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By R. E. Lindstrom

Electrooxidation techniques were investigated on a bench scale by the Bureau of Mines to determine the applicability of the process for extracting molybdenum and rhenium from low-grade molybdenite concentrates. Parameters affecting the extraction, such as pulp density, power consumption, reagent requirements for pH control, and electrolytic cell configuration, were studied. Molybdenum and rhenium extractions of 98 to 99 percent were achieved from several concentrates containing 4.76 to 28.6 percent molybdenum and 180 ppm to 1,000 ppm rhenium. Optimum results were obtained by maintaining pH values between 5.5 and 7.0 during electrolysis and allowing the final pH to rise to about 8.2. Reagent consumption was 4 to 6 pounds of sodium carbonate per pound of molybdenum extracted. The power consumption declined from a range of 12 to 25 kilowatt hours per pound of molybdenum extracted with immersion electrodes to 9.7 kilowatt hours with a bipolar flow-through cell; however, molybdenum extraction was independent of cell configuration.

Jan 1, 1973

By Karl J. C. Harries

"The following is an outline or check sheet of some things that might be looked at when considering the concept of a royalty or royalty provisions. It is not intended as a guide to what is right or wrong (that is for the parties to decide). It does not replace the discussions in this work and is not intended to be a complete or exhaustive compilation of matters to be considered. It presumes that you are familiar with the basic concepts of royalties and has been included as an aide memoire only. Use it as such, with caution and common sense, and amend it to suit your needs. Remember also that brevity can result in inaccuracy or imprecision. This is a danger in many points below.The section references are for the sections where the matter is the main subject of the section – see the index for other sections.Royalty TypesNet Proceeds [§§ 5.8.; 11.4.]• No accepted or understood meaning within industry.• Literal meaning, if not defined, would imply “net operating profit”.• Often defined as net profit with revenue base of proceeds from sale of product.• Should not be used without detailed and clear definition. Net Operating Profit [§§ 5.8.; 11.4. – referred to only]• Net profit without recoupment of pre-production expenditures.• Revenue base: usually proceeds from sale of product.• Operating costs deductible.• Some reserves may be permitted.• Recoupment of some post-production capital expenditures may be permitted.• Not often seen as basis for royalties in Canada."

Jan 1, 2003

By C. P. Mangelsdorf

Introduction The use of frequency of vibration measurements to determine tension has long been accepted by industries that use electrical or stranded cables of wire ropes in their operations. In contemplating how to determine the tension in chords of a roof truss, it seems almost inevitable that a similar approach should be investigated even though there are some important dissimilarities in physical behavior between a chord of a rod-type Birmingham truss and a stretched wire rope. While the dominant feature of both types of behavior is the existence of tension, the bending resistance of the vibrating truss chord cannot be ignored. And it is common to have attached to the chord, pieces of hardware (turnbuckles, extension sleeves, wedge boxes) that represent concentrations of mass not usually found in a vibrating wire rope. Analytical solutions to the problem of vibrating wires or beams can be found in the literature on vibrations (Timoshensko, 1955; Den Hartog, 1956). But in every case, at least one of the ingredients of the vibrating truss chord is missing. The presence of axial tension, or bending resistance, of concentrated masses and of end conditions peculiar to truss chords is a combination that appears not to have been dealt with before, although the techniques for dealing with it are commonly known. The purpose of this note is to report the results of a project to measure and calibrate such frequencies. The work was conducted by the University of Pittsburgh under the sponsorship of the US Bureau of Mines. Field observations Tests were conducted on 24 different truss installations. The first 18 trusses were installed in shale roofs above Kentucky No. 9 seam and Illinois No. 6 seam. The remaining six were placed against the competent sandstone over the Pocahontas No. 3 seam in West Virginia. Chord tension was determined by two electrical resistance strain gages, in series, applied diametrically opposite to one another on the rod before tensioning. Due to the combined effects of inexact gage placement, rod bending and residual torsion in the chord due to tightening, errors in tension as high as 1780 N (400 lb) were reasonably possible. Due to faulty soldering or damage, three of the first 18 trusses and one of the final six were rendered completely unreliable. In addition to strain, the first natural frequency of vibration was observed to the nearest 0.1 Hz. Dimensions recorded included the span between contact points at the bearing blocks (Fig. 1) and the locations and amount of excess rod and rod gap at the wedge box and turnbuckle, respectively.

