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Jan 1, 1955

Jan 1, 1961

By D. M. S. Bhatia, Richard D. Hagni

Five sulfide minerals from the Magmont mine, southeast Missouri were sampled for 31 trace elements in over 300 samples by laser microprobe spectrographic analysis of polished sections. The concentration of several trace elements shows a pattern of progressive variation with depth (space) and variation with different paragenetic stages (time) of each mineral. Factor analysis of the geochemical data shows sympathetic correlation both in space and in time of Bi, Cd, Ge, and Sn in galena and sphalerite, and Ni and Co in sphalerite and marcasite.

Jan 1, 1981

By Byron W. Cheever

At the meeting of the Institute held in St. Louis, in October, 1886 (Transactions, xv., 448), I presented a paper upon the above subject. From the well-known action of certain solvents on phosphide and phosphate of iron, the conclusion was then reached, founded on analyses, that phosphide and phosphate of iron must be present in all iron. But this conclusion was based upon the reactions obtained in the analyses of iron phosphide and phosphate, in which the phosphorus existed in conditions different from those found in commercial iron. In the former, the phosphorus is concentrated ; in the latter, diffused. This fact left a reasonable ground for doubting the existence of phosphoric acid in commercial irons. Some direct method was therefore sought which would prove its presence. After investigating the subject for some time, I came to

Jan 1, 1888

By M. P. Board, M. J. Reus

Instrumentation was installed during construction of the Silver Shaft in northern Idaho to evaluate lining behavior and rock deformation. Rock mass displacements were monitored with multiple-position borehole extensometers. Liner stress and strain were measured with concrete pressure cells and embedment strain gages. Rock displacement data from the 5,955-ft level indicate rock mass anisotropy. Liner stress and strain data reflect high in situ stresses and nearby station and raise construction. Continued monitoring and preliminary analysis indicate that concrete-lined, circular shafts are stable for high, unequal stress fields and anisotropy in deep level mines.

Jan 1, 1984

By J. R. Johnson

ZIRCONIUM'S corrosion rate by reactor fuel solutions increases with increasing reactor power. It is believed that the protective oxide film is affected by radiation damage. Observations of the

Jan 1, 1959

By Franklin H. Sharp

The operation of the Magmont Concentrator located on the New Lead Belt of Southeast Missouri is described. Ore characteristics affecting lead-copper-zinc separation are enumerated, and the cur- rent methods of separation are detailed.

Jan 1, 1976

By Karl Eilers

During my stay of two years in this country, I have heard of only four electric mine-locomotive plants, of which three were built by the firm of Siemens & Halske, and the fourth by the Allgemeine Elektricitatsgesellschaft, both of Berlin. The earliest of these was established in 1882 in the royal coalmines at Zaukeroda, Saxony. In 1883, the Consolidated Paulus and Hohenzollern colliery at Beuthen put in a plant; and in the

Jan 1, 1892

By John B. Pearse

The works heretofore used in carrying out the Bessemer process have been constructed substantially as follows: The whole works or plant has been divided into three parts. 1. The division in which the metals for conversion are melted. 2. The division in which the metals are converted into steel and cast into ingots, or the converting department. 3. The engine and boiler department which supplies the hydraulic power required to move the machinery, and which furnishes the blast used for converting the crude metal into steel.

By C. W. Baxter

Eveleth Taconite Co. was formed in 1963 to mine and beneficiate taconite on the Mesabi Range. Its Thunderbird mine is located mid-way between the cities of Eveleth and Virginia, Minn. The program for blasting restraints here is unique not only on the Mesabi Range but possibly in the world. The ore is a hard siliceous taconite. Its structure varies from bedded to massive with prominent vertical jointing. The jointing of the top or outcrop of the orebody is a challenge for the blasting practices as it is the source of an estimated 75% of the secondary breakage.

Jan 11, 1972

By John H. Puffer, Andreas H. Vassiliou

The Bemco mine area is within the Precambrian igneous and metamorphic rock terrain of the New Jersey Highlands province. Rocks In the area include a pyroxene granite, a hornblende granite, a quartz-oligoclase gneiss and a pegmatite and its host rock, a lens of amphibolite which becomes a sulfide-rich pyroxenite near the ore zone. The ore-bearing zone occurs along the hanging wall and foot-wall contact of the pegmatite which was emplaced discordantly into the amphibolite-pyroxenite.

Jan 1, 1985

NEW MEMBERS The following list comprises the names of those persons who became members during the period Oct. 10 to Nov. 10, 1915: Members BECK, WESLEY HUDSON, Civ. and Min. Engr., Ellsworth Collieries Co., Ellsworth, Pa. BRADSHAW, GRANT D., Pres., Andrews-Bradshaw Co, 409 Diamond Bank Bldg., Pittsburgh, Pa. BUTLER, BERT S., Geol U. S. Geological Survey, Washington, D. C. CAMERON, FRANK, Asst. Mine Foreman, Braden Copper Co., Rancagua, Chile, So. Amer. CHEN, YEFAH FRANCIS, Asst. Min. Engr., Pinghsiang Colliery, Pinghsiang-Ki, via Changsha, China. CLAGHORN, DAVID MONTGOMERY, Mining Engr., Timekeeper, Wilkeson Coal & Coke Co., Wilkeson, Wash. DAVIS, REUBEN WALDO, Min. Engr., Supt., Cannel Coal Co., Dolores, Webb Co., Tex. DOUTHETT, GEORGE M., Supt Crescent Metals Co., Glenwillard, Pa. DUNSFORD, ENSOR R., Min. Engr., Asst. Supt., Victoria Gypsum Min. & Mfg. Co., Ltd., Quarry, St. Alms. C. B.. Nova Scotia. Canada.

