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By R. B. Rao, B. Das, J. K. Mohanty, D. S. Rao

Physical, mineralogical and geochemical characterization, along with some beneficiation approach to pre-concentrate the Ni content of the chromite overburden material of the Sukinda Valley, India, have been carried out in detail. Mineralogically, the overburden consists of geothite, quartz, hematite, magnetite and secondary silicates in varying proportions. A specific Ni mineral phase is absent in this material with the Ni and Fe being mostly enriched in finer fractions. Distribution of Ni and Fe in various size fractions and increase of Ni with increase in Fe (goethite content) indicate that goethite is the major Ni-bearing mineral phase. Quantitative estimation of goethite from chemical analysis and weight loss data indicates that the goethite quantity varies from 40% to 90%. Electron microprobe analysis (EPMA) indicates that Nirich and Ni-poor goethite are present in the overburden material. A sequential dissolution study indicates that more than 50% of the Ni are present within the goethite lattice as a lattice substitution. The results of pre-concentration studies (size classification, gravity, flotation and magnetic separation) indicate that Ni is richer in finer fractions. Further, the enrichment of Ni content is limited to 1.1% with 50% recovery by classification followed by hydrocyclone separation of the below 53 m m fraction.

Jan 1, 2000

By S. L. Huang

The location and shape of potential failure surfaces in soil slopes were directly determined based on the stresses induced in the soil mass and the strength of the soil itself. Stress calculations were carried out by the finite element method with the Drucker-Prager nonlinear material model. The Mohr-Coulomb failure criterion and Mohr's circle stress analysis were then applied to the calculated stresses to determine the characteristics of the failure surface.

Jan 1, 1989

By Hugh S. Spence

IN MAY, 1930, G. LaBine and E. C. St. Paul, prospect¬ing round the southeastern shore of Great Bear Lake, in the North West Territories of Canada, discovered pitchblende at what is now LaBine Point. At the same time, they also found native silver in a small sheared break on an island lying off the point. Late in 1930, samples of the pitchblende were sent to the Mines Branch, at Ottawa. The material consisted of several fair-sized slabs of botryoidal pitchblende banded with a brownish quartz. A small amount of chalcopyrite was visible as small particles and fine veinlets, and the pieces were rather heavily stained a yellowish-green by secondary copper-uranium salts. Analyses were run in the Mines Branch Ore Dressing Laboratories on two samples, and small-scale concentration tests were made on one of them. The results of this work were published in a Memorandum Series report (No. 48) of the Mines Branch, in March, 1931.

Jan 1, 1932

By S. H. Ash

THE information obtained by examining and analyzing the core drillings from 15 diamond-drill holes shows that with the proper equipment little difficulty should be experienced while sinking the shafts at the 15 selected sites. Although a number of holes penetrated formations containing a high percentage of silica,, the health hazard from dust can be removed by using proper dust-control equipment. Methane was detected in small amounts in only one (hole 5) of the boreholes. The methane hazard should present no difficulty if adequate ventilation is employed while sinking the shafts.

Jan 1, 1952

By Shelby Z. Palya

"INTRODUCTION The Bureau of Mines was established in the public interest to conduct inquiries and scientific and technologic investigations concerning mining and the preparation, treatment, and utilization of mining substances; to promote health and safety in the mineral industries; to conserve material resources and prevent their waste; to further economic development; to increase efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting those industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the Bureau to ""disseminate information concerning these subjects in such manner as will best carry out the purposes of this Act.""In accordance with this directive, the Bureau reports the findings of its research and investigations in its own series of publications and also in articles that appear in scientific, technical, and trade journals; in proceedings of conventions and seminars; in reference books; and in other non Bureau publications. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make the kind of list and index presented in this special publication both necessary and valuable. This issue describes reports and articles published during the period January 1, 1975, to December 31, 1979. It supplements the 50-year list of Bureau publications issued from July 1, 1910, to January 1, 1960; 2 the 50-year list of articles by Bureau authors published outside the Bureau from July 1, 1910, to January 1, 1960; 3 the 5-year lists of publicatioll3 and articles, from January 1, 1960, to December 31, 1964,4 from January 1, 1965, to December 31, 1969,5 and from January 1, 1970, to December 31, 1974; 6 and the annual lists of Bureau publications and articles from January 1 to December 31, 1975,7 from January 1 to December 31, 1976,8 from January 1 to December 31, 1977,9 and from January 1 to December 31, 1978.10"

Jan 1, 1980

By G. W. Adams

Foreword While the literature on radium is voluminous, there is no single publication available from Canadian sources which attempts to cover at all fully the world radium industry. The comparatively recent developments in the Wilberforce area, and the consequent arousal of public interest in radium, seemed to call for the publication of such a paper which would be intelligible to the layman. To satisfy this apparent need, the writers submit this paper which contains material derived from various sources, and for which the writers make no claim of originality. Direct references are made throughout the paper to sources of information.