Jan 9, 1985

By M. Arias

"An attractive foreign investment legislation, an anti-mining framework in the jurisdiction where a head office is located, the geographical location of the mineral resources, a country that offers the technology needed by the industry for its operations -- these are some of the many factors that make mining and mineral exploration a global business. It is precisely in the complexity of this new era of globalization and market environment, that sustainability initiatives are challenged. Responsible management of mineral exploration and mining is no longer defined by the use of efficient technology and resource management. Sustainability is not only a report compliance exercise or a green revolution. Sustainability is like any business, a long term profitable proposition. This new approach encompasses four pillars: social, economic, environment, and culture. This new approach connects humans and corporations; it is the way to engage, respect and improve relations with the people with whom we work and our neighbours."

Jan 1, 2011

By Khosrow Bakhtar

A series of nineteen shear tests were performed on fractures 1 m2 in area, generated in blocks of sandstone, granite, tuff, hydro- stone and concrete. The tests were conducted under quasi-static and dynamic loading conditions. A vertical stress assisted fracturing technique was developed to create the fractures through the large test blocks. Prior to testing, the fractured surface of each block was characterized using the Barton JRC-JCS concept. The results of characterization were used to generate the peak strength envelope for each fractured surface. Attempts were made to model the stress path based on the classical transformation equations which assumes a theoretical plane, elastic isotropic properties, and therefore no slip. However, this approach gave rise to a stress path passing above the strength envelope which is clearly unacceptable. The results of the experimental investigations indicated that actual stress path is affected by the dilatancy due to fracture roughness, as well as by the side friction imposed by the boundary conditions. By introducing the corrections due to the dilation and boundary conditions into the stress transformation equation, the fully corrected stress paths for predicting the strength of fractured blocks were obtained.

Jan 1, 1984

First Session BRASS Wednesday, A.M., Nov. 29 Co-Chairmen: CARTER S. COLE, Staff Engineer, A.S.T.M. E. A. ANDERSON, Chief of Metals Section, Research Div., New Jersey Zinc Co. (of Pa.) Second Session BRASS Wednesday, P.M., Nov. 29 Co-Chairmen: D. K. CRAMPTON, Director of Research, Chase Brass and Copper Co., Inc. A. W. TRACY, Metallurgist, The American Brass Co. Dinner and Technical Session Wednesday Evening, Nov. 29 Toastmaster: N. L. MOCHEL, Manager Metallurgical Engineering, Westinghouse Electric Corp. Talk on "How Do Things Look Today and For the Future" RALPH KELLY, President, Baldwin Locomotive Works Technical Paper on Stress-Corrosion Cracking E. H. Dix, JR., Assistant Director of Research and Chief Metallurgist, Aluminum Company of America Third Session BRASS Thursday, A.M., Nov. 30 Co-Chairmen: W. B. PRICE, Director of Research, Scovill Manufacturing Co. A. L. JAMIESON, Associate Metallurgist, Frankford Arsenal First Session LIGHT METALS Thursday, P.M., Nov. 30 Co-Chairmen: L. L. WYMAN, Metallurgist, General Electric Co. M. A. HUNTER, Professor of Metallurgical Engineering and Head, Dept. of Metallurgical Engineering, Rensselaer Polytechnic Institute Second Session LIGHT METALS Thursday Evening, Nov. 30 Co-Chairmen: R. T. WOOD, Chief Metallurgist, American Magnesium Corp. J. D. HANAWALT, Director, Metallurgical Dept., Dow Chemical Co. First Session STEEL Friday A.M., Dec. I Co-Chairmen: H. S. RAWDON, Chief, Division of Metallurgy, National Bureau of Standards A. L. FEILD, Director of Research, Rustless Iron and Steel Corp. First Session MISCELLANEOUS METALS Friday P.M., Dec. I Co-Chairmen: E. A. ANDERSON, Chief of Metals Section, Research Div., New Jersey Zinc Co. (of Pa.) CARTER S. COLE, Staff Engineer, A.S.T.M.

