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By William I. Rau

This presentation will examine the role commercial banks will be expected to assume in financing international minerals projects, including a discussion of various financing techniques such as project loans, production loans, and production payments. A discussion of the necessity for completion guarantees, finalized sales contracts, reserve evaluations, management contracts, and marketing undertakings in conjunction with financing availability are also included.

Jan 1, 1981

By AIME AIME

The name and address of the school are given first, followed by the length of the regular undergraduate curriculum, the degree granted, types of courses giben, and the name of the man in charge. This covers only work for the first or Bachelor degree in each case. The following abbreviations are used: B. Bachelor Cer. Ceramic. E. Engineer or Engineering Eng. Engineering or Engineer Geol. Geologist, Geological, or Geology M. Mines or Mining Met. Metallurgy or Metallurgical Mng. Mining Pet. Petroleum Ref. Refining S. Science Tech. Technology or Technical

Jan 1, 1939

By Fred Wright

IN A recent paper1 a detailed discussion is given of the possibilities. of using polarized light in the examination of opaque substances. The factors underlying the problem .are there treated from the viewpoint of the electromagnetic theory of light and the presentation is necessarily mathematical in form. The practical methods resulting from the discussion are, however, relatively simple and promise to be of value in the determination of certain ores and metals when studied in reflected light under the microscope. The results of the theoretical investigation referred to may be summarized by stating that in general the optical constants, such as refractive indices and absorption indices, cannot be satisfactorily ascertained on small, random, polished sections; that the use of polarized light enables. the observer ordinarily to determine whether the crystal plate is isotropic or anisotropic, and also to ascertain the degree of anisotropism; that for this purpose methods based either on the contrast in intensity between the two reflected components of non-polarized light, or on the amount of rotation of the plane of polarization, on reflection, of vertically incident, plane-polarized light, may be employed; that methods based on the phase difference between the two reflected components are in general of little value because of the small differences in phase which ordinarily result for a relatively large change in birefringence or biabsorption. The measurement of the optical properties of transparent minerals, even in minute irregular grains, is a simple task with modern petrographic microscope methods and is accomplished by petrologists as part of their ordinary routine work. But the determination of the optical constants of opaque substances is difficult and is rarely attempted; all observations are necessarily made in reflected light and are restricted commonly to the determination of color, of hardness, of the character of crystallization, and

Jan 2, 1920

By Leon Hart

THE nickel-chromium alloys of importance are those containing iron and those free from iron. The most important alloys containing iron, with regard to high tonnage, are the nickel-chromium steels. Straight nickel steel was introduced about the year 1889, but it was not until 1895, when it was found that the addition of chromium greatly increased the FIG. 1.-RESISTIVITY OF NICKEL-CHROMIUM-IRON ALLOYS. strength and resistance to shock, that nickel-chromium steels came into use. The three types of nickel-chromium steels developed at this time were: Type 1, containing 3.50 per -cent. nickel and 1.50 per cent. chromium; type 2, containing 2.00 per cent. nickel and 1.00 per cent. chromium; and type 3, containing 1.50 per cent. nickel and 0.50 per cent. chromium.

Jan 1, 1921

By M. O. Holowaty, C. M. Squarcy

Bituminous coal furnaces give way to coke, and by 1880, the American iron and steel industry was growing at a tremendous rate. In the twentieth century, the number of operating blast furnaces was cut in half while pig iron capacity more than doubled. Bituminous coal furnaces Attempts to relieve the shortage of charcoal by the use of bituminous coal in American furnaces began quite early. Use of bituminous coal in the blast furnace was restricted to areas lacking anthracite deposits but rich in deposits of bituminous coaL The largest concentration of bituminous coal furnaces was in Western Pennsylvania, West Virginia and Western New York state. Other areas included Kentucky and southern portions of the states of Indiana and Illinois. The first trials were made in Pennsylvania around 1780. Gradually several more furnaces began charging coal with their burdens as a partial substitution for charcoal. These so called cheaters were numerous, especially in Western Pennsylvania, which around 1810 began to expand its ironmaking capacity to catch up with the Lehigh Valley and the Schuylkill According to the existing references, complete bituminous coal burdens began to be used in this area only around 1840 when the ironmakers hastily adopted the hot blast apparatus introduced from England. The majority of these furnaces were built, however, after 1844 when an extensive experimental program, carried out at the Shenango Steam and Water Hot Blast Charcoal, Coke and Raw-Coal Furnace produced favorable results, with coal containing up to 35 pct volatile matter. The furnace was located near the Shenango River on the Lackawannok Run, five miles northwest of Mercer, Pennsylvania. It was built, owned, and operated by David Hogeland of Mercer. The first furnace was built in 1836 or 1837 as a charcoal furnace. Soon, however,