Jan 1, 1931

The wealth of a nation can be measured many ways, but one of the most important measures is its natural resources, particularly minerals. Minerals provide the foundation upon which economic prosperity and defense preparedness rest. Assessing our energy and mineral resources and assuring their development is in the best interests of all our people continues to be an important national goal. Since its founding in 1910, the U.S. Bureau of Mines has established itself as the world's premier minerals information and research agency. Its authoritative, comprehensive data and pioneering research have contributed significantly to a strong U.S. mineral position in the world.

Jan 1, 1990

By Jennifer Riefenberg

Research efforts by the U.S. Bureau of Mines include running a series of displacement-discontinuity, boundary-element models to simulate the gateroad design at an underground coal mine in northwestern Colorado. The initial mine design is a yield-abutment chain pillar arrangement in a three-entry, longwall gateroad system. Pressure effects from mining the first and second panel were recorded using borehole pressure cells (BPCs). These field data were then compared directly to the model output. Observed yielding in the field was approximated by reducing material property values and/or removing pillar elements in the model. Model results using this calibration technique mirrored the field measurements consistently. Using the calibrated model parameters, a suite of models was run simulating an experimental entry design: exchanging the yield and abutment pillar locations. These model results reflect a 20¬to 33-percent reduction in core stresses in the yield pillar during mining of the second panel. Improved pillar and entry conditions are suggested by these predictive results. The design modifications were then implemented at the mine along a 150-m (500-ft) test section. Field observations and measurements from the experimental design test site compared favorably with trends of the model predictions.

Jan 1, 1993

"INTRODUCTION Industrial utilization of the present submarginal domestic manganese resources of the United States is wholely dependent at this time on the electrolytic manganese process established as the result of 4 years of continuous operation of the Bureau of Mines pilot plant at Boulder City and 7 years' operations of the Electro Manganese Corporation commercial plant at Knoxville, Tenn.Three Kids ore provided the feed for the Boulder City pilot plant during 3 years of operation. Hence, the electrowinning characteristics of the ore have been thoroughly established, making possible accurate estimates for commercial operations.Before the Defense Plant Corporation constructed the leaching plant, the Bureau of Mines conducted an exploration project to determine the extent and grade of the ore reserves. Additional exploration, development, and mining by the Manganese Ore Cc, have accurately determined the tonnage and grade of ore. A large tonnage of stock piled ore is now available for immediate processing, and a considerable tonnage of openpit ore has been stripped of overburden preparatory to mining. Numerous facilities, such as power, water, and housing, needed for an electrolytic manganese plant are already available.All of these factors, as well as plans for installation of scale electrolytic manganese plant facilities, are presented in detail in the chapter entitled, ""Mining and. Electrolytic Reduction of use from Three Kids Manganese Mine."" The Manganese Ore Co. kindly provided information on the present ore reserves and state of development of the mine."

Jun 1, 1945

By William Gleason

The mining industry is under immense pressure to not only meet increasing demand for minerals, but to do so in an environmentally safe and sustainable manner. Growth in electric vehicles, battery storage, renewable energy infrastructure and data centers to power artificial intelligence (AI) has led to an unprecedented demand for minerals such as copper, lithium, rare earth elements and others. The need for these minerals for national defense has only increased the pressure on the mining industry. Increased geopolitical tensions between the United States, China and Russia has added a sense of urgency as supply chains have become a focal point for the U.S. Department of Energy (DOE) and Defense (DOD) and other government agencies. The International Energy Agency (IEA) predicts that copper demand is expected to grow by 50 percent by 2040 while demand for lithium could increase eight-fold by 2040 and demand for nickel and cobalt could double. The challenges to meet the increased demand include technological, workforce, exploration and environmental issues. From Feb. 22-26, the global mining industry will converge on Salt Lake City, UT for the MINEXCHANGE 2026 SME Annual Conference & Expo where these challenges and others will be addressed by some of the leading minds in the industry. Included in this year’s conference is the Resilient Energy in Mining Symposium, a symposium with input from across SME that looks to address some of the most significant challenges the industry is facing. “Adopting environmental, social and governance (ESG) best practices has become a necessity for the mining industry, not an option. The Resilient Energy in Mining Symposium is crucial for MINEXCHANGE 2026 because it addresses the complex challenges of transforming traditional mining operations to support a sustainable and secure energy future,” Lisa Gonzales, principal engineering at Arcadias and MINEXCHANGE 2026 SME Annual Conference Chair and chair of the Resilient Energy in Mining Symposium said. “Mining is inherently energy-intensive, yet it is also foundational to the global energy transition, supplying the critical minerals needed for renewable technologies. By bringing together industry leaders, the symposium fosters collaboration and actionable change, showcasing advancements and real-world solutions that demonstrate the tangible benefits of resilient energy strategies. This unique forum enables knowledge sharing, inspires innovative thinking, and helps set the standard for sustainable practices across the sector.” The symposium was created in direct response to a SME member survey in 2023 conducted by the Responsible Mining and Underground Construction (RMUC) Strategic Committee. “The survey highlighted a strong demand for technical resources on energy transition, carbon reduction, renewable power, climate change, and ESG reporting,” Gonzales said. “To address this, I collaborated with RMUC to engage committee members from all SME Divisions, ensuring a diverse and comprehensive platform that reflects every aspect of mining. We intentionally structured the symposium to centralize key content and minimize duplication across divisions.”

