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By E. P. Mathewson

THE OLD Pueblo smelter is being dismantled after 43 years of continuous operation, from 1878 to 1921. It was built by Mather and Geist, on a bluff overlooking the Arkansas River just below the, city of Pueblo. At the time of its construction Pueblo was considered a most favorably situated town for a custom smelter. Coal, coke, fuel, limestone, iron ore, lead, silver, and, gold ores were plentiful. It was a "downhill pull" from all directions to Pueblo. Labor, both common and skilled, was plentiful and efficient. Leadville was in bonanza and there were not sufficient furnaces in Colorado to handle the ore offered. The plant prospered from the start. It soon required more capital; so the owners; with the assistance of Thomas Nickerson of Boston, at that time prominent in the affairs of the A., T. & S. F. railway, formed the Pueblo Smelting & Refining Co. About this time, also, very heavy shipments of rich silver ore from New Mexico began to come in. Agencies were established for the purchase of ores in the most important mining camps in the country from Kingman, Ariz., to Butte, Mont. Highly siliceous silver-bearing ores from Butte were shipped to Pueblo in train loads. This was used chiefly in the concentration of leady mattes. RECOLLECTIONS OF MR. GEIST, FOUNDER OF PLANT Mr. Geist is living in Guadalajara and has sent the following brief letter: "Early in 1878 the firm of Mather & Geist, which had been operating in Utah and had then closed their smelter there, after diligent search for a new location selected Pueblo. We erected the first smelter in the valley, blowing in the first furnace in 1878. Mather & Geist carried on until January, 1882, when they transferred all their business to the Pueblo Smelting & Refining Co., which had been organized in December, 1881. Full details of this transfer are given in the enclosed Report, which was issued early in 1882, for the purpose of interesting more capital, in which we succeeded admirably. "I personally did all the work of manager and super-intendent, some job in these days. My technical quali-fications were that I was a member of the class of 1866, Yale Sheffield Scientific. I was born in 1848, so was the youngest member of the class.

Jan 11, 1923

By H. C. Heard

The review by Professor J. C. Jaeger (Chapter 1) briefly summarizes and discusses a select group of papers by various workers dealing primarily with aspects of fracture in brittle rock materials. Professor Jaeger's treatment is primarily concerned with the correlation of phenomenological and theoretical failure criteria with empirical results from short duration tests at ambient temperatures and generally at low lithostatic and interstitial fluid pressures. As engineering rock mechanics becomes more concerned with new techniques of mineral exploration and production at increasingly greater depths in the crust, it is well to be aware of the effect of the environment -that of the superposed stress field upon the lithostatic and interstitial fluid pressure, the temperature and the duration of the loading upon the failure of rocks either by fracture or flow. All results to be discussed here are from laboratory tests on small homogeneous samples, thus caution should be used in the direct extrapolation of these results to large inhomogeneous rock masses having quite different boundary conditions in the earth. The purpose of this supplement is to briefly point out the major effects of these parameters as examined singly, with all others held constant, and to cite some recent results which apply to the main theme on the brittle failure of rocks. The total stress field imposed upon a small volume of porous and permeable rock in the earth's crust may be thought of as the sum of an applied differential stress, plus a lithostatic pressure, plus an interstitial fluid pressure. The differential stress portion may be completely specified by nine components, six shear and three normal. If the small volume element is in rotational equilibrium, by suitably choosing our coordinate axes we may resolve these nine components into the three principal com-

Jan 1, 1967

By C. A. Zapffe, C.E. Sims

Many hundreds of publications have appeared during the past 78 years that treat the subject of hydrogen in iron and steel.l05 but conclusions regarding the functions of hydrogen in causing some important defects in steel are still unsatisfactory to many; and other hydrogen-caused phenomena yet remain to be identified with this gas. The most widely discussed of these defects is hydrogen embrittlement, but the conception, perhaps the popular one, that embrittlelnent is due to hydride formation aoes not conform to the known facts.l04 The true identity of hydrogen embrittlement seems instead to lie in a mosaic nature of metal crystals, which is a concept not Yet accepted by most metallurgists. A study of hydrogen embrittlement therefore provides new viewpoints in regard to the crystalline substructure of steel.

