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By J. W. Downey, M. V. Nevitt

DURING the course of the present investigation of alloy phases involving transition metals, phases were found in the systems Os-Ta, Os-W, and Ir-Ta. The (Os, W) phase was also recently reported by Raub.1 Pertinent information is given in Table 1. The approximate composition range of sta- bility was determined metallographically on arc-melted buttons that were annealed 72 hr at 1200°C and water quenched. X-ray powder patterns were obtained with a 114.6 mm diam powder camera using filtered copper radiation. The composition for (Os, W) given by Raub (66 atomic pct W) is in agreement with the composition range reported here. However, the lattice constants reported by Raub are: a0= 9.913±0.007, c/a= 0.515. The reason for the discrepancy between the lattice constants reported by Raub and those given here is not known. Acknowledgments The authors wish to thank M. H. Mueller and H. W. Knott for assistance with the X-ray diffraction work, and R. A. Morris for the preparation of the alloys. This paper is based upon work performed at the Argonne National Laboratory under the auspices of the Atomic Energy Commission.

Jan 1, 1958

By R. Bakish, W. D. Robertson

IN the course of a study of stress corrosion cracking of AuCu,, it was necessary to develop new electropolishing and metallographic etching methods. The techniques are generally useful for Cu-Au alloys, including the AuCu composition in which transformation markings are well delineated. For electropolishing, the only satisfactory electrolyte and procedure that has been found1 has the composition given in Table I. The solution must be vigorously stirred while polishing and the temperature maintained in the range of 55" to 62°C. The electrolyte is very unstable and can be used only for 10 to 15 min after which its color changes and a dark-brown precipitate forms. The polishing time is between 1 and 4 min depending on the initial surface preparation. The use of a hood is recommended to avoid the danger of cyanide gas which may form at one of the electrodes even though the solution is alkaline. The optimum current and voltage conditions for vertical anode and platinum cathode are on the plateau shown in Fig. 1, in which voltage is measured across the cell terminals. At voltages below the plateau, etching of grain boundaries occurs and under some conditions, which have not been clearly defined, octahedral etch figures are observed. For general purpose grain-size determination in polycrystalline alloys, a 3 pct solution of iodine in methyl alcohol is used with excellent results. However, when it is necessary to reveal small orientation differences or concentration gradients in an alloy, the iodine etch is not satisfactory. For this purpose, a highly satisfactory etching procedure was developed during this investigation. It involves the use of the vapor given off by freshly prepared aqua regia. The solution employed is 3HC1 to lHNO, which decomposes in accordance with the reaction HNO, + 3HC1 = NOCl + 2H,O + Cl,. The polished specimen surface is held about 1 to 2 cm above an aqua regia solution for 2 to 10 sec depending on the intensity of the contrast required and the surface is not subsequently washed. The results obtained with a coarse grained cast structure are shown in Fig. 2. Subgrain boundaries in a single crystal and concentration gradients within the boundaries are developed by the same treatment with the results shown in Fig. 3. Obviously, any conclusions regarding structure-dependent properties will be modified by the pronounced heterogeneity, which is not clearly evident when more conventional methods are used. Interesting structural details are also revealed by treatment for 4 hr at 850°C in unpurified tank argon. Fig. 4 shows a pattern characteristic of orientation-dependent oxidation.

Jan 1, 1956

By Elmer W., Pehrson

NOT much serious consideration was liven to the military aspects of raw materials before World War 1. Following the outbreak of war in Europe in 1914, however. this situation was promptly changed. Disruption of allied shipping and German submarine warfare soon cut off a substantial part of the material the United Staten was accustomed to receiving from overseas. At the same time, raw material requirements rose rapidly as the tempo of industrial preparedness was stepped up in anticipation of war. By April 1917, when we entered the war, serious shortages threatened and consideralde attention was being given to our "deficcient" raw materials. The term "war mineral," began to appear after we became active combatants. But there is no evidence that "strategics" and "critical." as now used, had entered the lexicon of our raw materials experts during the last war nor were there apparently any officially recog¬nized list or definitions of what con¬stituted war materials. According to G. A. Roush in his book, `'Strategic Mineral Supplies," C. K. Leith, while serving as mineral advisor to the War Industries Board. compiled the first unofficial list of deficient minerals in 1917.

