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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

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 Parke A. Dickey

POTENTIAL differences between strata of shale and sandstone have been recognized for about 15 years, and they form the basis of the electrical logging of oil wells. Hitherto these potentials have been ascribed solely to electrochemical reactions caused by the disturbing effects of the water in the drill hole through which they are generally measured. Observations by the author in wells empty of water and in a mine shaft suggest that potential differences between sandstones and shales are natural and specific properties of the rocks, although they are modified to measurement by the disturbing effects of the water in the drill hole. The cause of these potentials probably is to be sought in the relative polar adsorptive capacities of quartz and clay particles.

Jan 1, 1944

By L. K. Eigenbrod, F. Notaro

Enactment of Public Law 91-173 (Federal Coal Mine Health and Safety Act of 1969) has placed new responsibilities on the mining industry. The new law, aimed at eventually solving the problem of pneumoconiosis, sets new respirable dust standards at 2 mg per cu m. Techniques employed to date have been shown to lack total effectiveness in meeting the prescribed standards. Since it is possible that even the new standards will eventually have to be lowered to effectively attack the medical problem, the need for new and more reliable methods of assuring clean respirable air will intensity. This paper presents, in a preliminary manner, both the present technical capability and growth potential of cryogenic technology for supplying miners with clean breathing air. Work with two sizes of prototype supplied-air (cryogenic-liquid) respiratiors in Union Carbide's Fawn Coal mine, will be described. Other potentially fabricable systems will be discussed and a preliminary assessment made of the potential cost of introducing cryogenic air breathing systems in coal mine service.

Jan 1, 1972

By H. K. Shearer

Oil production in north Louisianat in 1939 was 25,249,640 bbl., a decrease of 11.2 per cent from 1938. The only important increases in production were in the Cotton Valley and Shreveport fields, but Caddo, Homer, Sligo and Zwolle also made slight gains. Greatest decreases were in the Lisbon and Rodessa fields. Xatural gas production of 313,333 million cu. ft. was an increase of 5.6 per cent over 1938. The increase was accounted for in the Monroe field, while all other fields showed only minor variations from the production of the previous year. Well completions in 1939, as compared with 1938, were as follows: The decline in number of completions was due entirely to lack of proved areas for drilling, and would have been greater except for a revival of interest in the old Caddo shallow field. A majority of the wells completed during the year were in various old, shallow fields, so the average depth of drilling was much less than in several preceding years, notwithstanding a few very deep tests. No new fields were discovered, the only wildcat well reported as a producer being a very small oil well in northwestern De Soto Parish, which is of no apparent commercial importance. Deep gas-distillate production in the Cotton Valley formation was opened at Lake Bistineau and Lisbon, and oil at Shongaloo, but all these wells were too small to encourage additional drilling. Extensions and Developments Caddo Field.—More active drilling was donc in the 36-year old Caddo field in 1939 than in any of the newer fields, with completion of 133 oil

Jan 1, 1940

By Henry Carlisle

W. W. Mein: One of the most amusing things in Nevada City – I was born and was going to school there - was that my mother made overcoats for us, and because they were different from other boys’ overcoats, we’d hide them under a bridge and pick them up on the way home. I left Nevada City with my parents when I was about eleven years old, and moved to Oakland. This was caused by the closing down of the hydraulic mines and my father being send to the El Cayo mine in Venezuela, which was then one of the richest gold mines in the world. Hamilton Smith operated the hydraulic mines in California, and when they were closed down by the Sawyer decision, he was persuaded by the Rothschilds to go to London. There, together, they formed the London Exploration Co.

