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By M. C. Fuerstenau, D. W. Fuerstenau

Long-Chained aliphatic amine salts have been used for the separation of sylvite (KC1) from halite (NaC1) by flotation. It is puzzling how these two minerals, which are so similar chemically and crystallographically, can be separated by this method. Gaudin as postulated that the difference in floatability of halite and sylvite with salts of primary amines depends on ionic size: In the case of amine flotation, the cation would attach itself to the chloride. I have a speculation there, which I cannot prove, that the ammonium group, that is the –NH3 group in the amine, floats potassium chloride because the dimensions of this group as it has been measured in other compounds is almost identically the dimensions of the potassium ion, quite different from the sodium ion, and so it fits where potassium had been, in place of it and not attached to it.

Mar 1, 1956

By J. N. Munro

At the present stage of geothermal technology and the still limited applications of geothermal energy, most of us consider any use of "things geothermal" to be something out of the ordinary. If in such a situation there can be a use of geothermal energy which is even more unusual, then the utilization of geothermal energy-or more precisely, geothermal heat--for the manufacture of salt is just such a use. This is the essence of investigations in the Fiji Islands, where experiments in the evaporation of seawater to product, salt have been conducted using geothermal heat emanating from the ground in an area of hot springs. The hot springs are located on the coast at Savusavu in a depression about GO ft wide. There are ten individual springs, but most of these are small and insignificant. The temperature of the water from these springs reaches 100°C.

Jan 9, 1964

By Carle R. Hayward

LEAD ore smelting plants have been operating in general at reduced capacities and secondary lead has assumed relatively more importance during the last year. Present smelting practice results in a large amount of dross, often over 25 per -cent, from blast-furnace lead. This is usually treated at a fairly high temperature in a reverberatory furnace to remove part of the lead and produce a matte-speiss product which is shipped to a copper plant. Few smelters are satisfied with this 'treatment. The fume losses are high and the matte-speiss contains considerable lead. It would seem that a fruitful field for research was open here.

Jan 1, 1934

In the late 19th century Fremont Pass was only a gateway to Leadville, Colo., 12 miles to the north. Some of the silver, lead, and zinc won from this famous camp crossed the Continental Divide at Climax, passing by the huge outcrop of molybdenum on Bartlett Mountain. This element, relatively un- known in the world of commerce, was then nothing more than a joke to play on greenhorn prospectors. Even 30 or 40 years later, after the demand for metals created by World War I had forced temporary use of molybdenum as an alternate for tungsten in tool steels, the Bartlett Mountain outcrop once again became merely a curiosity. With the persistent efforts of Brainerd Phillipson, for years the president of Climax and almost the only employe, use of molybdenum gradually began to grow, first in tool steel and later in the alloy steels required by the growing automotive industry. Mr. Phillipson was first an engineer and second a salesman. The combination of these two qualities is the key to the story, not only of Climax sales but also of the growth of molybdenum from an object of idle curiosity to the point where it is today, along with chromium and nickel, one of the most versatile alloying elements in the iron and steel industries and increasingly important in chemistry.

Aug 1, 1955

By John Tyssowski

IN 1925, Harry Howard Stout, then metallurgist for Phelps Dodge Corporation, while investigating the cleaning of cathode copper by various gases at elevated temper-atures below the melting point of the metal, observed in the laboratory that particles of pure copper heated in a closed tube filled with hydrogen seemingly "stuck together." By further investigation he found that there was actual crystal growth across the boundaries of the particles of pure metal; in other words, there was a complete new crystal realignment and growth throughout the newly formed copper mass. It was coalescence, not adhesion; the several parti-cles had become one unit. From this dis-covery has been developed the coalescence process, whereby copper of cathode purity is squirted out in semifabricated form from an extrusion press, by the appli-cation of about 3000 tons pressure on a 10-in. piston. Stout decided that cathode copper pro-duced by electrolytic deposition was the logical source of the pure copper required for the coalescence process, but as there was no way of reducing the ordinary tough commercial cathodes to the small particles required he was confronted by a serious problem at the outset. Under his direction, this problem was solved by William H. Osborn and Harry Howard Stout, Jr. They developed the process and technique for producing cathode copper in brittle, friable