Jan 1, 1944

Organization Place Date 1913 Mining and Metallurgical Society of America New York, N. Y. Jan. 8 American Institute of Electrical Engineers New York, N. Y. Jan. 11 American Society of Civil Engineers New York, N. Y. Jan. 22-25 American Society of Heating and Ventilating Engineers : New York, N. Y. Jan. 22-25 American Institute of Mining Engineers New York, N. Y. Feb. 18-21 National Society for Promotion of Industrial Educa- tion New York, N. Y. Feb.. American Institute of Architects Washington, D. C. April American Iron and Steel Institute New York, N. Y. May New York Electrical Society New York, N. Y. June National Association of Stationary Engineers Cincinnati, 0. Sept. American Chemical Society Cleveland, 0. Sept.

Jan 1, 1918

G. M. TAYLOR,* Colorado Springs, Co1o.-I do not think the plan outlined in this paper would work at Cripple Creek. Most of our men have had a pretty good education. The Cripple Creek district is a lessee district-I do not think there is one mine operating in Cripple Creek to-day that does not have the leasing system. We have as many men leasing on our property as we have mining and every plan who is working for wages is looking for n lease-everyman has mined for him- self, he has been his on7n boss on n lease, either on our own property or

Jan 1, 1919

By W. C. Hagel

In 1952, Hauffe and pfeiffer1,2 reported that parabolic rates of nickel oxidation are decreased by factors of two and four at 1100° and 1000°C, respectively, when Li2O vapor is present. Hauffe 's3 explanation was that monovalent lithium enters the crystal lattice of p-type NiO to decrease cation-vacancy concentration and, hence, diffusion of Ni2+ ions across the growing oxide. After first succeeding in adding lithium directly to molten nickel, the purpose of this investigation was to determine whether alloyed lithium is a more effective oxidation inhibitor than the external vapor. Seven 650-g heats were prepared by melting carbonyl nickel inductively under 1 atm of argon. Various amounts of lithium were added by dropping small chunks into the melt. Only about 10-pct recovery was achieved with the remainder lost by spattering and volatilization. Nominal and actual

Jan 1, 1965

By P. B. Liebermann

The resistance to motion offered by mine cars is caused principally by: Rolling friction, flange friction, bending rails, bearing friction and wind resistance. With proper construction and with a fair amount of attention and care, that is, under favorable conditions, the first three items cannot be greatly improved. The wind resistance ordinarily is negligible on account of the slow speeds commonly used. The bearing friction, however, is a variable item, depending upon the design, the bearing material, the lubrication, the location (whether in wheel-hub or on car-body) and the alignment. Under the most favorable conditions the bearing friction will reach a lowest possible value. By the development of a successful anti-friction mine-car bearing this lowest value has been improved to such an extent as to affect the whole system of mine haulage. After being satisfied of their durability and certainty of operation, any investigation into the advantages of anti-friction bearings for mine cars will have to be based upon reliable information as to the saving in power of such bearings. While numerous tests have been made in this direction, the results have not always been convincing, principally because of the rather crude methods that were employed. These crude methods are the main cause of the wide variations existing in regard to the exact amount of the frictional resistance. Frequently an ordinary spring balance is used and the pull necessary to move a certain car or train of cars is obtained by a number of readings. Such spring balances necessarily have a coarse graduation and the continuous vibration and fluctuations to which they are subjected make them highly dependent upon the individual observer. Further, they must be frequently calibrated. Sometimes these tests were made without regard to acceleration, speed or even grade. The method of using an electric locomotive as a testing device is perhaps more open to criticism than the spring-balance method, because it introduces additional sources of error: The varying electrical and mechanical losses in the locomotive. Also, such a measurement always includes the power necessary to move the locomotive itself. This means a considerable amount of figuring, and the results due to the various multiplications and corrections may be of little value, for obvious reasons. When figuring the drawbar pull from the electrical

