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By W. A. Foster

NINETY years after the Riddle nickel deposit N was discovered in Oregon in 1864, Hanna Coal & Ore Corp. began mining operations. Until 1954 much prospecting and preliminary development work had been done on the property, but no ore had been shipped other than for metallurgical testing. The deposit is being explored by churn drilling and trenching, and a few test shafts have been put down for the purpose of studying the ore in place, determining volume and moisture factors, and gathering bulk samples for pilot plant and smelter tests. In churn drilling, 6-in. casing is driven down 2 or 3 ft behind the drill bit and bottomed at each 5-ft interval. All the sludge for each cased 5-ft interval is dumped through a splitter and one eighth is saved and analyzed. Drillholes are stopped after going through the ore zone and penetrating fresh peridotite in which the nickel content is less than 0.5 pct.

Jan 8, 1957

By S. L. Lopata, E. B. Kula

A variation of yield and tensile strength with direction has been noted in heat-treated 4340 steel which had been warn-worked by rolling in the austenitic condition prior to quenching. Measurements by X-rays showed a preferred orientation of martensite crystals. Various ideal preferred orientations of martensite were calculated by assuming a preferred orientation for austenite and transforming this to martensite by the Kurdjumov -Sachs and Nishiyama relationships. Comparison with the measured preferred orientation showed that the ideal rolling texture for austenite in 4340 steel could be expressed as a (112) [111] texture with a component of (110) [112]. No evidence was found for any fiber axis in the rolling direction, or fop- a (123) [412] texture. The observed martensite pole figures can be adequately accounted for by these ideal austenite textures and by the Kurdjumou-Sachs or Nishiyama transformation relationships between austenite and martensite. ALTHOUGH preferred orientations are found in cold-rolled steel sheet and in many nonferrous metals, they are not generally encountered in wrought, heat-treated high-strength steels, since such steels are generally not cold worked sufficiently to develop a strong texture, and any texture that is present is removed during heat treatment by the phase transformations taking place. This report gives details on a preferred orientation found in warm-rolled and hardened 4340 steel. In a recent study, a special combination heat-treating and working technique was used in which 4340 steel was deformed in the austenitic condition, and before re crystallization of the austenite could occur, quenched to form martensite.' Since the austenite was unrecrystallized, it was cold worked and hence could have contained a preferred orientation which could be transmitted to the martensite on quenching, and this in turn could be manifested as a directionality of mechanical properties. Such a directionality of properties was found as a result of working, and this prompted an X-ray study of the preferred orientation. Literature Survey— Rolling Texture in Face-Cen-tered-Cubic Austenite—M a preferred orientation is found in a rolled and hardened steel, it is first appropriate to consider what texture existed in the austenite as a result of the rolling but prior to the transformation to martensite. The changes taking place as a result of the austenite-martensite transformation are then considered. In view of the instability of austenite in 4340 steel at low temperatures, no direct determination of the austenite texture was made. However, an estimate of the texture for austenite in 4340 steel may be made by considering the textures found for other face-centered-cubic metals. Barrett' has reviewed the rolling textures for many materials. The most common orientation in face-centered-cubic metals has the (110) planes parallel to the rolling plane and the [112] directions parallel to the rolling direction, or (110) [112]. Other orientations found are (112) [111], as well as (100) [001], (110) [001], and others. Beck and his co-workers, using quantitative pole figures, report that (123) [121],3 later corrected to (123) [412],4 better describes the ideal orientation. smallman5 reported that the ideal preferred orientation for high-purity face-centered-cubic metals is (123) [121], but that there is a transition to (110) [112] as solid solution elements are added. The latter texture tends to occur more readily at lower temperatures. This transition between the two textures was explained by differences in the slip characteristics with concentration or temperature. More recently, Jones and Fell6 concluded that the (123) [412] texture for face-centered-cubic metals could equally well be represented by a mixture of (110) [112] and (112) [111] textures, and hence it had no physical reality. From the above results it can be seen that there is no agreement on the "ideal" texture for fcc metals and, hence, no firm basis for assuming a texture for austenite in 4340 steel. Therefore, the orientations (110) [112], (123) [412], and (112) [111] have been considered in the following.* *The (123) [4121 is identical to the (123) [121] rotated 90 deg. Orientation Relationship between Austenite and Martensite—When martensite forms from austenite, certain crystallographic planes of the martensite are parallel to planes in the austenite. This orientation relationship was first determined by Kurdjumov and

