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By Brison Robertson, W. P. Fishel

THE carbide-forming tendencies of the various steel-alloying elements, or their affinities for carbon, is a subject that has received considerable attention, but little more than a probable arrangement of the elements as to their carbide-forming tendencies has been proposed. The physical properties of alloy steels depend upon the relative proportions of the elements present and their combinations. One important phase of this subject is the distribution of carbon between the various elements present. The distribution of carbon between iron and other elements evidently will depend upon: (I) the affinity of each for carbon; (2) the relative atomic masses of the elements present; and (3) the possible formation of compounds between the alloying elements and iron and between the elements themselves. In ternary steels the case is simplified, especially in systems in which the element and iron form no compounds. In such systems iron and the alloying element are competing for the carbon present. In this work the distribution of carbon between titanium and iron has been studied by measuring the relative amounts of iron carbide and titanium carbide present in a series of annealed steels in which the ratio of titanium to carbon extended from 0.527 to 4.61. EXPERIMENTAL PROCEDURE Ten Fe-Ti-C alloys, weighing about 250 grams each, were prepared by melting under a vacuum, in an induction furnace, Armco iron, carbon-free ferrotitanium (25 per cent Ti), and pure carbon. Vacuum melting prevented the formation of titanium oxides and nitrides, which would complicate the problem. The melts were made in graphite crucibles lined with sintered magnesium oxide. The ingots were cooled in the furnace under a vacuum and were then completely annealed at 950°C. The determination of the amount of titanium carbide present was based upon the established insolubility of titanium carbide in boiling dilute (I :4) sulphuric acid, and the complete solubility of free titanium and titanium-iron compounds in this acid. High-carbon ferrotitanium, which had been treated to remove free Ti and Fe, was found to be completely insoluble in the acid; and the carbon-free ferrotitanium used in making the alloys was found to be completely soluble. Others 1,2 have reported the insolubility of titanium carbide in sulphuric and hydrochloric acids. Turnings from the ingots were digested with boiling sulphuric acid (1:4) until all action had ceased. The carbide residue was filtered off and analyzed for titanium, and in some cases for carbon. This represents the titanium that was united with carbon. The filtrate from the carbide residue contains the portion of the titanium that wasin solid solution in the ferrite. Titanium

Jan 1, 1944

By J. D. A. Morrow

THIS discussion relates to the distribution of coal under the direction of the U. S. Fuel Administration beginning Apr. 1, 1918. At that time a definite method of ' controlling and directing distribution was put into effect. Prior thereto, although some of the machinery utilized was in operation, especially in the few weeks immediately preceding Apr. 1, distribution had not been effectively and comprehensively organized. The writer was called to the Fuel. Administration by Dr. Garfield about the. first of February, 1918, to assume general direction of the distribution of coal for the Fuel Administration, to develop the general plans, and to obtain practical men to assist in this work and in carrying through the program finally devised. A study of the situation and conferences with the Fuel Administrator and leading men in the business made it plain that it would- he necessary to begin at the bottom, measure the undertaking, develop plans to meet the need thus shown, and build an organization to effect the distribution required. This work had to be done under war pressure in the midst of a bad coal shortage. The successful performance of such a task is always primarily a matter of putting competent men in the right places and giving, them the power and opportunity to function properly together. In the Distribution Division of the U. S. Fuel Administration, the men who were chiefly responsible for whipping plans into practical form and then for carrying out these plans were A. W. Calloway, of Baltimore, President of the Davis Coal & Coke Co., who served as the Director of Bituminous Coal Distribution; S. Lovell Yerkes, of Birmingham, Alabama, Secretary of the Grider Coal Sales Agency, who assumed general charge of distribution while the new plans and organization were being perfected and then became the Assistant Director of Bituminous Coal Distribution; Warren S. Blauvelt, of Detroit, who was Director of Coke Distribution; A. S. Learoyd of New York, Director of Anthracite Distribution, in connection with the Anthracite Committee, consisting of Joseph