Jan 1, 1917

By AIME

BORN in 1899, in Bridgeport, Conn., E. A. Anderson grew up in a center of the nonferrous metal industry. Perhaps that had something to do with his selection of mining as a career while an undergraduate in Yale. After securing his Ph.B. in mining he worked for a year at Handy & Harman. By this time physical metallurgy had supplanted his interest in mining and he entered the Yale graduate school where he secured his M.S. degree in metallography under C. H. Mathewson. After completing his graduate work he entered the employ of The New Jersey Zinc Co. in their research division where he has remained ever since. The transition from graduate study to industry involved no disruption of technical interests. Academic research relating to the zinc-aluminum alloys, then coming into use for die-casting, was followed by extensive and productive industrial research in the perfection and commercialization of these alloys. Research on rolled zinc and rolled zinc alloys, corrosion and stress corrosion, dry cells, electroplating on zinc, and electrodeposition of zinc followed in overlapping succession as time passed.

Jan 1, 1947

By W. E. Mitchell

The ore that is being treated by the present plant lies between the leached zone, or capping, and the mixed sulfide and oxide zone. The principal copper minerals are chalcanthite (CuS04.5H20), brochantite (CuSO4.3Cu (OH)2 and atacamite, (CuC12.3Cu (OH)2). There are, in addition, some other minerals such as cuprite and kröhnkite (CuS04. Na2S04.2H20). These minerals, with many others, occur in a greatly crushed granodiorite rock. most of the copper-bearing minerals occur in the cracks and veinlets, but there are disseminated values and it is probably the relative proportion of these that accounts for some otherwise unexplainable variations in extraction. The entire mineralization of the ore is complex and varies with depth. This variation, the problems presented thereby, and the effect of various constituents of the ore will be taken up in detail. An analysis of :in unweighted composite of the ore treated during 1927 follows: I'Lr Cent. Per Cent. Per Cent. Cu............... 1.58 S................. 2.10 Mo............ 0.01 SiO? ............. 66.10 HNO3 ........0.03 As............ 0.005 Fe.......... 1.41 C1 .............. 0.05 Sb............. 0.005 CnO ..... 0.20 Na................ 0.80 Ba............ 0.01 A1203 .......... 17.70 KI.............. 4.80 H20............ 0.70 mgO.............. 0.68 Mn............... 0.07 0 in sulfates. . . . 3.94 Total..... 100.19 The most important constituents of the ore, as indicated by experience to date, are: (1) The total copper content; (2) the acid-insoluble copper; (3) the acid-making copper mineral, mainly the chalcanthite; (4) the chlorine; (5) the nitrates; (6) the soluble iron; (7) the soluble molybdenum. The total copper content needs no discussion. In Table 1, the values are weighted averages calculated from individual charge analyses. The acid-insoluble copper directly affects the extraction, as the present leach recovers practically no acid-insoluble copper. In Table 1 the values are unweighted averages of the analyses of monthly composite samples. The acid-making copper mineral affects the amount of copper that can be dissolved from the ore without neutralizing acid in the solution. The