Jan 1, 1945

By Hal McVey

Introduction The role of marketing in the minerals and mining industry takes on different degrees of importance depending on the commodity, but nowhere are sales and marketing more important than in industrial minerals. This article compares industrial minerals marketing with the marketing of other mining and mineral products. Marketing in Mining Some broad generalizations on the marketing of industrial minerals in relation to other mineral products can be made without getting bogged down with exceptions to generalizations. Two totally different areas of mineral production are crude oil and natural gas, and metals, including ores and concentrates. Although these commodities are the basis for two completely different industries, they share two things in common from a marketing standpoint: • Their value per unit volume is usually high enough so that they can be transported great distances. • Their specifications are readily definable and, therefore, the quality of a standard product from a production run can be communicated by stating certain chemical and physical features. This permits sales to be consummated by telephone, telex, and letter, without the need to pretest the products under use conditions. In regard to the first item, industrial minerals, as opposed to oil, gas, and metals, are in most instances site specific. Location of the point of production in relation to the point of use is of paramount importance based on a generally lower unit to volume value. This means that transportation is a major factor, with the cost of getting the mineral to market commonly exceeding its f.o.b. value. Coal marketing has many characteristics in common with industrial minerals. Coal sales can es-

Jan 11, 1983

By Joshua Hoffman, Catherine Johnson, Braden Lusk

Blasting conducted in surface coal mining operations in the Appalachian region consumes a significant amount of blasting agents. Emission of oxides of nitrogen (NOx) from these operations potentially represents an environmental challenge. This paper presents work conducted to quantify NOx output from the detonation of blasting agents common to surface blasting operations in surface coal mines. Annual ANFO and emulsion consumption data was collected from an operational surface coal mine located in West Virginia. It is known that many factors contribute to the types of gaseous byproducts released from the detonation of explosives. These factors include but are not limited to: fuel to oxygenator ratio, degree of confinement, and contamination. While, past research has been conducted to study the relationships these factors play on the release of NOx, these findings do not agree with one another. The annual explosive consumption values from the West Virginian mine were applied to NOx emission conversion factors in published literature. This lead to a range of NOx emissions from 95 to 914 tons in a year. Given the wide range of NOx production the utility of this information is suspect. The EPA recognizes a standard factor of 17 lbs (NOx)/ton (ANFO) however this factor is based on chemical composition and does not address contamination, confinement, or AN to FO ratio. This factor when applied to the West Virginia Mine's explosive consumption produced a value of 215 tons of NOx. There is a lack of information on NOx emission from emulsion type explosives. The work presented in this paper can be used by blasting professionals to quantify NOx emissions and guide future work for producing better predictor factors.

Jan 1, 2014

By Clayton M. Rumsey

No producing or developing mines nor known mineral resources are in the Lower Saline Valley Wilderness Study Area. The inactive Bonanza Prospect has low potential for copper-gold-silver resources. Stone and sand and gravel deposits in the WSA do not constitute mineral resources because transportation costs to major markets are prohibitive. INTRODUCTION The Lower Saline Valley Wilderness Study Area (WSA) covers 2,241 acres in southeast California adjacent to and west of Death Valley National Monument (fig. 1). Access to the WSA is by the Saline Valley gravel road 28 mi northerly from its junction with State Highway 190. The junction is about 35 mi southeast of Lone Pine, CA. The WSA is characterized by moderate to steep, sparsely-vegetated slopes; elevation ranges from about 1,800 ft to 3,560 ft.

Jan 1, 1984

By A. M. Hill

"This is an account of the expansion of Texasgulf's Timmins concentrator by the building of a fourth circuit.The original capacity of the mine and concentrator was 3.6 million tons per year of ore. In 1974, Texasgulf decided to increase that capacity by about one third to 4.8 million tons per year. It was planned that the increased capacity would be available by mid-1978.The expansion involved work at the rninesite, increased railroad capacity, and a new circuit in the concentrator, and it is the concentrator expansion which is described here.In 1974, the minesite drew its ore from the open pit. The pit was being phased out and was to be replaced by No. 1 mine. To allow for the expansion, a second mine was required. The railroad was capable of handling 18 car trains. Its capacity had to be increased to 27 cars per train and this, in turn, required two new locomotives. Each of these alone cost half a million dollars.The concentrator building in 1974 contained the concentrating equipment and miscellaneous services (such as machine shop, warehouse, analytical lab). The grinding and flotation sections were divided into three circuits ('A', 'B', & 'C'). 'A' and 'B' circuits treated copper-zinc ore and 'C' circuit treated the much more difficult copperzinc- lead ore. This 'C' circuit had been modified over the years to implement improvements in the metallurgy."

