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By AIME AIME

LEADING off the Thursday morning session on Non-metallics was C. E. Heinrichs' paper, "Phosphate Flotation, Its Place in the Technology and Economics of the Phosphate Industry." Mr. Heinrichs also presented a closely related paper, "Milling Methods and Costs at the No. 2 Concentrator of the Phosphate Recovery Corporation," by H. S. Martin. The first of the papers points out the great significance of flotation to the phosphate industry, inasmuch as flotation practically doubles the potential recovery, thereby decreasing production costs and increasing reserves materially. The second paper describes three such plants, two of which are in Florida, the third being at Wales, Tenn. Operating characteristics and costs are reviewed. Answering inquiries from the floor, Mr. Heinrichs said that the adoption of a new parallel-shell dryer, from 60 to 80 ft. long, instead of the old single-shell countercurrent dryer, had increased the unit drying capacity over 300 per cent and had reduced the drying cost to less than 25c. per long ton of dried product. The initial moisture is from 15 to 18 per cent and the final about 2 per cent.

Jan 1, 1933

By AIME AIME

AN IMPORTANT innovation in Alabama in the semi-longwall type of coal mining as applied to low-dipping thin seams has been introduced by the Galloway Coal Co., mining the Mary Lee high-ash seam which averages only 26 in. thick. The property is their Mill Creek mine, near Carbon Hill, Ala., in the Warrior coal field. The results, although not final, indicate that roof conditions can be successfully handled by this method without loss of walls, with a rate of recovery much above that possible with the room-and-pillar method, and at the low production cost necessary for this grade of coal. Double cross-headings are turned off a main haulageway on 60-ft. centers and driven 40 ft. wide with thin chain pillars between. These double entries are turned at 525-ft. intervals, leaving a solid block of coal 440 ft. across; that is, from the outside of one pair of headings to the inside of the next pair is 440 ft. The bottom, which consists of hard fireclay, is taken in these entries 8 ft. wide and 4 ft. deep for head room.

Jan 1, 1934

By AIME AIME

REVIVAL of mining in Yavapai County, Arizona, was the topic of a meeting held at Prescott, on Aug. 24 and 25, sponsored by the Mining Committee of the Yavapai County Chamber of Commerce, with the active cooperation of the Arizona Industrial Congress, the Arizona Section of the A. r. M. E., and the Arizona chapter of the American Mining Congress. Three hundred prospectors, small operators, and mining men from all parts of the State were in attendance. All sorts of mining problems were included in the discussion and all the research facilities of the large companies were offered to aid the prospectors and small operators. The meeting was considered one of the most successful held in the Southwest.

Jan 1, 1929

By F. R. Milliken

EXPERIMENTS, in what has come to be known as flash roasting began some ten years ago. The principle underlying the operation was not a new one, but the experimental work started at that time was the first that was carried through to a logical conclusion, followed by construction and operation of a pilot plant, and then full-scale production. For a short working definition, flash roasting may he considered the instantaneous and complete oxidation of finely ground sulphide particles, partially suspended in air or gas, the oxidation reaction evolving enough heat to make the reaction self-sustaining, or nearly so.

Jan 1, 1937

By H. H. Otto

COMPARED with 1939, the year 1940 has seen no material change in the production of anthracite. Many factors seem to indicate a stabilized anthracite production of approximately 50 million tons per year. The present war has stimulated demand in the Cana¬dian and New England markets, which were formerly furnished with a portion of their needs from Great Britain and other European countries. Neither has there been any material change in the "bootleg coal" situation. This problem is more serious in the Southern anthracite field than in the Hazleton, Wilkes-Barre, and Scranton areas. One reason for this is the nearness of the Southern field to the large anthracite markets in Philadelphia, Washington, Baltimore, and Harrisburg. During the past year no new large

Jan 1, 1941

By PAUL M. Tyier

NOW that analytical chemistry has gone so far to debunk early misconceptions about minerals, the fact that the light of exact knowledge still fails to illuminate many dark corners is often overlooked. By combining the skills of the physicist with those of a chemist, the identification of minerals has become an exact science and the presence of even minute traces of impurities and extraneous elements is readily revealed by spectrographic means, Granted that we can learn all there is to know about the composition of a substance and even about its physical propertied (which latter assumption is somewhat far-reaching) it still does not follow that we clearly understood its commercial designation or utility.