Jan 1, 1940

By Charles E. Nelson

In considering the types of scrap that are processed into secondary magnesium, it is important to point out that the greatest proportion of this material is fabrication, foundry and machine shop scrap that is generated during the conversion of magnesium products into the finished article. This material, then, is largely of the same composition and quality as the original ingot or heat of metal except as it may be mixed with other compositions or metals in the fabricating process. Insofar as such materials can be processed back into secondary ingots or final products which meet the composition and property standards required of the original virgin stocks, then it seems reasonable that such products are fully equivalent to the primary products. With these premises then, it is the intent of the present discussion to consider briefly some of the methods whereby scrap may be generated, segregated, shipped, and processed in such a manner that the final products will be equivalent to virgin materials. Some information on the effects of impurities will be given in order to aid in the evaluation of these products. SCRAP GENERATION The method by which scrap is generated serves in a rough way to classify the resulting materials in terms of how they may be handled and recovered. These methods will be dealt with briefly. Machining operations such as milling and turning undoubtedly provide the great-

Jan 1, 1943

By Hermann Bach, Walther Hänig, Willi Gehrhardt, Ernst Theurich, Walter Langner

With the construction of the Magdeburg zinc works, the Georg von Giesche's Erben Mining Co. of Breslau has to a certain extent completed the program of reconstruction which it set as its goal after the boundaries of Upper Silesia were drawn by the Treaty of Versailles. During its history, covering.more than two centuries, zinc and lead mining has been its chief activity. Through the new boundaries established, it lost to Poland all its mines and smelters, including five distillation smelters. Of its extensive properties, there remained only an apparently unimportant and unexplored portion of the old Bleischarley ore field which, however, happily made possible the resumption of its old business. In 1925 the Deutsch-Bleischarley shaft-only a few kilometers from the old Bleischarley shaft—was sunk and developed, and in May 1926 production of lead and zinc ore was resumed. As facilities for smelting were lacking, the ore was at first delivered to the neighboring smelters, which had now become Polish. Realization of the plan to build its own zinc works had to be postponed at first for lack of capital. In the meantime, however, plans for the new works were worked out in all details. After extensive experimentation in a semicommercial pilot plant it was decided, at the end of 1928 and the beginning of 1929, to use the electrolytic process and, for economic reasons, to place the works at Magdeburg. With zinc at the approximate price level that had ruled since the Deutsch-Bleischarley mine had begun working, it was hoped that the plan could be completed in 1930 with the company's own resources. However, falling metal prices, already noticeable in 1929, made this impossible, and further postponement for a time became necessary. Finally, at the end of July 1933, the funds for building the works became available, in the form of a loan granted under the first employment

Jan 1, 1937

By M. K. Yen, W. R. Hibbard

Previous studies of plastic deformation of metals have emphasized the important role of bending and constraints during strain under relatively pure stresses.1"5 Some new phenomena such as early conjugate slip6 and polygonization7 are intimately concerned with the relief of bending stresses, the former by slip and the latter by a process analogous to re-crystallization. However, few analyses of the bending deformation of single crystals were found in the literature, and those8,9 are sufficiently previous to the modern interpretations of slip to invite further investigation in this area. The transverse bending mode of testing, using the two-point loading method, was selected because the center portion of the specimen may be considered as under a theoretically pure bending stress with a uniform bending moment. Considerable attention was given to both the lattice distortion and flow characteristics of the crystals during deformation. Experimental Proeedare A specimen under the action of equal and opposite couples at both ends is said to undergo pure bending. The shear and moment diagrams of a specimen under the two-point loading method of transverse bending are shown in Fig 1. The moment over the middle-third of the span is equal to PL/6, and the vertical shear is zero. Fig 2 (A) illustrates the stress distribution in the elastic range on a plane across the middle of the specimen. It can be seen that the normal stress has a maximum value at the extreme surfaces on the tension and compression sides, and decreases proportionately to zero as it approaches the neutral plane. However, when the plastic range is reached, the stress distribution is no longer a straight line relation, but changes in a manner which can be best illustrated as shown in Fig 2(B). The following calculation and stress analysis are mainly in accordance with the works reported by Timoshenkol0 and Kochendörfer.9 From the simple beam formula, the maximum normal stress will occur at the surface of the specimen. For a round specimen with a radius r and for a rectangular specimen with a height 2h and width 2b, the maximum normal stress, Sp, will be given by the following formulas: For round specimen: 2PL Sp = 3pr3 [1] For rectangular specimen: Sn = 8bh2 [2] Since it is reasonable to consider that slip takes place under the same conditions as in uniaxial loading, the resolved shear stress S?, along the operative slip direction will be as follows: For round specimen: 2PL sin x cos ? Sp = 3pr3 sin x cos ? [3] For rectangular specimen: PL S8 = 8bh2 sin x cos ? [4] where X is the angle between the specimen axis and the slip direction and X, the angle between the specimen axis and the major axis of the glide ellipse. It was also reported by Kochenclorfer9 that the critical bending moment, that is, the bending moment exerted on the specimen to initiate slip, should be higher than the value given by the equations stated above. Based