Jan 3, 1919

By D. Gignac, P. A. Studemeister, H. Koza

Two epiclastic horizons in an Archean volcanic sequence host the gold occurrences on the Dunraine property near Wawa, Ontario, Canada. The Grace horizon of cherty and pelitic tuff strikes northnorthwest and dips east. Native gold occurs with arsenopyrite in bedlike and podlike bodies of quartz lenses and stringers set in a pelitic matrix. The Parkhill horizon of lithic graywacke with associated flow-breccia strikes southwest and dips south, Native gold occurs with minor sulfides in similar bodies of quartz erratic within the Parkhill horizon. The auriferous bodies occupy paleotopographic channels and troughs within the two horizons. The former producers are the Parkhill mine with 1689 kg (54,300 oz) Au, Darwin mine with 473 kg (15,200 oz) Au, and Van Sickle mine with 48 kg (1536 oz) Au between 1902 and 1944. The gold occurrences are syndepositional with the host volcanic sediments laid during a pause in explosive volcanism. Fumaroles along steep gullies on the flank of a subaqueous volcanic center precipitated aprons of auriferous silica-sulfide mud. Downslope slumping resulted in exhalative debris flows; gold concentrated in flexures and depressions along slumpage channels. Renewed explosive volcanism covered the auriferous sediments with pyroclastic tuffs, arresting the slumping of in situ fumarolic deposits.

Jan 1, 1986

By Richard V. Wyman

Leaching of a granitic rock mass by slightly acid groundwater brings uranium and genetically related ions into solution in groundwater. Uranium and related ions are moved through the vadose zone by groundwater which in turn moves through zones of greatest transmissivity into a deep zone of increased hydrostatic pressure. Cyclic wetting causes the hydrostatic condition to fluctuate causing recycling described by Gruner (op cit). Multiple cycling flushes the uranium ions from rock being leached and moves it via this method to permeable beds-channels-in the deep zone.

Jan 1, 1970

By Walter Scott

THE removal of lead by fire refining methods from copper of electrolytic quality is growing in importance. Particularly is this true of the refining of secondary copper and copper cathodes obtained from electrolytic cells where lead is used as the anode material, as in the electrolysis of ore-leaching solutions and foul electrolyte. When investigating the removal of small amounts of lead from molten copper in a reverberatory furnace during the refining of secondary copper of otherwise electrolytic copper quality,1 it was found necessary first to FIG. 1.-SAMPLING DEVICE. know something about the distribution of the lead throughout the bath. The authors believe that it is not generally known how small amounts of lead as an impurity are distributed in a molten copper bath; that is, whether the lead is concentrated at the bottom or at the top, or whether it occurs more or less uniformly throughout the bath. The data contained in this report may help, therefore, in the development of a satis-factory fire refining method for the removal of this obstinate element from a molten copper bath.

Jan 1, 1930

By B. M. Larsen, L. S. Darken

SOME years ago we collated all laboratory data then available to us on the distribution at equilibrium of manganese and of sulphur between metal and simple slags, and used the results in setting up an equation, which proved to be in accord with determinations of the distribution ratio of manganese and of sulphur between liquid steel and open-hearth slag, over a wide range of operating conditions. We now present an outline of our calculations and inferences on these two closely related questions, which are of especial importance because of the advisability of conserving manganese wherever possible. In general, our results show that in the open-hearth furnace equilibrium between metal and slag, with respect to both manganese and sulphur, is substantially attained during the finishing period of the heat, or in about a half hour to an hour after any additions were made. This implies that the end result will be identical whether manganese is added as alloy or metal to the liquid steel or as oxide to the slag. The proportion of total manganese retained by the steel is favored: (I) by use of the minimum amount of lime, consistent with other operating limitations, required to give a lime-silica ratio of about 2.4, which usually corresponds to a minimum practical slag volume; (2) by a high concentration in the slag of MnO relative to FeO; (3) by high operating temperature. Absorption of sulphur by the slag from the liquid metal is favored: (I) by large slag volume; (2 by a high concentration of active (or "free") lime and of manganese oxide dis) solved in the slag; (3) by low concentration of silica, iron oxide, and phosphate dissolved in the slag. DISTRIBUTION OF MANGANESE BETWEEN SLAG AND METAL AT EQUILIBRIUM On the basis that the distribution of manganese between liquid steel and slag is controlled by the reaction [FeO + Mn = MnO + Fe [A]slag metal slag metal] the distribution at equilibrium, at a given temperature, is expressed by the equilibrium constant for this reaction, which is defined as [K" aMoO aFeI1 dFec) aMn] where a is the activity of the molecular species denoted by the subscript. The activity of each of the several components, although it is not known precisely, is approximately equal to the concentration of each component expressed as its mol fraction; that is, as the ratio of the number of mols of the given component to the total number of mols of all the molecular species present in the metal or slag, as the case may be. Moreover, since the activity, or concentration, of iron in the liquid metal is in fact substantially constant, the term [afe] may be combined with K" to give a new constant K'. Making these changes,

