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By H. W. Norman

DURING the first few years of the new atomic age the Colorado Plateau was the focal point of uranium exploration. There was little incentive to expend time and effort in an area so far removed from the known deposits as the Pacific Northwest, and there were too few local prospectors to cover the vast territory involved. In 1949 the AEC established an exploration office in Spokane to evaluate the uranium potential of the northwestern states. Interesting occurrences were found in the Coeur d'Alene district in Idaho and in the Boulder Batholith of central Montana, but the AEC discontinued the Spokane office in 1952, and for the next two years prospecting in the area was negligible. In April 1954 John and James LeBret, prospecting on the Spokane Indian Reservation with an ultra violet lamp, located an occurrence of the fluorescent uranium mineral autunite. This discovery was not announced until the following September, after a lease had been granted by the Spokane tribe. Exploratory drilling carried on by the AEC throughout the winter verified the existence of a commercial orebody. This property, the Midnite mine, has since developed the largest known ore reserve in the district.

Jan 6, 1957

By Theodore Simons

The rapid and comparatively recent development of flotation has opened so fascinating a field for study and research that the older processes of gravity concentration no longer receive the attention they deserve. The early work of Munroe1 and Richards,2 and the more recent contributions by Clevenger and Coe,3 Laist and Wiggin,4 Ammon,5 Bardwell,6 Crowfoot,7 and Hayden8 to mention only some which have appeared in our own Transactions-and by Schulz,9 have furnished so much data that to offer something new seems a difficult task. It is still possible, however, to present known facts from a different point of view, and, with this in mind, the writer has undertaken to express basic principles of gravity concentration in terms of simple mathematics and mechanics; the conclusions thus reached will be found to correspond, in general, with those obtained by experimental methods. Rittinger, in his classic Aufbereitungskunde (1867), reached analogous conclusions by way of intricate higher mathematics, for which reason his interesting investigations have remained a sealed book to most of us. The writer hopes that a more elementary treatment of the subject, based in part on Rittinger's methods, may, arouse new interest in the study of basic principles.

Jan 7, 1922

By F. R. Ingalsbe

THE proposed revision of the mining law as set forth in the Arentz Bill, now before Congress, is centered about the pretty commonly acknowledged f act that the present law is outlawed both by the large mining companies and the United States Land Office. By common agreement, the law of the apex is non-opera¬tive as between adjacent properties in many instances, and this practice is becoming more common. - If this is a fact, there is no escape from the conclusion that the law is antiquated and should be revised to meet modern conditions more equitable. The thing to be considered seriously is in what direction and to what extent the laws should be changed. Before deciding this, it is logical to inquire in what particulars the present law is troublesome or useless. This was all threshed out by the committee of the Bureau of Mines that worked out the proposed bill, but their testimony was not placed before the public, so far as 1 am aware. Most mine managers and engineers connected with producing properties are a unit in agreeing that the law as applied to the underground extension of orebodies, that is, the "law of the apex," as it is called, is the source of more litigation and expense than any other phase of the law, or perhaps than all other phases combined. This being true, it seems that this part of the law should be changed. Another phase which is troublesome and will continue to be so long as there is unpatented mineral land on the Public Domain, is the discovery requirement. The present law requires that a dis¬covery be made before a claim is staked and the courts certainly agree that such must be the case before patent issues.

Jan 7, 1922

By W. J. Keep

We have found that our graphic representations were, in some cases, not perfectly understood. In the tables by which we illustrate all our tests, the records appearing in the vertical columns between the rulings are the results of the tests of iron having the percentages and characteristics noted at the top of the column. The record is made by a short horizontal line in such vertical columns. It is located in horizontal spaces, which divide the table into units of measure, to indicate the value of the record. For example, in the upper part of Table VII. is recorded the transverse strength of the series of tests with white iron and aluminum, which were reported in our former paper. The numbers at the extreme top are the test-numbers. The fractional numbers below are the percentages