Jan 1, 1961

Jan 1, 1923

Jan 1, 1923

By E. A. Anderson, W. M. Peirce

Deflection in a corrugated roofing sheet under load may be considered to take place in two stages; an initial bending of the sheet under the load and a slow, permanent flow or creep under continued application of the load. Stresses great enough to produce permanent set when prolonged may produce apparent elastic deformation when applied for only a brief interval. It is impossible to set a time limit on the duration of stress in actual roof installations. Roofs in industrial locations where dust accumulations are heavy, as in cement plants, are often loaded continuously with

Jan 1, 1929

By W. M. Peirce, E. A. Anderson

Deflection in a corrugated roofing sheet under load may be considered to take place in two stages; an initial bending of the sheet under the load and a slow, permanent flow or creep under continued application of the load. Stresses great enough to produce permanent set when prolonged may produce apparent elastic deformation when applied for only a brief interval. It is impossible to set a time limit on the duration of stress in actual roof installations. Roofs in industrial locations where dust accumulations are heavy, as in cement plants, are often loaded continuously with

Jan 1, 1929

By E. C. Dominguez

INTRODUCTION The first commercial plant in the world to successfully produce pellets from manganese ore fines is the ICOMI pelletizing facility in northern Brazil. The main purpose of this paper is to describe the manganese pelletizing process that was developed through a cooperative R & D program by the Bethlehem Steel Corporation and ICOMI, i.e., Industria e Commercio de Minerios, S. A. The process combines heavy- media and gravity separation, reduction roasting, magnetic separation, and pelletizing on a straight-grate indurating machine. It produces high-grade manganese pellets from reviously unsalable low-grade ore fines at a rate of 20,000 tonnes (1) per month. The physical properties of the manganese pellets are comparable to those of iron ore pellets. The pelletizing plant, built at a cost of about 18 million dollars, is part of an ICOMI complex that includes manganese ore mining, an ore-washing plant, and railroad and port facilities, as well as two town sites. These two towns, one at the mine and the other at the port, each with complete community services, were built by ICOMI to serve the needs of over 1500 employees that operate the industrial complex. To give an idea of the magnitude of the investment represented by this complex, the cost up to 1957 to develop the mine and supporting services and social infrastructure was over 100 million dollars. It should be borne in mind that the above capital cost figures are in dollars of the years during which the respective projects were initiated and completed.

Jan 1, 1977

By J. E. Harris, J. A. Whiteman, A. G. Quarrell

The graphitizing reaction has been studied in a number of Fe-C-Si alloys in the temperature range 550° to 725°C. The TTT relationships exhibit "C" curve behavior except where nuclei, either foreign or graphite itself, are present before the start of the reaction. It is suggested that the rate -controlling process is diffusion of carbon through ferrite. For the reaction to proceed at the observed rate it is calculated that the matrix surrounding the particles must deform plastically; experimental evidence for this deformation is presented. It is well-established that the decomposition of austenite to pear lite occurs at a maximum rate at an intermediate temperature.l-5 This "C curve" be- havior, which has been reported in a number of other systems,5-10 is a consequence of the relatively low rate of nucleation of the pearlite at small degrees of undercooling of the austenite. The cemen-tite phase in the pearlite is, in turn, metastable with respect to graphite and if steels are held for prolonged periods at elevated temperatures decomposition of the pearlite occurs. It is difficult to predict the shape of the subcriti-cal graphitization TTT (time, temperature, transformation) diagram for, in this case, undercooling does not occur. However, the free-energy change for the reaction does decrease with increasing temperature" (Fig. 1) and it is thus anticipated that the rate of nucleation will fall as the temperature approaches that of the eutectoid. In addition, a decreasing growth rate with increasing temperature is predicted in some circumstances with pure Fe-C alloys. However, apparently similar conditions exist for first-stage graphitization in the austenite range (malleabilization) but no evidence for C curve behavior has been presented in the extensive liter-

