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By Frederic Benard

THIS paper constitutes a preliminary report on experimental work done to date on the anode-furnace treatment of blister copper containing relatively high percentages of nickel. The investigation has not been completed but results obtained to date are considered of sufficient interest to warrant publication. Blister copper treated by the Ontario Refining Co. originates from the Copper Cliff smelter of The International Nickel Company of Canada, of which the former is a wholly-owned subsidiary. The blister as received contains from 0.50 to 1.50 per cent Ni, and in this respect differs from that treated by other refineries on this continent. During the anode-furnace treatment, only a portion of the nickel content is removed, and of the amount remaining in the anodes a varying percentage is found in the anode slimes. This necessitates a more extensive treatment than ordi-nary, nickel-free material. Sometimes it is necessary to repeat roasting and leaching operations several times before the nickel content is low enough to permit the slimes to proceed to the doré furnace. This, besides increasing treatment charges, causes greater selenium stack losses and involves a longer tie-up of precious-metal values. Therefore this investi-gation was undertaken with the aim of determining the factors influencing the diversion of nickel into the anode sludge. From experience it was known that by keeping the nickel content of anodes at 0.55 to 0.60 per cent maximum a relatively satisfactory slime resulted. One avenue of attack therefore was developing improved elimination in the anode-furnace treatment so that the anode content mentioned above was not exceeded. Another angle was to improve the solubility, during electrolysis, of the nickel constituent in the anodes, thus decreasing the percentage diverted to slimes. It may he mentioned here that nickel dissolving electrochemically and entering the electolyte pre-sents no difficulty from a treatment standpoint. Both of these approaches were studied and are discussed sepa-rately below.

Jan 1, 1938

By Reino Kurppa

The Pyhäsalmi mine of the Outokumpu Co. is located in central Finland (Fig. 1). The deposit was discovered in the autumn of 1958. Construction of the mine was started a year later, and production began on Mar. 1, 1962 (Fig. 2). At present, 750,000 metric tons (mt) of ore and a nearly equal amount of country rock are mined annually. Slightly over one-half million tons of various concentrates are produced per year, of which 85% is pyrite concentrate, 10% zinc concentrate, and 5% copper concentrate. The pyrite concentrate is treated in the company's pyrite smelter,1 yielding elementary sulfur, sulfur dioxide, and iron-oxide cinders, as well as electric power. Thus all the sulfides, totaling 75% of the ore, are of economic value. This is a fact which had a bearing on the development of the stoping method. GEOLOGY The ore is of breccia type containing fragments of country rock of varying sizes. It is coarse-grained pyrite ore containing sphalerite and chalcopyrite as a matrix between the pyrite grains. Only small amounts of pyrrhotite have been observed in certain marginal parts of the orebody. The ore averages 0.85% Cu, 3.0% Zn, 38% S, and 33% Fe. The orebody extends from the surface down to at least 500 m, which is the lowest level from which present information has been obtained. Horizontally, the orebody is 650 m long. It is 75 m wide at its central part, narrowing towards the ends (Fig. 3). At a depth of 115 m, the orebody suddenly narrows down to a thickness of 25 to 30 m. In the northern part of the orebody, the dip is 50° to 70°, but elsewhere it is almost vertical (Fig. 3).

Jan 1, 1969

By M. L. Requa

IN the fall of 1910, the Nevada Petroleum Co., operating in the Coalinga field in California, determined to drill a number of wells with rotary tools, in order to prove conclusively the relative value of the rotary as compared with the standard rig. At that time, the rotary was but little known in California and its proposed introduction met with considerable criticism on the part of the operators and quiet opposition among the standard drilling crews. There were few men available who were competent to handle a rotary outfit, and these few had had but little experience in California fields. Machines as then built were much inferior to those now used, being lighter in construction and of a poorer quality of material. The shells encountered at depths between 1,700 and 2,000 ft. seemed to be too hard to permit of successful drilling, and at these depths the rig was changed over to standard tools and by them completed. Because of the heavy depreciation, the time lost in converting from rotary to standard, and the comparatively small profit, it was concluded that unless in the future there was some material improvement in rotary rigs, nothing would be gained by drilling with rotary tools upon this property. Little or no drilling has been done upon the property since that time, but in the meantime a large number of men have been trained in the use of the rotary; in fact, many standard-tool men have abandoned standard drilling and, starting in as roustabouts, have become thoroughly competent rotary operators. The improvements in the machinery have been such as to remove many of the objections and the rotary drilling of to-day is in every way superior to that of 1910. In contrast, a well drilled recently by the Kern Trading & Oil Co., in the east side Coalinga field may be cited. The first 2,500 ft. was drilled in 24 days and it is confidently expected that the water string will be set with a rotary at 3,400 ft.-a record obviously far beyond that made in 1910 by the Nevada Petroleum Co.