Jan 1, 1890

By Dale S. Preece

INTRODUCTION In 1975 Congress passed the Energy Conservation Act to establish a U. S. Strategic Petroleum Reserve (SPR) with a capacity of 750 million barrels of crude oil. The most economic storage medium was determined to be salt caverns leached in salt domes in Louisiana and Texas. Salt caverns existed at several sites when the reserve was created. These were obtained by the U. S. Department of Energy (DOE) and used to initiate SPR oil storage. In order to meet the storage capacity approved by Congress, new caverns also had to be leached. To support the resulting design effort, finite element computer programs have been used to determine the creep closure and structural stability of salt caverns Using site specific material properties including creep models, elastic moduli and fracture data, the finite element analyses have replaced earlier empirical approaches to cavern design. This report presents results of such finite element analyses to determine the best cavern roof shape and the minimum pillar to diameter ratio, P/D. These numerical predictions indicate that the current cavern design is safe. FINITE ELEMENT AND MATERIAL MODELING The finite element program used in this study has existed for approximately four years. Its theoritical basis (Key, et al, 1980) and application are well documented It was originally developed to predict the creep around mined openings In bedded rock salt for the Waste Isolation Pilot Plant (WIPP) The program was tested by modeling the creep of salt around a drift and by comparing the results with the predictions of eight other structural computer codes (Morgan, et al, 1981) Since then the program has had continual use for calculations to support the WIPP (Miller, et al, 1982) For about two years the

Jan 1, 1984

By A. Tobey Yu

Despite its inherent low Btu content, western coal's low sulfur content may provide a near-ideal answer to satisfy US goals for clean air and energy self-sufficiency. Vast reserves, amenable to low-cost strip mining, serve as a powerful economic basis for its viability as a primary and dependable source of energy for the coming decades. A major consideration, the solution of which may not be obvious, is the transportation cost. These deposits are remote from the utilities of the heavily populated eastern regions of the US (Fig. 1). A coal mine in Montana is likely to be more than 1500 miles from its utility market, while an eastern coal mine may be situated only 200 miles away. Thus, the question raised is: how can the haulage cost of western coal be substantially reduced to an acceptable level?

Jan 7, 1975

By Charles J. Deegan

The purpose of this paper is to point out some features of the position of fuel oil and it's relationship to the economic balance and price structure of the petroleum industry. The term "fuel oil" as used in this paper includes crude used as fuel as well as refined gas oil and fuel oil. The period covered, from 1922 to date, may be characterized as the new normal era after the post-war inflation and deflation. In order to establish a proper perspective, the figures on consumption of the principal products of petroleum are shown in Table 1. This table shows that fuel oil and gasoline made up the bulk of the total demand in 1928 just as they did in 1922. There has been so much comment about the enormous increase in gasoline consumption that it may come as a surprise to some people to find that fuel oil is still at the head of the consumption list, in point of volume at least, and seems likely to hold that place for at least another year. Having established the fact that gasoline and fuel oil are by far the most important products, the remainder of this paper will deal almost entirely with these two items.

Jan 1, 1929

The Library of the above-named Societies is open from 9 A.M. to 10 P.M. on all week-days, except holidays, from September 1 to June 30, and from 9 A.M. to 6 P.M. during July and August. The Library contains about 55,000 volumes, including sets of technical periodicals and the publications of scientific and technical societies. Members of the Institute, with few exceptions, are forced to spend a portion of their time in localities isolated from sources of information. To these the Library can render valuable service through correspondence; letters requesting information will receive special attention. The Library is prepared to furnish references and copies of articles mining and metallurgical subjects; to determine the existence of mining maps, and to furnish general information as to the geology and mineral resources of all countries. All communications should be made as definite as possible so that the information received may be what is desired and not include collateral matter which may not be of interest. The time spent in searching for such collateral matter will be saved, and the information will be sent more promptly and in more usable shape. The members of the Institute can be of service to the Library by forwarding copies of mining reports, maps privately issued, and similar material, which will be classified, indexed, and made available to other members. Suggestions for additions to the Library, either by purchase or personal solicitation as gifts, will be welcomed. It is hoped that members while in the city will use the Library freely, and assurance is given that most careful service will be rendered to them.