Jan 1, 1941

By C. E. Sims, C. A. Zapffe

Many hundreds of publications have appeared during the past 78 years that treat the subject of hydrogen in iron and steel.l05 but conclusions regarding the functions of hydrogen in causing some important defects in steel are still unsatisfactory to many; and other hydrogen-caused phenomena yet remain to be identified with this gas. The most widely discussed of these defects is hydrogen embrittlement, but the conception, perhaps the popular one, that embrittlelnent is due to hydride formation aoes not conform to the known facts.l04 The true identity of hydrogen embrittlement seems instead to lie in a mosaic nature of metal crystals, which is a concept not Yet accepted by most metallurgists. A study of hydrogen embrittlement therefore provides new viewpoints in regard to the crystalline substructure of steel.

Jan 1, 1941

By William Cruger

OUTLINE SUMMARY A. Brief Description B. Characteristics 1. Can be highly cost effective 2. Restricted in usage 3. Political Controversy 4. Volume of Transactions 5. Users C. Mechanism 1. Five steps D. Investor issues 1. Application 2. Restricted usage 3. Discount 4. Formal or informal process 5. Restricted benefits 6. Recompense 7. Window of opportunity THE VARIOUS PROGRAMS1 A. Brazil B. Chile C. Venezuela D. Argentina E. Mexico USAGE IN THE MINING, METALLURGICAL, AND PETROLEUM INDUSTRIES

Jan 1, 1990

By John V. Beall

During the last quarter of 1948, two new machines, which may revolutionize the coal mining industry, made their first public appearance within two months of each other. Both are designed to mine and load coal continuously. On Oct. 27, the "Colmol," invented by C. H. Snyder and A. E. Lamm, president and executive vice-president, respectively, of the Sunnyhill Coal Co., was demonstrated at the No. 8 mine of that Company at New Lexington, Ohio. The "Joy Continuous Miner," invented by H. F. Silver, president of the Silver Engineering Works, Denver, and developed and manufactured by the Joy Manufacturing Co., was demonstrated at the Mathies mine, near Finleyville, Pa., in the Pittsburgh coal seam.

Jan 1, 1949

By Robert H. Richards

This is in part a review paper, indicating the various steps that have been taken in developing hindered-settling apparatus, some of the standard data that have been obtained, and some of the conclusions one is led to as to the effect of it in improving concentrating-methods and machinery, and in part it brings in some unpublished work. Causes oF Loss in ORe-ConcEntration. In making a study of the separation of valuable minerals from the waste gangue, particularly by water concentrators, it is necessary to define, first of all, what are the causes of loss that are likely to interfere with the concentration. Having made this definition, we can then study to see in what may the machines make their losses, and plan remedies for them in an intelligent way. Losses may be stated to occur as included grains, as flat or long grains, as fine free mineral, and as absolute slime. We will take these up one by one, as follows: Included Grains.—Fig. 1 shows by a set of diagrams how included grains may occur : first, where the heavy mineral grains attached to the quartz are of large size; secondly, where they are of small size; and thirdly, where very fine particles of heavy mineral are included in the quartz. We have to decide in regard to included grains whether they are rich enough to go direct to the furnace, or poor enough to throw away, or whether they lie between these two points and require recrush-ing as the only means of severing the values from the waste. This last case is the orlly one requiring special treatment at our hands. We will therefore consider that next.

