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By Fred T. Williams

The Park City mining-district is distinctively a camp of few properties, 5,000 acres, or one-third of the entire district, being under the management of but three companies. As a rule, the ore-bodies lie deep, with no outcrop, except where erosion has formed the deeper canyons and gulches. Ontario canyon exposed the famous Ontario ledge, and Woodside gulch showed the first ore of the Silver King Coalition mine. The Quincy ore-bodies were first brought to light in upper Empire canyon, and Thaynes canyon was instrumental in aiding the prospector during the early days of the camp. There are 22 shafts which have reached a depth of at least 500 ft., ten a depth of 1,000 ft., five a depth of 1,300 ft., and two a depth of 2,000 ft. The amount of lateral development has been proportiorlally extensive, including six long tunnels, four of which are in 3 miles, with a fifth now being driven. The Ontario lower drain-tunnel is now more than 4 miles long. The formations are sedimentary, dipping about 30° NW. and N., and traversed by many fissures, dikes, and faults. The principal ore-bodies are found. associated either with the contact of the basal Ontario quartzite and the overlying limes, or on a quartzite stratum within the limes, or in the fissures, or along some of the porphyry dikes. The district covers the intersection of the Uintah and Wasatch ranges, which explains the existence of large folds and faults, and fissures of great length, width, and depth. In a general way, the geology of the district consists of a basal quartzite dome, which has been exposed by erosion at the Ontario property. The Ontario fissure lies entirely within this formation. Flanking this dome on the west, north, and east lie

Jan 1, 1912

By R. E. Collins, Paul B. Crawford

Mathematical equations have been derived to show the effect of the slippage phenomomenon (Klinkenberg effect) on unsteady-state gas flow through porous media. The assumption is made that the slippage may be represented by an equation of the type It is pointed out that most of the existing data on unsteady gas flow may be corrected for slippage by a simple change in definition of the dimen-sionless groups. INTRODUCTION Several solutions to the various problems associated with the unsteady-state flow of gas through porous media have been recently presented in the literature.','" The cited publications have resented solutions for flow under ideal conditjons. The principal assumptions involved include: (a) the density of the gas obeys the perfect gas law; (b) the viscosity of the gas is constant; and (c) the gas permeability is constant. Few, if any, actual gases under reservoir conditions are believed to conform with the above, but the ideal solutions do provide the basis for making improved estimates on the performance of gas reservoirs. The purpose of this paper is to show the performance characteristics when assumption (c) is corrected for the slippage phenomenon or the Klinkenberg effect. This is believed to be a step nearer to reality. MATHEMATICAL DEVELOPMENT Case 1. Gas Flow — Ideal Conditions The equations describing the flow of gas under ideal conditions have been clearly presented in the cited literature; however, for completeness of this work they are repeated here. The basic differential equation describing the flow of gas is Equation (6). It may be derived as follows: The continuity equation, the perfect gas law and Darcy's law are combined to give: Manuscript received in the Petroleum Branch office Aug. 3, 1963 or If — is constant, Equation (5) is rewritten to form the basic Equation (6). or for the linear case A dimensionless equation is obtained by dividing through by (pl)z and making the substitutions shown below: The resulting equation is A similar procedure for the radial case leads to the following equations: where and Equations (11), (12), and (13) are those used by Bruce, et al., and Jenkins and Aronofsky for their computational work.

Jan 1, 1953

By D. B. RUSHNORE, K. A. Pauly

Bulletin. No. 41, May, 1910. ABBREVIATIONS. Al. Ind., Alliance Industrielle. am. Elec'n.. . American. Electrician. Bull. As. Ing. El Bulletin de la Association des Ingenieurs Elec- triciens Sortis de l'Institut Electrotecnique Montefiore, Liege. Bull. Soc. bilge d' Elec Bulletin de la Société belge d'Electriciens. Col. Guard . Colliery Guardian. D. R. P Deutsches Reich Patent. Dilly. Poly Dingler's Polytechniches Journal. E. & DI. Jour Engineering and Mining Journal. E. T. Zeit Electrotechnische Zeitschrift. Eclair. Elec. L'Eclairage Electrique. 1;1. Anzeig Elektrotechnischer Anzeiger

