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THE TRANSACTIONS of the Institute for the early years display but Little interest in physical metallurgy-indeed, it is striking how thoroughly process metallurgy absorbed attention until quite recent years. The first volume carries no article that can be strictly described as physical metallurgy, unless one on the rolling and hammering of ingots be doubtfully so described. Nor does the second volume contribute more the interest then was in mining, and in production methods, both ferrous and nonferrous, with much attention to the new methods of making steel. The third volume records papers on: the condition of carbon in gray and white iron, a paper devoted to chemical rather than microscopic analysis; the annealing of spiegeleisen; phosphorus and carbon in iron and steel, similarly chemical. Much attention was given, and continued to be given for years, to the manufacture and behavior of rails. The question of the nature of steel appeared early (Vol. 11)-What is Steel, by A. L. Holley-where arguments on nomenclature were already active; and Holley also bemoans, in modern spirit, the Inadequate Union of Engineering Science and Art; Pearse wrote on cast iron for guns (reflecting again the ironic beneficence of war in metallurgy), and said that Captain Walbach was the first to insist on chemical analysis of gun irons; he quotes Major Wade's study of comparative hardness, using penetration hardness measurements (Brinell was to come later), and quotes the important Reports on the Strength and Other Properties of Metals for Cannon, by H. C. Baird, Philadelphia, 1855, in which the advanced state of tensile testing at the time is shown. Hewitt, in Vol V, comments upon the function played by technical schools and technical societies upon the growth of metal-

Jan 1, 1948

By J. R. Barrett

Geotechnical techniques to evaluate conditions in underground metalliferous mines change through a mine's development from prefeasibility to remnant mining. The objectives of this paper are to determine the geotechnical requirements of typical underground metalliferous mining projects, to determine any shortfalls in conventional geotechnical techniques in satisfying these requirements, and to determine the costs of such investigations in proportion to the project expenditure. Finally, areas for future research and development are discussed. A group of over one hundred case history studies are examined to generate data on typical mining problems. The case studies include projects at most Australian underground metalliferous mining operations supplemented with case studies in Canada, Africa, Asia and Europe.

Jan 1, 1983

By Ralph H. Kress

Haulage trucks designed expressly for mine service were introduced about 35 years ago. The first models to arrive on the scene hauled about 15 tons and easily outperformed the modified highway trucks that had been used for mine haulage up to that time. The specialized trucks obviously had a greater potential for mining operations, and once this fact was recognized, competitive pressures in both the mining and truck-manufacturing industries drove the new vehicles toward ever more efficient performance. Many changes in truck design resulted, but not all were accepted for a variety of reasons. Often poor design was the reason, but in many cases progressive and promising designs were abandoned only because the truck manufacturer lacked the courage, tenacity, or vision to capitalize on them. There were also many cases where a promising new design was abandoned because the prototypes were initiated in a mine where personnel lacked the patience to prove them. Truck Startup Takes A Team Ally new truck that is to succeed and contribute to lower mine haulage costs must be well conceived and launched with good teamwork on the part of all concerned. Naturally, it is essential to have a good overall truck design at the outset to make this teamwork worthwhile. The design must include the selection of the right components manufactured by suppliers that can each do justice to their particular part of the new truck. Last, but by no means least, the mine operator where the truck is to be launched must be enthusiastic in his efforts to see the new vehicle through to successful operation.

Jan 1, 1971

By Michael K. O’Leary, William D. Coplin

Risks from political instability and government policies restricting equity ownership, local operations and transfers of payments affect the profitability of foreign mining ventures. More than seat-of-the-pants judgments and old-boy networks are required to anticipate these risks and to take actions appropriate to offsetting them. A system for making political forecasts, called the Prince System, and a series of charts relaying risks to a production of key minerals has been developed.

