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By R. S. Hutton

Jan 1, 1937

In March 1956 a conference on geochemical methods of prospecting for ore deposits was held in Moscow. This conference was the culmination of a ten-year period of extremely rapid increase in both research and routine application of geochemical prospecting methods in the USSR. This activity was divided among groups centered in extremely widely separated bases of operation, ranging from Moscow and Leningrad in the West, Yerevan in the Caucasus, and Alma-Ata in Central Asia to Chita near the Manchurian frontier in the Far-East. The All-Union Conference on Geochemical Methods of Prospecting for Ore Deposits, as the meeting was called, was the first opportunity for these scientists from many parts of the country to meet and exchange experiences. It also served to introduce members of the different research laboratories located in the city of Moscow itself, where adequate channels of technical communication had not yet been established. As a result of the Conference, it was resolved that a concerted effort should be made for the participants to publish the results of their work. Two books have appeared as a direct response to this resolution. I. I. Ginzburg prepared a synthesis of the field of geochemical prospecting for minerals based on the material presented at the Conference. This volume has been translated into English and is now available. In addition, the individual papers presented at the Conference were assembled into a symposium volume and published in 1957 under the editorship of V. I. Krasnikov. Unless otherwise noted, these two books have supplied the source material for the present appraisal of the status of geochemical prospecting in the USSR. It is thus about four to five years old. In the years following the conference, the literature has carried a substantial volume of technical papers, together with a few monographs pertaining to specialized aspects of geochemical prospecting.

Jan 6, 1960

By J. F. Kemp

PAGE Introduction,............170 I. The Competence oF the Igneous Rocks to Supply the Materi als oF Veins,...........171 The Demonstrated Presence of the Metals in the Igneous Rocks,. . 171 The Presence of the Metals in the Sedimentary and Metamorphic Rocks, 173 Conclusions,...........175 The Abundance in Igneous Racks of Vapors or Dissociated Gases which will Yield Water on Emission and Cooling,. 175 The Sequence of Eruptions,. .. . 1 . • .. 78 The Sequence of Vein-Formations,.......1 79 Contact-Metamorphism,.........180 Pegmatites,............181 Frequency of Pneumatolitic Minerals in Veins,.. 183 Surface-Flows of Igneous Rock Unfavorable to Vein-Formation,. . 183

Jan 1, 1902

By D. Harrington

EFFICIENT ventilation of metal mines consists in having such complete control of air currents that. there is always supplied at places where men work sufficient moving air to allow working at maximum capacity without injury to health; and in case of underground fire or of surface fire in the vicinity of mine openings, underground air currents may be quickly reversed if desired, or air may be sent into or excluded from any region and fire fumes confined to only part of the mine workings, instead of penetrating practically the entire mine. Health and safety of workers in mines as well as proper safeguarding and operating efficiency of mining properties are so intimately associated with proper ventilation of mines (both coal and metal) that they are inseparable, yet mine ventilation is only too frequently neglected, especially in metal mines. The metalliferous operator, generally not confronted with inflammable gas or explosive dust which so frequently force ventilation of coal mines, usually disregards air supply altogether except such as may be obtained from compressed air; and generally, even when attention is given to metal-mine ventilation, the air currents rarely are found where they are needed, namely, the working places, especially the working faces. After several years' study of miners' consumption, the writer is. convinced that long continued breathing of air impregnated with large quantities of any kind of finely divided dust, such as is found in a large number of the working places of our mines, will ultimately produce some respiratory disease, whether it be asthma, bronchitis, or phthisis; and the progress of these diseases is hastened. if there are also present high temperatures, high humidities, or harmful gases or if there is present (and allowed to remain to be breathed) large quantities of the finely divided dust when air temperatures are low, hence favorable to maximum performance of work with accompanied maximum breathing into the respiratory passages of the harmful material. It is generally accepted

Jan 2, 1922

By J. T. Eash, E. M. Wise

Many of the platinum metal alloys are hot-forged in the early stages of reduction from ingot and substantial quantities of platinum alloys are commercially employed at very high temperatures in ammonia oxidation units, orifices for forming glass rods and fibers and as cathodes in long-life thermionic amplifiers. They are used also for electrical heating resistors, safety blowout disks, thermocouples and crucibles. The tensile properties at elevated temperatures are important in many of these situations but data on the subject are limited. Creep data also are important, but will not be covered at this time. Scope and Conclusions Tensile tests were carried out at room temperature and elevated temperatures up to 1100" C. on previously well annealed samples of platinum. palladium and several of their important alloys with compositions shown in Table 1. The results are presented graphically in Figs. 1 to 4. The tensile strengths of platinum and the platinum-base alloys (with the exception of the 10 per cent rhodium-platinum alloy) at 1100" C. are from 16.6 to 18.8 per cent of the strengths of the same alloys (well annealed) at room temperature. The strength ratio of the 10 per cent rhodium-platinum alloy is 22.3 per cent, which is appreciably higher than that of the other materials tested. The tensile strengths of palladium and the palladium alloy at 1100" C. are from 10 to 11.2 per cent of the room-temperature values. The elongations of platinum and its alloys tend to increase at temperatures above 600" to 800" C., while the two samples of pure palladium show a maximum at 600" C.