Jan 1, 1911

By Ganesh P. Mohanty, James J. Wert

THE brittleness of the intermetallics usually render their deformation studies at ordinary temperatures using conventional techniques inadequate. On the other hand, although X-ray line broadening measurements is not a complementary technique, it provides a means for gaining limited but useful information on the cold worked state of these materials. In the present instance, a study of the effects of cold work in the lead telluride intermetallic compound was carried out by analyzing the diffraction profiles of the deformed and the corresponding annealed samples. An ingot of PbTe was prepared by induction melting high-purity lead and tellurium in a quartz crucible under an atmosphere of argon. After homo-genization, the ingot was ground to -325 mesh at room temperature, and using a polished die the cold- worked powder was pressed into the form of flat faced briquets for diffraction measurements. A spectrometer with 0.125 deg per min scanning velocity, CuKa radiation, pulse height analyzer, and a proportional counter were employed in the X-ray measurements, and the powder peaks were collected from the sample in fully cold-worked state and after it had been annealed to relieve the effects of cold work completely. For reliable estimates of the peak extremities, small angular ranges where the tails merged into the background were point counted. Fourier inversions of the experimental peaks were carried out in an IBM 705 computer using the procedures introduced by stokes.' Both the cosine and sine components of the Fourier series were used to take into account any peak assymetry arising

Jan 1, 1963

By J. A. Grimes, Paul Billingsley

A. Introduction. 1. Association of Ores and Igneous Rocks. 2. Identity of Granite Rocks. B. General Geology. 1. Geologic Events of the Igneous Cycle. 2. Association of Igneous Intrusions with Tectonic Forces. C. Igneous Rocks. 1. Andesite Period. 2. Granite Period. (a) Diorite. (b) Quartz-Monzonite. (c) Aplite. (d) Quartz-Porphyry. (c) Quartz-Veins. 3. Rhyolite Period. 4. Comparative Analyses. D. Classification of Deposits. 1. Genetic Classification. 2. Parallelism Between Igneous Stages and Stages of Ore Deposition. Part 2.—The Ore Deposits Andesite Period. A. Andesite Phase. 1. Disseminations—Baggs Creek. 2. Contact Deposits—Iron Mines of Ekhorn Mountains. 3. Fissure Veins—Emery District. (a) Fissure Veins in Andesite Walls. (b) Mineralization Along Bedding of Flows. (c) Mineralization of Amygdaloidal Lavas. (d) Mineralization of Breccia. 4. Summary.

Jan 1, 1918

By M. H. Richman, W. D. Sproul

THE indexing of a field-ion micrograph is in many cases similar to the indexing of the poles of a stereo-graphic projection.* If one has a standard projection as a guide, the task of indexing is relatively simple. In this way, field-ion micrographs of bcc and fcc wires have been oriented from projections available in most any text on X-ray diffraction. These books always illustrate the projections for the bcc and fcc structures and even for a particular hcp structure. There is no "standard" hcp projection because the angles between planes depend on the c/o ratio of the unit cell. In order to index field-ion micrographs of hcp metals, one must compute the angles between various planes—a rather laborious task. In recent work,, we have had to identify the structure and index the orientation of field-ion micrographs of the compounds WC and W,C. To overcome the problem of computing angles by hand or calculator, a program was written in Fortran lV for use on the IBM 360, Model 50 which will compute all angles between planeswith indices (hlklll) and (17,k,l2) in the range from (447) to (444) for any given c/o ratio. The program, which is more specific than that of Camp and clum, was so written as to take advantage of the multiplicity of the hexagonal system, and, for the limits defined above, only 26,649 values out of a possible 265,721 values had to be computed. This is a 90 pct saving in time (and cost) and was accomplished in the following way. Because the lattice parameters of the hexagonal crystal system are defined such that: a = b * c [1] the I index does not enter into the multiplicity (i.e., it cannot be transposed with the h or k indices), and all possible values of h and I, from 4 to 4 must be used—a total of eighty-one combinations. The index h2 varies the most—it must assume values from - Ill,: to 3Ihl. The indices kl and k2 are always equal and vary

