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By Joel N. Van Sant

THIS REPORT describes the occurrence, mining, and use of refractory clay in Colorado within Region III of the Federal Bureau of Mines, which includes the States of North arid South Dakota, Nebraska, Wyoming, Colorado, Utah, New Mexico, and Arizona. Field work by the Bureau of Mines, United States Department of the Interior, included examination of active and abandoned refractory-clay mines as well as a reconnaissance survey and sampling of numerous clay-bearing formations exposed in Colorado. Information from the survey and the sampling will help guide private industry in its search for virgin sources of refractory clay. Library research of published and unpublished reports from various Federal, State, and private sources was conducted during the early phase of the investigation. Most of the refractory clay mined in the Denver-Golden district of Colorado is not used for refractory purposes but is blended with other clays in the manufacture of structural clay products. The predominantly flint-clay de-posits in the Pueblo and Fremont County districts are mined and utilized chiefly in fabricating refractory products.

Jan 1, 1959

By John H. Soule

"Although known since 1902, the Capitan iron deposits have not been mined, mainly because of the low grade of the ore. Only a small amount of exploratory work has been done since the discovery. C. H. Johnson, district engineer of the Bureau of Mines in New Mexico in 1942-45, visited the property; as a result, preliminary sampling of the property was done in 1943.3/ Owing to the results of this preliminary work, an extensive development program by wagon drilling was planned and executed early in 1944.4/ Equipment available at that time was limited in the depths that could be reached; and, as geologic studies indicated the possibility that other limestone beds below the surface might have been replaced by iron minerals, a supplementary development program by churn drilling to reach greater depths was prosecuted in late 1947 and early 1948, with the author as project engineer.The following sections note the location and accessibility of the deposits and mention the physical features, climate, labor and living conditions. Property and ownership are outlined, the history and production of the property stated briefly, and the ore deposits are described. The work done by the Bureau of Mines is explained and supported with maps, sections, and assay logs.From March 1, 1944, to June 1, 1944, 179 wagon-drill holes totaling 3,490 feet and 4 test pits totaling 75 feet were completed, and from November 1947 to February 1948 seven churn-drill holes totaling 2,488 feet were drilled and sampled. Metallurgical tests are summarized and referenced.With respect to this report, special acknowledgment is due to J. H. Hedges, chief, Tuscon, Ariz., Branch, Mining Division, and to W. R. Storms, engineer in-charge of the Silver City, N. Mex., field office. Acknowledgment also is due to J. Bruce Clemmer, chief, Tuscon Branch, Metallurgical Division, for analyses done in the last phase of this project, and to Dr. Vincent Kelley of the Federal Geological Survey for his cooperation during this work.The Capitan iron deposits are in secs. 10, 11, 13, 14, and 15, T. 8 S., R. 14 E., central Lincoln County, N. Mex., as shown on figures 1 and 2. The only known large deposit upon which the Bureau did development work lies around the common corner of secs. 10, 11, 14, and 15, as shown in figures 2 and 3, and just southwest of and in the foothills of the Capitan Mountains. This range of mountains trends east and west. The elevation of the highest peak is 10,205 feet.The deposits are reached by traveling on State Highway 48 from Capitan north for 4 miles, to a point just inside the Lincoln National Forest fence and thence due east over a poor dirt road for 1.2 miles. Just over a small wooden bridge, the left-fork is taken, and the poor road is followed to the deposits, a further distance of 1.1 miles (see fig. 1). This road follows the fence to and through the Davis ranch. All the roads from Capitan to the deposits are dirt roads but are impassable only for short periods during and after heavy rain or snow."

