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By J. D. Prater, H. R. Spedden, E. E. Malouf

Application of research findings to the old art of leaching copper from copper-bearing mine waste has resulted in a significant contribution of copper to over-all copper production. For example, at the completion of the current expansion program at the Kennecott properties in the United States, copper produced from waste dump leaching will amount to about 25% of the total production, whereas formerly only 2% was derived from this source. This planned expansion of copper leaching focused attention on the problem of developing more efficient methods for the recovery of copper from greatly increased volumes of copper-bearing so1utions.l Detailed investigations made in laboratory pilot plant and plant tests for the recovery of copper from copper-bearing solutions have included electrowinning, solvent extraction, ion exchange and cementation with iron in launders, precipitation drums, activated launders, and precipitation cones. The results of these investigations have led to the development of a precipitation cone-type recovery system having advantages over older methods.

Jan 4, 1966

By H. A. Dierks

PENNSYLVANIA's anthracite region lies in the heart of the richest and most densely populated area of the U. S. Nearly 70 million people live within a radius of 500 miles, in which 130,000 manufacturing plants employ more than 8 million workers. The region comprises some 3000 sq miles and contains 484 sq miles of coal measures, which folding and erosion have divided into four separate and distinct fields, known as the Northern, Eastern Middle, Western Middle, and Southern.

Jan 10, 1957

By James E. York

The honor so fairly earned and so incompletely and tardily paid to Henry Cort, the inventor of the puddling-furnace and the rolling-mill, has been fully set forth by Mr. Charles H. Morgan,' and needs no further emphasis here. In view of the importance of the rolling-mill in the treat ment of iron and steel, the paucity of information concerning it is surprising. With the exception of a book, written about 35 years ago, by Peter Ritter von Tunner, an Honorary Member of this Institute, and of desultory articles on simple sections, which have appeared in technical journals, I know of no publication attempting to treat this subject, although volumes have been written on the scientific theory and technical manipulations involved in other branches of the iron- and steel-industry. This strange anomaly may be due to the fact that roll-turning cannot be called a scientific business. It does not ordinarily come within the range of an educated engineer; yet it cannot be performed by an ordinary mechanic. It demands some of the qualifications of an engineer, in designing, and those of a mechanic, in execution. The men who have followeci this trade have controlled the training of their successors. In many cases the technical knowledge required has

Jan 1, 1907

By M. F. Goudge

Production of many industrial minerals reached all-time records in 1965. In keeping with the high level of industrial activity throughout the nation, producers of many industrial minerals operated at capacity or near capacity, notably the producers of phosphate, potash and sulfur. In the case of sulfur, the demand exceeded production and orders were filled, in part, from stocks accumulated in previous years. Industrial minerals as a group continued to increase both in value and quantity at a faster percentage rate than metallic minerals and fuels, The U.S. Bureau of Mines estimated that the value of industrial minerals produced in 1963 was $4318 million vs. $2006 million for metals. Preliminary estimates for 1965 indicate that current value of production was again more than 2% times that of metals, thus making apparent their importance to the industrial life of the nation.

Jan 2, 1966

By Horace Williams

IN VIEW of the frequent occurrence of petroleum in other parts of the world, it seems odd that so large an area as is contained within the borders of Brazil should be without this product. This apparent deficiency may be due, however, to our ignorance of the regions in which-it, may exist. In some places, indications point to the probable existence of petroleum in ages gone by; and while the presence of petroleum pools may be problematic, in several regions conditions not unfavorable to their occurrence exist. Yet, Brazil has enormous oil resources in the rich oil-shales in different parts of the country. Many of these shales are very rich and only suitable processes for the extraction of the oil are lacking. At the present time, only a few small experimental plants are producing oil by distillation from these shales. These plants have been the subject of recent investigations by the Geological and Mineralogical Survey, a. pre-liminary report of which is in the hands of the printer. The only regions where studies have not been made are the upper Amazon, the Acre, the Rio Negro, and the Peruvian frontier, which really seems to be the most promising field for, explorations of any in the country. In the vast plateau region of the interior north of the 20th parallel of latitude, granites, gneiss, mica schists, and, very old metamorphosed sedimentaries predominate. Later, sedimentaries occupy a minor position and, where found in the interior, represent a thin veneering resting on the older rocks. At several places near the coast they have a greater development and contain considerable beds of oil-shale and may, in some cases, offer conditions favorable for the occurrence of oil. Such deposits are found in the Permian rocks of central-and southern Maranhão; in the Tertiary and Cretaceous beds along the coast of Alagôas Sergipe, Bahia, and perhaps farther south in Espirito Santo; and in the Parahyba embayment north of Cape Frio and in the interior Tertiary basin of eastern Sao Paulo.