Jan 1, 1930

By R. H. Cox, A. S. Allen, James Paone

The southwestern Illinois communities of Belleville and Maryville lie within the greater metropolitan area surrounding St. Louis. Missouri. They also lie within that part of the Illinois coal basin where the Number 6 coalbed has been mined for more than a century. About half the coal was left as pillars to support the ground surface. Years later, however, damaging movements are affecting buildings, streets, and public utilities in some areas. They are generally believed to be related to abandoned mine workings. The threat of continued or increasing incidence of damage raises the need to explore other subsidence-control measures for protecting affected areas with high population density. Because of experience gained in a subsidence-control program of backfilling abandoned coal mines in the Applachian region and in Rock Springs, Wyoming, the Bureau of Mines was called upon to investigate the subsidence occurrences at Belleville and Maryville, and recommend protective measures. Funds ware appropriated for the Bureau to initiate subsidence-control projects at two residential sites in Belleville and one in Maryville. Subsurface investigation of the sites by diamond core drilling revealed two conditions that differ from those encountered at most sites of previous subsidence-control projects. The mine workings were found to be dry and the mine floor consisted of soft underclay which characteristically loses strength with increase of moisture. It had been anticipated that water would have percolated into the mine workings at one .or more of the sites through cracks resulting from subsidence. Under such conditions Bureau engineers believed that injection of mine waste by the pumped; slurry technique3 would provide support and stabilize any movements initiated by the softening of the clay. With discovery that the underclay deposits at the three sites have apparently not been exposed to water since the mines were operating, hydraulic backfilling of any type was considered inadvisable on the basis of present knowledge. To avoid introducing water, a portable pneumatic system is being devised for injecting minus 0.01 27 m (1/2 in.) mine waste into the mine workings. Machines for pneumatic backfilling have been used in Europe not only for subsidence protection but also for strata control, for reducing spontaneous combustion and methane accumulation, and as a means of waste disposal. The Bureau experimented with a pneumatic machine in the Northern anthracite field of Pennsylvania in the 1950's. Previously pneumatic machines have been installed in active mine workings discharging from horizontal pipelines which conveyed air- borne material into rooms to be filled. In the present adaptation to abandoned mines, the machine and air compressor will be operating at the surface, to impel material vertically down injection boreholes with sufficient air pressure to disperse fill material laterally in mine workings at the base of injection holes. Large diameter access and ventilation boreholes will be provided at one site for entry into mine workings to observe backfilling progress. The Belleville and Maryville projects are part of the Mined Land Demonstration Program of the Bureau of Mines. The Illinois State Geological Survey and Department of Mines and Minerals are furnishing technical support.

Jan 1, 1979

By C. Burton Clark, J. Spotts McDowell

Refractories are defined as "materials having the ability to retain their physical shapes and chemical identities when subjected to high temperatures," or as "nonmetallic materials suitable for the construction or lining of furnaces operated at high temperatures." While resistance to "high" temperatures is thus the primary requirement for refractory materials, it is by no means the sole requirement. They must be able to withstand thermal shock resulting from rapid heating or cooling; other stresses induced by temperature change; pressures from the weights of furnace parts or contents; mechanical wear (abrasion) resulting from movement of furnace contents; and chemical attack by heated solids, liquids, or gases. Refractories of many kinds are needed for the many and widely diversified industrial applications. Those in greatest demand are classified on the basis of composition or properties into a few main groups, known as alumina-silica, silica, basic and insulating refractories. In each of these groups there are several classes. In addition to those included in the main groups, there are various special refractories, including silicon carbide, carbon, zircon, zirconia, alumina, and several others. Alumina-silica refractories comprise two main divisions: fire clay and high-alumina. The alumina content of fire-clay refractories covers the range from about 45 pct to 18 pct, and the silica content from 50 pct to 80 pct. The alumina content of fired high-alumina refractories ranges from about 99 pct to 45 pct, and the silica content from about 0.5 pct to 50 pct. Silica refractories of the different classes contain 94 pct to 97 pct silica. Basic refractories include periclase (magnesite), chrome spinel, forsterite, and dolomite. Refractory materials, including insulating firebrick, are supplied mainly as preformed shapes. Other products include bonding mortars and high temperature cements, ramming mixtures, plastic firebrick, hydraulic setting castables, dead-burned grain magnesite, and dead-burned dolomite. Refractory brick are classified on the basis of their physical form as Standard Sizes and Special Shapes. The Standard Sizes are brick of certain definite sizes and relatively simple design which are used in sufficient amounts to permit quantity production. The brick most widely used are the standard 9 in. X 4 ½ in. X 2 ½in. and 9 in. X 4½in. X 3 in. straights and corresponding series of sizes. All brick of nonstandard dimensions are regarded as "special shapes." They include a wide variety of brick regularly used for specific services, such as baffle tile for boilers, checker brick for regenerators, and others; together with shapes of special design manufactured on particular orders from designs submitted by the user. Not included in the broad classifications of Standard Sizes and Special Shapes are several specific-service refractory products, usually made by companies which specialize in their manufacture, or in some cases by the consumers themselves. These products include

