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By Rodney L. Stone, David S. Cahn

As part of an over-all laboratory and plant test program to determine mixing ad other techniques for a more economic use of bentonite as an iron ore pellet binder, a settling test for measuring the bentonite content within a pellet or a batch of pellets has been developed. Through this test, it has been shown that dry fracture load is directly proportional to bentonite content in batches of pellets, but inversely propor tional to bentonite content in individual pellets of the same batch. This apparent paradox is explained by a negative correlation between a pellet's size and its bentonite content and the fact that large pellets can withstand a higher fracture load than small pellets. In past attempts to characterize green and dry iron ore pellets, the authors found large variations in the results of strength tests on closely sized pellets from the same batch.' Reasons advanced for such variations in the quality of pellets in which the binder is bentonite were the presence of internal flaws and the nonuniform distribution of the binder. Even when resulting pellet strength is good, there is still the question of whether the same strength could have been attained through a more effective use of a smaller amount of bentonite. The authors' own and other studies 2-3 have pointed out the strong dependence of pellet strength on the degree of "mixedness" of the iron ore concentrate and the bentonite binder. However, before such a relationship could serve as a guide for the development of better mixing techniques and the associated economy of

Jan 1, 1969

By Ogden Tweto

The classes of ore deposits in the mountain province of Colorado that have been the most productive in the past and that offer the greatest promise for the future are: (1) disseminated or stockwork molybdenum deposits associated with Tertiary stocks; (2) combination precious- and base-metal veins in Tertiary volcanic rocks; and (3) base-metal replacement deposits and veins in Paleozoic sedimentary rocks. Veins in Precambrian rocks, including precious metal-bearing sulfide veins, gold-silver telluride veins, and tungsten veins, have been mined extensively in the past, but their aggregate output has been far subordinate to that of the groups named above, and the outlook for major output from them in the future is poor. Principal ore deposits of south-central Wyoming are sedimentary iron ores of Precambrian age and uranium deposits in Tertiary sedimentary rocks. Precambrian deposits of several kinds are scattered through the mountains of both states. The most promising of these, based on present indications, are vanadiferous titaniferous magnetite in southern Wyoming and southwestern Colorado and thorium-niobium rare-earth deposits associated with alkalic intrusive complexes in Colorado. Most of the mining districts of Colorado are in the Colorado mineral belt, a generally narrow but somewhat irregular belt that extends northeastward across the north-trending mountain ranges and the north-northwest trending geologic grain of the state. The belt is characterized by intrusive rocks of Laramide and younger age and by ore deposits, and it occupies environments ranging from Precambrian crystalline rocks through Paleozoic and Mesozoic sedimentary rocks to Tertiary volcanic rocks. Two ages of intrusion and ore deposition recently have been recognized in the mineral belt. One is Laramide (late Cretaceous and early Tertiary), and the other is Oligocene. As interpreted herein, the major replacement deposits and most of the sulfide vein deposits in Precambrian and sedimentary rocks are Laramide in age, and the molybdenum deposits, the tungsten and the gold telluride veins in Precambrian rocks, and the precious- and base-metal veins in volcanic rocks are Oligocene in age. In general, the Laramide deposits are mesothermal in aspect, and the Oligocene deposits are principally epithermal. The existence of two mineralization stages, in considerable part characterized by different suites of metals, has many applications in exploration.

Jan 1, 1968

By AIME AIME

WHETHER by the Mohawk Trail, Sound steamer, air plane, railroad or any other route or mode of locomotion, all roads will lead to Boston the week of National Metal Congress, Sept. 21-25. The Institute of Metals and Iron and Steel divisions of the Institute are then to meet jointly at the Hotel Statler, and the American Society for Steel Treating, the American Welding Society, the Society of Automotive Engineers and the Iron and Steel Division of the American Society of Mechanical Engineers present carefully planned programs at their respective sessions. The National Metal Exposition will be held on Commonwealth Pier.