Jan 1, 1965

By Nick Warren

The problem considered is that of predicting rock physical properties from observations of the structure of the rock. The approach here departs from previous studies in that both the physical properties and structural features are taken as statistical data and the relations between them are cast as statistical functions. This approach I have termed a "quantitative petrostructure analysis". This Paper deals with two aspects of making such a study; parameterizing patterns of topographic features of rock, and characterizing variables to allow correlation studies to be carried out. The principle of a quantitative petrostructure analysis is outlined and illustrated using maps from two samples of Conway granite.

Jan 1, 1982

By Michael Chender

The current outlook for financing new copper production is not very encouraging. At a time when companies are slogging through a protracted period of low prices as well as having to accept lower profits due to more stringent tax and royalty schedules, banks are beginning to require companies to take a greater equity interest in new projects. Mineral resource financing, including copper, seems to have lost much of its appeal to the lending institutions, and loans of any kind to many of the developing countries -from which over half of new copper capacity could be expected to come-are being examined much more critically than they were in the late 1960's and early 1970's.

Jan 12, 1976

By G. W. Healy

Activities of oxides in the ternary FeO-MnO-SiO system are calculated from data on the binaries, using the Gibbs -Schuhmann method. These activity data are used, together with thermodynamic relations, to calculate the contents of oxygen, silicon, and manganese in liquid iron, and the composition of the corresponding oxide phases in equilibrium with it. Excellent agreement was found between calculated and experimental metal compositions, indicating that thermodynamic methods, such as those presented, can supply useful data on slag-metal equilibria, and are therefore capable of wider application. When molten steel containing oxygen is treated with a deoxidizer, the product of the reaction is composed of the oxides of the deoxidizing elements together with more or less iron oxide. This assemblage of oxides is presumably very close to equilibrium with the melt since it is formed directly from elements dissolved in it. Therefore, it is likely that metal analyses corresponding to a given oxide phase composition are calculable with considerable precision where sufficient information is available on activities in both phases. The present study was made to test this hypothesis in the case of deoxidation by silicon and manganese. Here experimental data on the relationship among oxygen, silicon, and manganese in the metal phase are available, as are activity data for the MnO-SiO2, FeO-SiO2, and FeO-MnO binary systems. A further objective was to demonstrate in a specific example how gaps in the data may be filled by judicious interpolation, and how the Gibbs-Schuhmann method is applied to obtain activities in ternary systems. The rigorous derivation of the latter, requiring considerable facility in handling partial differential equations, tends to mask the real simplicity of the method, and repel the very engineers and experimenters who would benefit the most from its use. I) GENERAL PROCEDURE Deoxidation of steel with silicon and manganese results in the formation of two phases, metal and oxide. The number of components is four—Fe, Mn, Si, and 0. The phase rule then gives the number of degrees of freedom: If temperature and pressure are fixed, 2 deg of freedom remain. Consequently, it suffices to fix the concentration of two of the components of the system for all the concentrations to be determined and, at least in principle, calculable. The practical problem is then to discover a straightforward method of calculation with a minimum of trial and error solutions. The type of reactions to be dealt with are like the following: Si (in steel) + 2 O(in steel) = SiO2(in oxide phase) The standard free energy of this reaction is readily obtained from the literature, so that the equilibrium constant can be calculated by the expression: Since the metallurgist is concerned with percentages rather than activities, a real solution requires information that will permit activities to be converted to concentrations. This information is fairly adequate for the elements dissolved in molten steel, but is not available for the FeO-MnO-SiO2 oxide system. Therefore, the first step in this study was to find the relation between activity and concentration for the three oxides making up the system. The next step was the calculation of slag and metal compositions that are in equilibrium with one another. As shown by the phase rule, it is sufficient to assume the values of two composition variables in order to calculate the rest. But which two are picked makes a vast difference in how difficult the calculation turns out to be, so that it is necessary to make preliminary trial of several routes to find the easiest one. A convenient method is to begin with the slag, and to pick FeO concentration and that of one of the other oxides. Starting with the relation between oxygen dissolved in the liquid steel and FeO in the slag permits a good first estimate to be made of the oxygen content of the steel in equilibrium with FeO, because the iron content being fairly close to 100 pct, Fe has an activity close to unity. Using this first estimate of oxygen activity, approximate values of the manganese and silicon contents of the melt are readily calculated from the appropriate equilibrium constants. A minor correction for the depar-