Jan 1, 1969

[Aase, Qlenn D., (Junior Member '40) Jr. Met.. American Smelt. & Refin. Co., Selby. Calif. Abadie, Henry G., (Junior Member '43) Petr. Engr.. Avenal, Calif. Abbott, Clarence E., (Member '04) Civil En=.. V.P.. Tennessee Coal. Iron & R.R. Co., 1542 Brown biarx Bldg.. Birminpham, Aln. Abbott. Fred E., Jr., (Member '44) Petr. Engr., C/O Arabian Anierican Oil Co.. A.P.O. 816. c/o Postmaster, New York, N. Y. Abel, Raymond L., (Member '28) Chem. Engr.. C. O., Pittsburgh Chem. Warfare Procurenlent Dist.. American Bank Bldg., Pittsburph. Pa. Abel, Walter D., (Member '32) Min. Engr.. Supvr. Engr.. RFC, Los Angeles, Calif.]

Jan 1, 1946

By M. K. Foster

Ten horizontal retort zinc blocks of a modified Hegeler design are in operation at Nueva Rosita, Coahuila, Mexico, and produce approximately 170 t of spelter daily, or 62 000 t/year. A block consists of two furnaces of 448 retorts each, making 8960 retorts as the plant complement. Each furnace block is fired with natural gas and air maintaining the combustion mixture in the furnace always slightly reducing. No attempt to recover energy through waste heat boilers is made. The spelter moves to market by rail and truck either in palletized bundles weighing approximately 1060 kg, as loose slabs weighing 26.5 kg each, or as 1088 kg ingots. At present 46% of the metal is exported and 54% is consumed domestically in Mexico. The present day trend toward equalized or alloyed spelter, as well as special shaped castings results in sales of 35% of the entire plant's production. Sulfuric acid is also produced by the Contact Process using vanadium pentoxide as the catalyst. The plant is basically a Monsanto contact system, producing approximately 68 t of 100% sulfuric acid daily. Both 98.5% sulfuric acid and 20% oleum are available. All of the acid made is consumed in Mexico. Shipments are made in 26,900 dm3 tank cars.

Jan 1, 1970

By Walter Crafts

KEYNOTE of the technical sessions of the Iron and Steel Division at the Annual Meeting was struck by Leo F. Reinartz in his Howe Memorial Lecture on "The Development of Research and Quality Control in a Modern Steel Mill." In describing recent developments in steel-producing practices at the American Rolling Mill Co. the co-ordination of practical observation and directed research with operations was stressed and was shown to have resulted in economical production of steels of uniformly high quality. Empirical methods based on inaccurate and incomplete experience resulted in the production of commercial products of variable quality and were recognized as inadequate; a research program was therefore initiated that has been justified by its fruits. To name a few outstanding achievements such as Armco iron, steel for electrical sheets, wide continuous strip of superior surface and quality, and non-aging steel is not sufficient to summarize the results of this increasing effort toward better steel products. In addition to the development of new products the faithful observation of operating procedures, the co-ordination of the resulting information, and the standardization of processes have made the steel of today much more uniform and thus more economical and useful to the nation.