Jan 1, 1938

By B. Amero, W. Petruk, D. R. Owens, D. R. Morris

Samples taken at different heights in the lead blast furnace of Brunswick Mining and Smelting corporation were studied to determine the phases present in order to interpret the reactions In the furnace. The main phases in the blast furnace feed are Pb3Ca2S13011, Zn ferrite (ZnFe204), and hardystonite (Ca2ZnSi207); rninor ones include lead and a Pb silicate. The temperature in the furnace varies from about 300°C at 4.2 m above the tuyeres to 1150°C at 1.1 m. There is no evidence of reactions in samples from points cooler than 800°C. Some reaction occurs between 950° and llOO°C and the lead sinter is nearly decomposed at about 1150°C. The first evidence of reaction was the decomposition of Pb silicate to lead and S102. At higher temperatures the Pb Ca2Si3011 decomposed to form lead and hardystonite (Ca2ZnS120rf. The Zn required for hardystonite was derived from the Zn ferrite which apparently re-equilibrated to a new Zn ferrite with less Zn. The decomposed sinter consists essentially of lead, hardystonite, wustite and a Zn ferrite with a low Zn content.

Jan 1, 1984

By Franklin R. Carpenter

Pyritic smelting, so-called, as practiced in the Black Hills is pyritic smelting only in the sense that Dr. John Percy uses the expression in his " Metallurgy of Silver," where he describes a process for smelting dry silver-ores in connection with iron pyrites, to form a regulus. The ores treated by this process in the Black Hills are very siliceous, averaging about 74 per cent. of silica, from 10 to 20 of iron oxide, 4 or 5 of alumina, and from 2 to 4 of lime. In 1889, while Dean of the South Dakota School of Mines, I took up the question of their smelting. There were neither copper- nor lead-ores in the Hills; hence pyrite and pyrrhotite, of which there are large deposits, were employed to form a regulus. This mixture of pyrite and pyrrhotite, besides being absolutely barren of gold and silver, carried an average of 30 per cent. of silica. The only basic material available as a flux for the great excess of silica in the ores and in the pyrite was a dolomitic limestone. Moreover, the local coke gave 24 per cent. of ash, 60 per cent. of which was silica—as unpromising a set of conditions as can well be imagined. We had before us the examples of Mr. W. Lawrence Austin, of this Institute, who had experimented at Toston, Montana,"

Jan 1, 1901

By J. J. Gilman

IT is well established that dislocations exist in crystals and account for crystal plasticity.' However, the origins of the dislocations are not clear. Among the means by which dislocations might originate are: a) through crystal growth accidents, b) by the collapse of condensed sheets of vacancies, or c) by stress-induced nucleation. Theoretical calculations' have indicated that the last means should require very high stresses in order to operate. The purpose of this paper is to show that the stresses around the tips of cracks are large enough to nucleate large numbers of dislocation loops. Specifically, it will be shown that (100) cleavage cracks in LiF crystals nucleate dislocations in regions of the crystals where dislocations did not exist previously. It is believed that the use of LiF for this investigation does not restrict the significance of the 1 results. In fact, it is believed that this complements and extends previous papers by the same author which dealt with metal crystals.10,14 The dislocations were detected by means of the etching techniques that were described in a previous paper by Gilman and Johnston.3 In that paper it

Jan 1, 1958

[Abrahamson, Guy C., (5'43) Lt., 0-880861, Hammer Field Fresno Calif. Adamec, LAW, (8'42) c/o Braden Copper Co., Rancagua, Chile. Adams, Karl S., (9'43) Univ. of New Hampshire, Durham, N. H. Agnilar, Roperto Q., (9'43) Texas College of Mines, El Paso Texas. Ainge, B'onald Farra, (943) Otago University, Dunedin, New Zealand. Akaran, Cevdet A,, (9'44) Pennsylvania State College, State College, Pa. Albala, Americo, (5'44) School of Mineral Industries, The Pennsylvania State College, State College, PA.]