Jan 2, 1915

By Walter Voskuil

ILLINOIS supplies coal to seven states in the Upper Mississippi Valley -Illinois, Missouri, Iowa, Minnesota, Wisconsin, and portions of the Dakotas, Nebraska and Kansas. In this same area are marketed large quantities of coal from West Virginia, Kentucky, Pennsylvania, and else-where; fuel oil from the crude petroleum supplies of the Mid-Continent fields, and natural gas from Louisiana, Kansas and the Texas Panhandle. The boundaries of this "Illinois coal-market area" are determined by competition from other coal fields and from other forms of fuel. Within the area so described 90 per cent of Illinois coal is marketed. Thus in the Southwest, an abundance of fuel-oil supplies and natural gas domi-nates the market almost to the exclusion of coal. The westward move-ment of Illinois coal in Kansas, Nebraska and the Dakotas is met by an eastward flow of high-grade coals from Colorado, Wyoming and Montana. In the lake-shore counties of Minnesota and Wisconsin, the market is dominated by Appalachian coals, cheaply carried over the Great Lakes and reaching the ports of Lake Michigan and at the head of Lake Superior. Illinois coals find their largest market in the southern and western sections of these two lake states. Only small quantities of Illinois coals are shipped east of the state line. This market area is occupied entirely by the neighboring coal fields of Indiana and the Appalachian coal fields in Ohio, West Virginia, Kentucky and Pennsylvania.

Jan 1, 1936

By C. H. Jr. Herty

THE elimination of metalloids in the open-hearth process depends on oxidation of the metal by diffusion of FeO from the slag (or absorption of FeO by the metal), with subsequent reaction between dissolved iron oxide and the metalloids carbon, manganese, phosphorus, and silicon. During an investigation on deoxidation with silicon, data on rate of oxidation of the metal were obtained, and these combined with certain other information, are presented here in an attempt to show the fundamental principles governing the diffusion of FeO from slag to metal. Inasmuch as the aim of the investigation was not a study of diffusion, certain data are lacking and it has been necessary to make assumptions on metal viscosity and effect of temperature on diffusion. These factors are known to exert a considerable effect on diffusional processes. Overoxidation, or supersaturation of the metal with iron oxide, is not taken up in this paper. Overoxidation has little effect on diffusion except under a few special conditions, and the discussion has therefore been limited to diffusional processes. Though the results given in this paper should be regarded as preliminary, certain of the conclusions drawn are definitely applicable to any steelmaking process.

Jan 1, 1929

By M. J. McPherson

Having worked on the thermodynamics of air/liquid-water mixtures passing through the surface fans of deep mines, I find this paper of great interest and congratulate the authors on producing it. There are two matters, however, deserving discussion. First, the authors have described the classical theory of fog formation with fogging occurring at "supersaturation." In fact, the process of fog formation begins well below 100% humidity. The more strongly hygroscopic nuclei in the atmosphere will attract water molecules and begin to grow at a relative humidity perhaps as low as 70%. The process is a dynamic one with both condensation and evaporation taking place throughout the mixture on microscopic liquid surfaces. As saturation is approached, the rate of condensation accelerates rapidly producing the familiar reduction in visibility. Hygroscopic nuclei are present in all natural atmospheres and under the appropriate conditions of pressure and temperature, will produce clean fogs. However, if the air is polluted by particulates from combustion or other processes then the resultant coagulation with growing liquid particles may produce dense (and sometimes photochemical) smogs. It is this process that is likely to occur in underground mines when moist air is cooled below dew point. Second, the authors have summarized very well the individual measures that might alleviate the problem. In particular, I agree that neither heating nor refrigerating the air, by themselves, provides a satisfactory solution. However, there is a combination of these that provides a neat and effective control of fog formation. This involves a small, self-contained refrigeration unit within a duct but without the usual external heat rejection facility. The air is cooled below dew point and, hence, dehumidified on passing over the cold evaporator coils. The heat from the condenser is rejected back into the air down-stream from the water eliminator, as shown in [Fig. 1]. The duct configuration can be designed to create good mixing at the outlet.