Jan 1, 1960

By John T. Thorndyke

MOST important of the naturalcalcium silicates is the meta¬silicate, CaSi03, known as wollastonite, after W. H. Wollaston. A large deposit of this mineral was dis¬covered some seven years ago near Code Siding, Rademacher mining dis¬trict, Kern County, Calif., the deposit being some 7500 ft. long and of an average width of 300 ft. It consists of a series of small domes striking north¬erly and southerly and with a dip of 81 ° to the south. This deposit was opened up by a series of small quarries showing a potential tonnage of 12,000,¬000 tons, allowing of cheap mining and transportation, the Southern Pa¬cific R.R. spur track being one mile north of the workings. Numerous sam¬ples taken from different points on the deposit, tested by Mr. Brinker, of the California Testing Laboratories, Los Angeles, showed an average as fol¬lows: Per Cent Silica (SiO2) 47.12 Lime (CaO) 41.72 Magnesia (MgO) 2.72 Alkalies (R,0) Trace Iron (Fe.,O,) 1.60 whereas the theoretical composition of of wollastonite, as given by William Shirley Bayley, is as follows: Silica 51.75 Lime 45.25 The tonnage and purity of this de¬posit led to investigations into its com¬mercial development. Early work es¬tablished the fact that wollastonite was ideal for the manufacture of a tough, almost unbreakable, glass similar to Pyrex. It also established the fact that wollastonite was particularly adapted for use in the manufacture of mineral wool, towards which further research was then directed. Briefly, the prin¬cipal advantages were the substantially unvarying chemical composition of the naturally occurring mineral and its characteristic of being relatively flexi¬ble and highly resilient when fused into a glass. A mineral wool produced therefrom is thus not only of highly uniform composition and color but is most desirable because of the high mechanical strength and length of the individual fibers constituting the wool. It is well known that mineral wool may be prepared by melting a suitable charge of raw material and then intro¬ducing a stream of a suitable fluid, such as air or steam, into a stream of the molten raw material. By this means the molten material is blown into threads or fibers, which are collected in a suitable chamber similar to a tun¬nel, from which they are removed from time to time or continuously. Com¬mercial manufacture of mineral wool has been carried on for only about 50 years, but volcanoes, specifically Kilauea in the Hawaiian Islands, have

Jan 1, 1936

By P. P. Gregory

Natural petroleum gas occurring in the oil-bearing reservoirs is found to exist either as free gas associated with the oil and/or in solution in the oil. In some virgin fields practically no free gas is encountered under the reservoir conditions of pressure and temperature, although in other fields a considerable section of the "pay" horizon is occupied by free gas. In other words, a given oil field may or may not have a gas cap before the exploitation takes place. However, when the reservoir pressure is reduced to a point below the critical saturation pressure by withdrawals of fluids from the producing formation, the gas dissolved in the oil inevitably begins to come out of solution and becomes free gas. Under the controlled methods of production and drilling, a portion of this gas is produced with the oil to the surface and a portion of it remains within the reservoir to accumulate at higher structural levels toward which it migrates by virtue of its low specific gravity. The rate of growth of a gas cap in a given structure depends primarily upon the rate of decline in the reservoir pressure. If the rate of pressure decline is rapid, the gas cap likewise will grow rapidly. On the other hand, shrinkage in the gas-cap area was noted in some fields in which reservoir pressures wereincreasing. Determination of Gas-oil Contact and Thickness of Gas Cap The gas-oil contact can be conveniently located in the process of drilling a well and by electrical logging. However, very little can be found in the petroleum literature concerning methods of predetermining gas-oil contacts in producing reservoirs. Therefore, the writer feels justified in describing briefly a simple, workable, and inexpensive method of determining gas-oil contacts and outlining the limits of gas-cap areas in a field where such knowledge may be essential for efficient production and development operations. The method involves the determination of the following data: (I) Structural data, such as the depth or elevation of the top' of "pay" horizon; (2) reservoir pressures; (3) tubing and casing pressures at the well head; (4) static oil-pressure gradient; (5) static gas-pressure gradient. These data can be secured with a minimum of expense, inasmuch as the

