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By T. E. Schwarz

The publication of the report by Mr. F. L. Ransome1 was welcomed by many engineers who had mined in the heart of the San Juan country, braved its long and snowy winters, climbed its lofty peaks, run the gauntlet of its snow-slides, and studied its problems of geology, while making dividends for their English or American clients. This report helps one to understand why the bonanzas occurred, and why the inevitable " borrasca " presents itself where least expected. The Red Mountain district of Ouray county, a very productive section from 1884 to 1893, occupies considerable space in the report mentioned. The character of the ore-occurrence.

Jan 1, 1906

By M. E. Tyrrell, Alan H. Goode

The application of a simple, two-dimensional computer technique for evaluating rock burst potential in cut-and-fill stopes was investigated. The principal purpose of the study was to compare the effectiveness of high-modulus fill and destressing as aids in the control of rock bursts. Two conclusions that are probably of general applicability are drawn. First, high-modulus fill is ineffective as a means of increasing the mine stiffness and acts to control rock bursts only if it supports enough load to reduce substantially the stresses on the unmined vein material. Second, destressing is most effective if it is performed when the vein material is near the point of failure.

Jan 1, 1975

By F. M. Lyon, F. J. Chernosky

Research efforts have not developed techniques for the complete desulfurization of coal that is needed to reduce air pollution caused by burning coal and to reduce the sulfur in metallurgical coke. Sulfur in coal occurs in three forms and of these, the pyritic sulfur occurs as discrete mineral particles and, at least theoretically, should be subject to physical rejection. Pyrite occurring in hard rock mining is concentrated by froth flotation; therefore, the possibility of removal of pyrite from coal by flotation does exist. With this possibility in mind, the flotation and adsorption characteristics of ore and coal-pyrite were compared while using potassium ethyl xanthate as the collector.

Jan 1, 1973

By J. R. Barrett

Geotechnical techniques to evaluate conditions in underground metalliferous mines change through a mine's development from prefeasibility to remnant mining. The objectives of this paper are to determine the geotechnical requirements of typical underground metalliferous mining projects, to determine any shortfalls in conventional geotechnical techniques in satisfying these requirements, and to determine the costs of such investigations in proportion to the project expenditure. Finally, areas for future research and development are discussed. A group of over one hundred case history studies are examined to generate data on typical mining problems. The case studies include projects at most Australian underground metalliferous mining operations supplemented with case studies in Canada, Africa, Asia and Europe.

Jan 1, 1983

Feb. 5. Society for Applied Spectroscopy, 6 pm, supper, Tosca's; 8 pm, meeting, Socony-Vacuum Training Center, 63 Park Row, New York. Feb. 6, AIME, Chicago Section, Chicago Bar Assn., 29 S. La Salle St., Chicago. Feb. 18-21, AIME, annual meeting, Hotel Statler, New York. Feb. 19, Michigan College of Mining and Technology, alumni reunion, Skytop Room, Hotel Statler, New York. Feb. 21, AIME, Utah Section, Newhouse Hotel, Salt Lake City. Feb. 28, Bituminous Coal Research, Inc., annual meeting, Edgewater Beach Hotel, Chicago. Mar. 3-7, ASTM, spring meeting and committee week, Hotel Statler, Cleveland. Mar. 5, AIME, Chicago Section, Ladies' Night, Chicago.

Jan 1, 1952

By Mungo Park, C. Baring Horwood

This paper is intended, in the light of recent investigations, to call attention to some of the essential features of good practice in sampling and mine-valuation. Mine-sampling may be divided broadly into two classes: (1) development-sampling and cornputatioll of ore-reserves; and, (2) stope-sampling and estimation of stope-values. Development-Sampling. It is with development-sampling only that this paper deals— the term development being taken to mean the opening-up of a mine by cross-cuts, drives, connections, etc., preparatory to actual extraction of the ore for milling. In development-sampling the work of the sampler and the consequent estima-

Jan 1, 1909

By Alvin L. Langstaff, Harold D. Raymond

The design of entry systems and mining panels in room-and-pillar oil shale mines seeks to optimize extraction while ensuring both short- and long-term stability of mine openings. Important criteria for optimization include the definition of allowable roof spans and minimum pillar dimensions. Factors considered pertinent to the design of roof spans and pillars are discussed in this paper. They include, but are not limited to, physical properties and grade of the oil shale, depth of burial, presence and frequency of partings and joints and adverse effects of blasting. Also discussed briefly are some of the ventilation and production considerations in mine design.