Jan 9, 1920

By D. V. Fites

Criteria for deciding when rock should be ripped and what ripping equipment and techniques should be used in given situations are discussed in this article. The relation between ripper performance and seismic wave velocities in various types of rock is also discussed. The ripper is not a new tool. In fact, it dates back as far as the Roman Empire. The Roman's ripper-mounted on wheels and shaped something like a plow — was pulled by oxen and used to loosen the earth for the shovelers and basket carriers building the Appian Way. There are records of rippers being used in this country in railroad construction between 1860 and 1880. However, the ripper as we know it today did not appear until about 1930. Tractor-drawn models were in use in 1931 on the Hoover Dam project. At that time they weighed about 7500 lb and were pulled by tractors with about 75 flywheel hp and up to 30,000 Ib total weight. The chief shortcomings of trailed

Jan 1, 1969

Prof. J. W. Richards, South Bethlehem, Pa. (in reply to several questions):—The cut representing some of the round briquettes which were under test shows that, at the brcaking-stresses, they break into lumps, and do not disintegrate into powder. The process is simplicity itself. I have followed the different processes for sintering iron-ores and flue-dust, am interested in all of them and wish them all success; but this process appealed to me strongly by its simplicity. It is in line with a method which I once tried to work out myself, but which never came to anything, namely, the agglomeration of fine iron-ores by means of Portland cement. As small an amount as 5 or 6 per cent. of Portland cement will enable fine ore to agglomerate and set into a briquette, but when I came to estimate the cost, I found it was a little too high. The Schumacher process, curiously enough, does not work well on iron-ore, but flue-dust thus treated does harden and give a strong briquette. In my attempts to find a reason for this difference, it has occurred to me that possibly the particles of flue-dust had been coated over with some sublimed silica, which might be an agent in the setting. But I found by experiment that neither sublimed silica, nor ordinary silica, nor ordinary alumina, would briquette. Chemically pure iron oxide briquetted quite hard; but the application of pressure is a necessary part of the operation. If simply moistened with the solution and allowed to stand it does not set hard, but the more pressure applied to it the hardcr it sets. Evidently the flue-dust particles must be pressed very close together in order to get the small proportion of active material wet, so that the particles shall act at their points of contact; for it is evident that only at the points of contact does the cementing action take place. The reactions are facilitated by considerable pressure, bringing the acting particles close together, and may go on with

Jan 1, 1913

By Arthur Taggart

FOREWORD THE tests herein described are part of an extended series of experiments, performed by the authors together with J. F. McClelland and L. W. Bahney, on the reclamation of metallics from foundry and manufacturing-plant scrap. The most obstinate problem encountered was the proper cleaning of the metal. INTRODUCTION In the manufacture of brass and brass products the weight of the finished product leaving the plant is much less than the total weight of copper and zinc entering. A small part of this discrepancy is due to the unavoidable oxidation of the metals in melting, but by far the largest part of the loss is in the form of metallic particles of copper, zinc, and brass. These losses occur principally at three points in the process: (a) in the casting-shop ashes; (b) in the slags from furnaces melting scrap brass; (c) in material spilled on the floor throughout the manufacturing process. The amount of these products in some plants is nearly 100 tons per 24 hours. Casting-shop ashes contain the metal spilled from the crucibles during melting and pouring, and the metal included in the slags formed in the melting process. The ashes also contain pieces of broken crucibles with adhering metal; 20 to 30 per cent. of unburned coal is also present. The metal in casting-shop ashes contains clean pieces of zinc or copper ingots weighing 1 to 2 lb., jagged pieces of metal of all shapes ranging in size from several inches down to the finest dust, and shot and botryoidal shapes ranging in size from 2 or 3 in. down to 0.01 mm. or less in diameter. Slags from furnaces melting scrap brass contain metal in the form of small shot.