Sep 1, 1910

By Alvin F. Kroll

BUNKER Hill & Sullivan Mining & Concentrating Co. has three major sources of ore at present: high grade square-set ore, low grade caving ore, and low grade reclaimed washed jig tailing. These three ores constitute the feed to the 3000-tpd concentrator that produces lead-silver, zinc, and pyrite concentrates. Each ore has different characteristics of grindability, mineral particle size, composition, and content, but all are amenable to the same mill circuit and reagents. The gangue is primarily quartzite. The Bunker Hill concentrator is now using a coarse primary grind followed by a regrind of sand fractions of lead rougher tailing, lead middling, and lead cleaner tailing, and further regrind of sand fractions of zinc middling and zinc cleaner tailing. This is done in order to recover all valuable minerals at the largest size possible. The tendency to overgrind the ore particles, which are more easily ground than the gangue particles, is thereby reduced-lessening their loss in the flotation tailings. The coarse primary grind and regrind method has the advantages of: providing more selective grinding, minimizing sliming, giving a cleaner lead-zinc separation, and reducing mill requirements for reagents and water. Improved lead-zinc separation raises overall recovery and also increases lead and zinc recovery in the respective concentrates by keeping middling particles out of concentrate and tailing.

Jan 6, 1954

By F. Habashi

Siberia, a vast country rich in mineral resources and a large number of different ethnic groups. To the east of Lake Baikal is Buryatia with capital Ulan Ude. The Buryat are closely related to the Mongolians. Ulan Ude is connected to Ulaan Baatar (Ulan Bator) the capital of Mongolia by train – a 26 hours trip. Getting a visa to Russia is not a simple case. Visits to metallurgical research laboratories, Lake Baikal, and historical museums are enriching experience.

Jan 1, 2006

By James R. Hein

Methane and hydrogen sulfide vent from a cold seep above a shallowly buried methane hydrate in a mud volcano located 24 km offshore of Los Angeles, California in 800 m water. Bivalves, authigenic calcite, and methane hydrate were recovered in a 2.1 m piston core. Aragonite shells of two bivalve species are unusually depleted in 13C (to -19? d13C), the most 13C-depleted shells of marine macrofauna yet discovered. Carbon isotopes for both living and dead specimens indicate that they used in part carbon derived from anaerobically oxidized methane (AOM) to construct their shells. Although the?d13C values are highly variable among specimens, most fall within the range -12 to -19?. This variability may be diagnostic for identifying cold-seep/hydrate systems in the geologic record. Authigenic calcite is abundant in the cores down to about 1.5 m subbottom, the methane hydrate horizon. The calcite is strongly depleted in 13C d13C = -46 to -58?) indicating that AOM was the main carbon source. Three sources of methane are likely: a geologic hydrocarbon reservoir, and biogenic and thermogenic degradation of organic matter in basin sediments. Oxygen isotopes indicate that most calcite formed out of isotopic equilibrium with ambient bottom-water, under the influence of gas hydrate dissociation and strong methane flux. High concentrations of Ag, Hg, Cd, Tl, and other elements in mud volcano sediment reflect leaching of basement rocks by fluids circulating along an underlying fault. Fossil (geologic) methane was likely transported with these fluids.

Jan 1, 2005

By J. A. Finch

Samples of feed and product from a closed grinding circuit treating a heterogeneous lead-zinc ore were taken. The feed was subjected to laboratory batch grinding in a rod and ball mill with the objective of simulating the closed-circuit size distribution. It was concluded that the batch rod mill can closely simulate this product if only the over-all size is considered, but mineral-by-mineral large differences occur. If, as is suspected, the mineral sizes are the important factor in flotation, the differences could lead to problems in interpreting flotation results. An example of mineral recovery as a function of size is described to illustrate the potential problems.

