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By AIME AIME

A CERTAIN area in the State of Indiana seems to be a breeding place for presidents and near president about eighteen miles southeast of Elwood is the little village of Daleville, and there, on April 9, 1890, John Robert Suman, newly elected President of the A.I.M.E., was born. It was not long before he migrated to California, however, where he went to the Los Angeles High School, then for two years to the University of Southern California, after which he went up to Berkeley

Jan 1, 1940

By I. D. Shah

A roasting procedure for synthetic copper sulfide which results in a reproducible transient melting at 450° and 470°C is described in this paper. Possible causes for this melting phenomenon are suggested, and also a procedure to avoid it during the roasting. This melting is believed to be responsible for the occasional occurrence of stickiness in the commercial roasting of copper sulfide concentrate. Many workers have studied the roasting of copper sulfides, but only Lewis et al. have reported that fusion and, in some cases, fusion with "boiling" occurred in the neighborhood of 450°C. The DTA and TGA apparatus, the materials used in this investigation, and the discussion of chemical reactions occurring during the CuS roasting are described in an earlier publication. CuS, in the form of either pellet or powder, was heated at 280° to 330°C in a flowing air or 30% 02: 70% N2 atmosphere. Heating was continued at this temperature until no further weight increase due to sulfates formation was observed on the TGA thermogram. This is believed to be due to the inability of SO, to diffuse out from the sulfate layer on the surface of the pellet, thus halting the sulfate-forming reactions. Hereafter, the sample oxidized in this manner will be referred to as "partially oxidized CuS." X-ray analysis and microscopic examination of a polished cross section of a partially oxidized CuS pellet showed the following order of layers starting from the center of the pellet: Cu2S, Cu2O, CuO • CUSO4, and CuSO4. A bare thermocouple inserted in the center of a partially oxidized CuS pellet (2.5 g) did not indicate any noticeable change in the temperature of the pellet when melted at 450° to 470°C in an inert or oxidizing atmosphere. During the preparation of a partially oxidized pellet, the temperature of a CuS pellet increased by 50°C due to the exothermic formation of sulfates in air at 320°C. The endothermic peak associated with the melting phenomenon at 450°C is shown in [Fig. 1.] A CuS pellet (0.2 g) was oxidized in flowing air (150 cc per min) at 10°C per min up to 320°C and held there for about 2 hr. Then, N2 replaced air and heating was continued up to 500°C. The exothermic peak at 320°C represents an overall formation of sulfates, and an endothermic peak at 450° to 470°C represents the melting phenomenon. To observe the melting visually, a small (50 mg), partially oxidized CuS pellet was heated (in static air) in a hot-stage microscope. The melting phenomenon was observed on an auxiliary TV screen. The sample

Jan 1, 1976

INTRODUCTION It has been impossible for the student, the practicing engineer, and the geologist to find all of the essential elements of mineral appraisal and mineral economic analysis in a single text. Indeed, the most recent texts on mine evaluation are over 20 years old. Many of the basic principles of mine sampling and evaluation have not changed over the ensuing years, but with the advent of the digital computer the entire scope of mineral evaluation has been expanded to encompass superior techniques that heretofore were not possible when using manual methods. The old manual methods for ore reserve computations and the techniques for assignment of area of influence to drill-hole samples are now as antiquated as the Model-T Ford. With the computer making possible solutions that had not been practicable in terms of time and effort, it is important for the practicing explorationist and mining engineer to understand many of the new concepts and principles that can be applied with the resolving power of the computer. Many practicing mineral industry professionals have been disappointed by certain computer programs and thus have some reservations about computers being able to solve their very real problems. Often the gap between the practicing engineer and the ivory tower theoretician applying modern computer techniques is too broad to be bridged with scattered, fragmented publications. PURPOSE AND SCOPE OF TEXT It is the intent of this book to update and to unify a great many scattered reference works used in the mineral industry today. The ensuing pages are addressed both to the professional already working in the mineral industry who needs information on computerized methods as well as to the serious student seeking to grasp the fundamentals and modern techniques of mineral appraisal and feasibility. These techniques are based on sound mathematical principles and theory, with the computer as a tool-but a very essential tool-for the solution of the problems involved. The computer can be of value only if it is programmed by those having sufficient expertise to use its inherent problem-solving capability, and the output is interpreted by those who are sufficiently acquainted with its operation to understand the data it produces. In the pages that follow the author intends to outline in considerable detail all the essen-