Jan 1, 1985

By Hugh Archbald

IT is possible to construct a simple diagram of the earnings, or the production, of the men employed at a coal mine that will show not only if the conditions tend toward contentment among the men, but if the operating distribution of the work is correct. As earnings are the greatest cause of discontent, even exceeding all the other causes, if contentment exists in the matter of earnings, the likelihood of other discontents flaring up is greatly lessened. The basis of such a diagram would be the Gaussian curve of the normal variation in human ability. Such a curve has long been recog-nized. H. L. Moore,1 in discussing the quantitative relation between wages and ability says: "It has been pointed out that industrial efficiency is dependent upon physical, mental, and moral qualities, and these qualities . . . there is good reason for regarding as being distributed according to the Gaussian law..

Jan 7, 1924

By Roy L. Zuber

Identification and analysis of mining hazards involves the correlation of accident, injury and illness information from all segments of the mining industry. It would not be feasible to process the volume of data involved without substantial reliance upon a computerized information system similar to that maintained by the Health and Safety Analysis Center. Numerous statistical programs are applied to the computerized accident-injury-illness data base to identify those mining tasks and associated activities which are responsible for most of the injuries and occupational illnesses. These programs are used to flag those mining tasks or conditions at specific mines or segments of the mining industry where either a significant increase in the injury/illness trend has been reported or where the number of injuries/illnesses related to specific mining tasks or conditions are high. Upon identification of those mining hazards which warrant further analysis, a computerized search of the coded accident data is performed to correlate the predominant categories by cause of injury or illness, source of injury, nature of injury, type of accident, etc. From this correlation, those factors most common to the conditions responsible for the hazard may be identified. Based upon analyses of this form, recommendations are made regarding the appropriate engineering, training, and/or operational improvements necessary to alleviate the hazard. In addition to mining hazard analysis, the computerized data base also has application in the area of optimum resource allocation. Computer programs have been developed to assist management in allocating resources based upon organizational requirements and historical accident - injury trends.

Jan 1, 1983

By C. B. Thwing

IT is likely that among most races, owing to the ease of finding and working clay, the making of clay utensils was learned earlier than the molding of metal implements. The ancients made good pottery and durable brick in kilns that wasted fully one-half the heat and spoiled fully one-fourth of the ware; and, taking the clayworking industry as a whole, we are doing the same today. The chemical and physical changes involved in the burning of clay are so many and vary so much with the composition of the clay that it is not surprising that the rule-of-thumb methods so commonly employed fail to give uniform results. In its passage from plastic clay to the vitreous or stonelike character the mingled minerals and accidental organic impurities of which the clay is blended must pass through four stages, the second and third usually overlapping, and the fourth often beginning before the third is complete. These stages in their order with the rising temperature are drying, dehydration, oxidation, vitrification. In the first part of the drying stage, usually accomplished in part outside the kiln, the water mixed with clay is dried out at temperatures not much exceeding the boiling point of water. In the later part of this stage, within the kiln, the hygroscopic water, absorbed from the air is expelled at somewhat higher temperatures, this stage being known as watersmoking. Some clays are very sensitive to temperature during the drying stage and if the temperature exceeds 100°, the ware becomes checked. Other clays may be dried more rapidly without danger. In down-draft kilns, the draft is slight during the watersmoking stage and the water driven off from the top rows condenses on the ware in the bottom of the kiln, with the result that high temperatures are likely to be reached at the top of the kiln before the bottom is fully dry. The lag in temperature of the bottom persists to the second stage in spite of the better draft then prevailing.