Jan 1, 1942

By B. M. Larsen, L. S. Darken

SOME years ago we collated all laboratory data then available to us on the distribution at equilibrium of manganese and of sulphur between metal and simple slags, and used the results in setting up an equation, which proved to be in accord with determinations of the distribution ratio of manganese and of sulphur between liquid steel and open-hearth slag, over a wide range of operating conditions. We now present an outline of our calculations and inferences on these two closely related questions, which are of especial importance because of the advisability of conserving manganese wherever possible. In general. our results show that in the open-hearth furnace equilibrium between metal and slag, with respect to both manganese and sulphur, is substantially attained during the finishing period of the heat, or in about a half hour to an hour after any additions were made. This implies that the end result will be identical whether manganese is added as alloy or metal to the liquid steel or as oxide to the slag. The proportion of total manganese retained by the steel is favored: (I) by use of the minimum amount of lime, consistent with other operating limitations, required to give a lime-silica ratio of about 2.4, which usually corresponds to a minimum practical slag volume; (2) by a high concentration in the slag of MnO relative to FeO; (3) by high operating temperature. Absorption of sulphur by the slag from the liquid metal is favored: (I) by large slag volume; (2-by a high concentration of active (or "free") lime and of manganese oxide dis) solved in the slag; (3) by low concentration of silica, iron oxide, and phosphate dissolved in the slag. DISTRIBUTION OF MANGANESE BETWEEN SLAG AND METAL AT EQUILIBRIUM On the basis that the distribution of manganese between liquid steel and slag is controlled by the reaction [FeO + Mn ;7± MnO + Fe [A] slag metal slag metal] the distribution at equilibrium, at a given temperature, is expressed by the equilibrium constant for this reaction, which is defined as [K" aFPI OFeO ? aMn] where a is the activity of the molecular species denoted by the subscript. The activity of each of the several components, although it is not known precisely, is approximately equal to the concentration of each component expressed as its mol fraction; that is, as the ratio of the number of mols of the given component to the total number of mols of all the molecular species present in the metal or slag, as the case may be. Moreover, since the activity, or concentration, of iron in the liquid metal is in fact substantially constant, the term aFe may he combined with K" to give a new constant K'. Making these changes.

Jan 1, 1942

By D. Harper

The National Pocahontas Mine in Wyoming County, WV, has been developed in the Pocahontas No. 3 coal. During 14 months of ventilation surveys, the locations of large rockfalls, many in areas infrequently visited by mine personnel, were mapped. Several dozen rockfalls were later studied in detail. Kettlebottoms, rider seams, root-penetrated roof strata, slicken sides, and shales that spall are common in areas with a high density of rockfalls. Large-scale crossbedding and micaceous and carbonaceous films in sandstones are less common. Density of rockfalls in any area is related to the time elapsed since mining, thickness of overburden, and orientation of entries and panels. Some linear features overlie areas where rockfalls are densest. Most rockfalls occur during summer.