Jan 1, 1964

Cobriza can only be described as the Machu Picchu of the mining business. This relatively new mine of the Cerro de Pasco Corp. in Peru, subsidiary of The Cerro Corp., was put on stream in December 1967. The best way to get there is to go in the company's HelioCourier with pilot Paco Perez. The plane is mostly engine and the pilot is without nerves. The trip starts at an elevation of 12,000 ft at La Oroya and ends at the Cobriza air strip near the top of the Continental Divide at 14,200 ft. Perez says this is the highest air strip in the world. The flight is made at an altibude below many of the peaks and it is easy to pick out the Inca Trail which follows the ridge line of the top of the Andes. Inca ruins are also visible from the aircraft. The drainage pattern, with a surprising number of lakes and rivers, can be seen and so, too, can a great deal of structural geology and numerous agricultural settlements dotting the altiplano. Cobriza is in the monta[n]a on the east side of the Andes, which is characterized by tropical climate and vegetation, an abrupt change from the frosty mountain atmosphere. The mountainsides are precipitous and the bottoms of the steep valleys are channels for roaring rivers. Such is the setting of Cobriza, above the swift cataracts of the Mantaro, benched out precariously at about 8700 ft elevation. The mountains rise in majestic splendor and the sun comes up late and sets at 3: 30 on winter afternoons. One of the lowest of the Cerro de Pasco camps, it is the most remote.

Jan 11, 1969

By S. M. Matthews, D. J. Maconochie, L. G. Alexander, V. H. Tillmann

Case studies of the behaviour of large open stopes at the New Broken Hill Consolidated Mine, Broken Hill and the CSA Mine, Cobar, N.S.W. are considered. Deformations were measured by multipoint rod extensometers in sufficient detail to note the phases of rock behaviour, from intact through to rock-fall. In one case readings were obtained from a zone of stress failure in which two bumps, felt as ground tremors, occurred. In this case noise and stress were also monitored. Deformations were analysed in relation to previously measured in situ rock stress, and conclusions drawn about the degree of conformity to, and the areas of departure from, elastic model behaviour. Attempts to describe the growth of instability utilize reduction factors of the apparent modulus, a magnification factor for the apparent Poisson's ratio, and a correlation between progressive noise count and displacement. Monitoring itself is seen as an aid in determiing the final dimensions of stopes and pillars. One large stope, of intermediate dimension 80 m, was mined essentially without change of plan, whereas a change in mining plan was necessary in other stopes. Aspects of interest to mine planners, and areas where futher research is needed, are indicated.

Jan 1, 1981

By Charles W. DeWitt

The ore treated at the reduction plant (called Yangdei) of the Chiksan Mining Co., Korea, is brought from four of the company mines, and from the small tribute mines. The largest shipments come from Sajunkohl mine, situated about a mile and a half from the mill (Fig. 1). The ore is quartz of medium hardness. The average assay value in gold is $6.95 per ton. At the mine the ore is put into bins, and is then trammed over an 8 per cent, grade to the tipple bins above the mill, where the ore is drawn through the mill holes as desired. The capacity of the tipple bins is about 3,500 tons. Ore from Moonsukohl, Chung Tarrie, Yang Chun, and the tribute mines is brought in by bulls and bull wagons. The bulls carry from 350 to 800 lb.; the average wagon load is about 1,200 1b. (Fig. 2). One shovelful of ore out of every ten is taken as a sample. Considerable ore is brought in from the outside mines, and this method of sampling is

Jan 1, 1916

By Tribhawan N. Srivastava

The Henderson Mine started production in 1976 utilizing a unique, push-pull, mine ventilation plan. As the mine expands in size, the mine ventilation requirements will increase and a more comprehensive system for maintaining ventilation will be needed. A computer simulation study was completed and has resulted in a revised, systematic, mine ventilation plan which is being implemented as mine development proceeds. Based on the computer simulation study, the new ventilation plan takes into account mining of the orebody simultaneously from both the 8100 and 7700 production levels. Present experience and empirical data indicate that volumes of air needed to adequately ventilate both production levels cannot be obtained utilizing the existing mine layout. The total volume of air needed for the mine excluding haulage tunnel will increase from 708 m3/s (1 500 000 cfm) to 1652 m3/s (3 500 000 cfm), thus a new No. 5 exhaust shaft and connecting drifts are being developed to expand the mine ventilation system to service both production levels. The original ventilation plan for the 7500 haulage level was to bring air from the No. 2 and No. 3 intake shafts and exhaust it through the 94X raise to the 8035 exhaust level and then through the No. 1 exhaust shaft to surface. Control of air volumes in loading drifts was initially planned to be achieved by air doors and air curtains. Air doors on the 7500 level require large cutouts, expensive installations and constant maintenance. The computer simulation study indicates that air- flow in the 7500-level production drifts can be con- trolled exclusively by air curtains which are less expensive to install and more effective in regulating airflows than air doors. Air from the 7500 level can be exhausted through a new raise to the new 7635 exhaust level and then through the new No. 5 exhaust shaft.