Jan 9, 1919

By Marie L. V. Gayler

WITHOUT diffusion taking place in liquid metals and alloys, no castings could be made; it is therefore the most important factor affecting the structure of metals. Diffusion involves the interchange of atoms, a process which takes place during the life history of an ingot. In the liquid, atoms are in a state of high thermal agitation, but this thermal vibration is reduced in amplitude with falling temperature. When solidification sets in, the atoms arrange themselves on an ordered space lattice and the changes in structure which take place in the solid are due to the interchange of atoms on this space lattice. The rate of atomic interchange-e.g., of diffusion-is most rapid at temperatures close to the melting point and decelerates as the temperature is lowered. At room temperature, the rate of diffusion is practically negligible in most alloys, and any change in structure can only be brought about by using methods which will accelerate the rate of diffusion. The rate of diffusion depends on three factors (I) temperature; (2) concentration gradient and (3) activation energy. The growth of grains and particles in the solid alloy also depend on these factors and are therefore intimately associated with diffusion. The rate of homogenization in a cast alloy depends on several factors, such as: (I) rate of solidification, which involves grain and particle size which, in their turn, depend on diffusion: (2) the nature of the constituents; (3) the temperature interval between the melting point of the metal or alloy and the temperature at which it is being heat-treated. It is well known that coarse, cast structures are extremely difficult-if possible to homogenize, and the finer the grain size and particle size, the more readily solid solution will take place. The rate of diffusion depends, also, largely on the nature of the constituents; for instance, copper and magnesium form solid solutions with aluminum quite readily but nickel and iron do not; neither do certain intermetallic compounds, such as alpha and beta FeSi. Furthermore, the actual formation of intermetallic compounds may be a very slow process, particularly when they are formed in the solid state as equilibrium products. For example, ßFeSi is formed in the solid as the result of the reaction aFeSi + Al?ß FeSi. The particles of aFeSi become sur¬rounded with a reaction ring of ßßFeSi. This layer is formed as the result of diffusion of atoms taking place between the aluminum matrix and aFeSi. As the amount of ßFeSi surrounding the core of aFeSi increases the concentration gradient becomes low and so the rate of diffusion of atoms also decreases until it practically ceases. This occurs after a comparatively thin layer of ßFeSi has been formed. It follows that when intermetallic compounds of this type are formed in the solid, as the result of diffusion, it is generally impossible ever to attain equilibrium, since the forma-

Jan 1, 1944

By Sharon Brady, Catherine O’Donoghue, John V. Beall, Paul C. Merritt

Between 1950 and 1965, more than 80% of all phosphate rock produced in the world each year was used as fertilizer, either directly applied to the soil or processed into mixed chemical fertilizers. Of the potassium salts produced, 95% followed suit. A variety of uses in industrial chemicals and consumer products absorbed the remaining percentage of each. Future trends in these two commodities will be dominated by what happens to the fertilizer market. Farming is much the same as mining the soil. Plants remove the minerals little by little. Phosphate and potash comprise two of the three primary nutrients removed in this way, the third being nitrogen. Phosphate stimulates early root formation and growth, whereas potash is a salt necessary to root strength.

Jan 10, 1966

By George B. Clark

THE geological data emphasized so successfully in prospecting for new deposits, that is, structural controls, strength of solutions, and type of mineralization, are basically those required for successful exploitation. In the mining of newly discovered deposits the most economical methods should be employed as early as possible to keep the overall cost per unit produced at a minimum and to permit maximum extraction of valuable minerals. A crucial question is: How can geological data be translated into useful quantitative results which will aid in achieving this end? H. E. McKinistry1 has suggested that a solution may be reached in one of two ways: 1-the usual approach, use of judgment based on experience; or 2-mathematical calculations and tests on models, both subject to certain limitations. He also suggests that in addition to better use of geology more case data and theoretical data are needed on which to base sound judgment. Further research, therefore, is necessary. Perhaps in this field the emphasis should be on more specialization in mining methods and ground movement by men with thorough training in physics, engineering, geology, and underground mining. These specialists would be equipped to point out the most economical and scientific methods of exploitation.

Jan 8, 1954

By Alan B. Nicol, W. T. Parry

The outcome of these tests has been twofold. They have served to demonstrate that the tiltmeter is a useful and dependable instrument which could prove to be of significant value in reaching the goals of landslide prediction and control, and they have raised a good many more questions about the mechanism of slides than they have answered. It seems likely that many of the old concepts and assumptions will be modified or discarded as more knowledge of actual field phenomenon is gained. Safety and economy are paramount concerns in determining slope stability. These two considerations govern the feasibility and character of slope construction from start to finish.