Jan 4, 1915

By B. H. Sage, W. N. Lacey, W. M. Morris

The volumetric behavior of isobutane at temperatures below its critical temperature has been studied by several investigators. Seibert and Burrelll measured the vapor pressure of isobutane from the ice point to the critical temperature. Dana and co-workers2 determined among other thermodynamic quantities the density of the saturated liquid and the saturated gas and the vapor pressure from approximately 0 to 130 F. Sage and Lacey3 studied a number of the thermodynamic properties of this hydrocarbon from 70" to 250" F. The specific volume in the gas and liquid region was determined at pressures up to 3000 Ib. per sq. in.? throughout this temperature interval. In addition, the vapor pressures were measured at 30" intervals. These data taken together serve to establish the thermodynamic behavior of isobutane at temperatures between 0" and 250" F. with reasonable accuracy. However, apparently there are no data available at the higher temperatures. For this reason an investigation of the volumetric behavior of isobutane at temperatures between 100" and 460" F. was carried out with apparatus that has been described in another paper (p. 136, this volume). Materials The isobutane used in this investigation was obtained from the Philgas Division of the Phillips Petroleum Co. That company's special analysis upon this sample indicated it to contain less than 0.03 mol per cent of impurities. In order to avoid traces of noncondensable gases, this hydrocarbon material was subjected to two successive fractionations at a high reflux ratio in a column approximately 4 ft. long and % in. in diameter, which was packed with small glass rings. The middle portion of distillate from the first fractionation was used in the second fraction-ation and a portion of the overhead from this second distillation process was repeatedly condensed at liquid-air temperatures at a pressure only slightly above the sublimation pressure of isobutane at this temperature.

Jan 1, 1940

By Malcolm J. McPherson

INTRODUCTION The use of computers to assist the mine ventilation engineer began to grow in the early 1950s when electrical analogue devices were developed for the analysis of mine airflow systems in Europe and the United States (l,2,3). The need for quantitative planning of airflows in mines had become pressing and analogue computers fulfilled a useful purpose for over a decade. From about 1964 onwards, digital computer programs for mine ventilation network analysis became available (4,5) and, superseding the analogues, spread rapidly throughout the major mining countries. The successful implementations of such programs resulted in further research being directed towards the development of simulation programs to model the quality as well as the quantity of air flowing through underground workings. It is no understatement that digital computers have revolutionised environmental planning techniques in modern mining industries. This paper discusses the complex interaction of natural and mining factors which governs environmental hazards in underground mines and further indicates some of the simulation techniques which have entered practical usage or are at an advanced stage of development. THE PROBLEM OF ANALYSING THE MINE ENVIRONMENT The traditional methods of approaching environmental problems underground were based largely on empirical or intuitive techniques. The reason for this lay in the intricate relationships which exist between the many variables that influence the mine environment - and which limit the use of purely analytical methods to the simplest of cases. In order to illustrate the need for simulation techniques, Table 1 shows the three most widespread mine environmental hazards

Jan 1, 1977

By R. W. Raymond

PROFESSOR W. P. BLAKE, in a note to his Catalogue of California Minerals, pointed out that the milling districts of the Pacific slope are arranged in parallel zones, following the prevailing direction of the mountain ranges. This interesting generalization has been more frilly illustrated and connected with the geological history of the country by Mr. Clarence King, who sums up the observed phenomena as follows : " The Pacific coast ranges upon the west carry quicksilver, tin, and chromic iron. The next belt is that of the Sierra Nevada and Oregon Cascades, which, upon their west slope, bear two zones, a foot-hill chain of copper mines, and a middle line of gold deposits. These gold veins and the resultant placer mines extend far into Alaska, characterized by the occurrence of gold in quartz, by a small amount of that metal which is entangled in iron sulphurets, and by occupying splits in the upturned metamorphic strata of the Jurassic age. Lying to the east of this zone, along the east base of the Sierras, and stretching southward into Mexico, is a chain of silver mines, containing comparatively little base metal, and frequently included in volcanic rocks. Through Middle Mexico, Arizona, Middle Nevada, and Central Idaho is another line of silver mines, mineralized with complicated association of tli6 base metals, and more often occurring in older rocks. Through New Mexico, Utah, and Western Montana lies another zone of argentiferous galena lodes. To the east, again, the New Mexico, Colorado, Wyoming, and Montana gold belt is an extremely well-defined and continuous chain of deposits." These seven longitudinal zones or chains of mineral deposits must

