keuka Lake vineyards. The effects of overbearing are not limited to one season, but the plant may suffer for a year or two on account of the weak condition in which it was left at the close of the first, and it is not improbable that this weakened condition may be exhibited by the grapes shelling. Still, in visits paid to the vineyards of...
Seite 24 - ... deposits. A relationship is also clearly seen in the remarkable action of the vein solutions on the adjoining wall rock wherever this is limestone — tremolite and diopside being formed in it by replacement. On the whole, iron and silica are the main substances added during contact metamorphism as well as during the vein formation.
Seite 194 - Pyrite, magnetite, chalcopyrite, zinc blende, garnet, epidote, diopside, tremolite, quartz. Introduction of much iron and silica, together with copper, zinc, molybdenum, sulphur, possibly magnesia; elimination of carbon dioxide and probably some lime. Processes of oxidation: Limonite, malachite, azurite, cuprite, rarely native copper and chalcocite, copper-pitch ore, chrysocolla, goslarite, zinc carbonate, willemite, calamine, pyrolusite, quartz, calcite, chlorite, serpentine. Introduction of carbon...
Seite 185 - ... grains and little seams of the same mineral. The first constitutes high-grade ores, the second the low-grade. A residue of pyrite, not yet acted upon, is nearly always present. Thus a vein of massive sooty material cutting the shale in the Montezuma mine contained 96 per cent Cu2S and 2.4 per cent FeS>, and pyrite may be easily seen in nearly every specimen of low-grade porphyry ore. The pyrite first becomes coated with a black stain; in a more advanced stage the chalcocite penetrates the pyrite...
Seite 123 - ... The solution of a certain quantity of the original mineral caused the separation of a corresponding quantity of the ions of the replacing substance, according to physico-chemical laws. If carried out on these lines, the process is necessarily molecular and chemical. Where there were two solutions — one dissolving, the other depositing — and where a certain time intervened, the process is a mechanical one and should not, I think, be considered metasomatic. In many cases the distinction may...