Jan 1, 1938

By J. Morgan Clements

PETROLEUM has been known in Japan since at least 668 A. D., for a picture shows the presentation, during that year, to the Emperor Tenchi (Tenji) of "burning water" and." burning earth" by his subjects from Echigo Province, which today is the largest producer of petroleum in Japan. The burning water was doubtless petroleum and the burning earth either bituminous shale or oil-soaked earth or rock from near the oil seepages. The early methods of getting the oil were simple and similar to methods used today in Japan and in China. Where the seepages occurred, trenches or shallow wells were dug along the seepages and allowed to fill with oil which was then bailed out; in some cases, they filled with oil and water and overflowed. During the 300 years following 1500 A. D:, the use of petroleum in Echigo Province seems to have increased considerably, as compared with earlier centuries, and records show that in 1818 the depth of the wells had been greatly increased. Doubtless, they passed through the seepages and tapped the shallow oil-bearing strata; probably some of these deeper wells were dug before that time. The real value of petroleum was not recognized until early in the Meiji era, which began in 1868, when the Japanese learned that the kerosene that was being imported was derived from petroleum. Guided solely by information obtained from books, they refined the oil and increased the depth of their wells in order to increase the production. The deepest well, dug by hand, about this time was 894 ft.1 (273 m.) and by 1874 the recorded production reached 3499 barrels. In 1876, Benjamin Smith Lyman prepared geological maps of the Echigo oil field, which were the first. of such geological maps made in Japan, and based on these a more enlightened development of the oil fields began; the. Japanese, however, still dug the wells by hand. Toward the end of the '80s, an American well-drilling outfit was secured, but the efforts to use it failed from lack of experience by the operators. In 1888, a complete well-drilling outfit was, purchased and American oil-well

Jan 7, 1922

By Herbert Banks Johnson

DURING the past 10 or 12 years very little information has been made generally available concerning the commercial possibilities of separating materials by means of static electricity; and yet during that same period important improvements have been made in various branches of the science of electricity, which, when taken together, and applied to electrostatic separation, have resulted in important improvements in that art as well. For example, much improvement has been made in high-voltage electrical equipment such as full-wave vacuum-tube rectification and improved mechanical rectification. Great strides have likewise been made in the development of insulators for high-voltage work, not only in the materials used but also in the design of the insulators themselves. Again, in another field, the development of air-conditioning equipment has improved the technique of controlling the surface condition, through drying or humidifying, of the various materials that are passed through the electrostatic separator. In many authoritative publications and textbooks, the electrostatic separation process is declared to require a balance far too sensitive for general commercial application. For example, one publication1 in the past has referred to an unfavorable effect on the process caused by varying atmospheric conditions such as humidity. Some2 have even gone so far as to state that sunlight and shadows may seriously affect the separating efficiency of the process. Such statements may have been true in the early development of the art, when the source of static electricity was derived from a friction disk machine, such as the Wimshurst. The Blake Mosher equipment and the work of Huff in applying motor- generator sets, transformers and mechanical rectification overcame much of this kind of objection to the commercial application of the electrostatic separating process. Another objection made periodically is that it is generally considered necessary to feed the particles into the electrostatic field in a stream that

Jan 1, 1938

By William P. Blake

In another paper I have described in general the close association of zinc-blende and iron pyrites in the ore-deposits of southwest Wis consin. These two minerals generally occur together at the same horizon, a sheet of one being overlain by a sheet of the other; and also the pyrites is disseminated through the blende to such a degree that the latter is rendered comparatively worthless for the produc tion of spelter. Ordinarily the pyrites, which is mostly the trimetric marcasite variety, occurs in about equal quantity with the blende and is separated by hand-culliug and chipping; but there are large de posits where the ores are so closely mixed that they can neither be separated by culling nor by any mechanical method. The specific gravity of the two minerals is so nearly the same that attempts often made to effect even a partial separation by jigging have proved un. successful. The smelters of zinc-ores in the Mississippi valley will not take ores which carry more than 7 per cent. of iron; and it is therefore necessary to cull the massive ('jack" with great care and at consid erable expense, in order to bring it up to the market-standard of purity. The results of trials to effect a separation of blende and pyrites in other regions have been equally unsatisfactory. The literature of this branch of metallurgy abounds in examples. In Wisconsin efforts have been made in the past to " burn " the mixed ores in heaps, in order to soften or destroy the pyrites, and facilitate its separation from the massive blende. The same method has also been resorted to when galenite is mixed through the substance of the blende, for the purpose of disintegrating the ore, so that it could be separated by jigging. The custom was to pile the ore and the fuel together. As might have been expected, the results were far from satisfactory. As is usual in heap-roast ing, some portions of the ore were overheated and decomposed; zinc was lost by volatilization; the galenite in some portions was

