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By Herbert E. Hawkes

“For his Pioneering leadership in the science and technology of mineral exploration, especially in the development and world-wide application of geochemical methods as major exploration tools, and for his lecture ‘Geothermal Hydrogen’.”

Jan 1, 1981

The Library of the above-named Societies is open from 9 A.M. to 10 P.M., except on holidays. It contains about 70,000 volumes and 90,000 pamphlets, including sets of technical periodicals and the publications of - scientific and technical societies members of the Institute, with few exceptions, are forced to spend a portion of their time 'in localities isolated from sources of information. To these the Library, through its Library Service Bureau, can render - valuable service through correspondence; letters requesting information will receive especial attention. The Library is prepared to furnish references and photographic copies of articles on mining and metallurgical subjects; to determine the existence of mining maps, and to furnish genera1 information on the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape.

Jan 10, 1916

By K. Y. Lo, R. S. C. Wai, R. K. Rowe, L. Tham

Laboratory tests for the determination of thermo-mechanical proper- ties of three rock types were performed at temperatures up to 400°C. Results showed that for the medium and coarse Granitic Gneisses, the coefficient of thermal expansion and Young's modulus are strongly temperature and temperature history dependent. A threshold temperature exists for each rock type above which material nonlinearity becomes important, and is associated with the progress of thermal cracking. Finite element computations were performed to illustrate the influence of material nonlinearity and boundary constraint on thermal stresses. Finally, a case history of thermal spalling was analyzed and it is shown that the results of analysis are consistent with field observations.

Jan 1, 1982

By Theodore Barry

The task of developing controls in the mining and manufacturing industries to give them a tighter grip on operating costs has afforded this author an interesting vantage point for observing certain practices common to both industries. Of course, each of these industries has problems unique to itself, but all industries have many common problems. After all, every industry is a business and every business is concerned with the task of producing its wares as profitably as possible. While many differences between businesses in different industries are known, the author is convinced through experience that the mining industry has much more in common with the manufacturing industry than is generally acknowledged. Four principal questions come to mind in the comparison of mining with manufacturing: How different are the management control methods in these two worlds? How do both industries go about the task of controlling costs? How does the mining industry compare in terms of the effectiveness of its workers? And perhaps most important, what can the mining industry learn from what the manufacturing industry is doing?

Jan 11, 1962

By Charles E. Mauk, H. William Prengle, Robert W. Legan

A process breakthrough was needed for the complete destruction of total cyanide influent as high as 100,000 mg per 1, or below 1 mg per 1, to produce an influent with total cyanide below the limit of detection. The process uses ozone for the total destruction of cyanide and metal cyanide complexes. It was found that while ozone alone reacted with the iron cyanide complexes too slowly for practical application, ozone at slightly elevated temperature became more effective, and ozone with ultraviolet light became effective enough to permit the design of a successful system.

Jan 1, 1977

By L. Massé, Th. Koulomzine

NOTE ON HAALCK'S FORMULA QUANTITATIVE interpretation of magnetic anomalies is admittedly a difficult process. Few authors have attempted a general approach to this problem. A [ ] number of publications can be found widely scattered through scientific periodicals, which present particular solutions obtained by the introduction of simplifying assumptions, such as the reduction to an equivalent magnet or pole, or the hypothesis of a very thin vein. The practical applications of these solutions are necessarily very restricted though they have given satisfactory results in isolated cases. Probably the most widely known equation of this type was given by Haalck.l His classic work contains curves calculated for typical conditions, and has now become a standard reference. However, a close scrutiny of Haalck's derivation reveals that, aside from the hypothesis of a thin vein, it rests on the

Jan 1, 1947

By H. R. Joesting

Geophysical search for minerals is stepped up to meet requirements of expanded defense program - Seismic and electrical surveys become firmly established for ground-water and engineering investigations.