Jan 1, 1931

By Lord Marley

ACTIVE participation by the United States in the war acted as a stimulant on the Annual Institute Meeting in New York rather than a retardant as feared. Attendance was about 10 per cent under the all-time high reached last year, but considering the number of men who could not possibly come because of active military service and the additional number who are devoting their whole time and effort to turning out vital war materials, the registration was really greater than might have been expected. But all in all the Institute put on a show that taxed the capacity of the Engineering Societies Building as well as the capacity of the visitors to find time to attend everything that promised to be of interest.

Jan 1, 1942

By H. Herbert Hughes

ECONOMISTS have predicted that the present business depression ultimately may pay big dividends to industry through the cumulative savings resulting from technical improvements and merchandising advances that might never have been developed under normal conditions. Waste prevention is a sound medicine for economic ills. In theory, this prescription may be applied not' only to raw materials, but also to labor, fuel, over- head, and other phases of production. Actually, how- ever, regardless of the efficiency of operating practices, waste is inevitable in the production of many commodities. The problem then becomes one of profitable utilization of waste rather than prevention.

Jan 1, 1932

By Charles W. Merrill

Obsolescence in the mineral world is virtually nonexistent if the term is taken to mean that a mineral commodity, once established in commerce and industry, subsequently has fallen into disuse. We are living in an age of minerals. Each generation puts an increasing array of mineral-based commodities, in larger quantities, to more uses than ever before. Bastnasite, a museum mineral and a collector's item a few years ago, is now produced in quantity at Mountain Pass, Calif. Uranium, a minor byproduct of vanadium mining in the Rocky Mountain plateau area before World War 11, has grown to be a leading mineral product in several western States. And finally the total quantity and value of minerals both in the United States and in the World establish new records almost yearly. Surely the mineral industry as a whole is not obsolescent in our economy. Nevertheless, there are particular uses for particular minerals that are obsolescent and some applications have been supplanted entirely. Tin does not occupy the prominent place in foil manufacture that it once did, and the schoolboy's slate left most classrooms before the oldest of us were born.

Jan 9, 1964

By Howard R. Pratt, Jimmie L. Bratton

The Air Force Weapons Laboratory (AFWL) has been carrying out a series of experiments whose principal purpose is to measure the dynamic response of rock media to large pressure pulses. Coupled with the field experiments have been theoretical calculations simulating this response. These two approaches allow an appraisal of the current ability to measure in-situ rock response under extreme conditions and also give a fair estimate of the current state-of-the-art in the area of computer calculation of the response of "real" geologic media to a large load. The area chosen for the test series is composed of a sequence of sedimentary units (shale, sandstone, and limestone) located in the Estancia Valley 45 miles east of Albuquerque, N.M. (Fig. 1). The units, which dip gently off the uplifted Manzano Mountains to the west, are essentially horizontal at the test site. An extensive geologic and geophysical investigation of the area was carried out in the form of surface mapping and seismic exploration. Numerous holes were cored and material properties were determined from tests of the cores. In-situ geophysical measure¬ments were also carried out. The experiment consisted of loading a 60X40 ft test area with a 4000-psi transient exponentially decaying pressure pulse. The pulse was initiated at one end and traveled the 60-ft length of the test bed. The test area was instrumented with acceleration, velocity, and strain measuring devices placed in drill holes to depths of 30 ft. Theoretical computer calculations of the response of the layered geologic media have been carried out on the AFWL CDC 6600 using one and

Jan 1, 1972

By AIME AIME

A CORPORATION would go into bankruptcy if its affairs were conducted as are those of the state of New York, according to the Committee on New York State Government Reorganization of the American Engineering Council of the Federated American Engineering Societies, in a report to the chairman, of the Joint Judiciary Committees of the Senate and Assembly. The report, just made public, was signed by the three members of the committee who were appointed by Herbert Hoover. They were H. de-B. Parsons, chair- man, Paul G. Brown and Lewis B. Stillwell. Although the American Engineering Council is a national organization, it decided to aid in governmental reorganization in New York State because of the magnitude of the task. The Council's committee in its report urged the passage of three state reorganization amendments for consolidation of departments, an executive budget system, and a four-year term for the higher state officials. In the words of the report :