Jan 1, 1894

By D. Turnbull, J. H. Hollomon, J. C. Fisher

The concepts of nucleation and of growth have adequately described the isothermal phase transformations to which they have been applied.ls2 However, these concepts have not yet been used successfully to describe the kinetics of a number of transformations that are not observed to take place isothermally. A typical reaction of this type is the austenite to martensite transformation in steels, for which the new phase appears only during cooling of the parent phase. If the cooling is interrupted, transformation ceases; yet had the cooling continued, transformation would also have continued. Nuclei of a new phase do not leap into existence all at once by the simultaneous cooperation of a large number of atoms or molecules of the parent phase; rather they are formed at finite rates by gaining or losing atoms one at a time from the surrounding materiaL3,4 Further thermo-dynamic considerations require a finite concentration of small transitory nuclei of all unstable phases to exist at equilibrium in a stable phase.= For steel in particular, nuclei of ferrite (a iron) exist at equilibrium in austenite (y iron) at temperatures where austenite is the stable phase. If a high-temperature phase a be cooled sufficiently rapidly from temperature TI above the a-ß equilibrium temperature To, to temperature T-1 below To where ß is the stable phase, the equilibrium distribution of ß nuclei corresponding to the high temperature will be retained. There are two limiting possibilities of particular interest: I. The steady state rate of nucleation of ß may be appreciable at T_1, and may require a concentration of sub-critical nuclei exceeding that retained from the high temperature. Time will be required then for the concentration of nuclei to build up to the steady state value, and an induction period will be observed during which the rate of nucleation will increase to the steady state value. 2. The steady state rate of nucleation of ß may be negligible at T-l, while the critical size for continuous growth of ß nuclei, which decreases with increased subcooling of the a phase, may reach a value so small that some. of the retained high-temperature nu-

Jan 1, 1949

By Messervey, J. P.

NOVA SCOTIA is sharing in the rapid advance of the mining industry that is one of the remark- able features of Canada's recent progress. The production of coal and gypsum has increased rapidly, and there has also been a marked development in the mining of gold, salt, zinc, copper and other minerals. Coal, the basis of the principal mining industry in the Province, was discovered by the early explorers on the shore of Cape Breton Island, and used by the garrison at Halifax as early as 1749. The first government record shows total annual sales amounting to 1668 long tons in the year 1785, while last year production was 6,643,000 long tons. The principal mines are discussed in a separate paper by Alexander L. Hay1.

Jan 1, 1928

Jan 1, 1902

By Edmund C. Pechin

I REGRET that I am unable to present this subject in definite form and detail. All I shall attempt at this meeting is to lay before you some curious facts, the bearings and explanations of which must be reserved for future consideration. I hope before the next meeting to have carried experiments far enough to furnish a more important contribution to the science of iron metallurgy. The Wickersham process consists in the introduction into the molten metal, as it runs from the furnace, of air from the hot blast. Mr. Samuel Wickersham is the originator of the plan, as applied in practice, although Mr. Martien had the idea a long time ago, and, I believe, .went to England about it. But at that time Mr. Bessemer was coming before the public with his invention, which engrossed the attention of iron-masters, and Mr. Martien accomplished nothing. The principal difficulty in our experiments at Dunbar was to get a practicable runner or trough, through which the molten metal should pass, and in which it should be exposed to the action of the blast. The runner we used was ten feet long, and perforated on the sides to permit the entrance of the air-currents. When we used a cast-iron and fire-clay runner, the heat was so great that before we were more than half done with a run, the lower part of the runner was melted, and we had a magnificent Fourth of July display of fireworks until the blast was shut off. We had to abandon fire clay. The runner with which we have had the best success ,is made of wrought-iron tubes, 2 1/2 inches in diameter, attached to a wrought-iron frame, and lined with a mixture of crushed conglomerate (quartz) and a little fire clay to give it cohesion. The wrought-iron shell curves inward over the upper edges, so as to catch and throw back into the current the flying sparks and particles of metal thrown out by ebullition. With this we have been able to run 12 to 14 tons at a heat with great ease. Mr. Wickersham has since prepared this material (pounded quartz) into a shaped brick or tile, with the necessary perforations for the passage of the air, which promises to answer every requirement for steady working. As regards the improvement in the quality of the iron, there seems to be no question. A large number of practical tests were made in

