Search Documents

Jan 1, 1930

By K. R. Carson, J. Weertman

THE fatigue-hardening curve has received much attention in recent years. This curve is obtained by plotting the peak stress required to maintain a given plastic strain per cycle vs the number of cycles. It

Jan 1, 1969

By S. F. Ravitz, S. R. Zimmerely

High-grade cobalt concentrates were produced from the complex Blackbird ore with very good recovery in continuous pilot-plant operations in which a low-grade bulk cobaltite-pyrite flotation concentrate was roasted in a multiple-hearth furnace to oxidize the pyrite selectively. The cobaltite was floated from the resulting calcine.

Jan 10, 1950

By Christopher C. Barton

Each variable known to affect laboratory measurement of fracture-energy and fracture-toughness is reviewed. Specific examples are cited where each of the variables have been isolated.

Jan 1, 1982

Jan 1, 1961

By C. E. Shoenfelt

The outstanding development in Colorado in 1938 was the completion of the discovery well of the Wilson Crcek structure in Rio Blarlco County, on the western slope in the northwest corner of Colorado. Last year the Transactions (volume 127) carried an account of the discovery of oil in the Morrison sand in the Wilson Creek structure, in the joint test by The Texas Company and The California Company. This important

Jan 1, 1939

By R. H. Terhune

THE enormous production of pig-iron, together with the many difficult and interesting problems with which its manufacture is fraught, has secured to this industry the exclusive attention of scientists with reference to the chemistry of iron, while some of the minor departments of its metallurgy have suffered neglect. Particularly is

Jan 1, 1873

By C. E. Shoenfelt

The outstanding development in Colorado in 1938 was the completion of the discovery well of the Wilson Crcek structure in Rio Blarlco County, on the western slope in the northwest corner of Colorado. Last year the Transactions (volume 127) carried an account of the discovery of oil in the Morrison sand in the Wilson Creek structure, in the joint test by The Texas Company and The California Company. This important

Jan 1, 1939

Jan 1, 1929

Coal Division Industrial Minerals Division Minerals Beneficiation Division Mining, Geology and Geophysics Division OFFICERS AND COMMITTEES S D Michaelson, President J W Woomer, President-elect Elmer A Jones, Past President C E Lawall, Eastern Regional Vice-President G Donald Emigh, Central Regional Vice-President J D Forrester, Western Regional Vice-president R B Ladoo, Treasurer John Cameron Fox, Secretary

Jan 1, 1958

By H. M. Katz, J. L. Speirs, F. B. Hill

Jan 1, 1961

Jan 1, 1964

Jan 1, 1941

By Ronald D. Hill, Roger C. Wilmoth

The neutralization of acid mine drainage is becoming a common practice in the eastern United States. Over 200 plants are now in operation. Lime is the neutralizing agent utilized in most treatment plants; however, limestone may have an economic and practical advantage. Current research efforts of the Federal Water Quality Administration, both inhouse and through grants, to develop and demonstrate the use of limestone are reported. In essence, a state-of-the-art review is presented.

Jan 1, 1972

By William E. Ford, Edward Salisbury Dana

262. Parallel Grouping. - Connected with the subject of twin crystals is that of the parallel position of associated crystals of the same species, or of different species. Crystals of the same species occurring together are very commonly in parallel position. In this way large crystals, as of calcite, quartz, fluorite, are sometimes built up of smaller individuals grouped together with corresponding faces parallel. This parallel grouping is often seen in crystals as they lie on the supporting rock. On glancing the eye over a surface covered with crystals a reflection from one face will often be accompanied by reflections from the corresponding face in each of the other crystals, showing that the crystals are throughout similar in their positions.

Jan 1, 1922

Jan 1, 1914

In the four articles presented on the following pages, a panel of comminution experts offer readers the benefit of their experience with autogenous grinding and forecast some of the future developments to be expected in this fast-growing field. The articles are based on an AIME panel discussion in which the authors participated.

Jan 1, 1970

It appears that Utah is about to add another mining district to its already impressive roster. This time it is the Great Salt Lake, whose high-mineral content waters are being subjected to intensive study aimed toward the recovery of potassium, magnesium and lithium compounds by solar evaporation techniques. Among the firms conducting such experiments is Lithium Corporation of America, which, in a joint venture with West Germany's Salzdetfurth A.G., is operating evaporating ponds and running engineering tests at a site near Little Mountain, about ten miles west of Ogden. Here, on the clay flats along the northern portion of the lake, LCA holds leases and options totalling about 55,000 acres in the Bear River Basin.

Jan 7, 1966

By Richard Pearce

WHILST most of the silver- and copper-bearing veins of Butte have characters somewhat similar, the Gagnon vein has certain rather remarkable features which are not noticed in any of the other mines. The silver-veins proper, as illustrated in the Alice, Lexington, Moulton, and many others, have certain well-known typical characters. Manganese is always present in variable quantities as rhodocrosite or rhodonite, associated with quartz, pyrite, and sphalerite, and with little or no copper. The copper-veins also have certain mineralogical characteristics, which are very similar, or different only in minor points. Chalcocite, chalcopyrite, bornite, enargite, with variable quantities of pyrite, may be said to represent the general mineralogical features of these lodes. It is worth noticing that while the silver-bearing lodes have more or less sphalerite, this mineral is almost entirely

Jan 1, 1888

In the seven years that have elapsed since the AIME World Symposium on Mining and Metallurgy of Lead and Zinc, there have been a number of significant milling innovations and trends implemented in lead-zinc flowsheets to either improve grade and recovery or to control escalating mill costs. First, mill controls and instrumentation, which only had a foot in the door in 1970, have become increasingly common. In Australia, research into automatic crushing control has been implemented by Mount Isa Mines, and in virtually any large lead-zinc mill worldwide, an assortment of on-stream x-ray analyzers, grinding circuit controls, level detection devices, and reagent metering methods can be found. The increased circuit control offered to mill operators by this new technology points to more efficient flowsheets, as well as to a greater dependence upon computer-controlled operation.

Jan 11, 1977