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By F. J. Menzer, E. M. Schern

The Morenci/Metcalf porphyry copper mining operation, located in southeastern Arizona, currently processes approximately 91,000 tonnes of ore per day and has copper ore reserves estimated to be in excess of one bill ion tonnes. Functional groups within the Geology Department (currently staffed with six professional and two support personnel include mine geology, project geology, and hydrogeology. The primary task of mine geologists is daily preblast bench face mapping with grade and mill amenability estimates. Auxiliary duties include detailed in-pi t metal distribution evaluation, mineragraphic work and flux quarry geology. Project geologists conduct exploration and preliminary development projects both within and outside the Morenci district and provide support to ore reserve block modeling and geotechnical work performed by the Morenci mine engineering group. Hydrogeologists handle exploration for and development of groundwater resources and groundwater flow modeling, mine dump leach solution penetration and recovery evaluation, and tailing dam water reclamation.

Jan 1, 1984

By John Birkinbine

The press, trade publications, and special circulars, some elaborately illustrated, have been liberally employed within recent years in this country, to set forth the advantages of various locations as industrial centers, having as a basis the possibility of profitably producing pig-iron at these proposed centers: and special stress has been placed upon opportunities believed to exist at certain points for making iron of a quality suitable for the manufacture of Bessemer steel. The remarkable statements and prophecies made in some of these publications, have suggested the present paper, treating of the influence which location exerts upon the special industries named.

Jan 1, 1893

By Charles M. Cooley

With explosives representing over 10 pct of the cost of operating the entire company, the Maumee Collieries Co., Terre Haute, Ind., inaugurated a program to develop a low-cost blasting agent. Results of more than two years' work were announced on May 1 by Hugh B. Lee, president of the company. Utilizing a mixture of commercial-grade ammonium nitrate and carbon black packed in polyethylene bags, Maumee has been able to reduce blasting costs by 50 pct. The lower costs are brought about principally by elimination of high transportation charges on fixed explosives and use of low-cost material (commercial NH,NO, and carbon black). The Akremite blasting method incorporates a 20-lb cap-sensitive primer to detonate the stable explosive. Maumee now uses Akremite exclusively in its stripping operations producing more than 2 million tons of coal per year. The explosive is employed to break about 25 million cu yd of overburden that covers the coal

Jan 5, 1955

By P. D. Merica, J. R. Freeman, R. G. Waltenberg

Contents Page Constitution of Commercial Aluminum.................. 4 Solubility of CuAl2 in Aluminum at Different Temperatures........ 9 Effect of Magnesium on Solubility of CuA12 in Aluminum ......... 15 Solubility of Mg4Al8 in Aluminum at Different Temperatures........ 15 Solubility of Metals and Metal Compounds in Aluminum.......... 20 Summary and Conclusions......................20 Aluminum and its alloys have been the subject of much investigation1 during recent years, in the course of which the principal features of the constitution of most of the binary alloy systems with aluminum have been determined. Except in the case of a few metals—silicon, bismuth, cadmium, lead, zinc, and tin—an aluminum-rich compound is formed in each binary system, which forms a eutectic with the aluminum or its solid solution with this compound: Thus such compounds as FeAla, CuA12, Mg4Al3, and NiAls are formed, which are found in aluminum-rich alloys of their respective series as eutectics with the aluminum solid solution. These compounds are, in all cases, hard and brittle and their presence affects profoundly the physical properties of the alloys in which they occur. Within the zinc-aluminum system a compound, Al2Zn,, is formed that decomposes at lower temperatures. Silicon and tin each form a simple eutectiferous series with aluminum; bismuth, lead, and cadmium are only partly miscible in the liquid state with it. The extent of the solubility in aluminum, in solid solution, of these compounds or of the elements themselves, in the case of those series in which compounds are not formed, is of the greatest importance in