Jan 1, 2026

By Richard B. Stein

Section 25 has been assembled to give the geological, mining, or metallurgical engineer an overview of some of the important downstream operations that typically follow mining activities. This subject is obviously too broad and complex to be covered in detail within this Handbook. However, the engineer will be interested to learn about the basic fundamentals, and especially how they might affect the economics of the total project from prospecting and mining through to metals recovery and marketing. In this way, it is hoped that the engineer will have a better overall appreciation for the technical and commercial prospects of a mining and metal-producing project.

Jan 1, 2008

By Clyde Sitterud

Presentation Agenda ?Global Mining Tire Demand ?What is driving it? ?Latest Situation ?How long it will last? ?Michelin?s Response to Increase Supply ?New plant ?Additional presses ?Recommendations for Mining Users ?Treat tires as your major assets ?Areas of attention that will produce immediate results

Jan 1, 2005

By Mark Aylmore, Guy Deschenes

"Increasing pressure are motivating the gold mining industry to develop a substitute to cyanide for leaching gold. This effort in mainly based on the high toxicity of cyanide and on the lack of efficiency of cyanide in the treatment of mildly refractory gold ores (sulfides and pre-robbing). Consequently, in only a few years, consortia have been created to elucidate and implement a new technology. The most promising lixiviant that has been selected to replace cyanide is thiosulfate. This paper will present a critical analysis on the latest developments in thiosulfate leaching and illustrate the potential and limitations of the technology with experimental data. Finally an assessment of the cost and performance of thiosulfate leaching relative cyanidation will be evaluated.INTRODUCTIONConcerns regarding the toxicity of cyanide and inability of cyanide solution to effectively leach some carbonaceous gold ore or mild refractory gold ores have made the gold mining industry evaluate alternative lixiviants to leach gold. This concern has been heightened recently by the cyanide spill at a mine in Romania, which devastated a 250-mile stretch of the Danube River and its tributaries, and the environmental damage at Ok Tedi mine in Papua New Guinea. Some countries and locations have prohibited the application of cyanidation to recover gold, such as, California and Colorado States, Japan and Turkey etc.There are several potential non-cyanide lixiviants (Sparrow and Woodcock, 1995) for gold extraction, such as thiosulfate, thiourea and halogen. A pilot feasibility test (Marchant and Broughton, 1987) had suggested that thioureation might result in acutely toxic byproducts even after treatment. Scientists of Swedish Academic of Sciences reported that thiourea is a carcinogen. Halogen is also a pollutant to the environment. Thiosulfate leaching appears to have very good potential as an effective and less hazardous procedure for gold and silver extraction from auriferous ores. In addition to being much less toxic and relatively cheap, it forms a stable anionic complex with gold but is less reactive to other metals, for instances, copper and carbonaceous materials, in comparison with cyanide."