Jan 1, 1979

By Irina A. Pulyaeva

Hydrogenetic Fe-Mn crusts play an important role in marine mineral-deposit research because of their widespread occurrence and high concentrations of valuable and rare metals. Most Fe-Mn crust deposits occur on the tens of thousands of seamounts found in the global ocean as well as on ridges and plateaus. Because of these circumstances, it is essential to clarify a number of outstanding issues with regard to Fe-Mn crust history and development, including controls on metal sources and concentrations. The first-order characteristics of Fe-Mn crusts as potential ore deposits include concentrations of metals (grade) and the thickness of crusts (tonnage), which vary depending on Fe-Mn crust structure and texture. Data on the structure, composition, age, and deposit characteristics will help define which factors are key for the creation of mineral accumulation and which combination of factors leads to the formation of potentially economic concentrations of metals. In this paper, we address the structure and characteristics of Fe-Mn crust stratigraphic sections collected from Central and Western Pacific seamounts. We describe the changes in mineralogical and chemical compositions of crust layers of different ages, the occurrence and regional distribution of these layers that correlate regionally, and reconstruct the paleoceanographic conditions that influenced crust growth.

Jan 1, 2010

By R. J. Reuss

Mina Maria is a high-grade, underground copper mine located in the Cananea district of Sonora, Mexico. The ore body is a massive sulfide breccia located in mountainous terrain. A major highway and an electric transmission line pass directly over the near-surface ore body. The mine is operated by Minera Maria SA de CV, a joint venture company that is 51 % owned by Empresas Frisco SA de CV and 49% by Cominco Resources International Ltd. Empresas Frisco is the operating partner. Production began in October 1990. The mining method used is undercut and fill. A continuous miner and a single-boom, hydraulic jumbo mine the ore. Backfill is a weakly cemented sand-gravel mixture that is pneumatically placed. The ore is treated by conventional crushing, milling and flotation. The Maria deposit is located about 40 km (25 miles) south of the Sonora-Arizona border and 11km (7 miles) northwest the city of Cananea and the Cananea Mine. The mine portal, at an elevation of 1780m (5840 ft), is on the east side of an important drainage divide. The mill site is situated about 800 m (2625 ft) northwest of the mine on the northwest side of the drainage divide where the drainage is more favorable. Its elevation is 1860 m (6100 ft) (Fig. 1).

Jan 1, 1992

By Blake M. Loring, Robert A. Colton

MELTING procedures for most metals and alloys usually include some provision for the control of oxygen, since this element frequently has some undesirable effect on the properties of the metal or alloy concerned. In the melting of the various bronzes, this is especially true, since oxygen can be introduced into the melt in a number of ways, most of which are difficult to control. In making bronzes from virgin materials, oxygen is usually present in the commercial grades of copper used; electrolytic he refined copper ingots usually contain from 0.02 to 0.05 per cent oxygen. When ingot metal or scrap bronze is used in the charge, oxides are almost always present to some degree. Under certain melting conditions and in certain types of melting equipment the atmosphere over the metal may be highly oxidizing. This, of course, may be desirable in the melting practice used, but is certain to introduce appreciable amounts of oxygen into the melt, and that may not be entirely desirable. From the foundry viewpoint oxygen may have several harmful effects on bronzes. The formation of excessive amounts of oxides may produce drossy metal, which, in turn, means dirty castings and a potentially high rejection rate. It is claimed, too, that oxides in the metal may combine with hydrogen to form steam and thereby produce porosity in certain of the bronzes. The presence of certain refractory oxides, such as SnO2, may be undesirable from the viewpoint of making machining difficult, or as possible stress-raisers in the metal matrix. It is often said that excessive oxide present in the liquid metal makes the metal run sluggishly. Since it appears impractical to try to control the amount of oxygen introduced into the metal beyond taking the economical limit of precaution about charging dirty scrap, it would seem that control of the oxygen content of the liquid metal offers the most promising approach to this problem. This might be done by using slags, or covers, or by the use of some element or compound added to the melt to remove oxygen preferentially. Most aspects of this problem have been considered and considerable work has been done along these lines. A reconsideration of the problem is indicated, however, by the controversial nature of the evidence at hand, especially on the possibility of using a chemical deoxidizer to control the oxygen content of bronzes. CHOICE OF DEOXIDIZER The choice of the chemical agent selected as a deoxidizer would naturally depend first on the alloy in which it is to be used; in this particular case the alloy is Navy gun metal. In Table I are listed a group of elements that might be considered as