Jan 1, 1970

By H. R. Hanley

ONE of the most important contributions to the art of electrolytic zinc production-has been the aluminum cathode. This has been used in all major production: since its commercial development in 1916. The literature is replete with important contributions, some of which may have been replaced by better ones, but thus far there appears no other metal to take the place of aluminum as cathode material. Credit for this innovation goes to Sherard Cowper Coles, of England. When experi-menting on the extraction of-zinc from Broken Hill ore at Hayle, Cornwall, in 1893, he introduced the aluminum cathode, and in 1895 obtained British Patent-No. 20073. The reason for this dominant position of aluminum as cathode mate-rial in zinc sulphate electrolytes is its unique surface, to which electro-deposited metals usually do not tightly adhere. The metal must be of high purity for best results. It is possible to develop a starting-sheet method by which thin electro-deposited sheets of cathode zinc are made and stripped from a smooth aluminum plate. Such thin sheets of cathode zinc may be used as arc tine copper sheets in standard electrolytic copper-refinery practice. However, complications arise because of extreme warping of the zinc starting sheet after a .few hours of deposition, and thus special arrangements must be made to compensate for this abnormality.

Jan 1, 1938

By Kevin M. O’Connor

Examples are presented in which Time Domain Reflectometry (TDR) was employed to locate deformation in rock masses induced by mining. The first example involved monitoring the propogation of overburden fractures above a longwall coal panel and the second example involved the use of TDR to monitor rock mass deformation in the vicinity of a strip mine highwall. Rock mass deformation, strata separation and large block movement generated strains and failure along coaxial cables which were installed in drill holes and the TDR reflections generated by these strains and failures were monitored. Analysis of field data and a preliminary laboratory test indicate that it may be possible not only to locate rock mass movements but also to quantify these movements with TDR data.

Jan 1, 1984

By Ernest F. Burchard

MOST of the iron ore smelted in Alabama blast furnaces is mined within Alabama, although deposits in the neighboring States of Georgia and Tennessee may be drawn upon when occasion requires. Of the four commercial kinds of iron ore, the anhydrous ferric oxide, hematite (Fe2O3) ; the hydrous ferric oxide, mostly the type commonly known as limonite (2 Fe2O33H2O) ; the carbonate, siderite (FeCO3) ; and the magnetic oxide, magnetite (Fe:3O4) ; the first two are found in abundance in Alabama, the third in less than commercial quantities, and the fourth only rarely. Both the hematite and the hydroxide are found in somewhat different forms according to their geologic environment. The Red Mountain hematite, of Silurian age, that crops out in well¬defined beds for 1.50 miles northeast-southwest and 40 miles northwest-southeast is the predominant source of ore. Only a small part of this area carries ore of commercial value; Birmingham and Gadsden are now the only centers of production. The ore is of sedimentary origin, probably altered from vast deposits of greensand mixed with calcareous, fossiliferous. marine debris. Other types of hematite not vet mined commercially are in metamorphosed rocks-red ore in slates in Columbiana Mountain and specular hematite (gray ore) in quartzite in the Talladega Hills.

Jan 1, 1938

By Swapan Bhattacharya

United States federal and state regulatory authorities require underground mine operators to adopt adequate measures to minimize material damage to the surface caused by mine subsidence. This paper presents an approach to define and determine the extent of material damage due to subsidence from underground coal mining. The basic steps involved in the development of adequate criteria have been enumerated together with the approaches and methodologies used.

Jan 1, 1984

By E. C. Wilson

The knowledge concerning the lubrication of open gearing for mining machinery has contained many unknowns and at its best has relied to a great degree on a "Rule of Thumb" procedure. It will be within the scope of this paper to explain what we have learned to date and what must be learned in the future. Action of Two Gears in Mesh Let us review some of the basic fundamentals concerning the action of two gears during mesh. Most of the gears we use are involute and may be spur, helical, or herringbone. The gear contact is a combination of rolling and sliding action.