Jan 1, 1982

No review of underground mining should begin with anything but the new world safety record set at the Grace underground iron mine of Bethlehem Steel at Morgantown, Pa., on Friday, November 12. There had not been a disabling injury (an injury which keeps an employee away from his next scheduled shift) for 550 working days. In all, 2,660,080 man-hours had been worked by nearly 950 employees without a disabling injury. The record was wrested from Johns-Manville's Jeffrey mine at Asbestos, Que. At 3 p.m. Friday, December 3, miner Stanton E. Friend was completely buried under several feet of coarse rock, fortunately sustaining only cuts and multiple abrasions. But with his fall, the accident- free period came to an end at 2,778,600 man-hrs worked without a disabling injury-the new record!

Jan 2, 1966

By Sherwin F. Kelly

Drilling in the Oligocene potash basin of Alsace prior to 1927 had shown important differences of level in the salt beds thus encountered. TO explain this a somewhat unsatisfactory hypothesis of faulting had been advanced. During the latter part of 1926 and the beginning of 1927 our firm was engaged by two organizations1 for the purpose of trying to supplement, by an electrical survey, the geological data this far collected. As a result of this exploration it was possible to affirm that salt dome structures were present in the Oligocene basin of the Upper Rhine, something heretofore absolutely unknown in that region. Two salt domes were actually outlined: one, near Meyenheim, was made the subject of a communication to the Academy of Sciences, by G. Friedel;2 the other, near Hetten-schlag, was briefly discussed by C. and M. Schlumberger3 before the same academy. The purpose of this paper is to indicate the stratigraphic and structural conditions of the area where these salt domes were found; to discuss the results of the electrical survey which led to the location of the domes; and to indicate the new geological outlookwhich such a discovery suggests. Stratigraphy In the southern part of the Rhine graben the Oligocene rests almost directly on the Middle Jurassic and consists, in ascending order, of: 1. Green marls, not salt-bearing, composed of fresh and brackish water deposits. 2. Middle stage, salt-bearing, consisting of lower-schistose marls and upper, variegated marls. 3. Blue marls, not salt-bearing, but including gypsum deposits; hence sediments laid down in a bay more or less connected with the sea.

Jan 1, 1929

By D. W. Fuerstenau, S. Raghavan

This paper presents a brief summary of some of the thermo- dynamic aspects of flotation processes. Thermodynamic considerations that control interfacial and wetting behavior in mineral/water/air systems are discussed. Particular attention is given to the thermodynamics of collector adsorption.

Jan 1, 1976

By Douglas Bunting

With the gradual exhaustion of the upper veins in the anthracite coal-fields, the problem of mining at greater depths acquires increasing importance and demands the consideration .of a number of important factors, one of which is the greater earth-pressure and the consequent necessity of stronger support for the roof. Under the pillar-and-chamber system, almost exclusively followed in the Northen anthracite-field, the highest economy in mining is generally secured by leaving, on first mining, pillars only sufficient to support safely the overlying strata. As to the necessary size of such pillars, the opinions of mining experts are widely divergent. In establishing the width of chambers and pillars, the thickness of vein and its depth below the surface have received little consideration. For instance, it has been quite usual to work both overlying and underlying veins with the same width of chambers and pillars, when the lower vein was two and one-half times as thick, and twice as far below the surface, as the upper. In view of the generally-accepted theory that the crushing-strength of coal-pillars of the same base-area becomes less with increased height, it is probable, in this instance at least, that the moat economical mining has not been secured. This question of adequate pillar-support is economically less important down to about 800 ft. than at greater depths; and it is with reference to mining at these greater depths that the study of the subject here presented has been prompted. The necessity of leaving larger pillars, involving greater mining-costs per ton and also smaller yields per acre, is one of the troubles of deep working. To mine without leaving adequate pillar-supports will result, sooner or later, in a squeeze. Limited areas, it is true, have been mined at certain widths of