Jan 2, 1953

By A. D. McMaster, M. L. Gimpl, N. Fuschillo

There is interest in the use of rhenium metal films as resistive elements in thin-film circcits, and already some zvork has been done using er)aporated rhenium films. It has been found that rheniim films protected from the atmosphere by an evaporated layer of silicon monoxide show excellent electrical stability. Unprotected films, however, are subject to aging- effects, notably the increase in electrical resistivity as a function of time. This phenomenon can be understood as primarily one of oxidation of the thin films. This paper is concerned with the study of the oxidation and crystallization behavior of such unprotected films. It has been found that the oxidation rates are a function of the substrate temperatures used during the deposition of Lhe metal films. The strictures observed in the films are correlated with the film resistivities and some data are presented to establish the existence of the various types of oxides of rhenium. ThERE is some interest in the use of thin films of rhenium metal as resistive elements in monolithic, thin-film integrated circuits. Some work has been done using evaporated films and it has been found that such films, if protected from the atmosphere by an evaporated layer of silicon monoxide, show excellent electrical stability up to temperatures of 500"." Rhenium films unprotected from the atmosphere tend to age and the electrical resistivity of the films increases as a function of time. Rhenium films, of the order of <100A thick, prepared by electron-beam evaporation techniques are found to oxidize very readily when exposed to dry air at room temperature. It would seem, therefore, that this aging phenomenon could be attributed to the oxidation of the metal films. In this investigation, the oxidation and crystallization behavior of thin films of rhenium evaporated onto silicon monoxide substrates were studied as a function of the substrate temperatures used during the evaporation. The films were examined using electron-microscopy and electron-diffraction techniques. EXPERIMENTAL RESULTS Rhenium metal was evaporated onto suitable prepared substrates which were heated to various temperatures. The evaporations were performed in a vacuum of approximately 5 x 1CT5 torr. The evaporation was carried out at a rate of approximately 10A per omin. The final film thickness was approximately lOOA and the resistance ranged from 5000 to 10,000 ohms per square. The substrates used for supporting the metal films were made by evaporating 75A of silicon monoxide onto freshly cleaved mica. The silicon monoxide film was then floated off the mica by immersing the composite in water. The film could then be picked up on a clean nickel grid. Silicon monoxide substrates were chosen because of their similarity to quartz and glass substrates commonly used for making thin-film resistors. Fuschillo, Gimpl, and McMas-ter have also shown that silicon monoxide films have only minor structural changes at temperatures up to 800°C. This fact simplified the interpretation of any changes observed in the electron micrographs or electron-diffraction patterns obtained from the deposited rhenium films. After the evaporations were completed, the substrates were cooled to room temperature, except where noted differently, before the coated substrates were removed from the vacuum system. All aging of the deposited films was done in a desiccator. The evaporated films were examined in an electron microscope equipped with a hot stage that would permit continuous observations of the samples up to temperatures of 1000°C. RESULTS A series of electron micrographs of the rhenium films deposited on the silicon monoxide substrates are shown to Figs. 1 to 3. In all cases, the metal films are approximately 100A thick and the micrographs were taken 1 hr after the deposition was completed. here was no apparent structure in the films deposited on the substrates held at the higher temperatures. The