Jan 1, 1984

By Earl H. Miller, Henry H. Bruhn

COMMERCIAL beds of sylvite ore were discovered by the Snowden & McSweeney Co. while drilling a wildcat oil well some 25 miles northeast of Carlsbad, N. NI., in 1925. After a preliminary core drilling program the U. S. Potash Co. sank a 1060-ft shaft within 4 miles of the original discovery. This shaft was in an isolated location in a sand desert area with only the roughest of dirt roads connecting it with the neigh- boring town of Carlsbad some 21 ½ miles west.

Jan 6, 1954

By Oswald J. Heinrich

This question having been repeatedly raised, and particularly revived in a discussion at the last meeting of the Institute, I beg to submit the following remarks, based partly upon personal experience, partly upon the results of large works in Europe, establishing, years ago, the practicability of certain methods, which may therefore be considered to have passed the stage of mere experiment. Before entering upon the merits of one system or the other, it is indispensable to lay down some recognized principles, which ought to serve as guides, in arriving at fair judgments in questions of this character. In a profession like that of mining, locally so much influenced by combinations of circumstances too various to mention, it is difficult to do more than lay down the main features of a system based upon general laws and recognized facts, leaving the details to the sound judgment and experience of the engineer, who, by virtue of his education, ought to be able to make such choice and such modifications in the plans of a mine as the particular case demands. Mineral resources, in some countries the sole property of the owner of the soil, in others controlled by the strong hand of a government, are nevertheless a gift of nature, in which, indirectly, the whole of the human race has as real an interest as the immediate owner himself. This interest requires, at least, that no unnecessary waste of

By Leonard P. Skolnick

PROPERTIES of materials containing a hard con-stituent dispersed in a metallic matrix are dependent on the distribution of the hard phase.'-' The grain growth of titanium carbide in liquid nickel was studied in order to understand microstructural development in this and similar systems. Smith" has examined the influence of surface energy on the distribution of phases in alloys. The grain growth of tungsten carbide in cobalt has been the subject of many conflicting theories. Those prior to 1950 have been summarized by Goetzel.' Recently, Gurland and Norton3 and Gurland8 have indicated that growth occurs primarily by diffusion through the liquid phase in order to lower the inter-facial energy between the carbide and the liquid metal. In the development of the Ti-C-Ni ternary phase diagram, Stover and Wulff9 have shown that both eutectiferous dendritic titanium carbide, and primary titanium carbide which had developed crystals of cubic symmetry, were rounded by heating below the solidus, and that if primary carbide was already present the typical eutectic decomposition products were not formed. Experimental Procedure The infiltration technique was used to study the grain growth of titanium carbide in nickel. In contrast to sintering, infiltration more readily assures uniform dispersion of the two phases, and the problems associated with mixing by milling; i.e., mill contamination, breakdown of original carbide size in the operation, development of interfering surface films, etc., are avoided. In addition, the complicating effect of densification by shrinkage is eliminated. The titanium carbides used were commercial grades. Their chemical analyses, size distributions and shapes are summarized in Table I. Size analysis was conducted by microscopic count on a minimum