Jan 1, 1984

By Shuichiro Okada

The Tamano Smelter, which is engaged in copper smelting by Flash Smelting Furnace with Furnace Electrodes (FSFE) has since 1982 revised its computer and associated control system for the purpose of greater energy savings, stable operation, and strict environmental control. This revision is bringing about a remarkable cost savings through greater reduction in energy consumption. This paper describes in detail the following: (a) outline of renewed process computer system, (b) approach to prediction model of FSFE based on data collection and its analysis, (c) actual examples of process control by using its prediction model, (d) future trends in the computer control at Tamano Smelter.

Jan 1, 1984

By Toyohiko Hirota, Fukuo Itoh

Oil and natural gas aside, sea floor mineral resources currently being exploited in Japan are offshore sand and gravel and deep-sea manganese nodules. The mining of sand and gravel has already started. With regard to manganese nodules, the geophysical investigation and the study of the mining method are also underway. This report outlines the activity of a few Japanese firms, the Deep Ocean Minerals Association formed by some 30 private firms, Government agencies, a public corporation and two government research institutes. Researches on new exploration instruments, properties of deep-sea sediments and the mining method currently conducted by the National Research Institute for Pollution and Resources are described in detail.

Jan 1, 1976

By E. Gilpin

Any estimate of the economic mineral value of an unvisited district is to the mining engineer largely a comparative one. If he knows that certain minerals characterize any given geological horizon he naturally draws upon his experience of the same ores as met by him cinder similar geological conditions. And if he has not had the personal experience, the investigation of the geology of a similar district as given in a trustworthy report enables him to lay a fair basis for conclusions. In a general way these conclusions are of value, and while they pronounce on the possible mineral fecundity of a given district, they

Jan 1, 1890

By H. L. Monroe

Meramec Mining Co., owned 50% by St. Joseph Lead Co. and 50% by Bethlehem Steel Corp., is engaged in mining, concentrating and pelletizing iron ore from the Pea Ridge Mine which is located about 75 miles southwest of St. Louis. The Pea Ridge orebody lies under some 1300 ft of limestone, dolomite, shale, and sandstone. It runs from east to west for about 1/2 mile and varies in width up to a maximum of around 600 ft. The orebody dips about 80" S. The ore is high grade magnetite with some local zones of specular hematite. The Precambrian country rock is rhyolite porphyry.

Jan 12, 1965

By A. A. Dor

Out of nine new major iron ore concentrators put in operation during the last three years, or expected to be commissioned in 1968, seven incorporate primary grinding mills and have a total design capacity of 13,150,000 ltpy of pellets, while only two include conventional rod and ball mill grinding circuits for a total design capacity of about 6,100,000 ltpy (Table I). This evolution in the application of primary grinding to hard, fine grained magnetite ores represents an important development in the technology of mineral processing. It has been the outcome of comprehensive testwork in the laboratory and in pilot plants.

Jan 11, 1968

By E. A. Khopunov, V. I. Revnivtsev

The process of triboelectric separation from the point of view of its potential for selective separation of various mineral particles can be described as "dry flotation." Large scale practical applications of this technique are limited because suitable models which can describe contact charging of mineral particles have not been developed. Among the various concepts a promising one is an attempt to change development in dielectric minerals within the limits of contact phenomenon in semiconductors. Experimental investigations reported in this paper indicate that the charge development is mainly a result of contact electrification of dielectric minerals characterized by "donor" and "acceptor" type energy spectra due to lattice defects.