By Reino Kurppa

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

Jan 1, 1969

By O. U. Bradley

THE methods of handling the oil output of the mid-continent fields are not unlike those practised in other oil fields of the United States, and it is not expected that this paper will present any entirely novel ideas. Some features of the practice of handling this oil may be of interest, however. WOODEN CAGING TANKS Practically all of the oil sold to pipe lines and other purchasing agencies throughout the Mid-continent field is gaged from wooden tanks. Steel gaging tanks are slowly coming into use, and are preferable in many ways-leakage and evaporation are reduced, and the strapping and recalculation of capacities are unnecessary. The wooden tanks are slightly coned to facilitate tightening the hoops. The-sizes in, common use are 250, 500, 800 and 1600 bbl. The number and the capacity of the gaging tanks upon any producing oil property depend upon its production, and the facilities for disposing of the output. The 1600-bbl. size was the most common in the Cushing field, particularly during the period of flush production. The tanks are distributed over the leased premises in groups of two, three, and four tanks each, and these are filled from flow tanks, or through direct pipe connections with the heads of the wells. Flow tanks are merely temporary reservoirs to facilitate the transfer of oil from the wells to the gaging tanks. They diminish fire risk,, and are considered indispensable on small producing properties where .water is pumped with the oil, as they permit the refuse and water to settle out before the production is run to the gaging tanks.

Jan 3, 1918

By P. Somasundaran

INTRODUCTION Large amounts of mineral values are discarded today as fines and ultrafines, because of inadequate technology to process them economically. Most conventional mineral processing techniques fail in the sub-sieve range. Fines respond poorly to processes such as flotation either due to change in mineralogy and surface composition or even simply due to the direct effect of their smallness in size on collision and adhesion rates between them and air bubbles. Indeed if the poor flotation is due to the smallness in size, a solution must rest in aggregating the fines. Inorganic electrolytes as well as polymers have been successfully used as flocculants in the past for obtaining increased flotation of colloidal material from waste water effluents. In mineral beneficiation, this technique can be profitably used if the process of flocculation can be made to take place selectively. The power of the selective flocculation technique has already been proven, with the successful application of it in the case of beneficiation of low grade iron ore by the Cleveland-Cliffs Iron Ore Company and potash ore by Cominco. The process holds tremendous potential when it is followed by flotation, elutriation, etc. Today its application is, however, limited to the above two cases and it has become clear that a full understanding of the process will prove helpful for developing solutions to various problems that exist both at the basic and applied levels. In this paper, principles that are known to govern selective aggregation processes such as selective flocculation, carrier flotation and spherical agglomeration will be examined and areas of uncertainties will be identified.

Jan 1, 1979

By T. J. Whalen and Michael

The grain shape of the carbide in nickel-bowled ad cobalt-bonded titanium carbides was studied by microgiaphic examination, and the influcence of sintering atmosphere, sintering substl-after, ami the amount of metal binder on the grain shape was determined. If was found that the Carbide grain cross sections in the nickel and cobalt cermets ranged from round to angular, depending on the sintering conditions. The spheroidization of the carbides in both cobalt-bonded and nickel-bonded titanium carbides may be attribicted to oxygen. In the course of studies on titanium-carbide base cermets, various investigators have reported on the shape of the carbide grains, and it was noticed that grain shapes were obtained which were either spheroids, or polygons with rounded or square edges. It was also noted that the shapes of the carbide grains changed with time or composition. skolnickl showed that the titanium-carbide grains. after infiltration in vacuum with nickel tended to spheroi- dize with time. The titanium-carbide skeleton was located on a beryllia plate during infiltration. Gur-land,' who studied the microstructure of titanium carbide-cobalt compacts, showed that the carbide grains are round after 1 hr at 1450oC in a hydrogen atmosphere and angular after 7 hr at the same temperature. Goetzel3 has found that the carbide grains in compacts with a high binder content. 40 to 60 pet. tend to be spheroidized. whereas Blumenthal and silverman4 pointed out that the higher binder contents could yield either round or rectangular grains with rounded edges. depending on the nature of the binder. It is the purpose of this paper to present experi-