Jan 1, 1946

By Jerry M. Eyster

The Bush Administration is committed to reducing emissions from existing power plants Candidate George W. Bush said: The key to reducing emissions from older power plants on the federal level is to cap emissions on a level that makes sense?. And harness the power of the market place and provide economic incentives to produce better environmental results. I would want to make sure that any program we pursue does not result in excessive and unnecessary increases in electric bills.

Jan 1, 2002

An Integrated Study of Bubble-Particle Attachment Mechanisms

Sep 13, 2010

By J. N. Hobstetter, J. J. Becker

Slip lines in deformed copper single crystals exhibit very pronounced cross-slip and clustering if the stress axes are not too far from <100>. This orientation dependence seems to persist whether or not attempts are made to reduce the bending constraints of ordinary mechanical tests. THE purpose of this paper is to report some microscopic features of the plastic deformation of copper single crystals. The material used was OFHC copper obtained from the American Brass Co. Single crystals about 3 in. long and 5/16 in. in diameter were made by lowering graphite crucibles containing this copper out of the hot zone of a vertical tubular furnace at a rate of 1 1/4 in. per hr. The furnace atmosphere was nitrogen. The orientations of the crystals were determined by the back-reflection Laue technique.&apos; The X-ray spots usually indicated a slight lineage structure of not more than a degree or two. The crystallography of slip is discussed in Schmid and Boas.&apos; The terms classical slip, cross-slip, and conjugate slip are used here with the same meanings as in ref. 3. Compression Specimen 17 (Fig. 1) was selected because the resolved shearing stresses on eight slip systems dif- fered at most by a factor of 1.2. It was hoped that in this situation such effects as cross-slip might be made more prominent. Two intersecting planes parallel to the stress axis were ground on the crystal, using optical abrasive on a lead lap. The large plane was approximately perpendicular to the plane of the axis and the primary slip direction. Its exact orientation was determined by X-ray. The smaller made an angle of 49" with the larger, measured by reflecting a small light source. The specimen was etched with nitric acid until its diameter had been reduced 0.010 in., and then was given a metallographic polish and very

Jan 1, 1954

By Christopher Mark

Despite more than half a century of experience with roof bolting, no design method has received wide acceptance. To begin to improve this situation, National Institute for Occupational Safety and Health (NIOSH) conducted a statistical study of roof bolt performance at a number of mines throughout the U.S. Case histories were collected from 37 mines with a variety of roof bolt types and patterns in a wide range of geologic environments. Performance was measured in terms of the number of roof falls that occurred per 10,000 ft of drivage. The study found that roof falls are rare when the roof is strong and the stress is low, even with light roof bolting patterns. The focus of this paper is on the more difficult conditions, where the roof is weaker and/or the stress is higher. Analysis of the results led to guidelines that can be used to make preliminary estimates of the required bolt length, capacity, and pattern. The guidelines are based on the depth of cover (which correlates with stress) and the roof quality (measured by the Coal Mine Roof Rating (CMRR), and the intersection span. Another contribution is a formula for estimating the horizontal stress level in the eastern U.S. coalfields as a function of the depth of cover. The design guidelines are currently being implemented into a computer program called Analysis of Roof Bolt Systems (ARBS).