Jan 1, 1967

By D. F. Atkins, B. A. Rogers

The constitutional diagram presented herein is relatively simple. Complete mutual solid solubility exists for an interval below the solidus line, a continuous curve with a flat minimum near 22 pct Cb and 1740°C. Upon cooling, the solid solution breaks up, except at the columbium-rich side, from two causes: zirconium-rich alloys transform under the influence of the ß-a transformation in zirconium; alloys of intermediate composition decompose into two solid solutions below 1000°C. The combined effect is the formation of a eutectoid at a temperature of 610°C and a composition of 17.5 pct Cb. The eutectoid horizontal extends from 6.5 to 87.0 pct Cb. Some age hardening effects have been observed in the zirconium-rich alloys but the positions of the solvus lines remain uncertain. IN recent years, zirconium has been produced in much larger quantities than were available previously. Correspondingly, the incentive for studying its alloy systems has increased, as the number of recent publications on alloy systems testifies. However, only a partial diagram of the Zr-Cb system has been published and relatively few references have been made to alloys of the two metals. Hodge&apos; investigated the Zr-Cb system up to about 25 pct Cb. His data on melting points were not sufficiently numerous to distinguish with certainty between the alternatives of a narrow eutec-tic horizontal and a wide flat minimum in the solidus curve. Although Hodge considered his results on transformations in the solid state to be only tentative, he suggested that the eutectoid in the zirconium-rich alloys lay at about 625 °C and 10 pct Cb and estimated that the solubility of colum-bium in zirconium at 625 °C was near 6 pct. According to Simcoe and Mudge,2 less than 0.5 pct Cb is soluble in zirconium at 800°C. These authors observed an increased strength in both the 0.5 and I pct Cb alloys made with hafnium-containing zirconium. According to Keeler,3 the strength of zirconium is increased by addition of columbium to a content of at least 3 pct. Keeler&apos; also observed a maximum in hardness at about 10 atomic pct Cb and commented on the brittleness of alloys of this composition. Anderson, Hayes, Rober-son, and Kroll5 investigated the tensile properties of Zr-Cb alloys containing 5.1 and 12.9 pct Cb at room temperature and at 343°C. The 12.9 pct alloy had a high tensile strength at room temperature but also a low percentage of elongation. All alloys had high elongation at 343 °C. Littona measured strength and elongation values of annealed alloys containing up to 27.5 pct Cb and found low elongation values for all of the alloys of high columbium content. Some observations on the resistance of Zr-Cb alloys to corrosion in water at high temperature have been published by Lustman, De Paul, Glatter, and Thomas&apos; who found that additions of columbium up to 1 pct had only a minor effect on the corrosion resistance of zirconium. Preparation of the Alloys Raw Material: Zirconium of a relatively good grade was available for making the alloys. It was obtained as scrap pieces that had been left over from an operation that included production by the iodide process, melting under a protecting atmosphere, and fabrication to plates. The individual pieces had hardness values of 24 to 32 Ra and a typical analysis is shown in Table I. The columbium also was scrap trimmed from sheets. It was furnished by the Fansteel Metallurgical Corp. and had a high ductility but its analysis was known only approximately. The metal probably contained about 0.5 pct Ta, perhaps 0.25 pct C, and a few hundredths percent each of iron, silicon, and titanium. Melting: The alloys were melted in a tungsten-electrode copper-crucible arc furnace similar to units that have been described recently in the metallurgical journals.&apos;.&apos; The crucible of this furnace is provided with a cavity in which a getter charge can be melted before the melting of the alloy charges. Hardness measurements on the ingots indicate that the getter charge takes up a considerable fraction of the oxygen and nitrogen from the helium atmosphere of the furnace. The alloys used in the investigation are given with their intended compositions, hardness, and melting points in Table 11. Fabrication: All alloys of the Zr-Cb system appear to be amenable to fabrication. At least, all of the compositions listed in Table II could be reduced to wires in a rotary swaging machine. The starting material was either slabs cut from ingots and ground by hand to rough cylinders or narrow strips trimmed from sheets made by cold rolling slabs. However, not all of the alloys could be fabricated satisfactorily by the same method. From 0 to 4 pct Cb and from 20 to 30 pct Cb or more, the alloys could be swaged cold from ¼ in. cylinders to 0.80 mm wires with only one intermediate annealing, sometimes with none. From 40 to 90 pct Cb, the alloys were difficult to swage either hot or cold but could

Jan 1, 1956

By M. E. Wadsworth

The Michigan State College of Mines was established ten years ago last September as the fourth and last of the iustitutions of Michigan which are devoted to higher education. From the moment of its inception its single object has been to send out men who are qualified to take active part in the development of the mineral wealth of our State and nation, and any study which is essential to this end will not be found wanting in its courses of instruction. The institution has been singularly happy in its location. It is an axiom of modern education that any school which is to obtain the greatest return for the money and energy spent in