Jan 1, 1950

By Peter B. Nalle

Over a period of years the Crestmore plant of the Riverside Cement Co. has been supplied with limestone from the Chino limestone bed. The limestone bed dips about 40º and extends 1500 ft along the strike. Thickness of the bed is such that horizontal distance from footwall to hanging wall varies from 400 to 1200 ft. When the new room and pillar mining system was instituted the haulage units used for development were model C Tournarockers. Four of these diesel units were purchased with the idea of using them solely for development work since it was realized that they would have to be supplemented by additional, and perhaps larger haulers.

Jan 4, 1959

NEW MEMBERS The following list comprises the names of those persons who became members during the period Jan. 10 to Feb. 10, 1915: Members AGASSIZ, RUDOLPH Louis, Vice-Pres.,Calumet & Hecla Mining Co., Boston, Mass. AMIDON, RICHARD G., Min. Engr 3659 Girard Ave. N., Minneapolis, Minn. ANDERSON, HECTOR G. S., Min. Engr 323 N. 13th St., Muskogee, Okla. ANDERSON, JOHN CARTER, Petroleum Engr 2307 S. 33d St., Omaha, Neb. CLARKE, ALEXANDER FIELDER, Works Mgr., Firth-Sterling Steel Co., McKeesport, Pa. CROSS, CARLOS GARCIA, Min. Engr Calle Valparaiso 194, Vina del Mar, Chile. DAWSON, THOMAS WILLIAM, Min. Engr., Asst. Chief Engr., H. C. Frick Coke Co., Scottdale, Pa.

Jan 3, 1915

[Year of Election to Honorary Membership 1876. PROF. RICHARD AKERMAN Stockholm, Sweden. 1913. DR. FRANK DAWSON ADAMS Montreal, Canada. 1920. HENRY STURGIS DRINKER Bethlehem, Pa. 1888. PROF. HATON DE LA GOUPILLIERE Paris, France. 1906. SIR ROBERT A. HADFIELD London, England. 1917. HERBERT HOOVER Stanford University, Cal. 1919. ROBERT W. HUNT Chicago, 111. 1915. JAMES FURMAN KEMP New York, N. Y. 1905. PROF. HENRI Louis LE CHATELIER Paris, France. 1913. EZEQUIEL ORDOENEZ Mexico City, Mexico. 1909. ALEXANDRE POURCEL Paris, France. 1911. ROBERT H. RICHARDS Boston, Mass. 1906. JOHN E. STEAD Middlesbrough, England. 1902. PROF. DIMITRY CONSTANTIN TSCHERNOFF Petrograd, Russia. 1907. CHARLES D. WALCOTT Washington, D. C.] [ ]