Jan 2, 1916

By Richard V. Ageton

Salt bodies in the form of rolls, horses (sometimes called horsebacks), folds, wants and pinches1 have been encountered while driving entries and mining out rooms during the development of the potash mines in New Mexico. Superficially these sporadic salt occurrences appear to be much alike, but closer examination reveals individual characteristics, and after four years of observation it seems possible to divide them into three general groups that may tentatively be called "depositional," "erosional," and "structural." The data collected are not yet sufficient to permit forecasts of their probable location, so that the annoyance of having to mine salt instead of potash could be avoided or lessened. However, the information so far available appears to throw some light on the occurrence of the sylvite2 bed now being mined, and it is as a progress report that the writer presents the results of his observations. The mines of the United States Potash Co. and the Potash Company of America are about 20 miles northeast of Carlsbad, in Eddy County, N. M. They are on the southwestern flank of the Permian salt basin, which underlies western Texas, Oklahoma and Kansas, south-central Nebraska, southeastern Colorado and eastern New Mexico. The cuttings from many oil wells and the cores from the potash tests drilled in this basin indicate that this salt series approached its greatest thickness (about 4000 ft.) in the southeastern part of New Mexico and the adjoining portions of Texas, and that the most advanced stages of

Jan 1, 1938

Joseph Esrey Johnson, Jr., had already achieved rare distinction as an able metallurgist, clear thinker, brilliant author, and wise consulting engineer to bankers and operators; he had achieved the essentials of a great career when death cut short his activities on Apr. 4, 1919, in the forty-ninth year of his age. He belonged to a family of iron blast-furnace men and mine managers. His father, Major J. E. Johnson, after serving with distinction in the Army of the North, identified himself with the iron mines and blast furnace at Longdale, Va., with which he was connected during almost his entire business life. It is significant that, during those troublous times of reconstruction in the South, he enjoyed always the affection and respect of his neighbors and associates alike. From him his son obtained not only a thorough training in blast-furnace practice and iron mining, but great personal courage and force of character. His mother, who survives both her husband and sons, possesses rare intellectuality, humor and a tenderness and human sympathy which those who were privileged to know well J. E. Johnson, Jr., recognized beneath his exterior of aggressiveness and will power. In a recently published analysis of the qualities which characterize the world's great men, three traits stand out preeminently; viz., independence, courage, and intellectuality. Each of these characteristics J. E. Johnson, Jr., possessed in extraordinary degree. His early education was obtained under a private tutor at Longdale, and this circumstance probably enhanced , a natural tendency to independence of character and individuality which, however, under the control of his

Jan 5, 1919

By C. R. McClure

The objective of this papef is to summarize briefly the practical use of rock mechanics in design and construction of various types of structures. These range from foundation for industrial facilities, nuclear power plants, bridges and dams to tunnels and underground caverns. The use of rock mechanics has varied from performing a few laboratory unconfined compressive tests on core samples to complete field and laboratory tests for underground power caverns. The primary difference between the rock mechanics studies we hare for construction projects and those most commonly found in the literature is that our tests must provide immediate answers to specific questions facing a design or construction engineer. For example, when we make a plate-bearing test we arrive at a load-deformation relationship. We realize that this is not a true modulus of elasticity. Yet, when considering the resistance the rock will provide against forces occurring in a pressure tunnel it is a far more useful value than the true modulus of elasticity of the rock. Another example of this difference in interest is in the use of flat jacks. Many people criticize the use of flat jacks because they measure the stresses in the disturbed zone very near the surface and do not represent the undisturbed stress condition in the rock. However, in actual construction it is frequently those near-surface stresses with which we must cope. We are interested in both the stress conditions present prior to excavation and those as modified by construction of an exploratory adit or drift. Fundamentally, we are interested in the practical application of rock mechanics in the solution of problems of design and construction of civil engineering works.

Jan 1, 1968

By Donald R. Williamson

Ore estimation at Cyprus Pima mine begins with estimating average copper grades for mine model blocks. Accuracy of the estimates has been checked four times in the last several years by comparing the estimates with arithmetic averages of corresponding blasthole (BH) assays. The data file now contains 3.567 estimated blockgrades and more than 10,000 blasthole assays. These data were compared by straight-line regression analysis at appropriate intervals as the body of data grew. Arithmetic averages of the estimates differed each time from arithmetic averages of the BH averages by nearly the same amount. More significantly, regression curves of the new total sets of data did not change position appreciably showing that copper grade estimates of blocks in all grade ranges from the lowest to the highest grade ores remained in error by nearly the same amount. Other studies revealed that core hole assays of the dominant ore type are biased and that that bias almost equals the error in estimation. Discovery of constancy in error indicated that regression analysis could be a means for correcting estimates of average block copper grades. A correction for estimated block grades was developed. It required determining which regression is appropriate for the particular problem, and a mechanism that is demonstrably sound. This paper describes the problem and the solution: No comparable study has been, found in the literature. Two other applications of regression analysis to metal grade comparisons are presented. Each adds a bit of support to a generalization which was suggested by correction of average block copper grades, namely, when performance of an estimate is to be evaluated, the variable taken to be the yardstick for the performance should be regressed on the estimate.