Jan 1, 1958

By Carl Henrich

In the winter of 1895 to 1896, during the construction of the Jackson and Cincinnati railroad, running from Addison, Lenawee county, Mich., to Jackson, Mich., in a northerly direction, I had occasion to observe some interesting geological features, described below, in a cut of this railroad made through the low ridge of gravel and sand, dividing the valley of Silver Lake and Silver Creek from the Goose Lake and Goose Creek valley, in Lenawee county. The surface-deposits of this part of the county are, as is well known, of glacial origin. Gently rounded, long ridges of sand, gravel and clay intervene between the marshy bottoms and the lakes of the valleys. The nature of the deposits, varying from a sandy clay or clayey sand to fine and coarse gravel and pure siliceous sand on the one hand, and to a very tough, fine, uniform and often indurated clay on the other, as well as the irregular and sudden changes, sharply divided, between these materials composing the ridges, in the cuts made through them by the railroad, would admit of no doubt that this country owes its present surface-configuration primarily to the action of the last glacial period, which covered its surface with an immense ice-sheet. The well-known ice-markings on the huge granite, schist, greenstone and conglomerate boulders found everywhere imbedded and protruding from the surface, add their testimony to the other characteristics mentioned. Most of the cuts made by the railway through the ridges showed in a marked degree the irregular arrangement and the sudden changes of and between the materials mentioned above. One cut, however, known as Kelly's cut, or Kelly's gravelpit, about 4 1/2 miles north of Addison, and about 1 1/2 miles south

Jan 1, 1897

By Cyril Wells, Robert F. Mehl

THE two earlier papers in this series1,2 presented data on the rate of diffusion of carbon and of manganese in gamma iron. Apart from their scientific interest, these [] data are needed chiefly in order to treat data on carburization, on the rate of formation of pearlite, and on the rate of austenizing in a quantitative way. 1,2,9,10 In the present investigation rates of diffusion of nickel in -?-Fe over wide temperature and concentration ranges have been determined, and the effects of carbon, of impurities, and of grain size on these rates have been studied. Claussen,3 using the data of Fry,4 has calculated the diffusion coefficient of nickel [ ] in -?-Fe as 9.2 X 10-11 sq. cm. per sec. at 1200T., but had no data from which to calculate the variation of D with concentration, temperature, and percentage of carbon. METHOD AND MATERIALS Method.-Nickel was diffused along the axis of a cylindrical specimen across a concentration gradient, concentration-penetration curves were determined and D values calculated from Grube or Matano solutions.5 Details of the method are given

Jan 1, 1941

By R. Dawson Hall

THE stresses in the e simplest structures are often those we find most difficult to analyze. The most complex condition in mine stresses is found in simple tunnels where the roof, the sides, and the floor are a monolith. The functions of the parts are like the parts themselves not distinct and specialized, and the problems to be solved are like those in a metal structure with riveted joints or a redundancy of bars. This difficulty explains perhaps why the condition has not been treated. But just because it cannot be discussed in its entirety is no reason why it should be treated as an action of parts with specialized functions as a roof 'beans with supports and a foundation. The problem cannot be ignored on the ground that it is not of sufficient importance to warrant careful consideration, because conditions of complete monolithism, of which the tunnel is the type, are found materially unchanged) in room-and-pillar and in longwall work. This unity between roof, sides, and floor, which to the coal miner is a difficult conception, really deserves a scientific appellation, and perhaps holoid (from holos, whole, and eidos, form) will serve the purpose as well as any other. In a simple tunnel the roof, the sides, and the floor form integral parts of one and the same structure; and the distortion of one cannot be conceived without a consequent strain in the others. Thus when the roof of the tunnel droops by reason of its weight, the upper parts of the sides are drawn in because they are integrally-connected with the roof and must approach each other whenever, by the sagging of the roof, the distance between any two points in it is diminished. (See Fig. 1.)

Jan 9, 1915

By Alden Greninger

ALTHOUGH the crystallography of lattice transformations has been studied extensively during the past few years, these studies have been limited, with few exceptions1,2, to specimens in which the transformed lattice appears as a, segregate phase. A realization of the technical importance of the segregation mechanism, especially in the formation of martensitic structures and in age-hardening phenomena, has undoubtedly stimulated research in this direction. In the crystallographic studies of segregation, the general problem has been to relate the orientation of the parent crystal to that of the segregate crystals. The technique has been complicated by the fact that it has been necessary to deal with the presence of as many as 24 ideal segregate orientations within one parent lattice; furthermore, the segregate lattices are invariably scattered (seldom less than ±2°, often as much as 15° or 20°) about these ideal positions. It is probable that a more complete picture of phase transformations may result from a study in which complete lattice relationships between individual grains are evaluated, thereby providing an additional param-eter which, when it is necessary to work with multiple segregate-orienta-tions, cannot be evaluated. The present paper presents the results of such a study, ? wherein a peritectic reaction is made use of to produce the transformed lattices.