Jan 1, 1912

AMONG the features that make Inspiration of outstanding A interest, particularly to the engineer, is the fact that at various times it has used, as a major method of production, three more or less distinct methods of mining and three distinct methods of treating its ores. The following chronology is of interest : Major Mining Methods: 1915-194 7 Underground block-caving, exclusively 1948-1952 Underground block-caving and opencut mining 1953-1954 Underground block-caving, opencut mining, and "glory-hole caved-block transfer" mining 1955 on Opencut mining and "glory-hole caved-block transfer" mining. Major Ore Treatment Methods: 1915-1925 Flotation concentration exclusively 1926-1930 Flotation concentration and ferric sulphate leaching 1931-1955 Ferric sulphate leaching (the so-called "Dual Process" was used for eleven months in 1937 when demand for copper was phenomenal; and the "leach-float" process was used for 24 months in 1942-44 as an expedient to help meet war demands for copper). 1956 on "Dual Process" combining a sulphuric acid leach followed by fine grinding and flotation of the residue from the leaching vats.

Jan 1, 1957

By W. Myron Davy

For more than a decade the use of the metallographic microscope, by mining geologists, for examining ores has been increasing and conclusions founded upon examinations made by it are found in several recent professional papers of the United States Geological Survey as well as in our technical publications. But most mining men have been slow to realize the positive value of this instrument in their daily work. The reason for this condition is not hard to find. The varied applications, the simplicity of preparation, and the methods of studying a polished section of ore have not been widely published. Papers in technical periodicals have been profusely illustrated by photographs of such sections, special refined methods of procedure for laboratory work have been described, and complete and detailed schemes of identifying the ore minerals have been published in book form.1 But simple and easily applied directions and, what, is more important, light, compact, and inexpensive equipment have not been available. The simplest microscope obtainable is intended for laboratory use and is much too bulky for the average field equipment; at present it costs about one hundred dollars for the instrument alone. Methods previously described for polishing specimens have necessitated electrically driven lap wheels, which are found only in permanent installations. It is small wonder that the examining mining engineer, field geologist, resident engineers, and mill men have looked upon the subject as being too involved for the field and have assigned it to the laboratory investigator. The writer has been interested in this question for some time from the viewpoint of his own work. Being handicapped by the difficulties enumerated, he has designed an outfit that has proved very useful. It is described here and its. applications shown in the hope that it may be of equal value to others, and that a start will be made toward popularizing

Jan 8, 1920

By William E. Ford, Edward Salisbury Dana

447. Minerals, as regards their chemical constitution, are either the uncombined elements in %native state, or definite compounds of these elements formed in accordance with chemical laws. It is the object of Chemical Mineralogy to determine the chemical composition of each species; to show the chemical relations of different species to each other where such exist; and also to explain the methods of distinguishing different minerals by chemical means. It thus embraces the most important part of Determinative Mineralogy. In order to understand the chemical constitution of minerals, some knowledge of the fundamental principles of Chemical Philosophy is required; and these are here briefly recapitulated. 448. Chemical Elements. - Chemistry recognizes about eighty sub- stances which cannot at will be decomposed, or divided into others, by any process of analysis at present known; these substances are called the chemical elements. A list of them is given in a later article (452) ; common examples are: Oxygen, nitrogen, hydrogen, chlorine, gold, silver, sodium, etc.