Jan 1, 1941

By A. W. WALKER

All branches of production engineering showed steady and definite progress during 1941. Most of it has been of the slower and more conservative type rather than the sensational. To a large degree the changes have been influenced by the expanding war economy, and this tendency will probably be even more marked during the coming year. The stress of the times is placing more emphasis on the principles of engineering and conservation, with the object of obtaining the greatest possible recovery with a minimum waste or expenditure of equipment. Also available material supplies are often being turned to new uses.

Jan 1, 1942

By J. J. Foster

MOST of us will, I think, agree that never before in the history of the coal industry has the human side of our business been so important as today. Since, even in wholly mechanized mining, labor cost is such a large percentage of out total cost we are all deeply concerned not only about the present attitude of our employees but particularly about the future, when the industry returns to a "survival of the fittest" basis. Many things could and should be done about our employee relations in the coal business. Failure to recognize these obligations and do something about them may lead to serious consequences, the least serious of which will be the loss not only of many of our better employees but a large portion of our potential employees, as they graduate from our schools to other in¬dustries. Some of these things should be handled by the industry as a whole whereas others should be done by individual companies. Due to varying conditions and size of organizations it would, at best, be necessary to vary a program to meet the individual needs of each operator.

Jan 1, 1945

By L. E. Young

GERMANY'S recent collapse and the occupation by the Allies of the coal fields of the Ruhr, the Saar, Silesia, Poland, and Czechoslovakia have focused attention on the postwar coal problems of Europe. American coal operators are interested deeply in what is happening in Britain, particularly in the discussion of plans to rehabilitate and reorganize the entire British coal mining industry, as such reorganization will probably determine the place Britain will occupy in the European coal markets for the next few decades. The continuing decline of British out-ut per man-shift, particularly during wartime, has resulted in a most serious effort to determine whether this unfortunate trend is due to the physical condition of the coal seams, poor management, poor engineering and planning, inadequate use of power and machinery, or failure of labor to co-operate with management.

Jan 1, 1945

By Hans Lundberg, Basil T. Wilson, H. Steuart Scott

FOR the benefit of those readers who may not be in close touch with present practices in the geophysical prospecting for ore, brief reference will fiat be made to the advantages and shortcomings of the methods to be discussed. Magnetic and electric methods are generally accepted as the most useful for ore prospecting. By magnetic methods, magnetic intensities that are not normal may be recorded and outlined. From these can he located concentrations of such highly magnetic minerals as magnetite or pyrrhotite, which sometimes occur in such large masses that they are of economic value in themselves. More often. however, these magnetic min¬erals are associated with others, such as copper, zinc, lead, gold, and silver, which, if existing in sufficient concentration and quantity, may constitute valuable ore bodies. It is therefore only when pyrrhotite and magnetite are present in these bodies that the magnetic method can be used to indicate their presence.

Jan 1, 1945

By D. S. Sanders

IN the four mills of the Cerro de Pasco Copper Corp. in Peru, some 3000 tons of complex sulphide ores are treated daily, with four kinds of concentrates produced: copper, lead, zinc, and pyrite, each containing values in silver, gold, bismuth, and some other metals. Copper occurs in the various ores as chalcopyrite, enargite, tetrahedrite, tenantite, bournonite, and chalcocite; lead as galena; and zinc as sphalerite and marmatite. Small amounts of silver and tungsten minerals are also present. The gangue consist mainly of shale, quartzite, calcite, rhodochrosite, pyrite, and pyrrhotite. In general the values are freed with a relatively coarse grind, about 70 prr cent minus 200 mesh being the finest to which the pulps are ground. In Morococha and Casapalca however. sphalerite particles much finer than this contain inclusions of chalcopyrit r. At Cerro de Pasco the silver and gold are present in all sizes of the ground pyrite.

Jan 1, 1945

By Donald H. McLaughlin

ALTHOUGH Cerro de Pasco was well known since the early sixteen hundreds as one of the major silver districts of the Andes, its development on a modern scale did not occur until the first decade of the present century when a syndicate organized by James B. Haggin initiated the enterprise that eventually grew into the complex and widespread operations of the Cerro de Pasco Copper Corporation. Options on a few claims in Cerro de Pasco that had been brought to New York in 1900 came to the attention of A. W. McCune, a mining man from Salt Lake City, who took them to Haggin and soon succeeded in interesting that creative mining financier in the possibilities of the district. James MacFarlane, an engineer well known to both Haggin and McCune, was sent to Peru early in 1901 to make the initial examinations which promptly led to acquisition of a substantial group of claims in the heart of the mineralized area. A syndicate to which Haggin turned over his rights was organized on Feb. 26, 1902 to provide the necessary funds. The original members were J. B. Haggin, who retained a 34 per cent interest, Edward H. Clark (for Mrs. Phoebe Hearst, the widow of Haggin's old associate, George Hearst), H. McK. Twombly, H. C. Frick, D. O. Mills, and J.P. Morgan.