Aug 1, 1949

By R. R. Sayers

The hazards connected with work under abnormal air conditions are becoming of increasing importance from a financial as well as a physiological stand- point, due to the extension of compensation laws to include diseases caused by dusts, toxic gases, and abnormal temperatures and humidities. The United States, with the excention of California, North Dakota, Wiscon- sin, Massachusetts, and Connecticut, is the only English-speaking country to-day where silicosis is not compensated.3 Cases of permenent total disability or death due to silicosis mar aprear in common-law courts, particularly in the States that have not recognized silicosis as an occupational disease for which compensation should be provided. Such cases have recently been tried in one State, according to a magazine editorial, not providing scheduled commensation for employees affected by silicosis, with results favorable to the claimant. Clearly established cases definitely linked with occupation as the cause may be expected to be recognized as deserving by juries and courts, and awards will be made. In one Atlantic Coast State, according to this editorial, 108 claims for silicosis, including 21 deaths therefrom, are said to have been filed against two small plants engaged in finely pulverizing quartz sand.

Sep 1, 1932

By Bunting S. Crocker

Pebble grinding was used at Lake Shore Mines in 1949. A full description of experimental evidence and test plant results was published in 1952 1 and further operating details in 1954.2 In more recent years the term autogenous grinding has been coined and is now frequently seen in the technical literature. Autogenous crushing and/or grinding covers any grinding mill in which the larger of ore are made to grind the fine pieces; the crushing and grinding may be either dry or wet. This discussion deals only with wet autogenous grinding, and only in the fine grinding part of the circuit, i.e., from 6 mesh to 92 pct -325 mesh. The term pebble milling could apply to fine autogenous grinding in which the pebbles are made from the ore itself, or it could also refer to grinding with pebbles, such as flint pebbles, from a source outside the mine.

Jan 5, 1959

By Shahé Shnorhokian

Remnant pillars evolve towards the latter stages of mining in an orebody and act as repositories of mining-induced stress. It is therefore crucial to plan ahead as to their dimensions and location with respect to the local geology. A case study of a Canadian base metal mine was examined for the planned mining sequence scenario to identify the stress regimes acting on a future remnant pillar occurring between levels 4800 and 5100, near a brittle dyke. A mine-wide model was constructed in FLAC3D and input parameters included results from field measurements of the direction and magnitude of the principal stresses, and the geomechanical properties of the different formations. Prior to the study, the model was calibrated based on a 6-year record of mining-induced seismicity and rockburst events, focusing on large event clusters. The mining sequence followed at the mine was then used in the model to study the planned future extraction program around the remnant pillar. It is shown that the distance of the remnant pillar from the dyke and another orebody plays an influential role on the stress levels developed in the pillar.

Jun 1, 2012

By D. A. Singer, J. C. Griffiths

"One of the most useful approaches to a complex problem is to model the system which gives rise to the problem and to perform simulations through the model to find appropriate solutions. The Engel Model may be used as such a simulator to investigate the problem of the exploration for natural resources.The Engel Model is based on a two-stage search procedure in which a known area (A) which contains m prizes is subjected to search by n coverings. During the first-stage search the sensor system records signals which may be a response from prizes (that is, true signals) or may be false. Signals tend to cluster around a prize and a cluster size consists of s signals. If a circle of radius R is drawn around each signal some will overlap and the overlap from s signals contains a prize. The cost of a single covering in which each point of the area comes under observation once, is designated E1. Second-stage detailed search is expensive and is confined to areas of overlap of s circles; it leads to the location of prizes. Second-stage search of the whole area costs Ea units. The expected value, V, of a prize is known and its development cost is E3 units.The sensor system characteristics are defined by the circle of radius R around a signal, which should be small compared with the total area A and enters the model as a parameter a x R2/A. The probability of a false signal during a single covering of a circle of radius I is a known constant, A.This model was applied to the search for uranium ore bodies using two different types of occurrence. In the first, the Wyoming Basin type, the area is relatively large (A = 1 496 square miles) and a few (m = 4) large prizes occur (expected value V = $30 million). In the second area, which represents the Ambrosia Lake region of New Mexico, the area is smaller (A = 212 square miles) and contains many (m = 200) smaller prizes (expectedvalue of a prize V,$2 million). The three costs, E1, E2, E3, are adjusted to the different circumstances in the two areas.Simulations were performed using n = 1 to 40 coverings with cluster sizes s = 0 to 19; the radius R was varied from 0.52 to 3 miles (and, therefore, a = 0.002 to 0.133 0, respectively, dependent on the area of interest). The value of A was varied from 0.01 to 0.10.Profitable programs were found over a wide range of the parameters; the two areas required different strategies to achieve maximum profit. In the Ambrosia Lake region a few passes (n = 4 to 6) with small cluster sizes (s = 2 to 6) are more profitable, whereas in the Wyoming Basin region a large number of passes (n = 35 to 40) and cluster sizes of s = 5 to 10 are most profitable.As pointed out by Allais (1957) the larger prizes are the most important in deciding the successful outcomes of exploration programs, and the profit margin in the search for a few large prizes is sufficient to yield success over a wide range of programs. Such programs require very large investments if they are to be successful.To refine the Engel Simulator as a decision-maker in selecting the most profitable exploration programs it is necessary to obtain firm estimates of the sensor system characteristics, that is, of R, a and ? (lambda)."