Jan 12, 1968

By S. P. Brown, J. E. Worthington

Increasingly, exploration geology seems to be growing into a practice overly separated from production geology, yet the eventual purpose of exploration is a producing mine. To help in the search for new deposits, exploration "lessons" will be drawn from the papers given at the Fall AIME Applied Geology Symposium. In addition, examples will be re-emphasized to show how early observation of matters now routine to mine work (for example, hydrology, rock mechanics, oxidation state) can help increase the effectiveness of exploration.

Jan 1, 1984

By A. M. Ross

DEURING the past year the uranium milling industry has seen the installation and initial operation of solvent extraction circuits in the Climax Uranium Co. mill at Grand Junction, Colo.; the Kerr-McGee Oil Industries mill at Shiprock, N. M.; and the AEC pilot plant at Grand Junction, operated by National Lead Co. Inc. The Vitro Uranium Co. mill in Salt Lake City is converting to solvent extraction, and the new Union Carbide Nuclear Co. mill to be constructed at Rifle, Colo., will also employ this method. Solvent extraction circuits will be incorporated in two mills now under construction -the Texas Zinc Minerals Co. mill at Mexican Hat, Utah, and the Gunnison Mining Co. mill at Gunnison, Colo. In Canada the expansion of the Eldorado mill at Port Radium includes installation of a solvent extraction circuit. Solvent Extraction Process: In simplest terms, the organic solvent is mixed with leach liquor and then the organic and aqueous phases are allowed to separate. By this contact the solvent selectively extracts uranium from the liquor, leaving a raffinate, or barren leach liquor, which may be discarded. The pregnant solvent is stripped of its uranium by con- tact with a stripping solution, such as aqueous sodium carbonate, which has a greater affinity for uranium than the solvent does. The barren solvent from the stripping step is available for further leach liquor extraction, and the pregnant stripping solution, which usually contains 30 to 60 g U3O8 per liter, is ready for precipitation of a final product, or uranium concentrate.

Jan 9, 1957

By T. C. Atchison, W. I. Duvall, D. E. Fogelson

Dr. Clark has given an excellent resum6 of the recent theoretical re- search work that has been done on the generation and propagation of stress waves in various types of media.1 Unfortunately the dynamic properties of rock do not fit the assumed properties of the idealized media. As a result, none of the theoretical solutions for the generation of stress waves by applied pressures to interior boundaries of the spherical or cylindrical cavity appear to be completely satisfactory to explain experimental data. This fact does not mean that the theoretical work is in error. It simply means that the appropriate dynamic properties of rock have not been taken into account in the present theoretical derivations. Because of the difficulty of theoretically accounting for the crushing and cracking that takes place when explosives are detonated in spherical or cylindrical cavities, it seems advisable that future theoretical studies should attempt to separate the generation of stress waves from the propagation of stress waves. Perhaps if these two problems are separated, we may be able to solve one of them satisfactorily so that theory and experimental data agree. Dr. Clark's resumé of the research work on scaling and crater formation by point charges is aimed at obtaining a basic understanding of the physical theory of rock breakage, wave generation, and wave propagation. A cursory reading of Dr. Clark's paper shows that there is very little information summarized that can be used by the practicing engineer in the field of blasting. When problems become too difficult to solve theoretically it is always helpful to take the empirical approach and collect experi-

Jan 1, 1967

By Paul B. Barton

Unconventional mineral deposits are those that differ significantly from productive deposits in mineralogy, grade, or geologic setting. Thus, the initial representatives of each deposit type are, by definition, “unconventional” until they are exploited. The “unconventional” status changes to "conventional" because of economic shifts (e.g., bulk silver ores), because of technological innovations (e.g., froth flotation), or simply through the recognition of, and production from, novel mineral concentrations. Heretofore the discovery of new deposit types has been almost entirely accidental, but the long- established concept of the geochemical cycle provides a nearly untouched opportunity and challenge for the application of geochemistry in predicting novel, potentially economic, mineral concentrations.

Jan 1, 1983