Jan 1, 1963

By W. R. Seyfried

THE -problem of extracting alumina from clay and low-grade bauxites has been the subject of considerable interest for some time. The basic reason, of course, lies in the fact that known reserves of high-grade bauxite are not inexhaustible and that the present commercial process cannot successfully cope with low-grade bauxites or clay. Ultimately it may be necessary to use these poorer raw materials for all commercial operations, An unprecedented demand for aluminum during the war emergency and the constantly threatened shortage of imported bauxite caused the United States Government to take an active role in this problem. Through the National Academy of Sciences, the War Production Board and the Defense Plant Corporation, it investigated processes and finally selected four to be used in the construction and operation of four experimental plants. Each plant was to be designed in such a way as to facilitate its incorporation into a larger commercial plant should the need arise. The Chemical Construction Corporation process, or "Chemico" ammonium sulphate process as it is better known, was one of the four selected. The extensive literature and patents on record before the war generally follow one of two process-types depending upon the extracting reagent used. One group uses an acid reagent, the other an alkali. The Chemico process uses an acid reagent. For those interested in other processes described in literature, there is a short bibliography at the end of this paper, The basic steps of all acid extraction processes are: (I) to make the aluminum silicates acid soluble, (2) to separate the released alumina from impurities and insoluble gangue, and (3) to recover the reaent for re-use. THE PROCESS AS PLANNED In April 1941, a group of chemists and engineers of the Chemical Construction Corp, became interested in the problem of extracting alumina from clays and low-grade bauxites and, under the leadership of Mr. Blakeslee Barnes, Vice President and General Manager of the Company, first drafted a process in July of that year-five months prior to Pearl Harbor. The work continued in our research laboratories and with a small pilot plant, By June 1943, the work had progressed to a point where it was possible to apply for a patent on the process which was U.S. patent 2,405,426, granted August 6, 1946. Immediately prior to the development of the Salem plant, the process was envisaged to be as follows: I. The first step was to make the aluminum silicates acid soluble. It was planned: (a) Clay or low-grade bauxite would be roasted at 700 to 800°C (1292° to 1492°F). (b) The roasted ore would then be leached .with hot aqueous ammonium bisulphate to form a slurry. In this way the

Jan 1, 1948

By Graham Crutchfield

THE W. I. Cook pool in Shackelford County, Texas, has been the subject of a number of papers and articles. Its unique position both as to operation and development has made it an ideal location for unit repressuring. The major portion of the pool is located on the W. I. Cook ranch and most of the oil leases are owned by Roeser & Pendleton, FIG. 1.-PRODUCING SAND CONTOURS, COOK POOL, JAN. 1, 1931. Inc. and the Continental Oil Co. and operated by Roeser & Pendleton, Inc. The Humble Oil & Refining Co. and Tom James operate producing leases which have a vital bearing on the unity of the pool. Both have cooperated in the repressuring project. Practically the entire royalty is .owned by Mrs. W. I. Cook and she has given the operators her entire cooperation in all phases of unit repressuring.