Jan 1, 1921

By Joseph Hyde Pratt, Douglas B. Sterrett, CHAPEL HILL

I. DESCRIPTION. MONAZITE is one of the minerals which, for a long time, was considered rather rare in its occurrence, but, upon a commercial demand arising for it, prospectors and engineers soon located large deposits of it in the Carolinas and Brazil, and the supply has always been able to meet the demand. During 1908 further sources of supply of monazite have been discovered and developed in Idaho. North and South Carolina, however, are the only States that have thus far put any monazite on the market. Monazite is essentially an anhydrous phosphate of the rare-earth metals, cerium, lanthanum, and didymium (Ce, La, Di)PO;. There is nearly always present a varying but small percentage of thoria, ThO2, and silicic acid, SiO, which are very probably united in the form of a thorium silicate, ThSiO4 Some monazites contain but a fraction of a per cent. of thoria, while others have been recorded that showed the presence of from 18 to 32 per cent. ; but the majority contain from 3 to 9 per cent. of this oxide. It is the presence of the thorium oxide that gives the monazite its commercial value. The analysis occasionally shows also the presence of other constituents, as the yttrium and erbium oxides, zirconia, alumina, magnesia, lime, iron oxides, manganese oxide, and titanium oxide. Monazite is light-yellow, honey-yellow, reddish-, brownish-, or greenish-yellow in color, with a resinous to vitreous luster, and is translucent to subtransparent. It is brittle, with a conchoidal to uneven fracture, and is from 5 to 5.5 in hardness, and from 4.64 to 5.3 in specific gravity. It crystallizes in the monoclinic system, and some crystals have been observed that were 6 in. in length. The more perfect crystals are, however,

Jun 1, 1909

By NEWTON C. MARSHALL

AS every school boy knows, the Andes mountain range forms the backbone of South America, extending the full length of the continent along its western edge and fairly close to the Pacific coast. But in Colombia these mountains are divided into three distinct ranges known as the Western, Central and Eastern ranges of the Andes. United at the southern end, they spread out like three fingers in a northerly direction across the Republic of Colombia. These great natural barriers have only in recent years been tarried by railroads or wagon roads, and they have had their effect upon the history of the country, both political and ethnological. Each of the three ranges dies out and dwindles away before reaching the boundary of Colombia on the Caribbean Sea. When I studied my geography as a youngster 1 used to think that the

Jan 1, 1935

By Jasper L. Stuckey

PYROPHYLLITE, first identified as soapstone,1 later as agalmatolite,2 and finally as pyrophyllite,3 has been known to occur in North Carolina for more than 130 years and has been produced intermittently in commercial amounts for the past 100 years. Pyrophyllite mining, however, has become a major industry in North Carolina only during the past 25 years. North Carolina and California are the chief producing states. Current annual production averages 125,000 tons, of which slightly more than 90 pct comes from North Carolina. Distribution and Geologic Setting: All known pyrophyllite deposits in North Carolina are associated with rocks of the Carolina Slate Belt,4 which is composed of a vast series of metamorphosed volcanic and sedimentary materials, occurring as two zones extending in a northeast-southwest direction across the state. The larger of these zones, lying in the central Piedmont region, varies from 8 to 50 miles wide. The smaller zone lies along the eastern edge of the Piedmont region and is partly covered by coastal plain sediments.

Jan 1, 1958

Jan 1, 1971

By Henry Schwellenbach

LABOR shortages, rising wages, and changes in moisture and fines content of the ore necessitated a review of the flowsheet at Warren Foundry & Pipe Co's. Mt. Hope, N. J. Mines Div. This plant had been designed prior to World War II, and started operations in January 1945. When this operation was designed there was an oversupply of labor in the area, wages were at a reasonable level, the run-of-mine ore was low in moisture, and there was a limited amount of fines. These factors all favored use of hand picking for cleaning rougher lump concentrate. Since that time, many changes have occurred. The proximity of defense industries and large military installations, has created one of the most acute labor shortages in the country. This labor shortage together with present wage levels, and the increase in moisture and fines in the ore created several problems. The increase in moisture and fines may be attributed to changed mining methods, the extensive use of sprays, and the opening of new mining areas bringing an increase in ground water. [ ] Two problems were presented by the increase in moisture and fines. The first was that lump ore arrived at the open hearth in an unacceptable condition, due to the segregation enroute of the large amount of fines that had adhered to the lumps. The second problem was that high magnetite content fines coated the large lumps, making it difficult for pickers to distinguish middling by other than the relative weight. [ ]

