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By Thomas G. Murdock

The possible contribution of an improved mineral economy to the further advancement of the lesser developed regions of the world is a vital consideration today. Many of the newly independent countries recognize the problems and the challenge involved in orderly development of mineral resources. Some countries are inventorying resources, planning development, and encouraging local and foreign participation. The Malagasy Republic, composed of the island of Madagascar and the immediately adjacent islands, formerly the French Overseas Territory of Madagascar, is one of the members of the French Community which achieved independence in 1960. It is making real progress towards improving its mineral economy, an effort particularly remarkable considering the generally unfavorable geographic location of the area with respect to world markets and what is, after all, a comparatively sparse economic mineralization in the light of discoveries to date. Most of the development of the Malagasy econorny before independence was fostered by French private enterprise, although the State participated in some ventures. Since independence, the Government has encouraged private investment from a variety of sources through favorable legislation and has indicated that legitimate investment projects that will further advance social and economic programs will be welcome.

Jan 1, 1963

By H. S. Kalman

A table of factors, for rapid, accurate calculation of the volume of pure helium in cylindrical steel containers, is presented. By use of the table the volume of helium in a container, at base conditions of 14.7 psia and 70° F, can be calculated from the observed pressure and temperature of the helium and the known internal volume of the container. The table covers a pressure range from 0 to 4,500 psia in 10 psi increments and a temperature range of 0° to 120° F in 2° increments. The calculation of volume requires a single multiplication, using a factor from the table and the known internal volume of the container. A discussion and evaluation of the accuracy obtainable and a derivation of the formula used (which takes into account compressibility of helium, thermal expansion of steel containers, and the stretch of steel due to internal pressure) are presented. An example showing how the table can be used is given also.

Jan 1, 1963

By Hazel B. Comstock

This materials survey on magnesium and magnesium compounds is one of a series of Bureau of Mines publications designed to serve the needs of Government and industry for comprehensive, up-to-data information on mineral commodities and activities. Magnesium, the world's lightest structural metal, has become a most useful material in airborne and spare vehicles, automotive equipment, machine tools, and consumer products. Use of magnesium ores in basic refractories for iron and steel furnaces has expanded as the production of iron and steel has increased, Progress in converting steel fun cares to the use of oxygen has further increased the use of magnesia and magnesite brick.

Jan 1, 1963

By John C. Machisak

INJURY and employment figures for nonmetal mines and mills in 1959 are presented in this publication. Data for nomnetal mines are presented separately from those for nonmetal mills. The Bureau of Mines is authorized to send questionnaires to the nonmetal mining industry each year requesting their voluntary submission of injury experience and employment data. The voluntary response to these requests has contributed greatly toward the promotion of safety in the industry, and every effort has been made to make the information as complete as possible.

Jan 1, 1963

By John P. Capp

After World War II the Bureau of Mines studied methods of producing synthesis gas including a plan to gasify coal in place. Consequently, under a cooperative agreement with the Alabama Power Co., Bureau engineers directed a series of experiments that were carried out on the property of the Alabama Power Co. at Gorgas, Ala. The purpose of underground gasification of coal, regardless of method used, is to obtain the energy contained in the fuel for use on the surface, without mining in the usual sense of the term. Underground gasification can be described as (1) a process where coal, in place, is consumed by partial combustion with air, oxygen, steam, or any combination of these to produce a low calorific value gas (80 to 300 Btu per cu ft) or (2) a complete combustion process in which air is used to produce a gas containing carbon dioxide, nitrogen, and considerable thermal energy.

Jan 1, 1963

This report, 27th in a continuing series1, describes Bureau of Mines research and technologic work on coal and related investigations during 1962. While the brief discussion in each section of the report presents only the highlights of Bureau work during the year, details of many investigations can be found in publications cited in this text. Other work, reported here for the first time, will be covered in greater detail in later publications. Recent trends in coal research and technology both at home and abroad were reviewed in several publications2. Bureau research, as in the past3, continued to stress improved methods of mining, preparing, processing, and using coal. The program included a wide variety of applied and basic studies for developing information useful to the coal mining industry and the coal consumer while promoting wise conservation and utilization of our coal resources.

Jan 1, 1963

By Ivan F. Avery

DOMESTIC production of carbon black increased 4 percent in 1962 to 2,056 million pounds. Furnace black output was 8 percent, or 132 million pounds, above that in 1961 and accounted for 90 percent of total carbon black production. Channel black output continued to decline and was 55 million pounds less than in 1961. Carbon black shipments during the year totaled 2,082 million pounds and were 5 percent above those of 1961. About one-fifth of these shipments were exported; the balance were sold domestically. An increase of 180 million pounds in domestic sales was partially offset by a decline of 80 million pounds in exports. Total value of carbon black production in 1962 was $145 million. The average value per pound of 7.06 cents was 0.24 cent per pound less than in 1961. Producers' stocks declined 26 million pounds during the year.