Jan 1, 1898

By Harold V. Pearce

The fire which occurred in the fall of 1906, at the works of the Boston & Colorado Smelting Co., Argo, Colo., destroyed entirely the gold- and silver-refinery of the plant, and in view of the development of modern practice in the refining of copper-mattes, etc., the management decided that it would be inadvisable to rebuild that part of the works for the continued use of the process which had been conducted therein for so many years as a metallurgical secret. This decision probably removes altogether from the sphere of practice the &apos;(Pearce" method for the separation of gold. At all events, it removes the busi-

Jan 1, 1909

By Richard Klimpel

In this paper various formulae are developed which can be used to estimate stream flow rates or weight ratios given information on the stream components. The type and level of experimental error present in the stream component analyses does have an important bearing on the numerical values (and reliability) of the weight ratios calculated by the various formulae. A simple but theoretically sound method is shown for selecting appropriate estimation formulae for any given engineering operation. The derived formulae are applied to sets of experimental classification data for illustration purposes.

Jan 1, 1980

By Duk-Won Park, Syd S. Peng

For an adequate design of the shortwall face support, it is necessary to understand fully the support- roof interaction. A series of studies has been carried out at a shortwall panel to develop the methods of monitoring support resistance and determining load density of the chocks. Various aspects of applications, for improvement of chock design and understanding of roof conditions, are discussed.

Jan 1, 1981

SINCE I told you in the preceding chapter how the potter&apos;s art is followed in practice, now in this following one I wish to tell you how mortar* and bricks are made, and how and to what purpose they were discovered, although I know you will answer that you know it, inasmuch as it is an art known not only to skillful men but also to the unskilled ones by whom it is practiced, and that bricks and mortar were made and always will be made for the purpose of building. This I admit, but probably everyone does not know it as you do, and you perhaps, do not know its beginnings, although I remember having told you of them. Wishing to repeat it better now I shall begin with long ago, so that both you and I may be better satisfied. Therefore I tell you that you should know that all the arts that men practice in the world have been learned by them either through the process of reasoning from the principles of natural phenomena, from the actions of animals, by chance, or when forced either by some necessity or

Jan 1, 1942

By David J. Mack, Chin Bea Kim

The decomposition of the Ni-Zn eutectoid at 56 wt pct Zn was studied by isothermal transformation. Its progress was followed by metallographic, hardness, and X-ray diffraction methods. Three transformation products were found: lamellar pearlite at high temperatures; an intermediate temperature structure; and martensite at the lower temperaCures. No transition structu,ves were found. THE decomposition of the Ni-Zn eutectoid at 56 wt pct Zn was stuadied as part of a long-range program of study on the eutectoid transformation in alloy systems which do not have one or more components which exhibit allotropy. Available information on the Ni-Zn eutectoid transformation is limited to that presented in connection with the determination of the phase dilagram. No systematic studies of the eutectoid were found in the literature, alkhough the microstructures of the Ni-Zn eutectoid were reported by Tamuru.3 X-ray diffraction data exist for the ß, ß1, y , and y1 phases.&apos; EXPERIMENTAL PROCEDURE The eutectoid alloy was prepared from "A" nickel shot and Bunker Hill super-purity zinc (99.998 pct).

Jan 1, 1962

By Robert N. McIndoo

A good tire program must begin at the top; management must have an awareness of the tremendous potential for cost saving that tires represent. At Reserve Mining Co., tires account for 33% of the cost of maintaining its 44 tractor-trailer side-dump haulers and 22% of its 32 rear-dump trucks. In comparison, engine overhauls account for only 6% of the maintenance dollar. Doubling the present engine life would save only 3%. The open-pit mine, located near Babbitt, Minn., moves about 46 million t/y with its off highway fleet. Mine roadways total in excess of 160 km (100 miles) and about 1200 tires are in active use at any given time.