Jan 1, 1979

To develop and design a bit that will rapidly drill smooth and precise instrumentation holes in soft rock. Approach Use a one-piece bit made by combining a drag bit and a diamond bit. Because a smooth-walled borehole with a precise diameter is needed for borehole pressure cells (BPC) and other borehole instruments, a diamond bit is usually used. However, diamond bit drilling is slow, and the bit will tend to bind when squeezing ground is encountered. On the other hand, the drag bit will cut faster, but the walls of the drill hole will be rough and the diameter will not be as precise. The combination will provide a bit which penetrates as rapidly as a drag bit, but retains the smooth-wall and precise borehole diameter of a diamond bit. How It Works A three-foot-length of EW-size drill rod is centered in a diamond bit by welding it to three equally-positioned spacers at each end of the bit. A drag bit is attached to the EW rod with a standard EW-to-drag bit adapter as shown in the diagram. Three equally-spaced diamond inserts are set to the desired hole size and welded to the diamond bit barrel behind the crown. These inserts increase the smoothness and precision of the hole by cut-ting away any hole closure. Three equally-spaced shims are set approximately 0.020-inch under the overall insert diameter size and welded to the rear of the diamond bit barrel. The combination bit should be used on a diamond drill with either water, mist or air as the coolant.

Jan 1, 1982

To concentrate coarse mica particles using a dry beneficiation technique. Approach Concentrate coarse, II berated mica particles using a Bureau-designed system of crushers, screens, and a two-stage zigzag air classifier. How It Works Because mica has a flat plate-like crystalline structure, mica particles are significantly lighter than blocky gangue particles of the same size fraction. Thus an air classification technique can separate the flat, light mica particles from the heavier gangue particles. The ore, which Is first run through a standard jaw crusher, a roll crusher, and a hammer mill to liberate the mica, enters the rougher Zig-zag section through a rotating air lock. See photograph and diagram of a 2-stage air classifier. Airflow through the classifier can be varied according to the size of the particles being separated. The gangue material falls through the airstream of the rougher zigzag section and is discarded as tailings. The mica flakes are carried by the air-stream to the cyclone shown on the right side of the diagram, where they are collected. This rougher mica concentrate is fed to the cleaner zigzag section through another rotating air lock. The mica particles are again carried by the airstream but they are now collected In the cyclone on the left side. The cleaner concentrate leaves the left-side cyclone through a third rotating air lock and is rescreened to remove under-size material missed by the first screening. The final product of this pneumatic process is generally a high-grade mica concentrate. A generalized flow diagram for the pneumatic concentration method Is shown In the second diagram.

Jan 1, 1981

By G. F. Loughlin

The subject of this lecture might well have been assigned to an economist or banker rather than to a geologist, but, as it was deliberately assigned to me, it is to be treated from a geologist's viewpoint. The term precious metals ordinarily includes the platinum group as well as gold and silver. Platinum, like silver, has had a great decline in price during the last few years, but has not been a medium of exchange and therefore has aroused comparatively little comment. Its relation to price level is like that of commodities in general, and will be dismissed without further comment. Of the two precious metals used as mediums of exchange gold, because of its adoption as the basis of most monetary systems and because of its threatened shortage in the near future; has been a subject of general concern to governments, financiers, and economists; silver, on the other hand, which has flooded the market of late has brought forth cries for help, direct or indirect, from producers and to a less extent from the largest users, especially China, whose purchasing power has been greatly curtailed, but it fails to arouse the interest that gold does. Many predictions have been made by economists, bankers, and others regarding future supply of gold and its effect on prices but the differences among these predictions are about as many as the number of prophets. Since gold is the standard by which the value of commodities as a whole is to be measured, it would seem that the greater the ratio of gold supply to commodities the higher the price level and vice