Jan 1, 1943

By F. E. Harris

IT has been said that carbon is "ubiquitous" with reference to iron alloys. Certainly at temperatures where carbon and iron form the solid solution, austenite, it may be readily added to, or removed from, steel surfaces. Differences in concentration potential are the sole requirements for carbon flow. To measure the rate of carbon flow, a proportionality factor, D, is arbitrarily expressed in units of (length)2 X (time)-1. If the term used for carbon concentration is weight pct C, as is customary, then a factor must be found, changing this term to one of weight per unit volume when the diffusion coefficient, D, is used in flow formulae. The determination of D values for carbon is complicated since D varies with the concentration itself. The Matano method has often been employed for systems involving a variant D. This method expreses an evaluation of unsteady flow whereby .0 is given a relationship with the numerical value of C-X slopes. The author contends that this solution is incorrect, except when D is invariant. The primary purpose of this paper is to support this contention. Here diffusion is controlled under two conditions of flow. The first part deals with the steady state; the second part considers unsteady flow under definite restrictions. Beginning with the fundamental concept, the development is continued until equations for C-X curves are obtained. The solution is then subjected to experimental data. It is realized that a great amount of reliable data is required for a rigorous proof. No such research is claimed. Instead an attempt is made to set forth the physical significance of the diffusion mechanism, and particularly to express the factors which influence the flow of carbon in austenite. Of equal significance is the implication that gaseous media may be employed with reasonable accuracy in making these determinations. THE STEADY STATE DIFFUSION OF CARBON IN AUSTENITE The fundamental experiment defining diffusion in solid metals may be readily performed for carbon in gamma iron.1 For this experiment a thin plate of medium carbon steel is chosen. The surfaces of this plate may be taken as two parallel planes which may be considered infinite for points well in the center of the planes. These two planes are held at different concentrations of carbon at a constant temperature. This temperature, 1700°F for example, is one where the single phase, carbon in solution with gamma iron, exists. When these conditions are held for a sufficient time the concentration of carbon of the different points of the solid settles down towards its steady state value. At points well removed from the ends, the concentration will remain the same along planes parallel to the surfaces of the plate.

Jan 1, 1947

By G. W. Brock

Experiments in the form of aging of overstrained tension specimens and elevated temperature tension testing, have been carried out on recrystallized arc-cast molybdenum. The aging behavior of molybdenum was found to be strongly dependent on the degree of plastic strain present in the lattice: the reason for this being the low solid solubility for the common interstitial elements in molybdenum. GEORGE W. BROCK, formerly Research Associate, Department of Theoretical and Applied Mechanics, University of Illinois, Urbana, III., is Research Associate, Department of Engineering Sciences, IBM Research Center, Yorktown Heights, N. Y. Manuscript submitted January 19, 1961. IMD THE term strain aging is familiar in connection with the recovery of the yield point in mild steel after tensile overstraining, and there are other instances where it is known to exert an appreciable effect on mechanical properties. For example, steel exhibits a greater tensile strength at mildly elevated temperatures than at room temperature and serrated stress-strain flow curves occur under certain conditions. It has been known for a number of years that the phenomenon of strain aging is directly connected with the presence of carbon and nitrogen in the lattice; and extremely small amounts of either element are sufficient to produce the effect. In this study, the aging behavior of overstrained tensile specimens of recrystallized molybdenum has

Jan 1, 1962

By Charles W. Perry

The options of enhanced oil recovery, coal syncrude, and shale syncrude are compared by approximately equivalent economics. The physical constraints for the major enhanced oil recovery processes are described, followed by new estimates of cost. The range for all three options in terms of light syncrude equivalent are $22 to $40 per barrel in 1980 dollars.

Jan 1, 1982

By Kenneth S. Ritchie

THE discovery well of the world's -deepest oil producing structure, University 1-B of Group No. One Oil Corporation, in the Big Lake oil field, Reagan County, Texas, has had a remarkable record. The well is outstanding for the following reasons: (1) It is the world's pioneer well to produce. oil in commercial quantities from a structure 8500 ft. below the earth's . surface; (2) this well was the only. producer from the 8500-ft. pay for a period of 17 months and 24 days; (3) the flow of the discovery well has been free from-the customary changes at the casinghead, with the exception of putting on a back-pressure of 185 lb.; and, (4) the well's daily production of oil and gas increased rather steadily for 17 months and 18 days from an initial of 40 bbl. per day to a maximum of 2926 bbl. per day, and then six months later, after a period of decline and self-readjustment to subsurface changes caused by six more deep producers, the well set its real record for one day's production of oil at 2950 bbl