Jan 1, 1925

[Year or HONORARY MEMBERS Election 1876. PROF. RICHARD AKERMAN Stockholm, Sweden. 1913. DR. FRANK DAWSON ADAMS Montreal,. Canada. 1888. PROF. HATON DE LA GOUPILLIERE Paris, France. 1906. SIR ROBERT A. HADFIELD London, England. 1896. HERBERT HOOVER Stanford University, Cal. 1874. ROBERT W. HUNT Chicago, Ill. 1915. JAMES FURMAN KEMP New York, N. Y. 1905. PROF. HENRI Louis LE CHATELIER Paris, France. 1918. EZEQUIEL OBDONEZ Mexico City, Mexico. 1909. ALEXANDRE POUBCEL Paris, France. 1911.. PROF. ROBERT H. RICHARDS Boston, Mass. . 1906. JOHN E. STEAD Middlesbrough, England. 1902. PROF. DIMITRY CONSTANTIN TSCHERNOFF Petrograd, Russia. 1910. PROF. TSUNASHIRO WADA Tokyo, Japan. 1907. CHARLES D. WALCOTT Washington, D. C.] [ ]

Jan 1, 1925

Adams . Bernard . Student. South Dakota School of Mines .Rapid City . S . D . Ahlskog . Harold A. Student. Washington State College Pullman. Wash . Aldridge. John. Student. New Mexico School of Mines Socorro. N . M . Almstrom . Adne A .. Student. Met . Engrs.. Washington State College ..... .Pullman. Wash . Ancell . Virgil F.. Student. Missouri School of Mines Rolla. Mo . AnkudinoE. N., Mill Draftsman. Arthur G . McKee & Ch., 2422 Euclid Ave., Cleveland. Ohio . Avablaea . Salvador C.. Student. Univ. of California Los Angeles. Cal. Armstrong. Robert E .. Student. Lafayette College .Easton. P a Armstrong . Thomas E.. Student. Univ . of California Los Angela. Cal Aud. Robert A .. Student. Lafayette College Easton. Pa .

Jan 1, 1929

Albert Ladd Colby, New York, N. Y. (communication to the Secretary†):—I observed (Trans., xxxvii., 585) that to obtain tenders from several American mills, the foreign engineer should modify his maximum phosphorus to 0.10 per cent., not as Mr. E. Windsor Richards quotes me, that no American rail-maker can produce rails under 0.10 per cent. of phosphorus. Mr. Richards claims that no English engineer would agree to accept 0.10 per cent. of phosphorus on any terms whatever. Mr. Webster writes that only after an engineer has .been convinced that rails can be made in America equal in every respect to those he is getting abroad, should he be asked to modify ally conditions in his specifications. I know it to be a fact that during recent years in many cases, as, for instance, When delivery could be secured more promptly in the United States than in Europe, the consulting engineers of several British and colonial railroads have frequently agreed to modify their phosphorus requirement to a maximum of 0.10 per cent., and the rails delivered' under these modified specifications have, under like conditions, given just as satisfactory service and proved to be no more brittle than similar sections of 0.07 per cent. phosphorus rails, rolled in England under the same specification except without modification as to phosphorus. Furthermore, it would appear from the analyses of British rails, quoted by E. A. Dancaster,2 in his discussion of Mr.

Jan 1, 1908

By W. E. C. Eustis

1st. THE fine iron ore is mixed with a sufficient proportion of fine coking coal, and is coked in any of the ordinary methods for making coke. The effect of this is to convert the iron oxide into sponge in such a shape that the usual trouble of oxidation is avoided. 2d. The resulting mixture of coke and sponge is melted down in an ordinary cupola, the coke furnishing more than sufficient fuel for that purpose. I may briefly point out here that in the first place the iron is sponged, and this sponge, as is well known, contain-, no phosphorus or silicon when the reduction takes place at a low temperature; and in the second place this sponge is melted down in a cupola in which there is no zone of reduction for phosphorus or silicon, and that con¬sequently the resulting iron should be free from both of these impu¬rities. 3d. The liquid sponge, now carburized, is run into an open-hearth furnace, where the requisite degree of hardness or softness is obtained by adding some of the fine ore, and the usual dose of ferronmanganose. I have merely given above the rough outlines of the process, but it is my intention, as early as possible, to bring the process more fully before the Institute.