Jan 1, 1980

FRIENDS of the late Charles F. Rand presented in 1930 a sum of money from which. the income is available to support various phases of the work of the Institute in which Mr. Rand was so deeply interested. At present the fund amounts to $10,000. The specific terms of the deed of gift are as follows: "The fund collected to establish a memorial to the late Charles F. Rand shall be placed in the custody of the Board of Directors of the American Institute of Mining and Metallurgical Engineers, to be set up as a trust to be known as the `Charles F. Rand Foundation', the income of which shall each year be applied to a distinct purpose to be decided upon in that year by vote of the Board of Directors. This purpose shall be such as to promote the general welfare of the Institute and to constitute a permanent memorial of the usefulness of Mr. Rand, who for many years gave unstintingly of his time and talents in its service.

Jan 1, 1952

By A. Hamilton Garner

The occurrence of oil seepages in Venezuela has been known since the early days of Spanish occupation. It was not until 1912, however, that any serious exploration work was undertaken. In that year, the Caribbean Petroleum Co., then a subsidiary of the General Asphalt Co., employed a large staff of geologists to make a systematic survey of large areas in eastern and western Venezuela, selecting the most desirable localities out of the immense area covered by the Valladares concession. This preliminary work was completed in the fall of 1913, and in February, 1914, the company completed its first commercial well at Mene Grande. Development work has progressed slowly, for various reasons, but petroleum in quantity has been encountered in nine widely separated localities. The Mene Grande field has been put on a producing basis and approximately 4,000,000 bbl. of oil is being shipped annually. Increasing quantities of oil are now being drawn from El Mene and La Rosa. In the light of these developments, the world's need for oil reserves, and the proximity of Venezuela to the United States, American capital is being attracted more and more to Venezuela. Although considerable careful geological work has been done in Venezuela by the various oil companies now operating, most of the data is buried in the company files, and the published literature has been extremely meager. The most valuable contribution to date has been a map and report by Jahn, which, as it was printed in Spanish, is not generally available to the American oil public. Venezuela, located in the northwestern part of South America on the Caribbean Sea, lies between l° and 12° north latitude. Its principal

Jan 1, 1925

By K. Huessener

Discussion of the paper of K. HUESSENER, presented at the New York. meeting, February, .1916, and printed in Bulletin No. -110, February, 1916, pp. 443 to 474. KARL NIBECKER, Youngstown, O.-It has been contended that the method of measuring the operation of a blast-furnace boiler plant by means of the amount of steam generated per pound of coke used in the blast furnace is not of any value and even that it is quite misleading. It has been found, in the plant with which I am connected, that, in general, a blast furnace will operate during a month so close to average. conditions that the average monthly measure of the plant efficiency is indicated by the number of pounds of steam made per pound of coke put into the furnace, neglecting the amount of iron made and the amount of gas used for heating the stoves. For some time, it has been our custom to keep a record of this figure and use it as a general indicator of the operating practice. In comparing this figure from two different plants we have found some difficulty, due to differing conditions. It is conceivable but not altogether probable that a slight difference in burden, kind of ore or coke, would account for this difference. The method of using the gas, whether washed or unwashed, and the plant arrangement, may affect this number. For several plants on which we have worked up this number, we have found that most of the ordinary running irregularities are eliminated during a run of a month or more and that the number is, therefore, satisfactory. In connection with a plot of the number of pounds of steam generated per pound of coke, we are also plotting the production of the furnaces and the pounds of coke used per ton of production. With these three curves plotted on the same sheet, we believe that the operating man has sufficient information to judge of the efficiency of his plant' for any month.

Jan 5, 1916

By Marc W. Bodine

Insoluble residues from three sequences of Paleozoic marine evaporates (Retsof salt bed in western New York, Salado Formation in southeastern New Mexico, and Paradox Member of the Hermosa Formation in southeastern Utah) are rich in trioctahedral clays. Chlorite (clinochlore), corrensite (mixed-layer chlorite-trioctahedral smectite), talc, and illite (the only dioctahedral clay) are the dominant clay minerals; serpentine, discrete trioctahedral smectite (saponite), and interstratified talc-trioctahedral smectite are sporadically abundant. These clay-mineral assemblages differ chemically and mineralogically from those observed in most continental and normal marine rocks, which commonly contain kaolinite, dioctahedral smectite (beidellite-montmorillonite), illite, mixed-layer illite-dioctahedral smectite, and, in most cases, no more than minor quantities of trioctahedral clay minerals. The distinctive clay mineralogy in these evaporate sequences suggests a largely authigenic origin. These clay minerals are thought to have formed during deposition and early diagenesis through interaction between argillaceous detritus and Mg-rich marine evaporate brines.