Jan 1, 2014

This: symposium was sponsored by the Bureau of Mines, U.S. Department of the lnterior, in order to critically examine the state-of-the-art of sulfide flotation chemistry and to define current and emerging problems that should be emphasized in future fundamental research. The topics covered through invited papers include both reviews and recent research results in the areas of thermodynamics of reagent-mineral interactions; collector adsorption processes; the effects of solid-state point defects on flotation; activation and deactivation phenomena; the electrochemical role of oxygen in sulfide flotation; environmental problems in flotation; and selective flocculation of fines. Papers riving perspectives on flotation research in relationship to our national mineral requirements and the relationships between industrial flotation research and academics are also presented. An edited summary of the symposium follows the papers.

Jan 1, 1980

1. Domestic Production and Use: In 1979, 12 companies operated 32 primary aluminum reduction plants, with 3 firms accounting for 64% of production. Washington, Oregon and Montana accounted for 32% of the total production; Gulf Coast States 20%; other Northern States 32%; and other Southern States 16%. Based on published producer prices output of primary metal in 1979 was valued at over $6 billion. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1979, building accounted for about 24%; packaging 23%; transportation 22%; electrical 11%; consumer durables 8%; and other uses, 12%.

Jan 1, 1980

Jan 1, 1991

By Grant R. Brown

This report presents the results of a study examining the relationship between supervisor characteristics and performance in underground coal mines, The specific objectives of the research include; document tasks performed by first-line supervisors during a normal shift; explain why supervisors carry out their duties as they do: identify salient characteristics of effective first-line supervisors; and formulate criteria for selecting and developing candidate supervisors. To accomplish the study objectives, on-site observation and data collection was carried out at 13 underground mines in Illinois, Ohio, and Pennsylvania. One hundred thirty-eight first-line supervisors were observed during a full work-shift and discussions with the supervisors and the mine superintendent were held during the course of the visit. The observational data from the study provide a detailed description of what supervisors to during their shift. The report begins with an introduction discussing the problem being studied and objectives of the research. The literature related to supervisor selection is then reviewed. The following section describes the research design including data collection procedures and statistical methodology used in the study. The next sections present the analysis of mine, section, crew, and supervisor characteristics. The report concludes with a discussion of the results of the study and recommendations concerning supervisor selection and development.

Jan 1, 1987

By J. C. Bothan

A program to provide technical in-formation on the use of fuels in pyro-metallurgical processes, from the Canadian fuel viewpoint, was initiated about five years ago by a Canadian Institute of Mining and Metallurgy liaison grou1> composed of members from the Coal Research Committee of the Coal Division and the Iron and Steel Committee of the Metallurgy Division. This paper is another of a series prepared for this program. Previous papers included a review of pyrometallurgical processes of Canadian interest, a survey of ferrous processes relevant to the development of an integrated steel industry in western Canada and a survey of the fuel requirements of the non-ferrous metals industry in Canada. It is widely recognized among per-sons familiar with the Canadian coal industry that, because of the large resources of coking coal in western Canada, the