Jan 1, 1873

By A. Brown

RAPIDLY rising world demand for mineral pro- ducts has accelerated depletion of the more readily accessible ores, particularly those of premium grade. Operations must proceed at a faster rate to deeper horizons, where there are problems of ground control that restrict economic recovery of the mineral and introduce new hazards to mine personnel. For some of the new Canadian mining fields severe problems of ground stress are still in the future, but much of Canada's mineral output comes from well established mines that have reached considerable depths. It must also be anticipated that the depletion of premium grade ores will eventually necessitate mining low grade material at competitive cost, and unsolved problems of ground control can materially increase costs. Studies of ground stress phenomena in underground workings are therefore considered a present-day necessity, especially since these investigations must be a long-term effort owing to the highly complex nature of the problem and the difficulty of making full-scale observations.

Jan 8, 1958

By Frank A. Hill

A visitor to the Northern anthracite coal-field in 1844 wrote: " History and song have hallowed the valley of Wyoming, and everything pertaining to it seems wrapped in an atmosphere of romance." Song and history have since been almost forgotten in the rush of enterprise and business energy, while the invested capital which has built 160 colliery plants, producing last year 17,031,826 tons of coal and giving employment to 50,000 men and boys, lends an atmosphere the inspiration of which is the very sustenance of prosperity and progress. The fundamental cause of this great valley's financial strength, however, rests on the fulness of its mineral wealth. Its mountains surround and its cities are built upon anthracite coal. Its foundation, physically, financially and socially, is coal. Its geology has governed its growth and developed its greatness. In 1768, ten years, prior to the celebrated Wyoming massacre, two Connecticut Yankees, named Gore, settled near Wilkesbarre, Luzerne County, and, burning Pennsylvania anthracite in their blacksmith's forges, were the first to utilize it as a fuel. Its first use in the household was also at Wilkesbarre, where, in 1808, Judge Fell burned it in an open grate. Carbondale, Wilkesbarre, and Scranton were early recognized as the coal centers of the field.

Jan 1, 1887

By E. R. Shorey

FLOTATION-Mill operator's have recognized that slimes are detri-mental to the flotation concentration of zinc ores. The, presence of primary slime in many of the Wisconsin ores is largely responsible for the failures experienced in treating these ores by flotation. These failures have discouraged the adoption-of the flotation process by opera-tors in the Wisconsin zinc district. The removal of slimes by decantation seemed to be the obvious way to meet the problem of treating slimy or' clayey ores by flotation. To facilitate the removal of slime, it was decided to mix the ore pulp with sodium silicate, which acts to deflocculate the pulp.1 Deflocculation causes slime suspension, making it possible to separate the slime from the sands by decantation.2 Since the literature contains little definite information on the use of sodium silicate to deflocculate ore pulps, a series of tests was conducted to obtain the necessary information. Tests to determine the settling rates of sand and slime in deflocculated pulps were conducted on a dolomite-marcasite-sphalerite ore ground to minus 80 mesh (175 microns) and mixed with water to form a pulp. The deflocculator3 was Mallinckrodt 40° to 42.5° Bé. liquid sodium silicate (Na20 + 3.25Si02). .By microscopic analysis the suspended slimes4 were found to be minus 15 microns (approximately 1000 mesh).

Jan 1, 1934

By F. S. Norcross

DEVELOPMENT of the manganese deposits of Cuba is a matter of importance not only to those involved in this industry on the Island but to the United States steel industry and to our Nation as a whole. For years our domestic resources of manganese have been wholly inadequate, but the recent Cuban development points the way toward solution of this strategic mineral problem.