Jan 1, 1980

By A. J. Lynch, N. W. Johnson, D. J. McKee

The behavior of nonsulfide gangue in chalcopyrite flotation circuits has been investigated. Plant and laboratory tests were conducted on five different ores. Linear relationships between the recovery rates of free nonsulfide gangue and water were observed. From pilot plant tests, there was evidence that the linear relationship was actually a linear approximation to a parabolic relationship. There was evidence that free nonsulfide gangue is transported from the pulp to the froth in the water and that the gangue is subjected to hydraulic classification in the froth column. A classification matrix has been proposed to define this behavior. This matrix is suitable for inclusion in a mathematical model of the process.

Jan 1, 1975

By E. H. Ahrens

This paper deals with the responsibilities of an operating geologists and the relationship of operations to exploration. It should be of interest to those soon to enter the profession, those new to mining geology and as a review to more experienced geologists. Subjects discussed include detailed geologic mapping, sampling, core logging, assaying, selection of proper map scale, posting geological and assay data, section preparation, identification of ore controls, delineation of development drill targets and geologic hazards, models and the very important topic of salesmanship. Methods and ideas, proven valid in vein, pyrometasomatic replacement and porphyry copper deposits are presented. Hopefully, these will smooth the path for new members of our profession.

Jan 1, 1984

On July 25, the first copper ore From American Smelting & Refining Co.'s Mission open pit nine was sent into the new 15,000-tpd concentrator : three clays later, the first rail cars containing the Mission concentrate were sent north to the smelter at Hayden, Ariz. Thus two y,ears after stripping was started, Asarco's new mine, located south of Tucson. went on stream several months ahead of schedule. The plant, designed and constructed by Western Knapp Engineering Co., is expected to be operating at full capacity about September 1. with present plans calling for the copper concentrate from Mission to be shipped to Asarco's smelters at Hayden and El Paso.

Jan 9, 1961

By S. L. Crouch

The application of a simple, two-dimensional computer technique for evaluating rock burst potential in cut-and-fill stopes was investigated. The principal purpose of the study was to compare the effectiveness of high-modulus fill and destressing as aids in the control of rock bursts. Two conclusions that are probably of general applicability are drawn. First, high-modulus fill is ineffective as a means of increasing the mine stiffness and acts to control rock bursts only if it supports enough load to reduce substantially the stresses on the unmined vein material. Second, destressing is most effective if it is performed when the vein material is near the point of failure.

Jan 1, 1975

By J. B. Evans

Maintaining overall optimum profitability at a mine site necessitates constant reassessment of operating strategies. In essence, each strategy is a particular combination of envisaged capital expenditure, income flow and elapsed time. Selecting a strategy, based on profita¬bility potential requires each contemplated strategy being subjected to discounted cash flow analysis; even with a computer such analysis can be cumbersome. The chapter discusses a 'shortcut' technique which assigns profitability rankings to alternate strategies and iden¬tifies those aspects of a. strategy which impact heavily on profitabil¬ity. This technique can yield quick assessments of sufficient accuracy for many operating strategy decisions. taken on site at on-going mines.

Jan 1, 1978

By M. D. Cooper

Production of both anthracite and bituminous coal in 1954 was about 16 pct below 1953. Estimates on Dec. 1, 1954, indicated 27 million tons of anthracite and 385 million tons of bituminous. Decline in production was due principally to lower demand by the steel industry and the railroads, although competition from other fuels also affected coal. The year was notable for vigorous effort by the coal industry to promote the use of its product. A Cabinet Committee on Energy Supplies and Resources Policy and an Interdepartmental Committee on the Soft Coal Industry were set up by the Administration in Washington. A Governors' Fuel Conference was also organized.

Jan 3, 1955

By B. K. Parekh, W. M. Goldberger

A novel process is proposed for continuous removal of ash and unreacted solids which become suspended in the oils obtained during coal liquefaction. The proposed method uses water in direct contact with the oil under conditions which cause the suspended residue solids to transfer from the oil to the water phase. Separation of the phases yields a product oil essentially free of suspended solids. The water is cooled, clarified or filtered by conventional low-cost systems, and recirculated. The paper describes experimental work leading to development of the novel concept and includes the result of batch experiments that establish the feasibility of the process.

Jan 1, 1980