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Covering resources, production, uses, defense impact, and future outlook of nickle, Mining Engineering presents the third in a series of articles on strategic minerals. Preceding it are "Cobalt" in January and "Sulphur" in May.

Jan 8, 1951

By D. W. Brunton

The object of the investigations and experiments here recorded was to obtain such information and data as would make it possible to determine the fineness to which crushing must be carried, in sampling gold- and silver-ores, in order to obtain results within an allowable limit of error.

Jan 1, 1896

By R. W. Ells

That portion of Quebec to which the few remarks I propose to make are more particularly intended to apply, viz., the Eastern Townships, has long been known for its mineral wealth, and has enjoyed a reputation for mining enterprises, second probably to no other part of Canada. Capital has been invested in large amounts at various points, some of which has yielded a handsome return to the investors, while in other cases the inevitable results of rash and foolish speculation have followed, much good money has been sent after bad, and the principal result has been a dearly bought expe- .

Jan 1, 1890

Jan 1, 1920

Jan 1, 1920

By C. R. Sundeen, C. W. Nicolson, J. D. McAuliffe, C. A. Campbell, P. D. Pearson

SHAFT SINKING SYMPOSIUM is a weighty term that could mean any number of things. However, in, this case it has been possible to utilize the transcription of the Annual Meeting Session of the same title and present it in much the same manner as the experts on the panel presented it to their audience Wednesday afternoon, February 18, 1953, at the Los Angeles Statler Hotel.

Jan 8, 1953

SEC. 1. The membership of the 'Institute shall comprise six classes, namely: 1. Members; 2. Honorary Members; 3. Senior Members; 4. Associates; 5. Junior Members; 6, Rocky Mountain Members. All shall be equally entitled to the privileges of membership, excepting that no member of any class whose residence shall be outside of the United States of America, except those residing in Mexico and Canada, shall be entitled to vote. SEC. 2. Members: A person to be eligible for election or transfer into the class of Member must be at least 27 years of age and must have had at least six years' employment in the practice of engineering, mining, geology, metallurgy, or chemistry, during at least three years of which he must have held positions of responsibility in one or more of these fields. This shall not apply to Rocky Mountain members.

Jan 1, 1932

By H. E. T. Haultain

The study of rock crushing or grinding in tube-mills is difficult on account of the large size of the units employed in the field and the large number of variables entering into the problem. Three or four years ago, in the laboratory of the Department of Mining Engineering of the University of Toronto, a serious effort was commenced to study the matter under laboratory conditions. Experiments were carried on in a cylindrical tube-mill 18 in. long and 12 in. in diameter, inside measurements,

Jan 1, 1923

By Owen S. Roberts

During the design phases of a conveyor system, the question arises regarding the type of drive required for each application. The paper shows that the correct drive for any particular application is the one that satisfies the criteria established for that application in the most economical manner consistent with such considerations as site location, availability of spare parts, area environmental conditions, power supplies available, etc. Following discussions of various mechanical arrangements for the drives, motor types and their characteristics are considered along with the control means of modifying these characteristics to satisfy individual requirements. These characteristics are all illustrated graphically. After selecting the motor and its starter, control accessories and interlocking arrangements as applied to material handling systems are discussed.

Jan 1, 1973

By H. H. Haung, J. D. Miller, E. F. Pereira

The chemistry of copper extraction from ammoniacal solutions by hydroxyoxime extractants was studied Equilibrium measurements were made by shakeout experiments with subsequent analyasis of the aqueous and/or organic phases The kinetic experiments were carried out in a single drop reaction cell in order to establish the details of the intrinsic reaction kinetics for this system. Equilibrium measurements Indicated that the extraction involves complete displacement of ammonia ligands from the coordination sphere of the cupric ion by the extractant molecules The extraction reaction has the following stoichiometry

Jan 1, 1981

By R. W. Armstrong, P. C. Jindal

TABOR1 has indicated for a number of polycrystal-line materials that their hardness should be directly related to their yield strength. For a material showing zero work-hardening, the Meyer hardness, MH, may be calculated in terms of the yield stress, sy, by utilizing slip line theory and the result is: The Meyer hardness corresponds to indenting the surface with a spherical indenter and specifying the ratio of load and projected area of the indentation. The correlation indicated by Eq. [I] is not well-established. It has been verified to some degree by performing hardness tests on materials strained to the maximum nominal stress and taking this stress as the (new) yield stress of a nonwork-hardening material. The dependence of hardness on yield strength for an annealed material capable of showing work-hardening has not been theoretically evaluated but, presumably, the hardness should be greater than that specified above. Marcinkowski, Fisher, and szirmae2 measured the dependence of the Vickers Diamond Pyramid hardness, H,, on yield strength for an annealed Fe-Cr alloy which shows work-hardening and found:

Jan 1, 1968

NEW MEMBERS The following list comprises the names f those persons who became members during the period of Dec. 10, 1917, to Jan. 10, 1918. ARLUCK,- A. A., Headquarters Co., 66th Artillery Brigade, 41st Division, Care Postmaster, New York, N. Y. BUCK, LEONARD J Park & Prospect Ave., Bethlehem, Pa. BULL, FREEMAN N., Min. Engr., Robert W. Hunt & Co., 310 Wall St., Joplin, MO. BURGESS, ELISHA PAYNE JEWETT, Pres. & Mgr., Montana Consolidated Copper Co., Care Clark Dodge & Co., 51 Wall St., New York, -N. Y. CAMPBELL, THOMAS E Governor of Arizona, State House, Phoenix, Ariz. CARTWRIGHT, F. 0., Asst. Chief Clerk, The Braden Copper Co., Bancagua, Chile. CASH, FRANK E., Engr. & Asst. Supt. of Mines, Alleghany Ore & Iron Co., Lignite, Botetourt Co., Va. CRITCHLOW, EDWARD B., Pres., Conkling Min. Co., 307 McCormick Bldg., Salt Lake City, Utah.

Jan 2, 1918

By A. Bleier, E. D. Goddard, R. D. Kulkarni

The influence of the collector structure on the amine (RNH2, R=alkyl) flotation of quartz has been systematically investigated using a modified Hallimond microflotation cell. This study focuses on the effect of varying chain length, branching in the alkyl group R, polyfunctionality of the collector molecule, and alkyl substitution on the nitrogen atom. In addition, adsorption at the solution/air interface and electrokinetic results for the solid/solution interface were employed to further elucidate the role ad the interrelation of the structural parameters in the flotation process. Estimates of an electrical double layer attractive energy between the bubble and the solid particle are made.

Jan 1, 1976

By D. A. Hinckfuss

The large and compact but simple Bougainville Copper Limited flotation circuit has been in operation for 3-1/2 years. Discussion of problem areas encountered since start-up and remedies that have been implemented or proposed, form the main basis of this paper. Full current operational data is also provided.

Jan 1, 1976

By R. L. Braun, D. L. Leach

Laboratory experiments simulating in-situ copper recovery from primary sulfide ores in sulfuric acid systems pressurized with oxygen are reported. Copper extraction and acid consumption data are correlated with temperature in the range 50 to 150°C and quenched pH in the range 0.25 to 2. Adverse changes in the chemical composition of the leach solution and the formation of gangue-mineral alteration products and secondary sulfides can severely limit the extraction of copper above 90°C. Keeping the pH below the self-buffered value of about 2 and the temperature below about 110°C produces the maximum extraction rates. Forcing the pH too low not only results in excessively high acid consumption but may also limit the extraction of copper at temperatures above 100°C.

Jan 1, 1977

By John Patek

KNOWLEDGE of the relative floatability of silicate minerals is increas-ing in importance as flotation is being applied to the concentration of nonsulfides. Many silicates are in themselves commercial products amenable to concentration by flotation. Moreover, the selective flota-tion of other nonsulfide minerals, such as cassiterite, depends largely upon the floatability of associated. gangue silicates. Differences in floatability existing between the various silicates have not been suffi-ciently appreciated; for example, the feldspars that differ greatly in floatability have generally been merely treated as "feldspar." It was the purpose of the work described in this paper to determine by experi-ment the differences in floatability between silicates; to investigate the causes for such differences, and to discover a means of predetermining approximate floatability without the necessity of experimentation.

Jan 1, 1934

By H. E. T. Haultain

The study of rock crushing or grinding in tube-mills is difficult on account of the large size of the units employed in the field and the large number of variables entering into the problem. Three or four years ago, in the laboratory of the Department of Mining Engineering of the University of Toronto, a serious effort was commenced to study the matter under laboratory conditions. Experiments were carried on in a cylindrical tube-mill 18 in. long and 12 in. in diameter, inside measurements,

Jan 1, 1923

Jan 1, 1919

By Robert F. Winkle

A detailed breakdown of mining costs, available to management on monthly and year-to-date bases, is mandatory for a controlled and efficient mining operation. A simple lump sum reporting of costs may indicate a profit or loss differential, but it does not allow an effective search for areas of possible cost reduction. Moreover, functional reporting is necessary on a timely basis so as to note trends of increasing costs In specific areas, which in turn allow possible preventive action by management. Definitive cost information helps to eliminate the tendency to overlook areas where cost Improvements can be made. A good cost control system points out salient operational weaknesses by: ( 1 ) allowing comparison of functional costs with similar costs of other mines and (2) pinpointing sudden increases over unit empirical costs within the organization. In general, the cost accounting structure is relatively uniform within large open pit mines, but surprisingly some systems will overlook the need for detailed breakout in comparatively high cost areas. In some other systems, unrelated costs will be lumped together, preventing careful analysis of cost accrual.

Jan 1, 1979

By R. N. Woody, S. J. Work

Crushing development at Duval Corp.'s Sierrita concentrator in Sahuarita, Ariz., has been a continuing effort since plant startup in January 1970. The original crushing system was designed to produce 65 000 t/d (72,000 stpd) of ore. However, in the summer of 1970 the Sierrita plant was averaging only 43 000 t/d (47,000 stpd) due to coarser than expected secondary crushing plant feed, lower than design crusher operating availability, and inability to achieve design tertiary crusher power draught at an acceptable hydraulic support pressure.

Jan 4, 1979