Jan 1, 1952

By K. Reinhardt

THE idea of burning blast-furnace gases directly in gas-engines, instead of under steam-boilers, as had previously been done, was first put into practice barely ten years ago, almost simultaneously in Great Britain, Germany and Belgium. The pioneers of this movement made their first experiments with small engines. After these experiments had given satisfactory results, and it had been shown that the thermal value of the poor blast-furnace gases, in spite of defective scrubbing, could with safety be directly transformed into mechanical work in the gas-engine, there very soon arose a considerable demand for gas-engines of large power, similar to the large steam-engines employed in metallurgical works. In face of these sudden requirements, the gas-engine builders were placed in a difficult position; for up to that time the gas-motor was considered as suitable for small engines only, and it was generally believed that the limit of size bad been attained with 100 to 150 effective h.p. in a single cylinder. Manufacturers of gas-motors, however, did not underrate the advantages offered by this new field for their manufactures, and it so happened that in Germany the Berlin-Anhaltische Maschinenbau-Gesellschaft, of Dessau, was the first to undertake the construction of a 600-h.p. two-cycle gas-engine, with two cyl¬inders of the Oechelhäuser-Junkers type, for the Hoerder Mining & Smelting Company. The engine was started in 1898, and, with a few improvements and alterations, is still working satisfactorily. This engine worked with astonishingly high of efficiency, considering the period. The builders were therefore

Nov 1, 1906

By John Ward Smith

Dawsonite-bearing oil shale of Colorado's Green River formation offers a unique and vast (more than 5.9 Gt of A120 j) resource of easily extractable alumina. The processing methods required by the thermal reactions of dawsonite and its oil-shale carrier also require production of shale oil, soda ash, and nahcolite as marketable coproducts. These production methods are presented. The alumina production process is contrasted with the Bayer process to describe technical advantages of extraction of alumina from oil shale which may offset the problems associated with processing a relatively lean ore. While alumina production from oil shale requires development of new technology, the technical problems appear solvable. Only the political problems arising from the now onerous and completely unnecessary federal oil-shale withdrawal appear less solvable.

Jan 1, 1982

By AIME AIME

IN many countries the lack of liquid petroleum supplies has centered interest upon the hydrogenation of coal and coal tars for the preparation of motor fuel. In the United States, hydrogenation has been of greater interest for grading up low-value petroleum fractions to the more valuable volatile fuels and for the preparation of a variety of premium products, including aviation gasolines, solvents, Diesel fuels, and lubricating oils. Chemically, the basic reason for this process is that, as shown in Table 1, the ratio of hydrogen to carbon (H/C ratio) in available raw materials is quite different from that characterizing the products sought.

Jan 1, 1936

Carlisle: An old friend and good friend, Alan Bateman, is the Silliman Professor of Geology Emeritus at Yale and editor of the Journal of Economic Geology. Now, Alan, let's start off by telling us something about how you became interested in copper. Bateman: Well, after I left Yale in 1913, I was appointed one of the field members of the Secondary Enrichment Investigation. We spent three years in the field studying all the copper deposits of North America, trying to find out how secondary copper enrichment took place. As part of this investigation, I went up to Kennecott, Alaska, in 1916. After the trip I was asked by the president of the company to become consulting geologist to them. I accepted his offer, and to this day I'm still consulting geologist to the Kennecott Copper Corp. Up at Kennecott, there were both Henry Krumb and my good friend Henry DeWitt Smith, who was general superintendent. He and I had been together at Yale, and I had ushered at his wedding. Interestingly enough, Henry took his bride to Alaska and I took mine there two months later. My assistant was Don McLaughlin, and I think that was his first experience in a mining camp. We published a paper on Kennecott together and cemented a friendship lasting to this day.