Jan 1, 1980

By Charles A. Thomson

RECENTLY a prominent Brazilian' doctor wrote to an American friend: "I feel that cultural relations between the American and Brazilian people could be promoted in a very speedy and effective way by establishing contacts between men of the same professions. . . . A Brazilian mechanical engineer could be immediately interested in relations with American colleagues, even if he had never heard of Longfellow and was not interested in Stokowski's orchestra. . . . A large number of cultural ties could be established between specific groups of men who have already some common interest, and who, whenever they meet, can do something that naturally brings them closer, that is, `talk shop."' In appointing a committee on Inter-American Engineering Relations to cooperate with the Department of State in its program of fostering cultural relations with the other republics of this hemisphere, the American Engineering Council has taken a step which should lead to a greater sense of unity and fraternity among engineers of the Americas. That such unity and fraternity are part and parcel of the moral defense of the hemisphere is obvious. For years engineers of the United States have been traveling South and South-east to construct roads and bridges, dam rivers, harness waterfalls, build ports, install and operate mining equipment, and erect buildings and plants, often at the risk of life. Those in the teaching profession in this country have had as pupils a growing number of students from our neighboring republics whom they have sent back home trained in the most efficient engineering methods. In a sense, however, these relations with the other nations on this side of the globe have been haphazard and left to chance. Personal acquaintance among engineers has played its role but no organized attempt appears to have been made to take advantage of the natural relationship which geographical and historical factors should encourage.

Jan 1, 1940

By Martin A. Moyers

THE nation's effort to win the war speedily is reflected in current trends in coal utilization, as in all other fields of our lives. In all industries, wherever coal is used for the production of heat and power the emphasis is on getting the most useful result with the least expenditure of matt.ria1. In addition to carrying its own share of the load, increased as it is by the demands of war industry, coal has had to fill in for the other fuels, mainly petroleum products, whose distribution from their more distant sources has been crippled by lack of shipping. Thus, the outstanding note in the utilization of coal this year is not the development of new methods of burning or handling coal but the extraordinary job that the industry has done in producing enough coal to serve all needs.

Jan 1, 1943

By P. LEROY FOSTER

G EOPHYSICAL prospecting was presented in its several aspects and discussed with much vigor at two sessions during this year's annual meeting of the Institute. The first session was devoted entirely to the presentation and discussion of various technical papers, while the second meeting took the form of a round table conference on the advisability of revising the existing mining laws to recognize the results of geophysical prospecting. This conference was immediately followed by further consideration of technical papers. Each session was well attended and great interest was displayed by everyone present.

Jan 1, 1929

THE progress in lead smelting practice in the United States during 1930 has been along previously defined lines. Since most of the material treated is high-grade concentrate relatively high in zinc, practically all the plants have been forced to adopt double sintering. This generally results in there being' no matte fall, and most of the copper in the charge is recovered in the furnace dross. The furnace dross is . smelted with. scrap iron and flux .in small reverberatories, giving a shipping matte or speiss high in copper and low in lead. Details of this reverberatory. furnace practice vary at the different plants. There is a decided tendency toward moreintensive filtration of blast- furnace and sinter fume. Bag capacity has been in- creased by using higher pressures and more frequent shaking.