Jan 1, 1939

By M. C. Leverett

THE dynamic behavior of a multiple fluid system is completely describable in terms of driving forces and resistances to flow. The latter are proportional to the vis-cosity of the fluid under consideration and inversely proportional to a property of the system termed the " effective permeability" to that fluid, a property therefore defined by this relation. Since three phases are usually present in oil reservoirs, it is essential to know the effective permeabilities to the several fluid phases, and the relationship between the composition of the fluid in the pore space and that of the flowing stream, in order to handle satisfactorily certain problems of oil production. In this regard, there are many unknown factors and parameters, and many that can be evaluated only indi-rectly. However, it is expected that work along lines similar to this present under-taking will help materially in solving these problems. Previous workers in this field have inves-tigated the two-phase systems, water-gas,1 water-oil2 in unconsolidated sands, and water-gas3 in consolidated sands. The ex-tension of the study of the flow of hetero-geneous fluid systems from two to three phases involved only slight changes in technique. The apparatus used in the present work, except for slight changes to be described, was that used by Leverett in his water-oil experiments.2 Correlation and interpretation of data were made by methods analogous to those used in two-phase work. The relative permeability to a phase-the effective permeability divided by the permeability of the system to a homogeneous fluid-was employed through-out in correlating the rate of flow of that phase with the composition of the pore space. Quantitative measurements of two inde-pendent physical properties of the system were required to determine the composition of the pore space. As in the two-phase work, the fraction of water was determined electrically. The gas fraction was deter-mined by measuring changes in volume accompanying measured pressure changes. Suitable account was taken of the solubility of the gas in the liquid phases, and of the vapor pressure of the water phase. Since this work was exploratory in nature, no attempt was made to obtain highly accu-rate numerical results. Reasonable precision and reproducibility were sought.

Jan 1, 1940

By NEWTON B. KNOX

PERU, lying south of Ecuador and having common frontiers with Brazil, Chile, and Bolivia, includes over a thousand miles of the Andean mountains. The coastal plain is arid and narrow and the Amazonian jungle region is of interest only on account of its oil and gold placer possibilities. The mountain zone, however, here forms one of the world's most highly mineralized regions. The Peruvian Andes, like their Bolivian and Ecuadorian counterparts, form two distinct chains separated by the great Apurimac and Maralion valleys; but these rivers cut through the Eastern range to join the Amazon drainage, and the central valley is missing north of the passes thus formed by these rivers; the localities where the ranges are joined are aptly called knots. In addition, in central Peru, there exists a third range lying to the east of the first two and separated from them by the Urubamba and Huallaga Rivers. The Eastern range, however, is of little importance to the miner for few metal deposits are to be found therein except for the gold mineralization in the South. In general, deposition of metals in the Peruvian Andes accompanied igneous intrusions which invaded the folded Paleozoic and Mesozoic rocks during the Tertiary; thus the ore bodies are all typical of shallow or moderate depths.

Jan 1, 1945

By Hertha R. Freche

The diffusion of magnesium and silicon from the core into the high-purity coating of Alclad sheet is important commercially, and led to the use of a duplex product for the study of diffusion by means of spectro-graphic analysis of successive layers. It has been found that in the duplex materials the diffusion of magncsium from an undersaturated aluminum-magnesium alloy into its high-purity aluminum coating is approximately of the same order of magnitude as the diffusion of silicon from a saturated aluminum-silicon alloy into its high-purity aluminum coating. However, if magnesium and silicon are both present in the alloy in the ratio of Mg2Si, they appear to diffuse in the approximate ratio of this compound. Finally, if the alloy contains silicon in excess of the amount required by magnesium silicide, the amount of diffused silicon in the high-purity aluminum coating will also be in excess. The interdiffusion of metals in the solid state is of both scientific and technical interest, because it is helpful in the study of the alloy structure and in the solution of problems pertaining to the strength and surface condition of the fabricated product. W. C. Roberts-Austenlt carried out the first quantitative determination of the coefficient of diffusion of gold into lead. This classical experiment was followed by a series of investigations on the diffusion of metals and nonmetals in iron and steel and in nonferrous metals and alloys. Recently the diffusion of copper in coated strong aluminum alloys was investigated by A. Burkhardt2. This appeared to be the first published investigation on the diffusion of metals into aluminum. The present investigation was the direct result of a technical question in connection with alloy fabrication and is a summary of some preliminary work pertaining to the diffusion of magnesium and silicon into aluminum. The results necessarily will be subject to some variations, since this is the first attempt to evaluate the coefficients of diffusion of magnesium and silicon into aluminum according to this method of procedure. This