Jan 1, 1931

several days before leaving Buffalo; influenza developed, and when his train reached Nashville, Tenn., he was too ill to continue his journey and was taken to the Kissam Hall Hospital, Vanderbilt University, where he died of pneumonia. He was a young man of unusual ability and high moral character, always brigh.t, happy and kind, faithful and honorable in all things; loved by both his associates and those under his authority. His life and character cannot be better described than by the following quotation from one of his superior officers: "Lieutenant Ohnsorg was a man loved by all of us, always cheerful, just and kind, with unusual executive ability. We can never expect to find a man who has his ability and fine temperament and his position can never be sled as he filled it." He was happily married and leaves to mourn his loss a wife, Constance E. (Rogers) Ohnsorg and a baby girl born since his death, Nov. 29, 1918, a father, W. H. Ohnsorg, mother, Ida May Ohnsorg, and a sister, Mrs. Stuart Strathy McNair. He was a member of the American Institute of Mining Engineers and of the Florida Phosphate Miners' Association. Lieutenant Edward Hale Perry At the height of the first great German'offensive -of'the Spring of 1918, Edward Hale Perry, of Boston, First Lieutenant, Company D, Sixth Regiment Engineers, U. S. Army, was killed on March 30, near War fusee—Aban-court, Picardy, France, while defending the Boisdes Tailloux against the terrific plunge aimed at Amiens. Lieutenant Perry was born in Boston, Jan. 23, 1887, the son of Georgianna W. and the late Charles F. Perry. After completion of his college preparatory course, he travelled for a year in South America and Europe before entering Harvard with the class of 1910. It might have been regarded as the natural thing for Perry, upon graduation, to choose a path that would lead to a business or professional career at home, but there were in his character a solidity, a horror of sham, a contempt for the "soft" things, and a love-of the open which caused him to be attracted to a life of stern and sturdy reality. Accordingly, he entered the graduate mining school at Harvard, and received the degree of Mining Engineer in 1913. In the meantime, two summers spent in Western mining camps had at-

Jan 1, 1920

By B. D. Cullity

AS methods for measuring fiber textures become more exact, it becomes justifiable to scrutinize an observed pole-density curve for evidence of minor texture components. These are disclosed by minor maxima or abnormally broad major maxima. One possible source of these minor components is twinning of the main component. In cubic metals and alloys, there are two kinds of twins: 1) Annealing twins in face-centered cubic metals. These are reflection twins on {Ill), and they can be expected to be present in recrystallization textures. 2) Deformation twins in body-centered cubic metals. These are shear twins on (112). Although usually formed only by impact, they might conceivably be present in the deformation texture of severely cold-drawn wire. Fortunately, both kinds of twinning lead to the same orientation relationships. It thus becomes possible to prepare a single list of angles between various planes in parent crystal and twin, which is helpful in examining pole-density curves for evidence of twinning in any cubic metal or alloy. Such a list of interplanar angles is given in Table I. This table consists of three parts, corresponding to the three major texture components—<100>, <110>, and <111>-most commonly found in the fiber textures of cubic metals. The table lists the angle between the pole of {hkl}, in either the parent crystal P or the twin T, and the fiber axis <uvu>. The crystals with <uvw> parallel to the wire axis are here

Jan 1, 1959

By E. J. Hall

(Butte Meeting, August, 1913.) THE iron-nail method of assaying has been used for a number of years, but has not met with the approval of all assayers. The method possesses advantages which may be given as follows : (1) no preliminary treatment is required ; (2) a lead button of proper size can be obtained (3) it is economical. On, the other hand, it has its disadvantages, which may be summed up as follows: (1) it is not applicable to ores containing large amounts of impurities other than sulphur, as practically all the base metals will contaminate the lead button ; (2) the slag is unsatisfactory in the larger number of fusions; (3) the method was known to give low silver results under certain conditions and the gold results were questionable. It was with the idea of determining the extent of this latter disadvantage that the following investigation was undertaken. It is well known that the fusion obtained in the lend assay is far more satisfactory than that in the " nails method " for gold and silver. The principal difference in the charges as a class is the presence of considerable reducing agent in the lead charge, and a limited oxidizing action in the nails charge, due to PbO. The possibility of improving the nails fusion by simulating the lead charge was the reason for using argol in some tests, even though there were reasons for expecting this would have -au objectionable effect on the results.

Jan 6, 1913

By Z. E. Arlin, R. D. Lynn

The problem of disposing of excess waste water coming from The Anaconda Co.&apos;s two uranium mills in Grants, N. M., first confronted the company&apos;s engineers in 1956. The increased discharge of mill waste water was due to the start-up of a second mill, recently completed to supplement production from a smaller plant which the company had operated since 1953. The waste water is mildly acidic and has a low level of radioactivity due to small amounts of uranium-natural, thorium-230 and radium-226. In addition, it contains large amounts of manganese, iron and the sulfate and chloride salts of sodium, calcium and magnesium.

Jan 7, 1962