Jan 1, 1985

By James P. Kimball

By the term weathering of coal is meant the process of deterioration to which under various circi~mstances it may be exposed at ordinary temperatures, both from outward agencies on the one hand, and on the other hand from its own constitutional qualities. This process involves along with some minor qualitative changes certain quantitative changes resulting in a gradual and limited reduction in the quantity of the organic elements, and relatively a corresponding increase of its inorganic or mineral constituents as represented by its ashes, and often in an increase of the absolute weight of the coal. In common with many mineral substances, coal absorbs oxygen

Jan 1, 1880

By E. Mcl. Tittmann

Deep-seated human instincts urge us to positively mark the passage of time. We celebrate the passage of each year. Years give way to decades, and decades to half centuries and centuries. At all these mileposts we are inclined to pause, take a look around and catch our breaths before embarking on the next leg. We are at such a point now and this meeting I am sure will give direction to the road ahead into the decade of the seventies. In looking around at this point, 1979, it is obvious to all of us that the environment in which we must mine, mill, smelt and refine lead and zinc has radically changed. These changes have, of course, occurred over a long period of time. They have, however, all been in the same general direction. They have all had the same motivation. The period of greatest contrast is probably the fifteen years just before World War II and the fifteen years following the end of that war. I thought that I might review briefly with you what seems to me to be four of the more important changes that have developed since World War II that profoundly affect our activities in the lead and zinc industry. I mentioned before that all these changes have been in the same direction; that is, they have all tended to restrict our freedom of action in pursuing our objective of producing lead and zinc on a competitive basis at a profit. Consequently, in discussing them you may think that I am merely viewing with alarm. This is not the intent. This is merely supposed to be an objective analysis. I think it appropriate before discussing these trends in detail to examine the position of lead and zinc today.

Jan 1, 1970

By Theodore H. Eyde

The Superior Oil Co. drilled two holes, 4720 and 5940 ft, respectively, using conventional oilfield rotary drilling equipment. The results indicated that large rotary drills can be adapted to mineral exploration purposes with few modifications. The principal advantages are: a large hole diameter, excellent samples of cuttings, a geolograph which is a constant drilling record, rapid penetration even in hard rocks, and the ability to use electric logs for measuring the properties of the rock being penetrated. The disadvantages are the high cost of mobilization, drilling, and oilfield service at remote locations. Though the oilfield sampling techniques are adequate for identifying lithology, improvements are necessary to obtain representative samples for analytical purposes. As deeper targets are explored, mineral exploration organizations will have to resort to rotary drilling.

Jan 1, 1975

By W. H. Adams

I DOUBT if many of our engineers know of the existence of coal-fields extending over hundreds of miles of territory bordering on and lying contiguous to the Rio Grande River in Mexico. Essential as these facts are to those contemplating the starting of industrial works along our frontier, I have not been able to learn that any surveys or examinations have been made of these deposits, and I trust the preliminary and unofficial investigations lately made by myself may be found of interest, especially to those of our members whose experience has been with poor fuel, or in districts remote from railway facilities. While it is true that Northern Mexico is generally bare of charcoal-making timber, yet no greater mistake can be made than to condemn the light, quick-growing woods found in profusion, and which cannot be excelled in flame or heat-producing qualities for boilers, reverberatory furnaces, or hearths. No country could be surer of a full supply of wood if wise legislation in regard to irrigation and preservation of young timber were adopted and enforced, but the beneficiation of the low-grade ores of Mexico demands a more dense fuel for furnace work, and, fortunately for metallurgists, who will hereafter make this frontier a base of operations, there have been disclosed, near the surface, seemingly inexhaustible beds of semi-anthracite and bituminous coals. No extensive openings have as yet been made, and my own workings at the Cedral mines are all that can yet be said to prove the quantity and quality of the coal, other openings furnishing only corroborative evidence. Our location (one hundred and ten miles west of the Rio Grande River) is on the western line of the depository basin, as it has existed since the period of activity along the volcanic line. The region farther inland I have not examined, but the elevations, as a rule, are much greater, though from the nature of the formation, they are not necessarily barren-ground. Beginning at the base of the Santa Rosa Mountains (location of the Cedral mines), we find very interesting breaks in the foot-hills, disclosing the stratified rocks from the volcanic centres to the valleys.

Jan 1, 1882