Jan 1, 1946

By E. C. Dominguez, H. B. Scharf

The Sparrows Point plant of Bethlehem Steel Co., southeast of Baltimore, is the largest Bethlehem plant, with an annual rated capacity of 6.2 million ingot tons. There is considerable diversity of product, but a high percentage is sheet, tin plate, galvanized sheets, and rod and wire. The large amount of light-weight end product requires a number of pickling installations that necessarily consume large quantities of sulfuric acid. In the coking operations sulfuric acid is also consumed in recovery of ammonia as ammonium sulfate and in treatment of recovered light oil derivatives. Total sulfuric acid consumption in the plant is currently approaching 10,000 tons per month, of which 55 to 60 pct is required for pickling. In 1951 the acute sulfur shortage caused grave concern as to future sulfuric acid supply for the Sparrows Point plant. Raw materials for acid making were already at hand in the form of hydrogen sulfide and pyrites sufficient to produce nearly half the sulfuric acid required at that time. It was also known that the Bethlehem mining activities would produce additional pyrites in the future. Late in 1951 Bethlehem management decided to build a 250-ton sulfuric acid plant at Sparrows Point to utilize these raw materials. The plant was built and put in operation in May 1953. The steel plant has expanded considerably since 1951, and it is now necessary to operate the acid plant far over rated capacity in order to supply plant demand. Production of acid in 1954 amounted to 93,000 tons.

May 1, 1956

By Chester Lee

Introduction THE Atlin Mining District is in the northwest corner of the Province of British Columbia. Ruby Creek, where the operation to be described is situated, is 17 miles east of the town of Atlin and about 18 miles south of the south line of Yukon Territory (Fig. 1). Gold was discovered in the district in January, 1898, and the production to date from placer mines has been $4,518,000, according to the reports of the Minister of Mines for-the province. Geology The essential points in the regional geology are given in the following paragraphs. Long erosion produced a plane-like surface slightly above sea level with a few peaks and ridges.1 A gradual uplift followed and. erosion increased, the streams cut deeper, the cuts so made being afterward increased by glaciation. The ice straightened and planed the slopes of the main valleys and widened and lowered their floors, in some cases flooring the valleys with silt, sand, gravel, and clay. As the glaciers rapidly retreated, lakes were formed.

Jan 5, 1916

By Richard H. Sillitoe

Gold is an important byproduct and, locally, coproduct of porphyry copper deposits, and possesses potential for discovery as the major metal in porphyry deposits in either island arcs or Cordilleran belts. Tungsten and tin occur as major components of several potentially bulk-minable porphyry deposits, as well as being byproducts from the Climax porphyry molybdenum deposit. Whereas porphyry tin systems are localized in Cordilleran back-arc settings, their tungsten counterparts appear to span a range of geotectonic settings, from Cordilleran principal arcs through back arcs to rifts. Although silver is a common byproduct of porphyry cop- per deposits, it tends to be preferentially concentrated with lead and zinc on the fringes of all types of porphyry deposits and/or as late-stage superpositions; the latter situation could be of some interest in the higher parts of porphyry systems. As byproducts, rhenium, uranium, platinoids, and magnetite are exploited occasionally, and rutile and the rare metals, such as tantalum and niobium, merit consideration.

Jan 1, 1983

By G. M. T. Marshall

Plans to bring the Geco Mines property in Manitouwadge, Ont., into production began in 1954. At that time over 12 million tons of copper-zinc ore were indicated in a zone 2700 ft long. A concentrating plant was built to handle 3300 tpd of ore and a production shaft was sunk about 1500 ft. MINE LAYOUT Vertical attitude, width, rake, and competent country rock of a 4-million ton orebody west of the main diabase dike suggested a system of blasthole stopes, undercut with scram drifts connected by a transfer raise system to a crusher on the 1250-ft level and this system was employed. A 42-in. conveyor on this level transfers the ore about 1200 ft to a loading pocket at the No. 1 shaft. The system has a number of advantages: 1) Cost of tramming is eliminated. 2) Rate of extraction from any stope is controlled only by the scraping capacity of the scram. 3) Rate of extraction from the stoping area can be very rapid. Fast extraction makes it possible to cut mining costs for the following reasons: The number of stopes actively producing is kept to an economical minimum; the operating area is concentrated-manpower can be used more effectively; and active life of the stoping block is short, making ground support problems simpler and less costly.

Jan 8, 1959

By Frederick J. McGarry, Fred Moavenzadeh

An experimental investigation of the thermal and mechanical responses of rock materials to laser radiation is described. Specifically, the following three topics have been studied in detail: 1. Temperature measurements on thin discs subjected to laser radiation. 2. Strain measurements on thin discs subjected to laser radiation. 3. Observation and evaluation of cracking and spalling phenomena in constrained and unconstrained thin discs respectively, subjected to laser radiation. In conjunction with the experimental work done, use was made of a heat flow analysis and a stress analysis program developed for this purpose. It was possible to theoretically predict the thermal and mechanical responses of a rock specimen to laser radiation and then compare them with experimental observations. Good correlations were obtained.