Jan 1, 1983

By Louis D. Huntoon

SHORTLY after publication of the article in the July, 1924, issue Of MINING AND METALLURGY, entitled "Canada as a Gold Producer," requests were received to determine the ownership of production. Advices have also been received that considerable discussion has taken place on the same questions both in Canada and Great Britain. The author is indebted to R. H. Coates, Dominion Statistician, and George C. Bateman, Secretary, Ontario Mining Association, for the following figures and takes this opportunity of expressing his appreciation. There have been no statistics compiled as to ownership of production. Statistics were compiled as of Dec. 31, 1921 relative to the distribution of stocks, bonds and "other securi¬ties" in industrials, agriculture excepted, throughout the Dominion, and "distribution of ownership of securities issued by mining companies incorporated and operating in Ontario" for the same year. Stock registration does not necessarily represent actual ownership' as large blocks may be endorsed and not transferred; neither does registration actually represent production. When the charts are studied individually and collectively one cannot help but be impressed with the fact .that in the mineral industry of Ontario and the Dominion at large, Canadian registration predominates, the United States registration is about half that of Canada, and Great Britain is about half that of the United States. When the nickel-copper industry is excepted the British registration falls to a very low percentage. Since Dec. 31, 1921, British capital has commenced to flow into mining enterprises in Ontario and it has been already rewarded by the discovery of valuable ore deposits.

Jan 1, 1925

By Samuel Lasky

THE writer has been interested in determining the mineralogic dis-tribution of silver in the base-metal ore of the Ground Hog mine of the Asarco Mining Co. in the Central mining district of New Mexico.1 This ore consists of a varitextured mixture of sphalerite, chalcopyrite, galena and pyrite in a quartz gangue. The average ore contains 14 per, cent of zinc, 9.5 per cent of lead, 5 per cent of copper, and 10 oz. of silver per ton. Generally it is accepted that the silver in ores of this type, in which no definite silver minerals can be recognized, is contained in the base-metal minerals. Published assays of pure mineral specimens from many dis-tricts show that each of the base-metal minerals contributes in some degree to the total silver content of the ores, and to determine the pro-portionate amount contributed by each mineral in any specific ore it has been the practice to assay selected specimens of each mineral, the purity of which has been determined microscopically. There being no such assays available for the Ground Hog ore, and it being impract cable to have enough of them made to give average results, the writer resorted to a mathematical attack upon composite assays of large quantities of ore and concentrates. Surprising results were obtained, and it is the threefold purpose of this paper to present these results, to describe the mathe-matical method used, and to point out the value of using this method even when assays of pure specimens are available.

Jan 1, 1934

By Frank W. Harris

THE strength of hard drawn copper wire is a question of considerable importance to both manufacturer and consumer. Unlike steel and alloy wires, in which strength is governed by both chemical and physical considerations, the high conductivity required for copper wire in the electrical industry generally precludes the possibility of obtaining tensile strength through the use of alloys. Consequently, this strength is largely a matter of the physical structure, and all factors known to affect this structure, such as rolling temperature, die contours, lubricants, drawing speeds, etc., are matters of prime importance. The experiments described here have been carried out during the past year at the Baltimore plant of the American Smelting & Refining Co., in connection with a general investigation of some of the questions mentioned above, with the object of studying the physical structure of hard drawn copper wire and the influence of certain factors on that structure. The work has been of an exploratory nature, rather than comprehensive, but it was thought that the results might prove of sufficient general interest to warrant their publication. The bulk of the hard drawn copper wire used in places where strength is an important factor is manufactured to strict specification, based usually in the United States on that of the American Society for Testing Materials (B-1-23). This specification calls for almost as high a value of tensile strength, consistent with elongation, as it is possible practically to obtain, and only physically perfect material can be relied on to meet such a specification. Obvious defects, such as laminations produced through fins in the original rods or brittleness due to overdrawing, are usually recognized and need only passing reference. Laminations can be detected by twisting and untwisting the wire several times; they will show up on the surface in the form of fins. Fig. 1 shows a very bad example of this defect. The wire may be perfectly smooth before twisting but when such laminations are present they will readily show up under this treatment. This trouble is caused by similar defects in the original rod produced by overfills in rolling. Fig. 2 shows the cross-section of the rod from which the wire in Fig. 1 was drawn.