Jan 1, 1921

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 J. Dehais, W. A. Wallace

The pressures of urbanization are forcing producers of construction minerals either to transport their product greater distances or find new mineral sources. In areas with significant urban development near the coastal zone, offshore resources may prove to be an economically attractive alternative source. This paper addresses the economic viability of offshore mining of fine mineral aggregate. It proposes a model using a mathematical programming formulation based upon past research on both the onshore construction aggregate industry and the coal industry. The model is then used to assess offshore mining economics in the greater New York metropolitan area. Results show that in this region total consumer cost would be reduced by offshore mining of fine aggregate. In addition, increasing economies of scale could be realized by progressively larger mining operations. The distribution of these savings is also discussed.

Jan 1, 1982

By J. N. Roberts, K. V. Gow

In a recent review of the field of plastic deforrnation of metal single crystals, Maddin and chenl indicated the need for systematic investigations of the crystallography of the slip process with special attention to: a) The effect of the orientation of a crystal on the appearance of slip lines, b) The effect of high temperatures on the slip systems of aluminum, c) The effect of strain rate on the crystallography of slip. The present paper deals with the effect of temperature and strain rate on the mechanism of deformation of aluminum single crystals similarly oriented for single and duplex slip. The work of several investigators has shown that in aluminum at high temperatures other slip systems in addition to the predicted {I l l) <101> may operate. The most generally reported additional systems

Jan 1, 1959

By D. Turnbull, R. E. Cech

Small particles, 10-20 microns diameter, of a 28.6 atom pct nickel, balance iron alloy, have been supercooled 186 C with respect to bulk alloy M, temperature. Particles exhibit a marked mechanical shock sensitivity while being held in a supercooled state. The tendency for shock to induce martensitic transformation appears to be a maximum at —140 to —160°. Slow cooling of particles in mechanical contact with one another results in extensive martensite formation. This is prob-ably the same effect as the catalytic effect observed in polycrystals where martensite formation in one grain induces transformation in other grains. AS a result of extensive research over the past decade on the martensitic transformation, a much better though not complete understanding of the transformation has resulted. Recent reviews by Bilby and Christian&apos; and Kaufman and Cohen2 have

Jan 1, 1959

By Carl Zapffe

THE manganese ore reserves of Lake Superior, because of their location and nature, have recently achieved a marked degree of importance as compared with the world&apos;s manganese reserves. To appreciate fully the significance and the adequacy of this reserve, one should understand how such ores are used, where obtainable, the quantity used, possible avenues for increasing use or application, and the chemical and physical characteristics of the available ores. Only with that data at hand, is it possible to arrive at a convincing answer to the question whether the reserves of manganiferous iron ores are adequate to satisfy the annual demand of the presently known iron ores for the full life of the latter. That they should last is vital; and to ascertain whether they will last was the purpose of the present investigation, which marks the first attempt to study these Lakes Superior reserves. The Lake Superior region possesses and supplies the full assortment of iron ores needed for the conversion of ore into pig iron and steel ingots and castings. These ores are named bessemer; low-phosphorus and high-phosphorus non-bessemer, manganiferous and siliceous; and to include the term aluminiferous, would be in keeping with the most recent no men clature adopted by some dealers. About 35 or 40 years ago, perhaps less, most of the Lake Superior ore which is being used today was the material then considered either useless or too poor for immediate use; perhaps it was considered no more than a future reserve. An examination of the analyses of ores and the guarantees in the sales of those older times, convinces one that the opinions of those days must have been governed by only small differences in analyses. Some grades of ores used today in substantial amounts were used most sparingly only one or two decades ago. The relative quantities of the different ores used is ever changing; and, bit by bit, the metallurgy and the opinions are every changing and the prejudices against certain ores and practices decrease. This is unquestionably more pronounced for the manganiferous ores than for any other kind. If, when using the present data for manganiferous ores, we will only be