Jan 1, 1963

In 1960, the Secretary of the Interior, acting under the provisions of Public Law 454, 80th Congress, appointed a Lignite Advisory Committee to aid in programming research on coal (lignite) of the north-central area. The chairman of this committee is the Secretary of the Interior or his delegated representative, and in all meetings held during 1960 and 1961, the Director of the Bureau of Mines, Marling J. Ankeny, has presided. The members of this committee were R. W. Rovelstad, President, Baukol-Noonan, Inc., Noonan, N. Dak. W. E. Keller, Vice President, Northwest Division, Truax-Traer Coal Co., Minneapolis, Minn. A. M. Cooley, Professor of Chemical Engineering, University of North Dakota, Grand Forks; N. Dak.

Jan 1, 1963

By W. H. Young

THE BITUMINOUS coal and lignite industry increased substantially in 1962, compared with the 1961 figures. The major items of production, consumption, exports, and productivity increased. However, certain key items declined. The steady upward trend in mechanization failed to materialize for the third year; the percentage of total tonnage mechanically loaded remained the same as in the 2 previous years; and the tonnage mechanically cleaned was smaller than in the previous year. The percentage of total production mined by stripping and by augers increased slightly. Most significant was the continued decline in average value and employment. Production.-The output of bituminous coal and lignite in the United States in 1962-422 million tons-was 5 percent greater than the 403 million tons produced in 1961. Production was greater in 1962, owing largely to expanded consumption by the electric utilities and to more exports.

Jan 1, 1963

Jan 1, 1963

By W. J. D. Stone

Many of the common valuable minerals have a magnetic susceptibility which is sufficiently high to render them amenable to magnetic separation. In addition,, many minerals which form the unwanted constituents of an ore can be removed by magnetic means. Magnetic separation in general has suffered seriously from, the lack of a high intensity wet separator. It is only recently that such a separator has become available to the industry. Prior to this, high intensity magnetic separation has been limited to the use of the dry techniques. Since the introduction of the Jones Wet High Intensity Magnetic Separator, extensive test work has been conducted to investigate possible applications. From the investigations conducted and the discussions that have taken place in the industry, it is apparent that the important mineral characteristic of magnetic susceptibility is not receiving the attention that it deserves. Applications for high intensity wet separation are being found in areas hitherto not considered.

Jan 1, 1963

Jan 1, 1963

By James D. Cooper

COMBINED tonnage or natural abrasive materials sold or used in the United States in 1962 was 10 percent greater than that of 1961 and value was 9 percent higher. Production of crude artificial abrasives in the United States and Canada was up 14 percent in volume and 9 percent in value. Value of grinding-wheel sales increased 13 percent, and the value of coated-abrasives sales was up 10 percent. The value of imports and reexports declined, while the value or exports increased. [ ]

Jan 1, 1963

By NIOSH NIOSH

This work explores application of a double alkaline leach method to extraction of alumina from Oregon ferruginous bauxitic materials. The process recovers a greater proportion of alumina from high-silica ores than is possible by a conventional single-leach method. This recovery is accomplished by calcining the ore, removing reactive silica in a preliminary dilute caustic soda leach, and then applying a second leach to dissolve alumina. Ores containing up to 15 percent Si~) 35 percent AI;:) Os, and 30 percent Os were examined. Under conditions of treatment established by experimentation, more than BO-percent alumina extraction was demonstrated. When and if conditions demand the use of low-grade materials, the double-leach process is capable of providing millions of tons of alumina from Oregon ferruginous bauxite.

Jan 1, 1963

By NONE N

Jan 1, 1963

By R. S. Shepard

A quick glance at a-portion of the title of this discussion -'Rolling With The Punch" may immediately lead you to assume that I am about to expound on the so-called manly art of self-defense. So that you will not have been misled entirely we will devote our considerations to a far more important art and if I may, I should like to begin by quoting Vincent Van Gogh. According to a literal translation the artist in describing one of his famous paintings said "these peasants are eating their potatoes with those very hands that dug them from the earth' and put them in the dish". Vincent Van Gogh may not have realized at that time, that he could likewise have been describing what is probably one of the oldest of all arts - the art of Material Handling - an art that man with the aid of science has tried to improve since the beginning of time.