Jan 1, 1931

By H. C. Babbitt

The Effect of Arsenic.—A question involving the temperature of precipitation of ammonium phospho-molybdate, which was brought to my attention some time ago, led to the following experiment :*

Jan 1, 1893

By H. A. Guess

AT the outset, said Mr. Guess, I may say that although I believe the present engineering courses in the various colleges and universities could be arranged to give the student within the same time limit a broader general education of un- doubted value, still I do not agree with the view held by many that engineers in comparison with those of other occupations-let us say doctors, lawyers, bankers, and so-called business men-seldom arrive at high executive positions. After all, we must remember that engineers are not very numerous as compared with the occupations just mentioned and therefore a lesser number reaching high executive positions stated numerically might be a larger number stated as a percentage. We all know there must be throughout the United States say three doctors to one engineer, but I don't think that even numerically there are as many doctors in high executive positions as engineers, and it is a fortunate thing for the country that doctors as a class are so busily engaged in alleviating sickness and suffering and in the advancement of medical science that they do not aim particularly for high executive positions.

Jan 1, 1926

By AIME AIME

AN unusual interest in the question of orienting the young college man in the mineral industry was shown in a well-attended session* of the Engineering Education Committee on Monday afternoon. About seventy-five employers and educators of mining engineers were present and took part in the discussions.

Jan 1, 1929

By Murl R., Schrock

THE use of diamond-drill holes at the Moctezuma Copper Co., Pilares mine, Pilares de Nacozari, Sonora, Mexico, for the ventilation of raises has resulted from experiments that were made in an effort to secure continuous and efficient ventilation in hot and gaseous raises. The method is particularly applicable in long raises and in raises run from development levels where the source of fresh air is distant. In order that the CO, concentration shall not become excessive, 30 cu. ft. per min. per man must be supplied to a heading for breathing purposes:' The quantity of air that will pass through a diamond-drill hole by

Jan 1, 1929

By P. E. Fitzgerald

SOME readjustments in the research programs of most of the oil companics and petroleum engineering schools have been made necessary by the war. The most obvious change has been the conversion from production engineering to problems more closely related to the nation's was effort. Many laboratories now devote much of their time to studies on products to be derived from petroleum. such as synthetic rubber, toluene, and substitutes for critical materials. Others are working to improve motor fuels including high-octane gasoline and the special lubricants required by the wide geographical range of the present conflict. Of great importance is the experience of the geophysicists, who are now devoting a great percentage of their time on instrument research and production or special apparatus required by the armed forces.

Jan 1, 1943

By AIME AIME

THE Wednesday morning session was devoted entirely to the consideration of the tentative code for coal mine ventilation. A. W. Hesse is chairman of this subcommittee. E. A. Holbrook presided at the session and assisted by A. W. Hesse and George S. Rice, gave the historical background of the movement for a ventilation code. They stressed the point that this was to be an engineer's code, and that it was hoped that it might serve as a valuable guide to operating companies in securing greater efficiency as well as safety in ventilation. The discussion was continued into the afternoon session, and by adjournment the entire' code had been covered.' Many sections were referred back to the Committee for further study and several new sections were suggested. The various opinions and new ideas brought out during the discussion proved very valuable and. contributed much to the progress being made in the preparation of this code.