Jan 12, 1915

By P. H. Strickland, F. Lawson

It is now well established that in the majority of cementation processes used industrially, the rate of reaction can be described in terms of the mass transport from the bulk of the solution to the deposition sites on the metallic surface. Thus it should be possible to design cementation equipment from a knowledge of the flow situation in the equipment, and of absolute kinetic data. One way of obtaining such absolute data is by the use of the rotating disc geometry; this geometry is particularly suitable for a detailed study of cementation reactions. In spite of the similar mass transfer mechanism, cementation processes differ from other ionic transport processes in at least two respects. The presence of an attached deposit generally has a significant enhancing effect on the reaction rate; and side reactions involving oxygen and/or hydrogen ions can completely change the course of a reaction. Investigation of these peculiarities is necessary for a complete understanding of the process; since they cannot be isolated from the basic mass transport mechanism, close control of experimental conditions is essential. It has been found that the enhancement in deposition rate persists even when the deposit reaches a thickness several times that of the transport boundary layer thickness on the smooth surface. An explanation of the enhancement in reaction rate is proposed.

Jan 1, 1973

Jan 1, 1940

By A. J. W. Schwandt

Magmont is a venture jointly owned by Cominco American Incorporated of Spokane, Washington and Dresser Minerals, Division of Dresser Industries, Houston, Texas. Cominco American assumed direction of the operation in 1961 and completed exploration, preproduction planning and development, and is now the operating partner managing the operations. The plant has a rated capacity of 4200 tpd and produces in excess of 60,000 tons of lead per year. [ ]

Jan 1, 1970

Jan 1, 1920

By R. W. Raymond

AT the Liége meeting of the Iron and Steel Institute of Great Britain, in August, 1873, and also at the Vienna Convention of Mining and Metallurgical Engineers, at the end of August, and at the convention of German geologists, at Wiesbaden, in the first part * Extract from the President's address.

Jan 1, 1874

By Kwong Yung Kwang

This mine, which is sometimes called Tong colliery, from its director, Tong King Sing, is about 80 miles northeast of Tientsin (see map, Fig. 1). Fig. 2 shows a vertical transverse section through the coal-beds. These beds have a dip to the south of about 45' and are interstratified with sandstone, shale, indurated clay and fire-clay. Of the

Jan 1, 1888

By J. C. Mertz

ACCURATE knowledge of the solid solubilities of the elements that dissolve in the important base metals is needed for guidance in the preparation and heat-treatment of the alloys derived from these compo-nents. While there is still difference of opinion concerning the merits of the X-ray and microscopic methods of determining such solubilities, it is certainly true that the recent extensive use of X-ray diffraction to review the existing constitutional data has revealed many glaring inaccu-racies and has brought about a much improved knowledge of phase-boundary locations, which will inevitably come to include all of the important alloy systems. When the work is done with all necessary precautions it appears that in the majority of cases where the solubilities extend beyond a few tenths of a per cent the X-ray back-reflection technique is capable of furnishing the best of information in this field. For the most prolonged and thorough studies it is obviously advisable to combine the results of several methods, in particular, to obtain an agreement between X-ray and microscopic data. This paper reviews the work previously done on the solubilities of phosphorus, arsenic, antimony and bismuth in copper and, in considera-tion of the uncertainties thus made apparent, presents, new X-ray data obtained with the first three members of this group.

Jan 1, 1936

Man: A purely detached consideration of nature and the place of man in it may easily result in somewhat pessimistic conclusions as to man and his destiny. However, when we come to the evaluation of man's role in the development of natural resources and his achievements in this field, a more optimistic tone may be justified. Hence the possible contradictions between Man and Nature, Perfection, and the present chapter are more apparent than real. After all, progress must have a foundation of optimism, and we cannot challenge either the faculty or the students to better work and to a progressive and constructive outlook without an underlying tone of optimism and basic faith in the future. Geology is the basic science of Mother Earth; the science of the natural forces that have produced and modified the structure of our globe; the science of minerals and rocks; of landscapes and soils; of water supply and mineral resources, including mineral fuels; and of the history of life, both plant and animal, as revealed by fossils in rocks. It is difficult to reduce man and his historical significance to their proper relationship with regard to the earth and its history. Processes of rock formation have continued for at least two billion years; man's activities have been in evidence only a few thousand years. As a means of comparison, if the height of the Empire State building were to represent geologic time, the thickness of a nickel placed on the tower would just about repre-

Jan 1, 1950