Jan 1, 1922

By Edward A. Sayre

In shaft sinking for cod mines, the cost item greatly influences the method adopted. This holds true especially when soft material must be traversed. The average life of a coal mine is short. This is due either to the limited area of the coal basin or to the great expense of maintenance and haulage underground when the entries are extended a considerable distance from the hoisting shaft. Therefore, the engineer in opening a coal mine is confronted with the fact that the cost must be kept within certain bounds else the venture will prove unprofitable. For this reason he may be prohibited from adopting certain safe, but expensive, methods that are used in sinking caissons for foundations, driving transportation tunnels, or other work of permanent construction. A common method of sinking through difficult ground employs the aid of a steel shoe pushed ahead of the shaft timbers. Another is the drop-shaft method. These two methods were used in sinking the main shaft and the air shaft of the Eagle No. 3 mine, at Des Moines, Ia., and the following data show the relative success and cost of the two methods of sinking under the same conditions. A drill log of the material to be penetrated was as follows (see Plate 1, Fig. 1): Thickness, Total Depth, Ft. In. Ft. In. Drift................................... 38 38 Sand..................................... 2 40 Drift.................................... 2 6 42 6 Jointed clay.............................. 5 6 48 Drift, firm............................... 10 6 58 6 Clay, with sand streaks.................... 3 61 6 Sand.................................... 12 73 6 Shale, with two thin beds of coal and thin strata of rock......................... 86 6 160 Rock.................................... 5 165 Coal..................................... 3 9 168 9 Main Shaft Sunk by Steel-Shoe Method This record shows the first 73 ft. to bc of drift material, the lower 12 or 15 ft. of which was sand. The remaining 92 ft. to the coal was shale and rock, and offered no trouble in sinking.

Jan 1, 1917

By Foster J. Witthauer

First mining operations in the Tyrone District, located just north of the Burro Mountains in Grant County, New Mexico, commenced in the 1870's. A major operation was undertaken by Phelps Dodge Corporation in the early 1900's when a 2,000 ton per day underground mine was developed and a gravity concentrator was built east of the mine and across the Continental Divide. It was during this time that the picturesque Tyrone townsite was built and occupied. In 1921, however, the underground operation was closed because of high operating costs and low demand for copper. The area was drilled extensively during the 1950's and in October 1966 Phelps Dodge announced the pending development of the new Tyrone with a large open-pit mine, a modern concentrator, suitable support facilities, and a new townsite to be located between the mine and Silver City. Stripping for the pit and construction of shop and milling facilities began in 1967. By the spring of 1969, ore was being stockpiled near the primary crusher. Operation of the concentrator on a 3-shift per day basis commenced on July 17, 1969. The concentrator as initially built had one primary, two secondary, and five tertiary cone crushers, two grinding sections of six ball mills each, two flotation sections, four filters, and four tailing thickeners. The capacity was about 30,000 tons per day. In 1971 and 1972, the capacity was increased to 48,000 tons per day by the addition of one secondary and two tertiary crushers, one section of eight ball mills, one flotation section, two filters, and four more tailing thickeners. Centralized automatic control was built into the original and expanded facilities to the greatest extent possible, considering the state of the art at that time. Installation of additional control

Jan 1, 1976

[ ] Thomas C. Baker, Jr., has been transferred by the American Manganese Steel Div. of the American Brake Shoe Co., from their Oakland, Calif., branch to their Cleveland, Ohio, office. He will represent them in Ohio and Michigan. William H. Carson, has been appointed district manager of Goodman Mfg. Co's. Huntington, W. Va. sales office. He succeeds Morris W. Highland, granted a leave of absence for health reasons. Mr. Carson, a graduate engineer of Michigan College of Mining & Technology, has been a member of the company's Huntington sales force since 1939, the past two years as assistant district manager. James Parnell Caulfield, former general manager of the Utah Copper Div. of Kennecott Copper Corp., has been appointed assistant general manager of Kennecott's Western Mining Div. L. F. Pett, general supervisor of operations of the Utah Copper Div., was named Mr. Caulfield's successor as general manager. William D. Charles, on completion of his graduate studies at the Massachusetts Institute of Technology, accepted the position of mineral engineer with American Cyanamid Co.

Jan 1, 1952