Jan 1, 1937

By C. K. Leith, W. J. Mead

In 1911, we published in the Transactions a brief account of the lateritic alterations of serpentine in eastern Cuba, producing the important iron-ore deposits of the Mayari and Moa districts.' The special feature of that article was a quantitative treatment of the alterations, based on analyses, to show just what had happened in terms of chemical, mineralogical, and physical changes. Professor Kemp has published an interesting account of these ores, containing additional quantitative observations of his own, tending essentially to confirm the nature of the changes that had been worked out.2 His discussion suggests to us the desirability of publishing certain additional quantitative data which were not included in our previous article. This seems especially desirable because quantitative measurements of lateritic alterations are rare, and this particular case may be regarded as typical of a fairly wide range of alterations of this kind. At the time of our examination of Mayari and Moa deposits 29 complete analyses were supplied us by the chemists of the Spanish-American Iron, Co., representing a graded series from the unaltered serpentine rock below to the ore at the surface. These analyses are given in the accompanying table. The mineralogical composition of the ores and rocks is comparatively simple and can be easily calculated from the analyses. In Fig. 1 the mineralogical changes from the serpentine rock below to the lateritic iron ore above, based on the analyses, are expressed in terms of weight, assuming alumina to have remained constant during the alteration. It is not easy by mere inspection of this table of analyses to determine what the progressive chemical changes have been in development of the ore. In order to bring this out clearly, the analyses have been graphically represented in Fig. 2 in such a fashion as to show the progressive additions and losses of substances during alteration.

Jan 1, 1916

By S. Korman, S. B. Tuwiner

Chalcocite flotation is affected by agitation intensity during conditioning. Sodium sulphide in minute quantity may activate or depress, depending on conditions. Oxygen is a depressant while oxygen and sulphide neutralize each other by re-action at the mineral surface. Diffusion across a stagnant film at the surface governs reaction rates, while film thickness is reduced upon increase of agitation intensity.

Jan 2, 1950

By H. U. Schutt, J. M. Toguri

REGARDLESS of the degree of purification effected during the electrorefining of copper, a danger of re-introducing impurities exists in the operation of melting and casting of the refined copper. Logically only a combination of the purification and casting operation would remedy the situation. A well-known method of metal purification is the "Gross"-type process, whereby a volatile halide is produced, purified, and decomposed.' In the present case, this concept was used to remove the impurities rather than to form possible volatile copper halides. The object was to produce volatile halides of the impurities present and distill these away, leaving high-purity copper. It is interesting to note that such techniques are used in spectrographic procedures in order to shorten exposure time and enhance the density of impurity lines.' In the present investigation, copper hydroxy fluoride was used, since the temperature of decomposition of copper hydroxy fluoride and the melting point of copper nearly coincide. The fluorine released by the thermal decomposition of copper hydroxy fluoride purges the molten copper. Copper hydroxy fluoride was prepared by dissolving high-purity copper in nitric acid and adding hydrofluoric acid and ammonium hydroxide in the required proportions. The melt was made in a high-purity graphite crucible heated by an induction furnace. Trial experiments showed that impurities can be introduced from the crucible material. Therefore, preceding each cast, the crucible itself was cleaned by decomposing copper hydroxy fluoride and discarding the residual copper. Best experimental conditions were obtained by adding 30 g of copper hydroxy fluoride to 500 g of nor-

Jan 1, 1967

By B. J. Steblay

Roof bolts are the primary means of supplemental support in coal mines and are widely used in other mines. Presently, post installation loads are measured infrequently on only about 10% of the bolts by using standard torque wrenches that limit accuracy to about ± 30%. Because mine roof bolts are long, slender, non-uniformly sized, roughly forged, placed in a difficult environment, and subject to severe bending on installation, researchers have been unable to use ultrasonic reflection techniques to measure strain. A complete measurement system has now been assembled by the US Bureau of Mines, Denver Research Center. Obstacles such as bolt preparation, transducer mounting, reliable reflection, and calibration have been dealt with. The seemingly simple concept of measuring the time of flight of an ultrasonic pulse to a reflector is actually complex due to the need to measure to 0.0025 mm (0.0001 in.) accuracy, the sensitivity of velocity to temperature, and stress, and the stability required to make measurements over several years.