Jan 1, 1936

By R. C. Thompson

THE lead-zinc mill of Phelps Dodge Corporation, Copper Queen Branch, Mines Division, Bisbee, Arizona, is about 3 miles from the main hoisting shafts of the Junction and Campbell mines at Lowell. All the ore treated in the mill is obtained from these two mines. The mill was designed for an all-flotation treatment of 450 tons of lead-zinc ore per day, and has been operated at that capacity since the start of milling operations on Nov. 17, 1945. An expansion program is underway whereby the mill capacity will be doubled, but this article describes only the original program and presents results of the 45o-ton operation. GENERAL DESCRIPTION The milling plant consists of an ore-receiving bin and three steel-constructed buildings housing, respectively, the primary crushing equipment, the secondary crushing equipment, and the ore-storage bins, grinding, flotation, and filtering equipment. The mill site is the one that was used for a previous copper-concentrating plant, which was operated over a period of years and then dismantled. There remained from this operation some milling equipment, a reservoir for mill-water supply, railroad tracks, tailings-disposal ponds, and a steel-constructed building, all of which were incorporated in the design of the present lead-zinc mill. The location plan of the plant layout is shown in Fig I. The flowsheet of the mill is based on the conventional scheme for lead-zinc treatment, however, several innovations were made necessary in order to utilize the existing building. Placing of equipment also was governed by the design of the building; thus making the mill unique in many respects. The following brief description of the mill building as adapted to the flowsheet points out the compactness of the installation and some of its unusual features. The first floor (Fig 2) houses the grinding equipment, with connecting conveyors for ore feeding, also an air compressor, two vacuum pumps, bins for lead and zinc concentrate storage with individual conveying systems for loading the two kinds of concentrates. Filtering of concentrates is done on the second floor, the concentrates discharging directly into the concentrate-storage bins. On this floor are the lead and zinc filters, two diaphragm pumps, sample-filtering equipment, sample-preparation room and a change room for the mill employees. The flotation machines are on the third floor, at elevations allowing a gravity flow of the lead and zinc concentrates to the thickeners. The annex to the building contains a freight elevator and provides space for all reagent mixing and feeding, also storage of reagents and grinding balls. All the water used for milling purposes is pumped from the Junction mine and

Jan 1, 1947

By A. C. Fraker, H. H. Stadelmaier

WIENER and Bergerl reported the existence of the nitrides Fe3NiN and Fe3PtNwith a cubic L1'2 structure. The present note shows that a similar nitride Fe3PdN can be observed and that the composition range between the iron nitride Fe4N and the nitrides Fe3NiN, Fe3PdN, and Fe3PtN is occupied by single-phase cubic nitrides with structures intermediate between L1' and L1'2. The materials used in this investigation were electrolytic iron of 99.9 pct purity, carbonyl nickel of 99.7 pct purity, sponge platinum of 99.95 pct purity, and palladium sheet of 99.8 pct. purity. Binary alloys of the transition metals were induction-melted in a crucible of fused alumina, powdered, and screened to a particle size of - 200 mesh. The powders were nitrided at 600°C in a gas mixture of ammonia and hydrogen, and the crystal structure was determined with the aid of a Wilson powder camera. The results are compiled in Table I together with information from the paper of Wiener and Berger.1 The compound at the nominal composition Fe3PdN has a diffraction pattern with prominent reflections of a face-centered cubic lattice (h2 + k2+l2 = 3, 4, 8, 11, 12, 16) and weaker superstructure lines (h2 + k2 + 12 = 1, 2, 5, 6, 9, 10, 13, 14). With decreasing palladium content the superstructure lines become weaker and approach the intensity of those of Fe4N. No analysis was made of the intensities, but it can be assumed that the structure is that found by Wiener and Bergerl in Fe3NiN and Fe3PtN, namely L1'2 (perovskite structure) with both palladium and the interstitial nitrogen fully ordered. The dependence of the lattice constant upon the solute atom (Ni, Pd, Pt) content can be explained tolerably well by simple lattice expansion due to subsequent work confirms this suggestion, it will be of significance to order-disorder theory. The author is grateful to Lester Guttman for discussions on this topic.

Jan 1, 1961