Jan 1, 2001

By D. C. Rance

"The Quintette Coal Limited property is located in the northeast coal area of British Columbia.A basic agreement with the Japanese steel industry was executed on January 27, 1981 for the sale of 69.5 million tonnes of Quintette metallurgical coal over a 14.5-year period. This contract period can be extended by five years by mutual agreement. Sale agreements have also been signed for the sale of 19.4 million tonnes of oxidized coal over a 15-year period.Work started on site development in the late summer of 1981, and at present, two of the four eventual pits-the McConkey and Frame-are under development.The pits are currently in a prestripping phase. These pits are notable for the stripping volumes that have to be removed from relatively small pit areas. In order to provide for the required detailed rapid short-range planning of these pits, engineering will be computerized, as will the truck dispatch system.The mining area lies 21.1 km from the plant site by road and the transport of raw coal to the plant is by means of a high-speed conveyor system which has a total length of 13.4 km with a vertical drop of 740 m.The surface plant facility was designed on a modularized basis to facilitate maintenance, and is designed to enable the use of gravity f low of raw coal and heavy media in the plant to minimize the use of pumps.The construction of the plant and mine site facilities is ongoing, and the first coal production is scheduled for early December 1983.IntroductionQuintett e Coal Limited is a Canadian company incorporated in the province of British Columbia in 1971. Denison Mine s Limited is the manager of Quintette&apos;s activities. Equity in Quintette Coal Limited is held by several shareholders, with interests as follows: Denison Mines Limited, 50%; Charbonnages de France International S.A., 12%; and Japanese interest, 38%."

Jan 1, 1983

By F. G. ROCKWELL

ALTHOUGH the diamond as a gem stone dates back many hundreds of years its use industrially, at least to any extend is recent. The old adage: "Use a diamond to cut a diamond" indicates that some industrial use was made of this material in cutting and polishing many years ago. It also put to various other industrial by the Romans. General industrial use however was never developed to any considerable extent until about the time of the first World War. It is definiely known however, that a Swiss watchmaker, M. Leschot by name, invented a diamond drill in or about the year 1862, Today, some 75 or 80 per cent of the total didamods produced are used in industry. There are two main classifications of diamonds : (1) carbonados or "black diamonmds," and (2) diamonds proper.

Jan 1, 1944

By Blake M. Loring, Robert A. Colton

MeltiXg procedures for most metals and alloys usually include some provision for the control of oxygen, since this element frequently has some undesirable effect on the properties of the metal or alloy concerned. In the melting of the various bronzes, this is especially true, since oxygen can be introduced into the melt in a number of ways, most of which are difficult to control. In making bronzes from virgin materials, oxygen is usually present in the commercial grades of copper used; electrolytic fire-refined copper ingots usually contain from 0.02 to 0.05 per cent oxygen. When ingot metal or scrap bronze is used in the charge, oxides are almost always present to some degree. Under certain melting conditions and in certain types of melting equipment the atmosphere over the metal may be highly oxidizing. This, of course, may be desirable in the melting practice used, but is certain to introduce appreciable amounts of oxygen into the melt, and that may not be entirely desirable. From the foundry viewpoint oxygen may have several harmful effects on bronzes. The formation of excessive amounts of oxides may produce drossy metal, which, in turn, means dirty castings and a potentially high rejection rate. It is claimed, too, that oxides in the metal may combine with hydrogen to form steam and thereby produce porosity in certain of the bronzes. The presence of certain refractory oxides, such as SnOz, may be undesirable from the viewpoint of making machining difficult, or as possible stress-raisers in the metal matrix. It is often said that excessive oxide present in the liquid metal makes the metal run sluggishly. Since it appears impractical to try to control the amount of oxygen introduced into the metal beyond taking the economical limit of precaution about charging dirty scrap, it would seem&apos; that control of the oxygen content of the liquid metal offers the most promising approach to this problem. This might be done by using slags, or covers, or by the use of some element or compound added to the melt to remove oxygen preferentially. Most aspects of this problem have been considered and considerable work has been done along these lines. A reconsideration of the problem is indicated, however, by the controversial nature of the evidence at hand, especially on the possibility of using a chemical deoxidizer to control the oxygen content of bronzes. Choice of Deoxidizer The choice of the chemical agent selected as a deoxidizer would naturally depend first on the alloy in which it is to ~he used: in this particular case the alloy is Navy gun metal. In Table. I are listed a group of elements that might be considered as deoxidizers for bronze, with some of their properties that should be considered in