Jan 1, 1961

By Harrison R. Cooper

Computer process analysis and control techniques are overcoming major hurdles to acceptance in the mineral industry. With the growing list of new advances characteristic of a rapidly maturing discipline, management of the companies on the leading edge are keenly aware of the advantages of using computer methods in process applications. Significant advancement is already evident in such technical areas as operations research, mathematical modeling, statistical methods, and computer-based procedural techniques. The early advances during the past decade are already documented in prior symposium proceedings of this series. Thus, the currently active areas of the advancing technology are emphasized here. This section deals with applications in pyrometallurgical and kiln processes. The two sections which follow deal with concentrating operations from two points of view: 1) mathematical modeling, and 2) on-line control. In the metallurgical field, emphasis on developing effective process computer applications for the steel industry began in the late 1950's. Simulation techniques also received substantial attention. The steel industry was soon joined by the cement industry in the development of computer methods for process applications. Computers were in use for feed-material blending and kiln control in the early 1960's. Computer development in other pyro processes, such as aluminum reduction and glass-making, also marked significant advances by the mid 1960's. Aluminum smelter potline control is a nearly universal application at this point, and the development of glass furnace computer process control represented a recent important technical advance in digital control techniques. Steel Hot strip rolling was the earliest significant process computer application in the metallurgical industry. Computer control of rolling mill operations is now a steel mill standard component, particularly in plants newly placed into production. 1, 2 Initial computer installations principally carried out procedural routines in setting mill clearances for production lot control. Recent developments are leading toward feedback control based on mathematical model techniques. 3

Jan 1, 1969

[ ] Granville S. Borden (Mining Taxation, P. 1049) has written two other published articles on the subject, Taxation and Mineral Resources, and An Income Tax Program for Mineral Producers. Both articles appeared in Mining Engineering. He is presently employed by Standard Oil Co. of California as a special tax counsel. He holds an LL. B and an LL. M from George Washington University and a Bachelor of Science in Mining from the University of California. He has been chairman of the Taxation Committee of the Minerals Economics div. of the AIME. Borden fishes, plays golf, prospects, and performs mineral analysis as hobbies. [ ] Charles C. Towle (co-author, Uranium Deposits of the Grants District, New Mexico, P. 1037) graduated from the Colorado School of Mines with a degree in Geological Engineering. He was a member of Sigma Nu; Theta Tau, an honorary professional society; Blue Key, honorary social society; the glee club and quartet, and a member of the student council. He has been a mucker, driller, flotation operator and mill shift boss for the Clear Creek-Gilpin Co., Idaho Springs, Colo.; Geologist, chief engineer, and chief geologist for Patino Mines & Enterprises Consolidated, Inc., Bolivia; appraisal engineer and part-time geology student, Denver; office geologist for Geology Dept., special Engineering div., Sea Level Canal Studies, Panama Canal; and geologist, div. of Raw Materials, USAEC, Grand Junction, Colo. He is currently chief of the Denver Exploration Branch, div. of Raw Materials, USAEC, Denver. Towle was at one time a tournament golfer, playing three and four times a week. While working in South America he played in numerous tournaments. Today, although playing only occa sionally, he shoots in the low eighties.