Jan 5, 1927

By B. B. Gottsberger

HAVE given considerable thought during the past year to the subject of licensing of engineers and par-ticularly to the position which the mining engineer should take on this question. I have found, however, that it is not a subject which yields much result for the thought expended on it. So far as any published record will show, mining engineers have been either ignorant of the extent to which the movement for the licensing of engineers has progressed or else indifferent to it. It is true that the Mining and Metallurgical Society of America, by a questionnaire sent out to its member-ship, did a great deal in calling this matter to the atten-tion of the mining profession, and so far as I know, the report of its committee, which analyzed the replies received, is the only published statement of the feelings and opinions of our branch of the engineering profes-sion. It is to be hoped that the conclusions shown by that report, namely, that mining engineers are almost unanimously opposed to the principle of licensing and consequently any legislation dealing with it, has received serious thought and that we are ready for an even more thorough consideration of the subject.

Jan 3, 1922

By D. W. Fuerstenau

This paper presents the results of an investigation of the stability of the mass flow rates and average pellet size in the different streams of an industrial-scale balling circuit. The variables in this study include water content, drum speed, and fresh feed rate. It was found that both the mass flow rates and pellet diameter are greatly disturbed when a change, positive or negative, in any of the variables takes place. For most of these disturbances to be damped down, a period of 1 hr or so is required. When a disturbance in the feed rate was made, the transient period extended to more than 1% hr (the duration of the experiment). It was observed that there is an interaction between the drum speed and moisture needed for producing an acceptable green ball product. The moisture content of the product pellets was found to be a function of the pellet size, with the larger pellets retaining a higher moisture content

Jan 1, 1983

As bizarre an example of competitive salesmanship to be imagined took place last June in Western Australia. A half dozen world renowned mining groups received a Japanese iron and steel investigatory mission. Geologists, engineers and businessmen, all specialists in iron ore, representing elements of the Japanese government and steelmakers, politely grilled each iron ore group for technical information and plans for property development. At stake were sales contracts with Japan for many millions of tons of iron ore. Since approximately two dozen visitors were involved, it was necessary to divide them into four groups for dispensing information, transportation and accommodations at the remote exploration camps. In a continent noted for its wide open spaces, the hinterland of Western Australia is spectacularly lacking in settlements. The state has better than one third of Australian land and statistically 0.8 persons per sq mile. In reality, however, over 400,000 of the 800,000 population reside in Perth. Under such circumstances, properly receiving and feting these important visitors would seem to be difficult but the competing exploration groups vied ingeniously to outdo each other in hospitality.

Jan 10, 1964

By Young C. Kim

Abstract-The use of computer models to design the ultimate open pit limits during feasibility studies as well as during long-range mine planning is becoming an enforced Practice in all types of mining, e.g., ferrous, non-ferrous, and coal. As a result, the state of the art in computerized ultimate pit limit design methodologies and associated computing and optimizing techniques has advanced considerably in recent years. Unfortunately, very little has been published to date regarding the preferred ultimate pit limit design philosophy, i.e., optimizing m satisfying, or regarding the modeling approaches being used for different types of orebodies. This paper reviews the current state of the art in various modeling approaches and optimizing techniques that are in use for different types of deposits, through available literatures and personal communications.