Jan 1, 1932

By J. C. Williams, M. J. Blackburn

MANY aspects of the formation of the metastable w phase in titanium-transition metal alloys have been described in several recent papers.1-4 These papers have reviewed earlier work on the w phase and have further defined most of the important features related to the formation of this phase, e.g-., its crystal structure, composition, and morphology. There are, however, several important points regarding formation of the w phase in titanium alloys which have been described in less detail. Two of these are the relationship between lattice misfit and w phase morphology and the influence of lattice misfit on the mode of formation of the equilibrium a phase. In this communi- cation we will present transmission electron microscopy results relevant to these two points. The alloys used in this study were prepared by non-consumable electrode arc melting, each 30-g button being remelted a minimum of twelve times. The alloy compositions we have studied are listed in Table I. Thin foils were prepared using standard techniques described elsewhere. Two distinct c' phase morphologies have been reported in earlier papers. The phase is ellipsoidal in the Ti-Mo3 and Ti-Nbl system and cubical in the Ti-V3 system. Results of the present study show that the w phase is also cubical in Ti-Mn, Ti-Fe, and Ti-Cr alloys as illustrated in Fig. l(b) to (d). Fig. l(a) shows the ellipsoidal morphology in Ti-MO3 for comparison purposes. It was suggested in an earlier paper3 that the w phase morphology may be controlled by the lat-

Jan 1, 1970

By C. H. G. Bushell

The author maintains that selectivity in flotation depends in part on differences in rates of flotation. The rate of flotation should be directly proportional to the frequency of particle-bubble collisions. In this paper, it is suggested that floatable particles of the mineral must be distinguished from nonfloatable particles. Success in flotation is entirely a matter of selectivity. All minerals can be made to float. The problem is to make one mineral float and leave the others in the tails. For a typical ore, with all minerals naturally hydro-philic, a collector which is adsorbed by only one mineral and not at all by the others would give perfect separations. The hydrophobic, collector-coated mineral would separate cleanly from the remaining minerals. In practice, no such highly specific reagents are known. All standard collectors adsorb on most minerals to some extent, and selectivity then becomes a matter of extent of adsorption rather than adsorption on some minerals and not on others. Flotation is therefore a compromise process: if enough reagent is used to float all the desired mineral, the concentrate will be low grade; conversely, high grade concentrates can be attained only at low recovery. With many minerals coated with collector to varying degrees, selectivity appears to depend in part on each mineral floating at a different rate. The study of flotation kinetics is therefore a basic requirement to quantitative understanding of the process. REVIEW OF PREVIOUS THEORIES Before a particle enters the froth it must strike a bubble and adhere to it. Flotation rate will therefore depend on the number of particle-bubble collisions

Jan 1, 1962

By C. O. Brawner

Geotechnical theory is reasonably well developed to evaluate the stability of rock slopes for surface mining projects. It is recognized widely that structural geology, groundwater pressures and seepage, and blasting are key factors that influence the stability of such slopes. However, our capabilities to model the structural geology, to determine rock strength along discontinuities and to model groundwater pressures and profiles are still very approximate. Plus, practical experience of the rock mechanics engineer is one of the most important inputs to the design of open pit mine slopes. To emphasize the use of practical experience, a number of case examples are reviewed here to illustrate key factors that must be evaluated. These case examples comprise a continuation of other examples presented in the Jackling lecture to the SME in 1986 by the author (Brawner, 1986). Example no. 1 In situations where the orientation of geologic discontinuities will not influence rock slope stability, extremely steep slopes can be developed, providing blasting and groundwater are controlled adequately. An excellent example of this condition is the Republic Pit of Cleveland Cliffs in Michigan. The rock slope in Fig. 1 isover400fthigh with a face angle of approximately 80". The rock is hard and massive, and blasting was carefully controlled. The original design of this slope was at45", a standard design angle at that time. The competency of the rock and the lack of critical geologic structure subsequently was recognized, and the much steeper slope angle was developed successfully. The rock proved to be so competent and the slope sufficiently stable that an underground crusher station was developed with entrance and exit tunnels excavated at the toe of the steep wall.