Jan 1, 1952

By A. J. Weinig

The method described is a modification of Schutzenberger's whereby the solution in titrations and the standards are protected from the atmosphere by a layer of kerosene. Indigo-disulfonate is the indicator and sodium hydrosulfite the standard. The method is rapid and delicate. It has been tried on a variety of mill solutions and mill men have found the method of value. THE important part that dissolved oxygen plays in the cyanide treat-ment of gold and silver ores is commonly recognized by most metallurgists and mill men.. But heretofore there has been no simple method on which the mill man could rely for determining the amount of oxygen in the various mill solutions. A few methods are adaptable to the, laboratory, such as the gasometric1 determination by actually measuring the oxygen. Winkler's2 iodometric method, and Schutzenberger's3 method, which depends on the reducing action of sodium hyposulfite on a blue solution of indigo carmine; but these are not readily adaptable to the needs of the mill man and cannot be applied to cyanide solutions without modification. The gasometric method is the most accurate but it takes too long to complete a determination. White's' method (a colorimetric method that depends on the degree of coloration imparted to a solution of pyrogallic acid in the presence of caustic soda) although much more rapid than any of the methods named, often gives misleading results on account of grading of colors of different solutions, which nearly always contain various kinds of salts. The method herein described was devised for the use of the mill man, the aim being to develop a simple, practical, accurate method. It is a modification of the Schutzenberger method and depends on the reducing

Jan 8, 1924

By A. Kenneth Schellinger

DURING the comminution of a brittle material in the presence of dry air, no known phase change or chemical reaction takes place. The energy changes associated with the comminution are those of the transformation of kinetic energy into heat energy and the energy absorption represented by the actual rupture of molecular and/or ionic bonds. The random nature of the actual grinding process in a tumbling-mill often precludes the effective application of a rupture force on each individual particle of brittle mineral present. The result must be a great deal of useless vibration on an atomic scale in both the brittle mineral and the grinding medium below the elastic limit, which vibration is eventually manifested as heat energy in the mill. The actual rupture of molecular, or ionic, bonds creates new surface on the brittle minerals; each square centimeter of this new surface then must possess a number of potential bonds, each of which could reform theoretically with the release of energy. The sum total of this potential energy of bonding per unit of new surface, minus bond satiation effects of the enclosing gas or liquid, must be the surface energy of the mineral. If the comminution of the brittle mineral were carried out within the chamber of a calorimeter, the energy released as heat could be determined rather accurately. Moreover, the total kinetic energy input to the comminuting mass (mineral and medium) conceivably could be derived by a suitable torquemeter and revolution counter if the whole calorimeter were revolved. The difference between these two energy figures should then represent the net energy (gross energy input-heat energy output) used in creating

Jan 6, 1951

By Galen Clevenger

TELLURIUM has had the rare and unpleasant distinction of having fewer uses than any of the other common elements; indeed, it has had no regular or important uses. It is not only a useless and disagreeable element, but to the metallurgist it has been a nightmare. The interference of tellurium with the recovery of gold and silver from certain ores, as well as the difficulties it occasions in the electrolytic refining of copper, lead, and silver, are too well known to require enumeration here. In fact, the potential producers of the element have been quite willing to throw the crude products from which it might be recovered into the sewer. First isolated from a gold ore in 1782, although remaining a practically unknown element to the general public, it has long been a guiding star to the Western prospector in his quest for the "golden fleece." On the burning sands of the desert, in the frigid North, and in the mountain fastnesses of the more temperate regions of this and other continents, he has endured all manner of hardships in his search for tellurides; for where he found indications of tellurium, there he expected also to find rich deposits of gold and silver. This peculiar superstition, that tellurium, associates itself in nature with the precious metals, is not with-out reason, for witness the fabulously rich gold tellu-ride deposits of Cripple Creek and Western Australia. Selenium, the sister element of tellurium, which it resembles in many of its properties, was first isolated in 1817. It is found in small amounts in certain native sulfur deposits, and in many copper and silver ores from all parts of the world. Until a few years ago, selenium, like tellurium, was practically useless. The, unusual property of having its electrical conductivity influenced by light has long been known. Selenium cells, which for many years have been a scientific curios-ity, in the future may come to be of more commercial importance, but this use could scarcely absorb any large amount of the element.

Jan 1, 1923