Jan 11, 1964

By Joseph T. Singwald

INTRODUCTION THE purpose of this chapter is to present the diagnostic features (geologic, mineralogic, chemical, and physical) of the principal types of hypogene ore deposits recognized in current genetic classifications, and to classify the ore deposits of the western United States into those types. The genetic divisions used and the criteria determining them are essentially those followed by Lindgren in his Mineral Deposits. Deviations from Lindgren represent either changed conceptions since 1928 (the date of the third edition of Mineral Deposits) due to advance in knowledge or the inevitable differences of opinion between experts in active fields of investigation. Though nineteen economic geologists have been given free hand in presenting their particular topics, there are no fundamental departures in the chapter from the principles set forth by Lindgren. It would be entirely beyond the capacity of a single chapter to give a comprehensive geologic description of all the ore deposits of the western United States. Descriptions of individual deposits have been restricted to those features that are of most diagnostic genetic value. All of the more important deposits receive that much attention. Deposits of lesser economic importance and those inadequately known geologically are treated more briefly or merely cited under what seems to be their proper genetic assignment. The geographic limits of the descriptive matter are the Black Hills and the United States between the Rocky Mountains and the pacific Coast. Capacity of the chapter has made it necessary to impose these geographic limits.

Jan 1, 1933

By A. KROENLEIN

THE Cromwell 'Pool has been the outstanding development in Oklahoma during the year 1924. . Tonkawa contributed the deep "Slick Sand" bit apparently its 'peak has been reached and like other pools producing from below the Mississippi lime its decline' mill be rapid. After reaching a daily production of 67,000 bbl., the Cromwell Pool is declining because of a lull in -new completions, but a mile extension has revived activity and an area equal to that of the present producing' area is under development and will cause an increase in the present production of 38,000 bbl. This pool is seven months old, has three dry holes in one hundred twenty completions and is actually defined only on the southern extremity. This area has been one of the chief contributors to the .over-production of high gravity oil in the Mid- continent fields and will be such' for the remainder of ' the year. 1924 and first part of 1925.

Jan 1, 1924

By Charles T. Baroch, Charles J. Baroch

In 20 years of commercial development, nuclear reactors have demonstrated that they are a safe, dependable, and economical source of power. Operating experience with commercial power reactors has firmly established nuclear power as a practicable source of energy. For both boiling-water (BWR) and pressurized-water (PWR) reactors, performances to date have generally met design predictions. Furthermore, it has become possible to analyze and understand the nuclear, chemical, and physical behavior of this class of reactors. The United Kingdom has had similar success with gas-cooled reactors. The Experimental Boiling Water Reactor (EBWR), the first United States experimental power reactor, began operation in 1956. It proved to be capable of supplying 4500 kw (kilowatts) of power. This reactor was followed in 1957 by the Pressurized Water Reactor at Shippingport, Pa. It was the nation's first full-scale central-station nuclear power plant and the first in the world designed exclusively for the production of civilian electric power. The Shippingport reactor was originally designed to produce 60 megawatts (MW) of electricity, and it was increased to 100 MW in 1964. In 12 years of operation, this reactor generated over 4.5-million MW-hr of electricity in spite of many shutdowns for experimental alterations. By 1969, a total of 15 central-station nuclear power reactors were operable in the United States with an aggregate electrical capacity of over 4200 MW. Early in 1964, Jersey Central Power & Light Co. announced plans for constructing a 515-MW nuclear plant at Oyster Creek, N.J., to be built without government financial assistance. The company stated that a nuclear plant had been selected competitively with fossil fuel. Their economic analysis stated that the plant would generate electricity at less than 4 mills per kw-hr, competitive with coal at 200 per million Btu (British thermal units). Coal cost in 1964 for that region averaged 26.00 per million Btu. The Jersey Central report created wide interest in public-utility circles; nevertheless, no other nuclear plants were announced in 1964. However, in 1965, six nuclear plants were announced by utilities, followed by 26 in 1966, 29 in 1967, and 10 in 1968. By Sept. 30, 1969, 97 reactors were operable, being built, or planned. The cost of these, all committed by electric utilities, was estimated at about $12 billion. When constructed, they will have an electrical capacity of 72,000 MW. The unprecedented surge in power reactors that started in 1965 tapered in 1968, and only seven reactors were announced in

Jan 1, 1976