Jan 1, 1928

By Frank Harris

THE strength of hard drawn copper wire is a question of considerable importance to both manufacturer and consumer. Unlike steel and alloy wires, in which strength is governed by both chemical and physical considerations, the high conductivity required for copper wire in the electrical industry generally precludes the possibility of obtaining tensile strength through the use of alloys. Consequently, this strength is largely a matter of the physical structure, and all factors known to affect this structure, such as rolling temperature, die contours, lubricants, drawing speeds, etc., are matters of prime importance. The experiments described here have been carried out during the past year at the Baltimore plant of the American Smelting & Refining Co., in connection with a general investigation of some of the questions mentioned above, with the object of studying the physical structure of hard drawn copper, wire and the influence of certain factors on that structure. The work has been of an exploratory nature, rather than comprehensive, but it was thought that the results might prove of sufficient general interest to warrant their publication. The bulk of the hard drawn copper wire used in places where strength is an important factor is manufactured to strict specification, based usually in the United States on that of the American Society for Testing Materials (B-1-23). This specification calls for almost as high a value of tensile strength; consistent with elongation, as it is possible practically to obtain, and only physically perfect material can be relied on to meet such a specification. Obvious defects, such as laminations produced through fins in the original rods or brittleness due to overdrawing, are usually recognized and need only passing reference. Laminations can be detected by twisting and untwisting the wire several times; they will show up on the surface in the form of fins. Fig. 1 shows a very bad example of this defect. The wire may be perfectly smooth before twisting but when such laminations are present they will readily show up under this treatment. This trouble is caused by similar defects in the original rod produced by overfills in rolling. Fig. 2 shows the cross-section of the rod from which the wire in Fig.1 was drawn.

Jan 1, 1928

By J. W. Halley, T. S. Washburn

RIMMING steels derive their name from their action during solidification in the molds. As a result of incomplete deoxidation, gas is evolved during freezing, and the metal has a characteristic rolling action. The metal rises along the mold walls and descends in the center of the ingot. This action keeps the top of the ingot open and the advancing rim of solid metal can be seen. The rim grows until the rolling action is insufficient to prevent the top of the ingot from freezing or until the action is stopped by capping the ingot with a heavy plate. The violence of the reaction and its characteristics, such as growth or drop in the molds, are determined by the composition, the furnace practice, and the deoxidation in the ladle and in the molds. Though rimming steels represent a large proportion of the amount of plain carbon steel made, they have received comparatively little attention in the technical literature. The manufacture of rimming steels has been described by Hibbard, 1, 2 Fleming,3 Pierce4 and Jackson.5 The reactions occurring during rimming have been considered from the theoretical point of view by Chipman and Samarin.7 The structure of rimmed-steel ingots has been discussed by Nead and one of the present authors.6 Meyer,8 in studying segregation, investigated the distribution of carbon, sulphur and phosphorus in rimmed-steel ingots by analyzing the rim and core of blooms. In their studies of segregation, the Joint Committee of the Iron and Steel Institute and the British Iron and Steel Federations studied distribution in one billet and one ingot of rimmed steel.. A detailed study of the distribution throughout the ingot has not been published. The present investigation was undertaken to determine accurately the distribution of carbon, manganese and sulphur in normal rimmed ingots and the general distribution of other common elements present. The study included some work on the effect of pouring conditions and furnace practice on the distribution, though there is still much to be done in this direction. The structure of a rimmed ingot that has been split by dynamiting and a schematic diagram of the zones in the ingot are illustrated in Fig. 1.

Jan 1, 1938

By J. W. Halley

RIMMING steels derive their name from their action during solidifica-tion in the molds. As a result of incomplete deoxidation, gas is evolved during freezing, and the metal has a characteristic rolling action. The metal rises along the mold walls and descends in the center of the ingot. This action keeps the top of the ingot open and the advancing rim of solid metal can be seen. The rim grows until the rolling action is insufficient to prevent the top of the ingot from freezing or until the action is stopped by capping the ingot with a heavy plate. The violence of the reaction and its characteristics, such as growth or drop ill the molds, are deter-mined by the Composition, the furnace practice, and the deoxidation in the ladle and in the molds. Though rimming steels represent a large proportion of the amount of plain carbon steel made, they have received comparatively little attention in the technical literature. The manufacture of rimming steels has been described by Hibbard,1,2 Fleming,3 Pierce4 and Jackson.5 The reactions occurring during rimming have been considered from the theoretical point of view by Chipman and Samarin.7 The structure of rimmed-steel ingots has been discussed by Nead and one of the present authors.6 Meyer,8 in studying segregation, investigated the distribution of carbon, sulphur and phosphorus in rimmed-steel ingots by analyzing the rim and core of blooms. In their studies of segregation, the Joint Committee of the Iron and Steel Institute and the British Iron and Steel Federations studied distribution in one billet and one ingot of rimmed steel. A detailed study of the distribution throughout the ingot has not been published. The present investigation was undertaken to determine accu-rately the distribution of carbon, manganese and sulphur in normal rimmed ingots and the general distribution of other common elements present. The study included some work on the effect of pouring condi-tions and furnace practice on the distribution, though there is still much to be done in this direction.