Jan 1, 1881

By Sheldon P. Wimpfen

EVER since the Phoenicians roamed the known world in quest of metals to harden their helmets and precious metals and gems to adorn their ladies, many other nations have sought metals in the far corners of the earth. During the past 75 years American engineers have been among the foremost in seeking for and developing ore deposits. They have been responsible for many of the principal discoveries and for the application of modern methods to mines in the far comers of the earth. American mining engineers with a zest for travel and an insatiable appetite for metals have also introduced throughout the world many articles made of metal which we consider essential to everyday life. Production and consumption of these metals in many foreign countries has brought to these countries an increased standard of living and added tax revenue to their governments. But unfortunately engineers from this country are no longer given ready access to all the countries of the world. This is not only unfortunate for American engineers but also for the countries that have adopted the exclusion policies and especially so since time has proved that in countries where the American engineers have gradually been excluded there has been a significant decline in the progress of the mining industry. Removal of these barriers to professional men would aid immensely in the world-wide development of the mineral industries. New areas brought into production under the guidance of American engineers with their exceptional know-how would provide more jobs for nationals of the countries involved and a better standard of living for the nations as a whole.

Jan 1, 1946

By Rudolf Gahl

SOME time ago the Detroit Copper Mining Co. had to decide the question whether it would pay to re-treat slime-tailings, and several machines were tested in order to ascertain the type of construction which would give the greatest saving. In previous tests on the ore of this company, several tables proved far inferior to the Frue vanner, and for this reason they did not receive any serious consideration. In the late tests, however, one table was found to surpass the vanner in the percentage of saving made. The Frue vanner used in these tests had been adjusted approximately to the slope which the slime-vanuers in the concentrator of the Detroit Copper Co. had at that time, about 2 in. between the inside of the wooden posts, or 0.272 in. per ft. It had not been determined, however, if this slope was the most economical one for treating the slime-feed in the mill, or for re-treating the tailings from the slime-vanners, and I was instructed to ascertain by test-runs, under different conditions, the best adjustments for the work to. be done. In order to determine if a change in the adjustments of the machines would improve the results, it seemed sufficient to continue running the tests between the vanner and the table before mentioned, keeping the feed and all other conditions the same, but. varying the adjustments of the vanner .from run to run. I employed a vanner-man of long experience to operate these machines, who expressed the opinion that a slope between 2 3/8 and 2.5 in. between the posts (0.323 and 0.340 in. per ft.) would give the best results. Some runs made this way gave a considerable improvement. While for a slope of 2 in. (0.272 in. per ft.) the saving had been only 40.5 per cent. of that of the table, it .was 49.2 per cent. for 2.5 in. (0.340 in. per ft.) slope. A decrease of

Sep 1, 1909

By R. W. Raymond

ALL history testifies that the mineral resources of a region have furnished both the impulse for its first development by man, and the foundation for its subsequent occupation by civilized and prosperous communities. In the pre-historic ages, the hunters, fishers, shepherds and gardeners of the world may have wandered or tarried without regard to the attractions of the mineral deposits which they could not utilize, and therefore did not value. But with the rise of civilization, as expressed in manufactures and commerce, the national value of such deposits began to be realized. Barbarous and remote tribes, possessing the sources of such supplies, won recognition in trade long before they could attain it through any other means. Thus, the North American Indians of Lake Superior exchanged their native copper for the mica of North Carolina; the ships of Tyre sailed all the way to Spain for lead and to Britain for tin; and the fleets of Solomon brought gold from Tarshish. In more modern times it has been chiefly the precious metals that have stimulated exploration and conquest. The inherent qualities and the traditional value of gold and silver sufficiently explain this historic fact, the continued existence and potency of which is evidenced, even in our own times, by the occasional rush of eager adventurers to new districts where gold and silver have been discovered. The history of North and South America has been peculiarly influenced by this factor. It was the prospect of obtaining gold and silver that led the Spanish adventurers to the shores of America, and the conquests of Mexico by Cortez and of Peru by Pizarro were inspired by the stories of the wealth of the Aztecs and the