Jan 1, 1929

By Carl L. Renzoni

INTRODUCTION This paper defines equity as the issuance of a permanent interest in the business on a broadly distributed basis. As such, it excludes the issuance of equity to either a merchant bank or to another corporation. Nearly twenty years ago the equity markets were very simple: The instruments used were primarily common shares, convertible debentures or convertible preferred shares. Another equity-type option often used, especially by junior companies, was the sale of joint venture interests. Issue sizes were generally in the order of $25 - $100 million and issues were syndicated primarily in North America and Europe by one or two investment dealers. Mining corporations today benefit from a market with much more depth. Issues are syndicated by dealers on a truly international basis, and issue sizes now often range up to $300 million. Moreover, dealers are now willing to take significant risk in buying the issues for redistribution. This discussion of trends in equity markets will encompass: 1) common shares 2) warrants to buy common shares 3) convertible debentures 4) commodity backed instruments A review follows of events that affect the mining industry and investment dealers as they have a bearing on the equity markets for the metal producers. FACTORS AFFECTING THE MINING INDUSTRY The current business cycle, up to October 1987, had been characterised by a buoyant stock market and depressed base metal prices. Mining companies entered this period with weak balance sheets and little prospect of cash flows meeting capital needs. The issuance of equity and the sale of assets were used extensively to reduce debt to manageable levels. During this period, the relative high price for gold, and more important, the very high earnings and cash flow multiples afforded to gold producers, caused companies to target gold as the only game in town. The need for capital to acquire and develop gold properties prompted an unprecedented volume of equity issues. (Burns Fry led or co-managed over $1 billion of mining equity issues per year during this period). This high demand for equity capital by the industry prompted an increase in the use of equity instruments, such as commodity backed instruments. In addition, government tax incentive programs in Canada, such as flow-through shares, allowed smaller companies to raise significantly more equity than would otherwise have been possible. Over $1 billion in flow-through equity was raised in 1987 alone. The abundance of flow-through capital in Canada made it easy to form a new company. One flow-through share fund developed a system of providing the working capital required for a company to be eligible to receive flow-through share capital so that an entrepreneur required only a mining property to get started. Many new companies were formed and several flourished in a buoyant stock market environment to the point that market capitalizations grew to $100 million or more. The current period is in stark contrast to that before October 1987. The equity markets are generally available to the resource industry only on a window basis and only for senior companies and for special situations. The industry is benefitting from buoyant metal prices, and bankers are anxious to provide debt capital. Investment dealers previously processing several equity issues

Jan 1, 1990

By E. J. Kenaedy, E. H. Robie

THOUGH the fall meeting of the Coal Division was held in the heart of the anthracite section, at Hazleton, Pa., the bituminous industry was well represented also, and the two groups found much common ground for discussion. The' technical part of the program was confined to two sessions in the morning and afternoon of the first day, Friday, Oct. 14, the evening and the following day being reserved for field trips and social functions. The attendance more than met the expectations of those in charge of the arrangements; there seemed no hint of depression here.

Jan 1, 1932

By AIME AIME

A REGULAR meeting of the Executive Board 'of American Engineering Council was held in the Onondaga Hotel, Syracuse, N.. Y., Feb. 14, 1921, with the president, Herbert Hoover, presiding. Reports of committees were presented and acted upon as follows: ENGINEER ON INTERSTATE COMMERCE COMMISSION The second meeting of the Committee was. called because it was represented to the Committee' on Pro¬cedure that the American Society of Civil Engineers, the American Association of Engineers, and the Ameri¬can Institute of Consulting Engineers were anxious to have President-elect Harding appoint an engineer to fill one of the vacancies on the Interstate Commerce Commission. The representative of The American Society of Civil Engineers agreed to endorse the recom¬mendations- of American Engineering Council, and the Committee on Procedure prepared and sent a letter to the President-elect, a - copy of this letter being sent to each member of the Board. No names were suggested. . The appointment of an engineer on the Interstate Commerce Commission was approved and the Board, after approving the action of the Committee 'on Procedure in writing the President-elect, voted that, if requested, the Committee on Procedure submit a list of not less than six names for the appointment of an engineer on the Interstate. Commerce Commission.

Jan 1, 1921

By Hans Lundberg

GEOPHYSICAL methods as described in technical articles generally fail to answer the questions of prospectors and geologists as to which method they should apply and what information they may expect from their application. This article is an attempt to discuss the use of electrical methods with special reference to the prospecting for orebodies and the map¬ping of geologic structure. Especially on virgin ground, geological reconnaissance should precede electrical prospecting, with the object of outlining carefully the orebearing rock and determining the possibilities of elec¬trical prospecting. No electrical survey will then be carried out on ground which, for geological reasons, may be considered barren or where the electrical meth¬ods are inapplicable. As the success of electrical prospecting depends on the difference in conductivity between the ore and the country rock within which the orebody is inclosed, the conductivity of the two should be considered and de¬termined, if possible. The conductivity of an orebody depends on the distribution of conductive ore minerals and, in addition, on its size (length, width and depth). Most minerals with metallic luster show good electrical conductivity; for instance, the sulfides. Zinc-blende is an exception, but as it is often associated with the ore minerals of good conductivity (for instance, pyrite or galena), there is likelihood also of finding zinc.