Jan 1, 1960

Members whose deaths were reported from April 7, 1924 to April 7 1925 Elected Died 1923 ANDERSON, ANDREW ELMER 1924 1919 ANDERSON, JOHN EDWARD 1924 1923 BENKISER, WILLIAM JACOB 1924 1900 BROOKS, ALFRED H 1924 1900 BROWN, CONY T 1925 1910 BROWN, GILMOUR E 1924 1894 ChAPPELL, HOWARD F 1924 1882 CLARK, W A 1925 1918 CLEAVES, DANIEL LUNT 1924 1883 COLBY, ALBERT LADD 1924 1886 CORNING, C R 1924 1911 CRABTREE, FRED 1925 1875 CREMER, J H 1924 1921 CRONIN, JAMES 1925 1904 DANIEL, WILLIAM B 1924 1891 DOUGHERTY, JOHN W 1924 1920 ESCARDO, HECTOR FLORENCIO 1924 1921 FRANK, PAUL MELVILLE 1924 1920 GILES, ROBERT 1924 1922 GILLETTE, LEWIS SINGER 1924 1918 HARRIS, J W 1924 1902 HARTMAN, T F 1923 1912 HERRMANN, CHARLES E 1924 1892 HILLES, JOSEPH T 1924 1882 HOFMAN, H O 1924 1905 HOVEY, EDMUND O 1924 1923 KIME, EDWIN R. 1924

Jan 1, 1923

By W. C. Knopf, G. Samsel

For several years International Minerals & Chem-ical Corp. has used a radiation method to assay potassium content of products from potash and feldspar beneficiation. The procedure is rapid, accurate, and inexpensive and is easily handled, if necessary, by nontechnical personnel. Data are presented to show the accuracies that may be expected if the technique is used for control of pilot plants or large-scale plants. Natural potassium is composed of three isotopes —K, K and K. Five other isotopes, artificially produced, have been detected. In natural potassium only the K isotope, with a half life of 1.4x10 years, is radioactive. Its modes of decay are beta and gamma rays, positrons, and x-rays. Only the more abundant beta rays, however, are important in radiation measurements using geiger tubes. Barnes and Salley' measured radiation of potassium salts in solution in 1943. Gaudin and Parnell2 first reported the use of solid salts arranged in a vessel surrounding the ß counter in 1948. Later, Scheel used the method to assay potassium content of various crude and finished potash salts. Experimental: Dip-type Geiger-Muller tubes (TGC-5) supplied by Tracerlab Co. were used in all radiation counting measurements. The tube was encompassed by a glass container about M in. larger in diameter than the tube. This container, which served as a sample holder, was closed at the bottom with a rubber stopper to facilitate removing the samples. Samples were not weighed, but about 40 g of sample were needed for each test. Electrical impulses from the tube were counted on either a Tracerlab scaler or a rate meter. To obviate the need for constant attendance, preset features were incorporated into the scalers, so that at a predetermined time or count the units were automatically deactivated. When rate meters were used, counting rates were read directly from instrument or from a recorder used in conjunction with the rate meter. Each tube was calibrated, according to the manufacturer's instructions, to determine the correct operating voltage to insure reproducible results. A linear calibration plot of percent K2O vs counting rate was also obtained for each tube by recording the counting rate plus background count of several standards of different K2O content chemically analyzed by the chloroplatinate method.' These standards were of approximately the same particle size distribution as samples to be assayed. Specific background count caused by cosmic rays and other surrounding radiation was checked periodically by counting a sample of pure NaCl. Fig. 1 is a representative calibration plot. Assays were determined directly from the standard plot or calculated by subtracting the background count from the counting rate, then multiplying by the slope of the line. Chemical assays of the test samples were made by the Sherril method," a flame photometric technique, or the chloroplatinate method. Data: The radiation assay method has been used for three years by International Minerals & Chemical Corp. in the laboratory and in pilot plants processing ores containing potassium. These dry concentration plants process sylvinite and langbeinite ores at Carlsbad, N. M., and feldspar ores at Top-sham, Maine. Sylvinite ore is predominantly a mixture of syl-vite (impure KCl) and halite (impure NaCl). Contaminants include sulfates, such as langbeinite (2MgSO - K2SO4), kieserite (MgSO H2O), poly-halite (MgSO4.K2SO, 2CaSO, . 2H2O), and slimes. Langbeinite ore is predominantly langbeinite and halite with small amounts of sylvite, sulfates other than langbeinite, and slimes. Several variables, in addition to correct calibration and standardization of tubes, were found to be important in obtaining reproducible results. Particle size distribution of standard samples should be