Jan 1, 1945

By NEWTON B. KNOX

PERU, lying south of Ecuador and having common frontiers with Brazil, Chile, and Bolivia, includes over a thousand miles of the Andean mountains. The coastal plain is arid and narrow and the Amazonian jungle region is of interest only on account of its oil and gold placer possibilities. The mountain zone, however, here forms one of the world's most highly mineralized regions. The Peruvian Andes, like their Bolivian and Ecuadorian counterparts, form two distinct chains separated by the great Apurimac and Maralion valleys; but these rivers cut through the Eastern range to join the Amazon drainage, and the central valley is missing north of the passes thus formed by these rivers; the localities where the ranges are joined are aptly called knots. In addition, in central Peru, there exists a third range lying to the east of the first two and separated from them by the Urubamba and Huallaga Rivers. The Eastern range, however, is of little importance to the miner for few metal deposits are to be found therein except for the gold mineralization in the South. In general, deposition of metals in the Peruvian Andes accompanied igneous intrusions which invaded the folded Paleozoic and Mesozoic rocks during the Tertiary; thus the ore bodies are all typical of shallow or moderate depths.

Jan 1, 1945

By Marcus Nadler

WAGES in the United States, in spite of the wage freeze, have increased materially. Overtime payments have become standard practice in almost all industries. Now efforts are being made to place wages on an annual basis, and if this is adopted, it will result in an increase in the cost of production. Organized labor today is more powerful than ever before; union membership is large and steadily increasing, and in many instances membership in the union is a prerequisite to employment. The treasuries of many unions are strong as a result of the large membership and full employment. The unions, therefore, today are in a much better position than ever before to carry on long strikes. Politically, too, the unions are more powerful today than they ever were. On the basis of their strength, one may expect that some of the demands that the labor unions will make in the not distant future will be granted. It is, therefore, quite evident that before long, particularly when the curtailment in war production reaches about 40 per cent, this country will be confronted with a serious labor problem.

Jan 1, 1945

By Fred R. Ingram

FOR the purpose of this discussion, let us consider that the Rocky Mountain region covers the area in the seven Mountain States, Idaho, Montana, Wyoming, Utah, Colorado, New Mexico, and Arizona, and before we discuss the needs of these states, let us define Industrial Hygiene. Industrial Hygiene is that branch of preventive medicine concerned with the protection of health, improvement of efficiency, and prolongation of life of the industrial worker; in short, adult health conservation. It includes in its broad meaning not only the prevention of occupational diseases, such as silicosis, lead poisoning, cadmium poisoning, and many others, but such relative problems as overcrowding, fatigue, and personal and mental hygiene; exposure to abnormal temperatures, pressures, and humidities; ventilation, heating, and lighting. It is a science which requires the combined activity of medical personnel (doctors and nurses), engineers, and chemists to evaluate the exposures and determine the means of eliminating the hazard. The engineer surveys the workplace, takes air samples at the breathing level of the workman, and analyzes the work exposure. The chemist determines in his laboratory the exact amount of toxic material collected in the sample, which represents the exposure of the workman. The doctor must diagnose the occupational disease, recognize its cause, and evaluate the disability. Together, all three must correlate the data obtained and devise efficient methods, medical or engineering or process changes, for controlling or minimizing the dangerous condition and for studying the effectiveness of these measures. The plant doctor, in addition, must aid in the readjustment of the incapacitated worker and provide facilities for prevention. Industrial hygiene, however, is of no avail without the understanding co-operation of management.

Jan 1, 1945

By AIME AIME

Russell B. Paul, Chairman of the Special Committee on Divisional Relationships, presented the interim report of his Committee which was published in the September, 1945, issue of MINING AND METALLURGY and a copy of which is incorporated in the official minutes of this meeting. The following specific actions were taken by the Board of Directors in relation to the six recommendations in the Summary of the Report as published: (1) Mr. Haider, Chairman of the Petroleum Division, presented the formal request of his Executive Committee that the headquarters of the new Secretary of the Petroleum Division be established in Dallas, Texas. After lengthy discussion in which the point was made that the success of this program would depend upon effective co-operation between the Chairman of the Division, the Secretary of the Petroleum Division, and the Secretary of the Institute, the request was approved. The new secretary will be selected by the Division and will be employed by the Institute in the capacity of an Assistant Secretary. (2) The following item in the report was approved:

Jan 1, 1945

By AIME AIME

ANNOUNCEMENT on August 6 of the historic event of dropping an atomic bomb on Hiroshima, Japan, was more dramatic even than V-E day, since that had so long been forecast whereas the bomb production had been the best-kept secret of the war, even though at one time more than 100,000 people had been at work in connection with its production, and some two billion dollars had been spent on the project. Mining men had long been aware of an unexplained abnormal interest in uranium production, and suspected that something of the sort was on foot, while metallurgists were aware that various men of their acquaintance were engaged in some top secret research. The first announcement was soon supplemented by other official releases which told more about the research laboratories for theoretical and pilot studies, and the plants in Tennessee and Washington, but none of them made clear what the modus operandi is of these terrific bombs. Inquiry at Colum. bia University, where Dr. Dunning and his associates had succeeded in 1939 in splitting the uranium atom, and where laboratories known only as SAM have been feverishly active since the beginning of the war, was unproductive, since none of those officially connected with the project could give out anything beyond the official releases.

Jan 1, 1945

By W. W. Fowler

ORIGINALLY designed for copper smelting only, the reduction works of the Cerro de Pasco Copper Corp. have been expanded over the years until now twelve different metals are produced, together with some seven other items which are used locally. Although the total tonnage treated is comparatively modest, as smelting plants go, the variety of operations makes one of the most complex and interesting metallurgical problems in the world. The original plant, at La Fundicion, operated from July 1906 until September 1923. In 1922 a new copper smelter was built at La Oroya, which produced its first copper on Nov. 23, 1922. It is in this plant, greatly enlarged, that metallurgical operations now center. La Oroya is situated at the junction of the Cerro de Pasco Railroad and the Ferrocarril Central del Peru, at an altitude of 12,175 ft.-well over two miles. Many of the various operations stem from two principal smelting circuits which are themselves of conventional types. Copper ores and concentrates are roasted, smelted in reverberatory furnaces and converters, and blister copper produced. Lead ores, concentrates, and other materials are sintered, smelted in blast furnaces to crude lead which is partially fire-refined, and finally electrolytically refined by a modified Betts process.

Jan 1, 1945

By AIME AIME

C. H. BENEDICT, chief metallurgist of the Calumet and Hecla Consolidated Copper Co., has pioneered for nearly half a century. Noted for his ammonia leaching process, lie has Iong been responsible for all Calumet and Hecla mill, concentrator, and reclaination plant flowsheets. His influence has spread far beyond his own organization. lie is dean of Lake Superior metallurgists and has contributed greatly toward raising his specialty-the country over-to an honored profession; not merely an honored profession but a profitable one for industry and the public. The leaching process which he developed in 1912 has, since 1915, produced for Calumet and Hecla 250,000 tons of copper from waste tailings at a cost per pound, in 1929, below five cents. It has yielded profits of $35,000,000. In the war just ended, this process proved the only one adaptable to the recovery of copper from gilding-metal¬clad steel strip, and Calumet and Hecla treated more than 50,000 tons of such scrap for the Government.

Jan 1, 1945

By Karl S. Hughes

ANY one of the mining engineers who spent three years under the benevolent and protective custody of the military forces of His Imperial Nipponese Majesty will admit that he has survived a most disagreeable experience, but our friends here in the States all demand that we tell them something about our thrilling adventure. Many of the younger men who were on Luzon in December 1941 joined up with the Army, either as civilian technical employees or through their reserve officer status. They served through the Bataan and Corregidor defense and had five months of thrills and hardship, if that is what constitutes adventure. Unfortunately, too many of them are not alive to tell their stories. But for most of us, our internment as alien civilians was just one long, drawn-out pain in the neck. Yes, we starved; yes, we contracted beriberi, dysentery, typhus, dengue, and for a while had no quinine to fight the ever-present malaria; but these things are not exciting, neither is the account of them interesting. Our contingent from Mindanao, 250 .in number including 25 mining men, went through one period of starvation at Davao. When the activity of the Allied fleet interfered with the importation of staple foodstuffs, and the natives stopped bringing fruit and vegetables into the market, the food situation became acute, and in December 1943, with stocks in sight and in prospect insufficient to provision their own soldiers, our custodians decided that we must be moved to Manila. The story of that ten-day voyage in an antiquated Jap freighter is too disgusting to tell, but hardly more adventurous than the account of a game of solitaire.

Jan 1, 1945