Jan 1, 1963

By J. D. Bardill

"The Stoddard mine, Cheshire County, N. H., was explored by the Bureau of Mines in 1944 as a source of the strategic fluorite. It was reported that the vein persisted in the bottom of old workings and the geology of the immediate area indicated the possibility of finding additional lenses.In its program of exploration of mineral deposits, the Bureau of Nines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts pre¬liminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director.Special acknowledgment is expressed for the cooperation and assistance given by Robert F. Sherwood of the United Feldspar & Minerals Corp.; by McHenry Mosier, chief, College Park Division, Mining Branch, who aided in re¬vising this report; and by J. B. Zadra, chief, College Park Division, Metallurgical Branch, and others of his staff, who assisted in performing the beneficiation tests and analyzing samples. The field work was under the direction of Harry P. Hermance.The property lies on the southern boundary of the town of Westmoreland, Cheshire County, N. H., at approximately 72° 39’ west longitude, 42° 27’ north latitude, in the Keene, N. H. (G.S.) quadrangle.Good gravel roads lead from paved State Highway 63 to the property. A dirt road in fair condition suitable for truck leads to the nine.Dwight H. Smith, Putney, Vt., is the owner and has leased the property to the United Feldspar & Minerals Corp., 10 East 40th Street, New York 16, N. Y.Property titles were not investigated.The fluorite deposits of Cheshire Count', H. H., have been known for many years, being reported by Jackson, (Geology and Mineralogy of New Hampshire, by Charles T, Jackson, 1844) and by Hitchcock, in1878 (Geology of Now Hampshire, vol. 3, 1878, by Charles H. Hitchcock). A large pit on the largest or east vein was mined by Lovat Frazer from about 1908 to 1917, This operation is reported to have produced approximately 3,500 tons of fluorspar. In 1917, the American Steel & Wire Co, took over the mine end is said to have produced 3,500 tons of fluorspar before relinquishing the lease in 1923.From 1935 to 1937 the New Hampshire Fluorspar Cc. operated the Stoddard mine, working chiefly on the most westerly of the three known veins on the property, as well as doing some preliminary work on the small central vein. In 1938, the United Feldspar 6 Minerals Corp. leased the mine, and less than 100 tons of fluorspar was produced from exploration and development work, No mining has been done since that time."

Sep 1, 1946

This report is in partial fulfillment of Contract S0241051 awarded to COMINEC on June 27, 1974. 'Me purpose of the work under this contract is to develop a conceptual design for an automated longwall mining system. The conceptual design will serve as the basis for future design and development of an automated longwall mining system capable of sustained production in excess of 2,500 tons per shift with reduced manpower which will ultimately be demonstrated in an area where conventional longwall mining has been successful. 1.2 DEFINITION OF THE PROBLEM 1.2.1 Why An Automated System The most obvious benefit of automation and remote control in a longwall mining system is the reduction of accidents consequent upon a reduced working force in the hazardous face areas. However, another important aspect of the problem is the skilled labor shortage which is being compounded by the need for vastly increased coal production. The United States coal mining industry had a working force of almost 600,000 miners in 1928 but was able to muster only 145,000 miners in 1970. The miners required to staff the additional working sections and the new mines necessary to meet our energy needs are simply not available. Only automation and remote control will permit a reduced work force with increased production by keeping the face equipment operating continuously.

Jan 1, 1975

By S. Burks

This paper develops the themes explored by the authors at the Fourth International Platinum Conference,. Optimization techniques can be used to significantly increase the value of mining businesses by enabling better long-term planning decisions. Open pit and underground mine design, mine scheduling, cut-off grade and blending, stockpiling, and the linking of these to flexible elements of the metallurgical recovery processes are all evaluated together. Transport or sale of intermediate products and the requirements of the product metal markets can also be considered. Experience shows that net present value (NPV) can potentially be increased by 5-35 per cent or more, usually even before the expenditure of significant amounts of project capital. The case studies presented include: > An existing operation with multiple open pits and PGM concentrators linked to offsite downstream processing facilities, and with infrastructure constraints for which the scheduling of current operations and the potential for expansion were investigated > An existing operation with an integrated portfolio of mines, concentrators, smelter, and refinery, for which the various possible sources of ore for processing were prioritized to match the downstream process plant constraints and the product markets > An underground operation in Zimbabwe for which the optimum mining width was calculated and expansion plans were evaluated > An underground mine with many separate mining sections, for which a revised schedule was developed aiming to keep the shaft system and processing plant at capacity with the highest net value material available at any time throughout the life of mine. In the concluding section of the paper, a few brief notes are included suggesting how the strategic recommendations from enterprise optimization studies may be implemented by the owner's team.