Jan 1, 1959

Jan 1, 1943

Jan 1, 1943

By M. E. Wadsworth, I. B. Cutler, R. W. Bartlett

The oxidation kinetics of ZrC was studied between 450" and 580°C in oxygen pressures from 6.5 x 10-to 1 atm using a ther mogravimetric apparatus and sized powder samples. Two parallel rate controlling processes were observed. A surface reaction occurring at the ZrC-ZrO2 phase boundary accounted for most of the oxidation and had an activation enthalpy of 46 kcal per mole. The other process, believed to be diffusion of oxygen into the ZrC lattice partially replacing carbon, had an activation enthalpy of 53 kcal per mole. The enthalpy for chemisorption of O2 on ZrC was determined to be —13 kcal per mole. Water vapor in the presence of oxygen accelerated the surface reaction rate. THERE has been little reporting of formal rate studies or attempts to ascertain the mechanism of oxidation of carbides. MacDonald and Ransley1 studied the oxidation of titanium carbide which has the same structure as zirconium carbide, fcc. They observed an initial increase in rate with increasing temperature followed by a rapid decrease through a rate minimum and a subsequent second increase at higher temperatures. The discontinuity in the rate rise was attributed to a phase change in the oxide which changed the rate determining step from the surface reaction at the carbide-oxide interface to diffusion through the oxide layer. Samsonov and Golybera 2 studied titanium carbide and reported that during the initial period of oxidation a dense film of Tic-TiO was formed followed by the formation of less adhering layers of higher oxides. The purpose of this investigation was to study the kinetics of oxidation of zirconium carbide and to attempt to gain some knowledge of the mechanism by which oxidation occurs. EXPERIMENTAL PROCEDURE Measurement of the weight gain associated with the oxidation of ZrC was used to determine oxidation rates. The principal experimental parameters were surface area, temperature, and oxygen pressure. Although moderately sized crystals of ZrC can be grown by the Van Arkel method, the only commercially available ZrC is a powder. In using powders, the surface area must be controlled either by fabricating the powder into a sintered pellet with a measurable surface area, relatively fixed during oxidation, or by using sized unconsolidated powder and applying appropriate geometric considerations to the shape of the grains to correct for their diminishing surface areas as they oxidize. Both techniques involve some difficulties. pellets of binder-free zirconium carbide can be made by hot pressing, but it is difficult to obtain densities greater than 90 pct of