Jan 1, 1986

By E. H. Denny

IN the past few years many men, including technically trained engi-neers, have been asphyxiated in metal mines, coal mines, tunnels and surface wells where a few relatively simple precautions with regard to ventilation and air testing would have saved them. Death from mine gases is analogous in some respects to death from poison and from drowning. The respiratory passages of a victim who has breathed oxides of nitrogen from burning explosives are badly irritated and a few hours or even a day after exposure he may develop a quick and fatal pneumonia; if, however, he enters without respiratory protective apparatus an atmosphere deficient in oxygen (a condition that may occur in unventilated or poorly ventilated parts of all underground mines) he collapses and if not rescued dies more quickly and surely than a lone nonswimmer who falls suddenly into deep water. An example of an atmosphere virtually without oxygen was demonstrated by an air sample taken by a Bureau of Mines engineer wearing oxygen breathing apparatus in a Cripple Creek shaft some years ago, during the recovery of the bodies of two victims of asphyxiation; analysis of the sample by the Pittsburgh laboratory of the Bureau showed the presence of 18.40 per cent of carbon dioxide, 0.27 per cent of oxygen, and 81.33 per cent of nitrogen, although the atmosphere apparently was clear and normal. In a mine one can pass from good, breathable air to an atmosphere that will kill as quickly as one can dive from a board to deep water below.

Jan 1, 1938

By Clifford Frondel

THE aluminum oxide known as corundum has several varieties that have been used as gem materials since ancient times. These include the red variety called ruby, the blue variety sapphire, and the asteriated types of ruby and sapphire. Asteriated sapphire was known to the ancients under the name of astrios, and descriptions of this gem were given by Pliny and other early writers. The relation of these gem materials to each other as varieties of a single species, corundum, was first clearly established by Haüy in 1805 and J. M. Güthe' in 1809. Natural gem corundum is obtained principally in Ceylon, Siam, Burma, India, and Australia. Star sapphires and rubies always have been highly prized and in recent years have become particu- larly popular in the United States. Natural star rubies of large size and fine quality are extremely rare and rank with large and fine emeralds and diamonds as the most valuable of gem stones. Interest thus attaches to the recent success in commercially synthesizing star sapphires and rubies of a size and perfection unmatched by nature. Corundum was first synthesized as crystals in 1837 by A. Gaudin, who fused alum and aluminum oxide with potassium sulphate. Numerous other syntheses have been reported in more recent years. Summaries of this work are given in Doelter's Hand-buch der Mineralchemie, Mellor's Compreheizsive Treatise of Inorganic Chemistry, and other reference works. The methods employed include the reaction in the gaseous state at high temperatures of halogen compounds of aluminum with water vapor or boric oxide; the crystallization of aluminum oxide from fusion in potassium molybdate, potassium dichrom-ate or borax; and crystallization from highly aluminous silicate melts. Red, blue, or green colored varieties can be obtained by the addition of small

Jan 1, 1955

By C. W. Vaupell

THE Huitzuco mines lie in north central Guerrero, Mexico; production has been about 90,000 flasks of quicksilver since 1873. Near-surface ores fill extinct mud geysers and the deep deposits are chambered veins, stock-works in brecciated blocks, and replacements in limestone. The epigenetic minerals livingstonite, stibnite and sulphur occur in limestone, gypsum and dolomite through a developed vertical range of 260 meters. The deepest workings expose an increased amount of stibnite, which probably indicates that the lower limit of mercury mineralization is being approached. A resur-gence of heat and water formed geysers over an extended area after the period of mercury mineralization. Mud geysers, which are situated, in the outcrops, contain the secondary mercury minerals, cinnabar and barcenite in the gravel and mud filling the vents. A 150-ton flotation plant is in operation concentrating stope fills that assay 3.0 kg. of mercury per ton. In one open stope, which is more than one hectare in area and 60 m. high, 150,000 tons are available.

Jan 1, 1937