Jan 10, 1978

THOSE NOT MARKED ARE MEMBERS; MARKED THUS t ARE ASSOCIATES. HEAVY-FACED TYPE SIGNIFIES HONORARY MEMBERSHIP. JUNIOR MEMBERS ARE MARKED II. THE FIGURES AT THE END OF THE ADDRESS INDICATE THE YEAR OF ELECTION. AARONS, J. BOYD, Genl. Mgr., Chaffers G. M. Co., Boulder City, West. Australia. &apos;05 ABADIE, EMILE R., Min. Engr Box 291, Porterville, Tulare Co., Cal. &apos;76 ABBOTT, CLARENCE E., Genl. Supt., Iron Mines Div., 1405 Minnesota Ave., Bessemer, Ala. &apos;04 ABBOTT, J. W., Min. Engr., "St. Omer," 123 N. Grand Ave., Los Angeles, Cal. &apos;94 ABBOTT, Louis BENJAMIN, Chief Engr., Consolidation Coal Co., Elkhorn Div., Jenkins, Ky. &apos;15 ABBOTT, ROBERT R., Met. Engr., Peerless Motor Car Co., Cleveland, Ohio. &apos;12 ABE, ASAKA Yamagano G. M., Satsuma-Gori, Satsuma, Japan. &apos;14 || ABRAHAMS, A. I., Student 1391 Madison Ave., New York, N. Y. &apos;14 tACKER, E. O&apos;C., Met Bethlehem Steel Co., Bethlehem, Pa. &apos;86 ACKER, Louis K., JR., Min. Engr 565 Highland Place, Bellevue, Pa. &apos;08 ADACHI, JINZOO 11 Shiba Park, Shiba-ku, Tokyo, Japan. &apos;88 ADAMI, C. J., Min. Engr., St. Joseph and Doe Run Lead Companies, Bonne Terre, Mo. &apos;12

Jan 1, 1917

By L. C. Campbell

THE purpose of any accident-prevention program is the curtailment or entire elimination of injuries and fatalities. It is a job that is never finished in the coal-mining industry. Day by day, on shift and off shift, men are exposed to injury and death in varying numbers. Seldom is it possible to lock up at the end of the shift and leave a mine plant in the care of a sleepy watchman, as can be done at most manufacturing plants. Even on off shifts there are maintenance and supply crews, coal cutters, pumpers and ventilation men exposed to danger. The prevention program of The Koppers Coal Co. recognizes two primary facts: First, no program can be successful without the full support of the management and complete knowledge of the job at hand on the part of every supervisor. Second, and equally important, is the full cooperation of every employee in observing the safety rules and practices set up by the management. Conscious day-to-day concern for his safety by the indi-vidual worker is the longest stride toward a good safety experience. How to accomplish the education of the individual worker and super-visor for safety is the problem of The Koppers Coal Co. as it is the problem of all coal companies.

Jan 1, 1939

By W. J. Keep, Edward Orton

During the past two or three years consumers of pig-iron have been seeking more knowledge regarding the chemical questions involved in foundry-practice. This desire has been increased by the papers of Professor Thomas Turner, of Mason College, Birmingham, reporting a series of tests made to show that silicon is a useful, rather than a damaging element when present in proper quantities in cast iron, and that by its use pig-irons and scrap, which when used alone are totally unfit for foundry purposes, may be made to give satisfactory results. Professor Turner has shown that the strength of a cast-iron depends on : 1. The amount of weakening impurities present; 2. The proportion existing between the combined and the graphitic carbon in the cast-iron. He says that the tendency of combined carbon is to increase hardness and brittleness, while graphitic carbon makes iron soft, malleable and tough; too much of either form is a disadvantage; the strength depends on the proportion. Strength being the thing most desired, irons having an excess of weakening impurities will not find a market, and therefore the only thing to provide for is the proper proportion between combined and graphitic carbon. Professor Turner shows that by a judicious use of silicon this proportioning can be accomplished exactly according to the wish of the founder; an increase of silicon changing combined carbon to graphitic, and vice versa. When the founder understands its use he may soften and toughen, or harden and strengthen his

Jan 1, 1889

By John F. Barkley, J. W. Woomer, H. F. Yancey, H. B. Charmbury

The coal picture in 1955 was much brighter than in 1954, when the tonnage produced dropped to the 1939 level. Bituminous coal and lignite production are expected to approach 465 million tons, against 392 million tons in 1954, an increase of about 19 pct. On the other hand, the production of anthracite declined about 7 pct to some 25 million tons. There was marked improvement in coal consumption in all industrial lines except railroads. At the end of November 1955 the largest consumer, electric power utilities, had used about 126 million tons, an increase of some 22 million tons over the previous year. Coke-oven consumption increased about 19 million tons and coal coked in beehive ovens increased about 1.5 million tons, due to heavy coke