Jan 1, 1963

By B. M. Larsen

IN endeavoring to put the art of the steelmaker on a more scientific basis, as a means of securing closer control of the product, we must be severely critical of the basis of any theory we use. In particular, we must be careful to distinguish between factors that are primary and those of only secondary importance. The concentration relations that determine the slag-metal equilibria, which are usually more or less closely attained, are of course of primary significance, but a clear picture of the whole process requires that the actual rates of the several reactions be taken properly into account. At the high temperature of the steelmaking furnace, all reactions might be thought to be very rapid, but some of them in fact are not; the essential causes of this condition are important to a proper understanding of the process. This paper aims to present, and to justify, the viewpoint that the most significant reaction is the oxidation of carbon in the metal, the progress of which determines the oxygen pressure levels in slag and metal and produces stirring effects, all of which influence the course of the process as a whole. REACTION RATES AT STEELMAKING TEMPERATURES General experience in reaction rates makes it almost certain that at steelmaking temperatures equilibrium is attained practically instantaneously when the reactants are well distributed in a single liquid phase -that is, in the so-called homogeneous reactions. The actual slowness of some of the reactions in the open-hearth furnace must therefore be attributed to a relatively slow rate of diffusion within the slag or metal phase, which limits the rate at which the reactants can meet each other in the liquid steel or at its surface. That the reactions can be made to go with great rapidity, by proper mixing and stirring of the reacting phases, is indicated by the following illustrations: I. In the Bessemer process there is intimate contact between air and the whole mass of metal, and the reactions are complete in a few minutes. 2. Perrin1 has demonstrated that by pouring liquid steel into slag contained in a deep ladle, and thereby producing almost a slag-metal emulsion, the phosphorus or oxygen content of the steel is adjusted immediately. 3. Barret, Holbrook and Woods observed a quite rapid rate of desulphurization when powdered calcium carbide was stirred vigorously into liquid iron. 4. When a spoonful of liquid steel is poured into a mold containing aluminum wire, the formation and precipitation of alumina occurs in the fraction of a second required to freeze the surface layer of the tiny ingot. The first three examples all show that any means of increasing the effective surface between slag and metal and promoting intimate mixture of the reacting phases, thereby obviating the limitation imposed by diffusion, will enhance the speed of the steelmaking process.

Jan 1, 1941

Jan 1, 1959

Paralleling recent experiments in the U. S., the Mines Branch of the Department of Mines and Technical Surveys in Ottawa has developed a laboratory process for recovering cell-grade alumina from aluminiferous shale. Mines Branch Research Report R45 (1959) entitled The Alum-Amine Process For The Recovery of Alumina From Shale by G. Thomas and T. R. Ingraham states " . . . With the recent resurgence in Canada, and in the United States, of attempts to recover cell-grade alumina from clays and shales, the Mines Branch undertook to review certain processes that had been tried with marginal success . . . In particular, it seemed quite possible that some recent developments in organic chemistry, relating to uranium technology, might be utilized for the removal of the last traces of iron from intermediate products to permit the attainment of a satisfactory grade of alumina." This introductory paragraph explains the authors' approach toward development of an alumina recovery process from shale. The following is an abstract of their successful laboratory experiments.

Jan 3, 1960

By H. A. Doerner

METALLURGICAL problems relating to manganese and chromium ores have striking similarities. Ferroalloys, essential to the steel industry, are produced from both ores. Most of these alloys are obtained from imported ores, as domestic deposits have not yielded enough ore of metallurgical grade to meet more than a small fraction of vital needs. A survey of domestic manganese and chrome de- posits reveals numerous small, dispersed bodies of fairly good ore, none of which appears to be capable of yielding significant amounts of marketable products. To stimulate development of such deposits and to increase Government stockpiles, General Services Administration is offering $115 per long ton for limited amounts of chrome ores and $110 per long ton for 48 pct manganese ores that meet metallurgical specifications, with bonuses or penalties for grades above and below specifications.

Jan 4, 1953