Mar 1, 1909

By C. J. Bechtoldt, H. C. Vacher

Quenched alloys, prepared by powder metallurgical techniques, were examined by microscopic and X-ray diffraction methods. The compositions and heat treatments were chosen so that the chromium and nickel solvuses could be determined and a range of composition and temperature, in which a eutectoid had been reported, could be explored in small intervals. The results showed no evidence of eutectoid reactions having taken place. ALLOYS containing iron, chromium, molybdenum, and nickel are extensively used in high-temperature applications. In order to provide basic information on the solid-state reactions that occur in such alloys, the National Bureau of Standards is engaged in an extensive study of the equilibrium phases in the binary, ternary, and quaternary systems involving these four metals. Attention was directed to the chromium-nickel system because a review of the literature showed conflicting data. A recent compendium1 of the constitution of binary alloys gives two diagrams for the chromium-nickel system, one a simple eutectic and the second a diagram showing a eutectoid and a eutectic. The eutectoid was the result of an allotropic transformation in a high-temperature solid-solution form of a chromium-rich phase called 0. The approximate temperature and composition of the eutectoid was 1200°C and 30 at. pct Ni. In the preliminary study, at the Bureau, no transformation was indicated in the chromium-rich phase of ternary and quaternary alloys in which chromium and nickel were major components. Similar results have been reported from time to time in the literature,2-8 In consequence of this situation, a systematic study was made of the constitution of heat-treated chromium-nickel alloys using metallographic and X-ray diffraction methods. The compositions of the alloys were selected so as to determine the boundaries of the chromium-rich and the nickel-rich phases and to explore in small intervals the ranges in composition and temperature in which the eutectoid had been reported. The results of this study are reported and discussed in the present paper. EXPERIMENTAL PROCEDURES Materials, Alloys, and Heat Treatments—The alloys were prepared by a powder metallurgy technique similar to that used in earlier work.9 Analyses of the materials used are given in Table I. Powders were mixed using a vibrator in 30-g batches of predetermined composition; 2-g pellets were made from the mixture by compacting at room temperature in a 1/2-in. diam mold under 60,000 lb per sq in. pressure. The pellets were sintered in dry hydrogen for 10 days at 1300°C. At the end of the sintering treatment the specimens were quenched in water, which caused a pale green film to form on the chromium-rich alloys and thin black scale to form on the nickel-rich alloys. The pellets after sintering were approximately 1/2 in. diam by 3/32 in. thick. The purification train9 was modified by inserting a tube of titanium turnings, heated at 700°C to increase the efficiency of the removal of oxgen and nitrogen. It was found in the earlier work that the sintering treatment lowered the carbon, oxygen, and nitrogen contents of chromium-rich alloys to 0.01, 0.01, and 0.004 wt pct, respectively, and that there was a loss of chromium. In order to ascertain the extent of this loss, the chromium contents of certain alloys were determined chemically. They included those alloys used to determine the parameter-composition curves and those of critical composition, used to determine the chromium-solvus microscopically; these analyses were made on samples after the final heat treatments. The mixed powder values for the chromium content of those alloys that were not analyzed were adjusted to conform to a smooth curve based on the chemically analyzed values for

Jan 1, 1962

By J. T. Norton

As cold working is an important feature in a great many of the fabricating processes now applied, this paper presents some ideas of the nature and results of the plastic deformation produced in this operation. The art of manufacturing metal for practical uses is very old and has undergone very great development. The science of metals has also developed very rapidly recently and the various processes to which ,metals are submitted are much better understood now than they were even a short time ago. All the knowledge that can be obtained on this subject is useful because it promotes efficiency in converting metal into finished articles. ATOMIC ARRANGEMENT IN CRYSTALS In the solid state all metals are crystalline. The atoms are arranged in, a definite symmetrical configuration, which is repeated at regular intervals, and thereby defines what we may term a lattice. Presumably . the atoms exist as positive ions. The dissociated electrons place themselves between groups of positive ions, and thus define a second lattice, an "electron lattice." From such a point of view, the crystalline forces which hold a metal together are the electrostatic attractions between positive ions and negative electrons. The particular type of lattice into which a metal crystallizes depends on the number of these lattice electrons given up by each atom, and is thus connected very closely with the chemical valence of the metal.

Jan 12, 1926