Jan 1, 2013

By BUREAU OF MINES

In 1948 the United States became a net importer of oil. Coupled with an unpre- cedented domestic production of 5,900,000 barrels daily, imports approximating 500,000 barrels made available a total supply of 6,400,000 barrels a day. Thus, by herculean effort, the oil industry was able to meet an extraordinary demand at home and, in addition, to ship abroad almost 400,00 barrels daily of petroleum and products. The country's oil position now differs greatly from that prevailing at the be- ginning of World War II. Then, actual oil production averaged about 4 million bar- rels a day, and productive capacity probably was greater than 5 million barrels a day. As the demand of the military and industrial machine grew with the rising tempo of the drive toward victory, the United States not only met its own needs but pro- duced about two-thirds of the total oil requirements of the Allied Nations, excluding Russia. As a people, we can be deeply grateful that the Nation's petroleum resources were adequate and sufficiently developed to support such a tremendous effort. Even in those critical hours when immediate needs were the paramount issues, a prudent Congress paused to contemplate the importance of an assured long-term supply of liquid fuels. From these deliberations came the Synthetic Liquid Fuels Act of 1944, which authorized research and development work on new sources of oil coal, oil shale, and agricultural and forestry products. ce World War II, a civilian demand for 6 million barrels of petroleum prod- ucts has become the order of the day every day. By drilling as many as 39,000 new wells a year, the production rate has been increased enough to meet domestic require- ments by a bare margin. Some imports were necessary, however, to fill both domestic and foreign demands, and these doubtless will increase. Is this policy of exploration within the United States and the development of oil in foreign countries adequate insurance for the fulfillment of our future national needs? This question has two aspects one purely civilian and economic in character and the other significant from the standpoint of our national defense. There are now approximately 4,000 producing oil fields in this country. At first thought, it would appear that production could decline in a considerable number of these fields without materially affecting the over-all daily output. However, 48 percent of the oil comes from only 111 major fields which contain 50 percent of the total proved domestic reserves. It is apparent, then, that the flow from large fields - having proved reserves of 100 million barrels or more each must be sustained if daily production is to be kept at the present levels. Essentially, this means that new major fields must be discovered about as rapidly or perhaps more rapidly than the older ones lose productive capacity. From 1940 through 1947, only eight major fields with estimated reserves of more than 100 million barrels each, were discovered and proved - an average of one such field a year. The total estimated reserve of these eight fields was less than 1 year's supply at the present rate of use. As drilling continues, some existing fields ultimately will prove reserves larger than those now known. Without a pronounced increase in the num- ber of major discoveries, however, the prospects for increasing our present productive level are not encouraging. Any gap that appears between domestic productive capacity and demand could be filled with supplies from proved oil resources abroad. Assuming cheap pipe-line and tanker transportation to the United States, freedom from exorbitant taxes and charges

Jan 1, 1949

By Albert Ladd Colby

A GLANCE through the Bibliography appended to this paper will show that the Transactions of this Institute contain what virtually contitutes a history of the development of the manu¬facture of steel rails in this country and abroad. It is, therefore, fitting that this paper, bringing one branch of this important subject down to date, should be here presented, and it is also appropriate to select this joint meeting of our Society with the Iron and Steel Institute to compare the specifications covering the rails produced in these two countries, and to propose a standard specification to govern the manufacture of American rails for export. During the last ten years the production of Bessemer steel rails in the United States and Great Britain has amounted to 32,128,720 gross tons. Nearly 19,000,000 tons have been rolled in the past five years. The next five years will see an even larger output, owing partly to the extension of railway projects in the Orient, in South and Central America, in Mexico, and in Australia and the other British Colonies. Of late years, the American rail-mills have so largely increased their daily output, that trade conditions have often made possible the delivery of American rails to foreign ports. The tenders submitted by American mills, however, have always been accompanied by requests for changes in the foreign specifications, chiefly in the reduction of the amount of testing required; and it has only been natural, especially at first, that the engineer, whose specification had always been accepted without question by British mills, should interpret American tenders 'as an evidence that an inferior rail would be furnished