Jan 1, 1963

By E. W. Murbach

The oxidation of uranium carbide by oxygen at various pressures, and by air, has been investigated at temperatures up to 600°C. Arc-melted and cast uranium carbide displays oxidation behavior that appears to be dependent on its treatment after melting. ccReactive" uranium carbide, which results from exposure of freshly melted material to laboratory air, ignites in oxygen at about 275° to 350°C depending on pressure, and in air at about 350°C. The product of the initial oxidation appears to be UO2+.. Continued heating produces U30,. The initial oxidation rate is poportional, roughly, to the square root of the oxygen pressure. The activation energy determined for the initial oxidation reaction is 7.1 kcal, from 400° to 600°C in 10 mm of oxygen. AN investigation of low-decontamination methods for reprocessing uranium carbide reactor fuels is being carried out at Atomics International. One of the reprocessing cycles includes oxidation of the fuel at relatively low temperature (300° to 500°C) and reaction of the product oxide with carbon at elevated temperatures (above 1500°C) to produce uranium carbide. A number of small-scale experiments have been carried out in which uranium carbide was oxidized in air and oxygen at various pressures to measure reaction rates and to obtain other information concerning the oxidation process. In initial experiments with arc-melted UC, ignition was observed at about 275°C in oxygen or 350°C in air. However, similar experiments by Neymark' at 426°C in air showed no ignition. It was soon determined that the difference in oxidation behavior was due to the treatment of the UC following arc-melting. Neymark's experiments were carried out with freshly melted UC while those reported in the

Jan 1, 1963

By C S. Beals

The Dominion Observatory was founded in 1905 and, from the beginning, it work included research in both astronomical and geophysical science. During its first years, up to 1916, the Observatory also included geodetic surveying as part of it scientific program. Although, at the beginning of the century, geophysics did not have the close connection with mineral exploration that it now holds , the founders of the Observatory were men of vision, and they laid a solid foundation for the application of the techniques of geomagnetism, gravity and seismology to an understanding of the Canadian terrain of plain , mountains, seacoasts and shield area . The particular sphere which the Observatory occupies in the field of geophysics has been evolving over a period of many years and it has now a rather definite relation to the work of other government bodies, university science departments and industrial organizations. We have, for example, an over-all responsibility for the regional magnetic mapping of Canada and, as the magnetic field is subject to slow but steady changes, we produce new magnetic maps of the country every five years. These maps indicate the strength and direction of the magnetic field, the variation of the compass and the rate of change of the magnetic elements.

Jan 1, 1963

By Edward J. Adams

In recent years, there has been a shortage of individuals trained in the technical skills entering the mining industry. The university and industry, both indicating their concern, have joined efforts in an attempt to do something about this situation. An example of such an effort is the Pennsylvania State University's Student-Trainee Program in Mining Engineering, now in Its third year. The program is a five-year plan in which six months of schooling and six months of on-the-job training are alternated, climaxed by the student trainee earning a Bachelor of Science Degree in Mining Engineering plus two years of practical experience. The student trainee accepts the work-study plan as a satisfactory method of receiving a thorough education and preparing fog a career in the mining industry. Inasmuch as the work and study-periods are alternated, the trainee has an opportunity' to integrate his practical experience with his academic knowledge. He receives a chance to observe others perform she duties of the profession he is preparing to pursue, and he regards this as an essential part of any such cooperative effort. Even though there are some disadvantages, the trainee feels that the advantages of the program are definitely more decisive.

Jan 1, 1963

By J. M. Roberts, D. M. Barnett

The activation energy required to break a pinned dislocation line away from its condensed atmosphere of impurity atoms is calculated as a .function of applied stress, without neglecting line tension. Reasows are presented for not assuming the effect of line tension to be negligible when considering the problem of freeing a small segment of dislocation from an impurity atmosphere. The dislocation is considered to he pinned at each atomic size along its length and the pinning points are assumzed immobile. The development is a refinement of the origznal cottrell-bilby1 theory. The solution is compared to recent approximations developed by cottrell3 and Haasen5 in which line tension con- IN 1949 Cottrell and bilby1 considered the problem of determining the force required to pull a dislocation away from its condensed atmosphere of impurity atoms. They also examined the effect of thermal fluctuations on this force. The dislocation line was pictured as bowing out in a triangular loop under the action of an applied stress, and the activation energy necessary to free the dislocation from its atmosphere was calculated as a function of stress, line energy, and dislocation-solute atom interaction. siderations were neglected. A qualitative explanation of the yielding process in terms of the activation of Frank-Read sources is presented, but the lack of a realistic solution to the dynamic dislocation problem involved prevents an extension of the model at present. A self-consistent correlation between the present calculations and experimental data for delay time associated with yielding and the temperature dependence of the upper yield stress was made. Favorable agreement was noted. It is concluded that extension of the original Cottrell-~ilby' theory which includes line tension effects can just as well describe the yielding process as other approximations3,5 which neglect line tension. Cottrell and Bilby found the form of the activation energy vs stress curves to be almost independent of the line energy and the interaction energy (i.e., these parameters only affected the activation energy U by a scale factor). A check of the theory was accomplished by comparison with the experimental data of McAdam and Mebs2 for the lower yield stress as a function of temperature. cottrell,3 in 1957, attempted to obtain a simple closed-form solution for the activation energy as a function of stress by linearizing the quartic equation relating displacement of the dislocation line and applied stress. It was argued that since the contribution to the line energy/atomic plane of a dislocation is made by the long-range stress field of the dislocation through a term of the type (Gb3/2p)ln A/ro, where

Jan 1, 1963