Jan 1, 1946

By Blake M. Loring, Robert A. Colton

MeltiXg procedures for most metals and alloys usually include some provision for the control of oxygen, since this element frequently has some undesirable effect on the properties of the metal or alloy concerned. In the melting of the various bronzes, this is especially true, since oxygen can be introduced into the melt in a number of ways, most of which are difficult to control. In making bronzes from virgin materials, oxygen is usually present in the commercial grades of copper used; electrolytic fire-refined copper ingots usually contain from 0.02 to 0.05 per cent oxygen. When ingot metal or scrap bronze is used in the charge, oxides are almost always present to some degree. Under certain melting conditions and in certain types of melting equipment the atmosphere over the metal may be highly oxidizing. This, of course, may be desirable in the melting practice used, but is certain to introduce appreciable amounts of oxygen into the melt, and that may not be entirely desirable. From the foundry viewpoint oxygen may have several harmful effects on bronzes. The formation of excessive amounts of oxides may produce drossy metal, which, in turn, means dirty castings and a potentially high rejection rate. It is claimed, too, that oxides in the metal may combine with hydrogen to form steam and thereby produce porosity in certain of the bronzes. The presence of certain refractory oxides, such as SnOz, may be undesirable from the viewpoint of making machining difficult, or as possible stress-raisers in the metal matrix. It is often said that excessive oxide present in the liquid metal makes the metal run sluggishly. Since it appears impractical to try to control the amount of oxygen introduced into the metal beyond taking the economical limit of precaution about charging dirty scrap, it would seem&apos; that control of the oxygen content of the liquid metal offers the most promising approach to this problem. This might be done by using slags, or covers, or by the use of some element or compound added to the melt to remove oxygen preferentially. Most aspects of this problem have been considered and considerable work has been done along these lines. A reconsideration of the problem is indicated, however, by the controversial nature of the evidence at hand, especially on the possibility of using a chemical deoxidizer to control the oxygen content of bronzes. Choice of Deoxidizer The choice of the chemical agent selected as a deoxidizer would naturally depend first on the alloy in which it is to ~he used: in this particular case the alloy is Navy gun metal. In Table. I are listed a group of elements that might be considered as deoxidizers for bronze, with some of their properties that should be considered in

Jan 1, 1946

Comparison of the Zadra, Anglo-American and organic solvent procedures for desorption of gold from activated carbon loaded in carbon-in-pulp gold circuits indicates that the Anglo American and the organic solvent procedures are considerably more effective than the commonly used Zadra procedure. Organic solvent elution procedures, particularly those using acetonitrile and acetone, can provide effective gold elution and very high concentrations of gold in eluate solutions. The operational simplicity and effectiveness of the Anglo American procedure would appear to make it the most satisfactory procedure available at the present time but this may change as the solvent elution procedures become better developed. INTRODUCTION The carbon-in-pulp technique has been introduced into the gold processing industry to by-pass the often lengthy CCD and filtration steps required in the conventional Merrill Crowe cyanidation procedure for gold recovery. Adsorption of gold on to carbon is also a valuable technique for recovering trace amounts of gold from low level waste streams from conventional processing procedures.

Jan 1, 1982

A. L. FIELD, Cleveland, Ohio (written discussion*.-)In equation 2, B is used to denote the ratio of bases (lime plus magnesia ) to acids (alumina plus silica) it being stated that this ratio gives more concordant results than the ratio either of bases to silica, or of lime to silica. I find, however, that, by making use of the ratio between true CaO (CaO by analysis minus sulfur calculated to CaS) to acids, equation 2 may he modified to agree with the observed facts within an average error of 0.0041 per cent. sulfur instead of 0.0045 per cent. The revised equation is s = 0.072 + 0.01835 - 0.00061 (t - 1400) - 0.0403B where B is the ratio of true CaO to Al2O3 Plus Si02, and the other symbols have the same significance as before. I would not appear to stress too much this slightly better agreement of the revised equation with the observed sulfur. Yet I believe that the use of this ratio of true CaO to acids is to be preferred, if for no other reason than the fact that it is more in harmony with the previous findings of the Bureau of Mines with regard to the effect of magnesia and other impurities on slag viscosity.1

Jan 12, 1919