Sep 1, 1906

By A. Jakobsson

Studies of the rate of interdissolution in oxide systems in the solid state are of importance in materials processing through the powder-metallurgical route. As there is a need for following the rate of the such reactions continuously, a new method based on high temperature X-ray diffraction was developed. Mechanical mixtures of the oxides were placed in a high-temperature X-ray diffraction unit and the changes in the intensity and position of the peaks with highest intensity for both the components were followed as functions of time. A suitable theoretical model has been developed in order to interpret the experimental data and evaluate the diffusion coefficients. The method was applied in the case of the system MgO-NiO. The results obtained are compared with those obtained by another new method, based on solid-state galvanic cell technique with calcia stabilized zirconia electrolyte, developed in the Department of Theoretical Metallurgy. The advantage of the present techniques to monitor the progress of the reaction continuously make them suitable for computer control of such processes.

Jan 1, 1995

By M Pyle, R Ch, G Lane, ramhan

Data is the most valuable commodity in the information age. The use of data enables productivity, opportunity, and safety in various sectors and industries. In the late 1950s, Alan Turing coined the term artificial intelligence (AI) to describe the ability of computing machines to think and behave like humans through simplified reasoning and logic (Turing, 1950). This concept of mimicking human behaviour is the building block of machine learning algorithms used in most AI software. The ‘learning’ aspect in machine learning requires data, that is, information on the environment or the objective, to be modelled or predicted using AI. An AI-enabled system aims to predict the unknown faster and intuitively. Intuition in software algorithms can be described as probabilistic, learned through the data that the AI system is trained on; indeed, the AI software cannot predict the future, but it can provide the likelihood of an event/action occurring, thereby enabling decisions or responses to prevent it or take action. Just as various industries have adopted AI as the tool of choice to seek new opportunities (examples: medical research, self-driving cars, financial modelling), the mining industry, too, has been receptive to embracing AI for problem-solving and maximising the value of its business.

Sep 1, 2024

By P. K. Chatterjee, G. D. Just

Sublevel open stoping is a low-cost method that has been successfully employed in many large underground mining operations. Where ore body characteristics are suitable, extensive mechanization and the use of large-scale stoping techniques can considerably reduce operating costs. However, careful long-term planning of mine layouts and large capital commitments in development are required prior to production. Implementing precise mine design procedures and carefully controlling operations can result in considerable benefits. This article describes methods to achieve these objectives based largely on mining operations at Mount Isa, where sublevel open stoping has been used since 1932. Ore won by this method accounted for a very large percentage of the total tonnage produced at Mount Isa. Major costs associated with sublevel open stoping can be classified as drilling, explosives and charging, and LHD costs. In this article, analyses of these costs are made with particular reference to stope design. Parameters such as burden, drill hole diameter, explosive density, specific charge, etc., are considered in establishing the interrelationship of unit operating costs, as well as total costs of sublevel open stoping.

Jan 10, 1981

Numerical models play a significant role in the design of safe underground mining excavations and support systems. Advances in the capabilities of numerical modeling software, together with ever increasing computational speeds, have made it possible to investigate the very nature of the large-scale rock mass and its response to mining excavations. The improved understanding of the rock response obtained from modeling enhances our designs, resulting in greater stability and safety of the mining excavations. To help advance the state of the art in this field, the National Institute for Occupational Safety and Health organized the International Workshop on Numerical Modeling for Underground Mine Excavation Design. The workshop was held in Asheville, NC, on June 28, 2009, in association with the 43rd U.S. Rock Mechanics Symposium. The proceedings include 10 papers from leading rock mechanics and numerical modeling experts in the United States, Canada, Australia, and Germany. The papers address a wide range of issues, including various numerical modeling approaches, rock mass modeling, and applications in coal and metal mines.

Jun 1, 2009