Jan 3, 1978

Magnetic Measurements on Auriferous Veins in Brazil. BY MARK C MA¬LAMPHY (Contribution 72-Preprint; also Trans, vol 110 4900 words) One of the lesser known gold-bearing regions of Brazil is in the vicinity of Lavras, in the State of Rio Grande do Sul Recently the Companhia Estrada de Ferro e Minas Sao Jeronymo has been making a detailed survey of the area, and the author of this paper was requested to study the possibility of applying geophysical methods. The present paper gives a few details of the work and the results obtained The problem was difficult and the results not particularly brilliant, according to the author, but the data are believed to represent another advance in the application of the magnetic method of prospecting The instrument used was a Schmidt-Lloyd vertical magnetic field balance made by Askania Werke It did not prove of value for the discovery of auriferous veins of the type there found It is believed, however, that fair results may be expected when studying the continuation of veins that disappear under alluvial covering The data thus obtained should be of exceptional value in directing the excavational work of prospecting A short appendix to the paper gives the results of magnetic observations in the Sao Jeronymo coal mine

Jan 1, 1935

By Benjamin Smith Lyman

It is a time-honored saying in the anthracite region that " under the conglomerate there is no coal;" and the adage is generally reckoned a sure guide in coal-exploration. Yet there are many places where conglomerate, even coarse conglomerate, occurs above important coal beds, and, among others, above the great Mammoth bed. One of the most striking of such occurrences is on the Shippen and Wetherill tract, half a dozen miles west of Tamaqua; and it illustrates remarkably the disastrous effect of a too unquestioning blind confidence in the sweeping literal truth of a broad generalization. Here there is a conspicuous crag formed by a twenty-foot bed of egg-conglomerate, dipping 60 degrees southerly, and jutting out boldly at the western end of a hill, where it is cut through by the small stream of Little Creek. The hill runs eastward for half a mile, with occasional exposures of pebbly rock along the western half of the crest. Eastward from the exposures lies the old Kentucky Bank mine, abandoned thirty years ago, where the Mammoth bed was worked down to water-level through a space of a mile and a quarter westward from the Palmer tunnel to the very edge of the

Jan 1, 1893

By Henry S. Brown, Jean E. Tilden

Pyrite, pyrrhotite, chalcopyrite, and sphalerite from deposits distributed within the Piedmont and Blue Ridge provinces of North Carolina and adjacent areas were examined by atomic absorption spectrophotometry for cobalt, nickel, manganese, lead, tin, chromium, molybdenum, and gold. The ore samples were also examined petrographically. Cobalt and nickel, in general, enter pyrite and pyrrhotite rather than chalcopyrite and sphalerite. Manganese generally enters sphalerite rather than the other phases where an alternative is possible. The presence of tin in sulfide minerals was noted in a group of deposits east of the known occurrences of tin oxide (cassiterite) in the Kings Mountain belt, which may indicate the presence of a more extensive tin belt in the southeastern Piedmont than was previously recognized. Pyrrhotite from a group of four deposits in Jackson and Clay Counties, North Carolina, differs from pyrrhotite from other Ducktown-type deposits in having cobalt/ nickel ratios less than one, finer grain sizes, and colloform texture. These differences suggest that that this group of deposits has had a history different from that of the other Ducktown-type deposits studied. No significant conclusions could be made based on the distribution of lead, chromium, molybdenum, or gold.

Jan 1, 1975

By R. A. Wyman

KYANITE schists in the Sudbury area have been generally described by Haw,&apos; who has also given particuLar information on preliminary treatment of three large samples from Dryden township, Ontario.&apos; Kyanite, garnet, biotite, quartz, and feldspar comprise the main ingredients of this ore. Kyanite is the valuable mineral. About 5½ tons of —35 +200 mesh product, made by dry rod milling, screening, and separation on the Exolon magnetic separator, were available for treatment by flotation. Magnetic separation had effectively reduced garnet and biotite so that flotation feed consisted essentially of kyanite, quartz, and feldspar, the kyanite content averaging 32 pct and representing about 86 pct of the kyanite in the original ore. Earlier work on kyanite at the Mines Branch, Ottawa, s-c employed an acid circuit, but to avoid production difficulties in the use of acids and at the same time take advantage of the fact that industrial minerals respond somewhat to soap flotation, it was decided first to investigate the higher pH levels. Exploratory tests using —65 +200 mesh feed ended with production of 96.6 pct kyanite concentrate rep-

Jan 1, 1959