Jan 1, 1938

By E. C. Simmons

Uranium is an incompatible element with respect to the major rock-forming minerals crystallizing from granitic magma, entering instead trace minerals such as zircon. The relationship between the saturation limit (SL) for such a mineral and the bulk distribution coefficient (Do) for U is central to understanding the distribution of U and its availability to late-stage fluids that can form ore deposits directly, or labile U that can be remobilized later. Low SL values imply early crystallization of zircon, but in very small proportions, minimizing Do and maximizing the degree of enrichment of U in late-stage fluids. Thus, granitic rocks with low Zr contents (due to a low saturation limit for zircon) are most likely to evolve U-enriched differentiates; this will be reflected in a high U content of the zircons (but not necessarily high U abundances in whole-rocks). Thus, the ratio of the U content of zircon to the Zr content of the corresponding whole-rock is potentially a very useful parameter in identifying granitic rocks most likely to have U-enriched solutions associated with them. The granitic rocks associated with the U deposits of the Midnite mine area, Washington, have geochemical characteristics that fit the model presented very well. The rocks are very low in Zr (100 ppm) and contain zircons with extremely high U contents (3,000-4,000 ppm).

Jan 1, 1984

By J. E. Dreier

The Pachuca - Real del Monte district has produced about 46.6 kt (51,300 ton) Ag from subvolcanic vein deposits. Three types of wall rock alteration are spatially related to the veins: K-feldspar, propylitic, and phyllic. K-feldspar alteration occurs within veins; propylitic alteration occurs in fractured rocks between veins; and phyllic alteration occurs above veins. Concentrations of some trace elements in altered rocks relative to unaltered rocks are summarized below. [ ]

Jan 1, 1983

By Alan D. Hoagland

The Flat Gap mine, are important zinc deposit of the Appalachian type, is located in the Copper Ridge Belt in the Valley of Tennessee approximately 30 miles northeast of the Mascot-Jefferson City zinc district (Fig. 1). The ore is found in large stratigraphically linked deposits in solution and collapse breccias of the Kingsport, Longview and, to a minor extent, Mascot formations of Lower Ordovician age. The principal ore mineral is sphalerite and the principal gangue minerals are dolonmite and accessory pyrite. There is local minor galena and very rare barite and fluorite.

Jan 10, 1962

By E. L. Brack

ASARCO's copper smelter at Hayden, Arizona has been upgraded to meet the increasing Environmental Protection Agency (EPA) and Occupational Safety and Health Administration (OSHA) environmental standards. Fortunately, means were found to accomplish these standards and provide for more efficient operations. With the adaptation of oxygen flash smelting and other related operations at Hayden, ASARCO has turned to the use of minicomputers and microprocessors for inter-plant communications and local area process control. The applications of distributive and computer controls to the plant operations at the Hayden smelter are discussed in this paper.

Jan 1, 1984

Suggestions for Directorial representatives should be submitted by the District Committees between November 1 of the year indicated and the following Annual Meeting District 1 New York Section (Each Year) District 2 Boston (1950) Pennsylvania Anthracite (1951) Lehigh Valley (1952) Philadelphia (1953) Connecticut (1954) Adirondack (1955)

Jan 1, 1952

By J. L. Huiatt, M. C. Fuerstenau, M. C. Kuhn

Dithiophosphatogen is the species responsible for flotation of pyrite when dithiophosphate is added as collector. Oxidation of collector apparently occurs by reaction with oxygen adsorbed on the pyrite surface. Oxidation of dithiophosphate and xanthate is also effected with Cu++, Cu(OH) , and Fe+++ and rates of oxidation are presented as a function of pH. Reasons for the selectivity observed when dithiophosphate is added as collector in a natural ore system as compared to xanthate are presented and discussed.

Jan 1, 1972