Feb 1, 1956

By Allen D. Garrison

THE chemistry of clays and shales has been assuming increasing importance in the petroleum industry, and two factors have greatly influenced this trend. The first has been the growing evidence that the marine shales are source beds, and that the petroleum compounds have migrated to the sand reservoirs overlying or underlying these shales: the second has been the demand for drilling fluids better adapted to penetrate these marine shales without difficulty and expense. ORIGIN AND GENERAL COMPOSITON OF CLAYS AND SHALES Clays, shales and surface soils are all closely related materials. They are mixtures of finely divided compounds formed during the weathering of the solid crust of the earth. Their nature is essentially colloidal; that is, their behavior is determined by the state of division of the materials and the surface reactions of the smallest grains. Many of their chemical changes affect only the exposed areas and do not involve the interior of the grains of matter. The extent of these reactions is more nearly proportional to the area of the substances than to their mass, therefore it is possible for a small amount of a material in an extremely fine state of division to completely dominate the character of the mixture. More than 83 per cent of the crust of the earth is composed of three elements-oxygen, silicon and aluminum. Consequently, the corrosion products of the crust are predominantly aluminosilicates, or compounds of aluminum, silicon and oxygen. If we add the compounds of six elements-iron, calcium, sodium, potassium, magnesium and hydrogen-more than 98 per cent of the crust has been accounted for. These six elements, together with the first three, also appear in soils, clays and shales. But direct chemical analysis is of little value in describing the nature of such materials. Many chemical individuals may be present in variable amounts, and the extreme subdivision of any one of the individuals may contribute qualities that dominate the mixture.

Jan 1, 1939

By S. L. Crouch, C. Fairhurst

The general term "coal mine bump" refers to the sudden and violent failure of in-situ coal. Coal bumps occur in most countries where coal is worked by underground methods. They are related to geological factors and mining techniques. Coal bumps can be characterized as unstable releases of energy associated with yielding that occurs with progressive mining. Unstable releases of energy occur when the coal is able to absorb less energy than is released by the surrounding rock mass during the yielding process. At any stage of mining, the amount of excess energy so released is governed by the mining geometry, the overburden stress, the elastic properties of the rock mass, and the stress-strain characteristics of the seam material. If the coal in the vicinity of the working face is crushed, the peak abutment pressure occurs at some distance into the intact portions of the seam, and mining takes place in essentially destressed coal. With subsequent mining, additional yielding occurs, excess energy may be released, and the peak stress is again shifted into the solid. This process continues until the mining geometry is such that the zone of peak stress is effectively surrounded by yielding coal, at which point it can be anticipated that further mining will produce dramatic redistributions of stress and be accom¬panied by large releases of energy. On this basis, the differences between several alternatives for mining a given block of coal may be pronounced.

Jan 1, 1975

[SWEETSER, R. H.: Discussions: on Evaluation of Coal for Blast furnace Coke, 94, 378, 394,385 on Mt. Union Sand Flotation Plant for Preparing Bituminous Coal, 74, 591 on Need for Research in Foundry Pig Iron, 76, 450 on Pig Iron Low in Total Carbon, Is in Demand for Use in Various Industries 75,471 on Properties of Coal Which Affect Its Use in the Ceramic Industry, 101, 254 on Relation of Ash Composition to the Uses of Coal, 74, 471 on Research on Blastfurnace Slags 100, 137.138 on Selection of Coals for the Manufacture of Coke, 74, 637 on Sinter in Blast-furnace Burdens, 100, 54 on Sintering Limonitic Iron Ores at Ironton, Minnesota, 90, 355, 356 on Slag Control in the Making of Iron and Steel, 116, 104, 115, 116 on Solubility of Nitrogen in Liquid Iron, 116, 193, 194 on A Statistical Analysis of Blast-furnace Data, 96, 70]

Jan 1, 1936