Jan 1, 1931

By D. L. Albright, R. W. Kraft

Solidification experiments were conducted with the objective of testing the theory of eutectic colony formation. Appropriate control of variables in tests on a series of high-purity aluminum-copper specimens of eutectic composition resulted in the observation of three types of eutectic microstructures, these being a unique structure consisting of lamellae essentially parallel to one another, a banded structure, and the colony structure. Lamellar faults, which are morphologically similar in many respects to edge dislocation models in crystals, produced a complex substructure in these specimens. SOLUTE rejection at the advancing solid-liquid interface of a unidirectionally solidified single-phase metal can cause the liquid immediately in front of the interface to become constitutionally super-cooled below the equilibrium liquidus temperature. Constitutional super-cooling occurs if the solidification rate, R, is too rapid, or if the thermal gradient in the liquid at the interface, G, is too low. 1 This constitutionally supercooled layer in turn stabilizes a cellular rather than a planar interface.&apos; A similar cellular interface has been observed when lamellar and other types of eutectics were unidirectionally solidified, and it has been shown that the cellular interface led to the formation of eutectic colonies.&apos; The lamellar structure is fan-shaped at the edges of colonies (which correspond to valleys or grooves in the cellular interface) because the lamellae grow normal to the local interface. One of the possible mechanisms which might cause the formation of the cellular interface, in the case of solidifying eutectic alloys, is constitutional supercooling of the liquid with respect to a third component rejected by both phases of the eutectic.3,4 On the basis of the analogy between the solidification of single-phase metals and binary eutectics, a eutectic alloy should solidify with a planar interface if the ratio of G/R is sufficiently high to compensate for any impurity which might be present and causing constitutional supercooling. The fan-like microstruc-ture of eutectic colonies should not occur under these conditions and the lamellae should be parallel to one another and to the solidification direction for extended distances. The experiments conducted in this investigation were designed to test these ideas. Following a resume of the experimental procedure, the various microstructures observed during the study are described, and their relationship to the growth conditions which produced them is discussed. EXPERIMENTAL PROCEDURE The eutectic between an aluminum solid solution and 0 phase (approximate composition CuA12) was chosen for this work for the following reasons: it was known that a lamellar structure forms, the eutectic temperature is low enough to facilitate experimental work, and the components can be procured commercially in a very pure form. High-purity copper (est. 99.999 pct Cu, obtained from National Research Corp.) and spectrographic aluminum rods, having impurities other than copper estimated to be Zn-15 ppm, Mg-10 ppm, Fe-3 ppm, Na-2 ppm, Cd-1 ppm, and Mn < 1 ppm, were melted in a stabilized zirconia crucible in a vacuum induction furnace at a pressure of 10 pof Hg. The melt was superheated to about 1000°C to assure mixing, cooled to 780°C and cast into an investment mold which yielded sixteen cylindrical specimen blanks 1/2 in. in diam and 5 1/2 in. long. The casting was allowed to solidify under vacuum. This master heat had an analysis of 32.6 wt pct Cu and 67.4 wt pct A1 by difference. The cylindrical specimen blanks were remelted and solidified unidirectionally in an apparatus illustrated schematically in Fig. 1. An RF induction coil heated

Jan 1, 1962

By F. W. Clark

At the present time, when lixiviation versus amalgamation is being so thoroughly discussed by practical men, and published information is so meagre, the following tests, made by students in the mining laboratory of the Massachusetts Institute of Technology, may be of interest to others. The ore experimented upon was obtained from the Sombrerete mines near Zacatecas, Mexico. A careful analysis of the dried sample resulted as follows : Per cent. SiO2,............62.79 S.............13.86 Al2O3............4.39 Fe,............11.26 Zn,............1.57 CaO.............2.91 MgO,........... 0.06 Cu,.............0.12 Pb,.............0.40 Sb and As,..........trace CO2,............2.35 Ag,.............0.16 99.87

Jan 1, 1886