Jan 1, 1930

By F. F. Aplan

Pollution control will be of utmost importance in the 1970's. In this area, the mineral process engineer has a special competence to understand and remedy many pollution situations. There is an old adage that goes, "Build a better mouse- trap and the world will beat a path to your door." Would that it were so, but the reality of the situation is such that, just as a supplier must sell his machine, a professional man must sell his competence. It is a sad but true fact that mineral processing engineers have not done a very good job in selling their extensive competence in the control of a broad range of pollution problems. Recently one of our students visited a paper pulp mill where he was shown a foam fractionator used to remove paper pulp fibers from plant discharge waters. "Foam fractionator hell, that's a flotation cell!'' was his comment. Ah so, it would appear that large numbers of technical people consider themselves experts on "foam fractionation" Or is it that we have been very remiss in demonstrating the usefulness of our equipment and processes and our professional competence to solve, these pollution problems?

Jan 1, 1970

ABERDEEN, ESTHER, U. S. Geological Survey, Washington, D. C. ALLEN, VICTOR T., Director Geology Department, Institute of Technology, St. Louis University, St. Louis, Missouri. BATES, THOMAS F., Associate Professor of Mineralogy, Department of Earth Sciences, School of Mineral Industries, The Pennsylvania State College, State College, Pennsylvania. BOLGER, ROBERT C., Geologist, Pennsylvania Topographic and Geologic Survey, Harrisburg, Pennsylvania. BRIDGE, JOSIAH, U. S. Geological Survey, Washington, D. C. BURST, JOHN F., Geologist, Exploration and Production Research Division, Shell Oil Company, Houston, Texas. CAMPBELL, IAN, Executive Officer, Division of Geological Sciences, California Institute of Technology, Pasadena, California. FLINT, DELOS E., U. S. Geological Survey, Washington, D. C. FREDERICKSON, A. F., Associate Professor of Geology (Geochemistry), Washington University, St. Louis, Missouri. GLASS, HERBERT, Illinois State Geological Survey, Urbana, Illinois. GORDON, MACKENZIE JR., Geologist, U. S. Geological Survey, Washington, D. C. GRIM, RALPH E., Research Professor, Department of Geology, University of Illinois, Urbana, Illinois. HARDER, E. C., Aluminium Secretariat Limited, Montreal, Que., Canada.

Jan 1, 1952

By HOWARD N. EAVENS

DURING the year just closed the bituminous industry has been marked by a continuation of the period of low prices and a steady deflation, accompanied by the closing of mines and the consolidation of small units into larger ones. This pro- gram has marked almost every field in the country, and it bids fair to continue for some time. Some figures recently published for Kentucky show that in 1924 there were 660 mines producing 45,147,000 tons; in 1928 the number had decreased to 537, while production had increased to 61,860,000 tons, and a similar movement is occurring all over the country. Prices throughout the early part of the year were very low, but during the fall and winter the prices received are more satisfactory than they were earlier in the year. One of the leading developments in the marketing of coal during the year was the trade practice movement, which began in the Harlan field, and has now been adopted in the Harlan, Hazard, Appalachian, Logan. Williamson and Kanawha fields. The purpose of this movement is to prevent the shipment of coal except on order, and by the publication of price lists to prevent much senseless price quotation. Where it has been practised the longest this movement has resulted in a considerable degree of stabilization, and, undoubtedly, it will help existing conditions very materially if it becomes universal.

Jan 1, 1930