Jan 1, 1991

By H. L. Bourne

The sand dunes which line the east shore of Lake Michigan resulted after the last, or Wisconsin, glacial period in Michigan. Melt-water streams carried vast quantities of glacial debris to the near shore areas of predecessors to Lake Michigan. As the lake levels receded, these vast quantities of sand were exposed to the prevailing westerly winds, which was the last major process that acted upon the sand and resulted in the formation of the dunes. 1 These dunes are one of the significant natural resources within the state. Michigan dune sands supply about 90% of the foundry sand used in the automotive industry, and 40% of the foundry sand used 2 for all purposes within the United States. The deposits owe their importance to the following factors: grain size distribution, grain shape, mineral composition and location with respect to the foundry sand market. In spite of their economic significance these I deposits are in jeopardy through legislative preemption.

Jan 1, 1975

By Ta M. Li

Expanded mine-mill capacity and greater operating flexibility are part of the dramatic changes taking place in the Tennessee mining operations of Asarco, Inc. Climaxed by the recent start-up of the $6.3 million Young mill in September 1975, Asarco has pushed Tennessee back into number one position as the leading zinc mining state. Furthermore, start-up of the Young mill is expected to insure a much-needed and continuing domestic zinc supply, at a time when US mines can only supply one-half of 1975 domestic consumption.

Jan 5, 1976

By P. H. Davenport

"The ore-element patterns in regional lake sediment geochemical survey data from four areas of Newfoundland containing granite-related mineralization reveal characteristics which can be used to identify mineralized granitoids. The St. Lawrence Granite with its fluorite deposits, the Ackley Granite with molybdenite mineralization, the Grey River tungsten lodes and the newly discovered Mo- W mineralization at Granite Lake, Central Newfoundland, have all been included in the regional lake sediment geochemical surveys, which now cover about 90,000 km2 of the Island of Newfoundland. The lake sediments over these mineralized granites show diagnostically high values of Mo, F, Pb, Zn and, in three of the four cases, U, together with locally high Ag and Cu values. Furthermore, these ore-metals display a distinctive zoning pattern about the intrusives, which can be related to the classical ore-metal zoning patterns developed about many types of mineralized granitoids.IntroductionGranitoids in Eastern Canada are receiving renewed interest as potential hosts of tin, tungsten, uranium and related mineralization. Although a number of mineral deposits and showings have been known from a few granites (sensu lato) in the region for many years, granites had generally received little attention as potential hosts of metallic mineralization until the recent resurgence in interest in the mineral potential of these rocks. In Newfoundland, where granitoid rocks underlie about 30070 of the land area, petrologic data are available from some granites, particularly those in eastern Newfoundland (Strong et al., 1974; Strong, 1980), but in southern and southwestern Newfoundland the data base is sparse, and indeed in many cases individual plutons are not delineated on the geological maps of the area . Most of the available data on Newfoundland graniotolds have been summarized by Strong (1980), who gives a general assessment of their mineral potential by comparing their physical, mineralogical and petrochemical attributes with mineralized granites elsewhere in the world."

Jan 1, 1982

By M. Baeyertr

Since 1915 many papers and books have covered industrial applications of X-rays from various angles. Two of the more recent are a paper by Fink and Archer, which describes in detail the technique of radiography, and a paper by Clark2, which embraces the whole field of X-ray metallogmphy. This paper, therefore, is confined to work of the X-ray Laboratory of the Western Electric Co., which naturally divides into two categories: radiography and diffraction patterns of various types. Radiography Radiography is the field in which the application of X-rays has had most general appeal among the industries which produce or use metals and alloys. Equipment permitting the examination of heavy sections of metals less permeable than aluminum or other light alloys requires apparatus capable of generating hard X-rays over a considerable period of time. The equipment used in the work presented in this paper is practically identical with that described by Fink and Archer in their paper on radiography in industry and is easily capable of penetrating 1/8 in. of lead. Radiography is used in two major groups of problems: (1) in the development of cquipment and tools and (2) in studies of materials. So far there has been no instance in which the use of radiography for routine inspection is justified. This is partly due to the fact that the manufacture of telephone apparatus involves the production of many identical parts by standardized procedures and equipment that has had development and trial before being put on a regular production basis. It is during this stage of development of equipment and tools that radiography has been used to particular advantage.

Jan 1, 1931