Jan 1, 1971

By Samuel Gibson Frantz, G. W. Jarman

The purpose of this paper is to relate briefly the development of magnetic separation and its extension from the separation of iron into its present use in the nonmetallic field, to suggest possible future extensions of its field of usefulness and its possible cooperation with other separating methods. The engineering design of separating machines, and statistics as to the number of machines in operation, types, their location and production are outside the scope of this paper. Specific data will be given, however, on certain selected applications. A large part of human endeavor consists in separating one thing from another; the good from the bad, the desired from the undesired. In fact, a philosopher might plausibly claim that separating things into categories and choosing between them is the object of thought itself. In dealing with matter, separation is nowhere more inherently necessary to attain our objects than in mining and metallurgy. Both our desire and our ability to make separations are results of the physical differences between things. Gross separations such as removing ore from worthless rock or coal from slate are usually made visually and depend upon form and color, which are physical properties. When the desired and the undesired things are intimately mixed, however, it becomes impractical to select visually even if the individual particles are readily recognizable to the eye, and some automatic way of making the particles separate themselves on the basis of their own inherent differences in physical properties must be resorted to. Some of the physical properties which have been used as a basis of separation are: color, shape, hardness, size, density, elasticity, surface propertics (surface tension in contact with liquids, etc.), electrical conductivity, dielectric constant, and magnetic susceptibility. Differences in these properties are used in the following methods of separation: color sorting, sifting, settlement in air and in liquids, float-sink methods, flotation, electrostatic and magnetic separation.

Jan 1, 1932

Jan 1, 1932

Jan 1, 1883

By Gardner F. Williams

These mines are situated in Griqualand West, which is now a part of the Cape Colony. The town of Kimberley is in latitude 28o40' South, longitude 25o10' East, about 640 miles northeast of Cape Town and 450 miles from Port Elizabeth on the east coast. It is connected with these towns by a railroad, which has been completed during the present year. The mines are located in a desert country, resembling the desert portion of Arizona. The elevation above sea-level is about 4000 feet. The climate is exceedingly hot during the summer months. Diamond Deposits.—There are four large diamond-bearing deposits at Kimberley, all lying within a radius of one and one-half miles, having the De Beers mine as the center. These are named the " Kimberley," " De Beers," " Du Toit's Pan," and " Bultfontein " mines. There is, also, directly west of the Kimberley mine, a small deposit, called " St. Augustiue," which has been prospected only, and

Jan 1, 1887

By Shigeki Nishimura

INTRODUCTION In this gapes, the author will describes to development of Yubari New coal mine. The construction set about since October 1970, and commenced from June 1975 in winning. Especially, descrives to compare with the studies at planning stage, and the experiences at under construction. The problems for development are next four: 1) There were no outcrop of the coal bearing strata, but the development was instituted against the deep coal seam occurrence at 800 m below the surface. 2) In order to the coal seams occured the deep level from the surface, threr had very difficult problems, i.e. temperature, earth pressure, methane etc. The countermeasure to solved them, were foundation of the development. 3) The construction was afflict with the inundation in high pressure, due to cement grouting and excavating alternately, overcame the difficulties. 4) The construction was finished by the encourage of national investment, in spite of the enterprise was weaken constitution from the energy revolution since 1960's. OUT LINE OF YUBARI NEW COAL MINE Geography Situation. Ishikari coal field is situated the west side of the Hidaka mountains, where runs north to south at center of Hokkaido, northern district of Japan. It's width is 40km in east and west, and length is 110km in north and south.

Jan 1, 1976

By Frederick Tickell

PETROLEUM engineers are displaying considerable interest in those fundamental properties of matter and energy that control the phenomena of oil and gas production. The subject is a difficult one to investigate by laboratory experiments for two reasons: (1) it is impossible to reproduce in the laboratory the scale of forces and dimensions that exist in the underground reservoir; (2) if we attempt to scale down the dimensions we are unable to reduce all proportionally. It is as if we tried to construct a model blast furnace for the reduction of iron ore, and reduced all lineal dimensions. We should find that the interstices between the miniature chunks of ore would not .permit rapid transfer of gases, that combustion and heat transfer would not take place as in the full size furnace and that, in short, the contraption would not work. Just so, when we attempt to make a reduced scale oil field we find we must have, not only miniature reservoir and miniature wells, but "miniature" sand, oil, gas, etc. Much valuable work, however, has been done along these experimental lines and more will no doubt follow, but investigators should bear this point in mind and strive to attain dimensional homogeneity and dynamical similarity in order that their conclusions may be translated into terms applying to the oil reservoir. As Gibson says,1 "These conditions are attained when all terms of the physical equation have the same dimensions, . . . when all corresponding particles of the two systems trace out similar paths and when the velocities are such as to make all corresponding forces acting on two such particles in the same ratio. It is the purpose of this paper to discuss the mechanics of fluid movement as it pertains to the oil pool and to point out the complexity of the laws of fluid delivery under the conditions often found.

Jan 1, 1928