Jan 1, 2001

By Gabka T., R. E. Gregorczyk

Work to improve employees' behavior in Głogów Copper Smelter began in 2009. It has been noted that over 90% of accidents at work are attributable to human reasons. At that time, a series of external workshops was contracted based on exercises conducted by a psychologist trainer with supervisors. Having trained about 300 employees, an observation of employee behavior at workstations was started as part of the control of risk reduction measures. As a result of the above actions, the number of accidents was reduced by half between 2009 and 2017. Currently, internal workshops for communication improvement for behavioral auditors are conducted by the employees of the Smelter. Named: "I observe, react and communicate" and aimed at further mastering the elements of the safety culture in Głogów Copper Smelter. INTRODUCTION KGHM Polska Miedz is an integrated mining and smelting copper producer based in Poland and operates on the international metal market. KGHM, with annual production of over 500 thousand tonnes of copper, holds a middle position in the world ranking of copper producers. At the same time, in Europe it is the largest producer of copper from its own ore deposits, possessing its own integrated production structure, from underground mining operations to final, top-quality product. It is also worth mentioning that KGHM Polska Miedź is one of the largest Polish exporters and, apart from copper, is a significant primary silver producer in the world. The mission of our company, consistent with its strategy, is to produce copper and silver in a safe mode for workers and the environment, with reduced environmental impact. Therefore, "Głogów" Copper Smelter operations are continuously focused on the creation of safe working conditions, and minimizing the negative effects on the environment. The company meets the requirements of an Integrated Management System comprised of the following: Quality Management System ISO 9001:2008 Environment Management System ISO 14001:2004 OHS Management System according to the requirements of BS OHSAS 18001:2007 Being a proud socially responsible company, we are aware that part of an efficient OHS system is to recognize, monitor, prevent, educate and motivate, thus continuously improve working conditions for 2500 employees of Głogów Copper Smelter &Refinery. We clearly communicate that a low accident rate is beneficial for both, staff and the company, and is of utmost importance as a part of our health policy.

Jan 1, 2019

By Robert C. Hickman, Xavier B. Starnes

"The general location of the Kentucky, Fluorspar District and the Moore Hill fault area are shown in figure 1. An engineer3/ the Bureau of Mines visited the district in July 1942 and reported on the Moore Hill fault system. Subsequently the Bureau explored the Summers, Pepperbox, McCune, Eagle-Watson, Henry Watson, Davenport, Felix Tyner, and Eagle-Wring prop¬erties by core drilling. These properties and the principal faults are shown on figures 2 and 3.Collaboration of the Federal Geological Survey4/ was of great benefit, particularly in mapping the properties, determining the stratigraphy, and furnishing information on that and other geologic factors.Fluorite was noted as early as 1818 near Shawneetown in southern Illinois.5/ In 1835 an attempt was made to work deposit in Crittenden County, Kentucky, but interest centered chiefly upon the galena found with the fluorite. The first shipments of fluorspar from Kentucky wore made in 1373 from the Yandell mine of Crittendon County.6/ It is not known when the first work on the Moore Hill fault was done, but it seems probable that the Cullen-Eagle and Nancy Hanks were being ,worked in 1900. Gravel spar was found on the surface at the Two Brothers mine in 1904,7/ and the main shaft was started in 1914; work also began at .the Davenport in 1914, and in 1917 the Eagle-Watson was in production. A shaft was gunk on the Pepperbox in 1918, and in 1922 fluorspar was found and work was started on the Summers property. In 1924 work began at the McCune, Felix Tyner, Eagle-Wring, and probably the Hicks properties.No Good approximate record of production from each property on the Moore Hill fault system is obtainable, but an estimate based upon all data available is as follows:"

Sep 1, 1946

Jan 1, 1998

By Arcy, D&apos Banister

The productive potential of the Nation's principal active and inactive silver mining districts has been evaluated, using 1964 economic conditions and assumed silver prices ranging up to $3 per ounce. On this basis, the United States has an estimated 5 billion ounces of unmined silver, excluding minor byproduct silver in gold deposits. Approximately 3.5 billion ounces are contained in deposits requiring higher silver prices to be economically minable, and about 1.3 billion ounces are in currently operating mines. An analysis of silver consumption trends since 1954 indicates that the free world industrial market will climb to nearly 800 million ounces annually by 1985. U.S. industrial silver consumption has been projected to increase at an annual rate of 4 percent from 1965 to 1985. Average annual increase for the remainder of the free world has been 8.1 percent since 1953; this is expected to level off with an estimated average increase of 5 percent to 1975 and 4 percent from 1976 to 1985. Foreign silver production has, in the past, exceeded consumption, but in 1960 the supply deficit was over 100 million ounces. U.S. production, also traditionally exceeding demand, was suddenly overtaken at the start of World War II. By 1964 the annual deficit, excluding coinage, was over 84 million ounces. World coinage requirements of silver are fast declining and expected to total only 25 million ounces annually by 1985. In fact, coins are already becoming major short-term source of silver to fill the large deficit between industrial demand and current production. The larger, long-term deficit (to 1985, the limit of this study) must be balanced by silver from the hoards and new production from silver deposits. Eventually all of the deficit must be met by new production or silver prices will rise until consumption is greatly curtailed. To balance free world supply and demand, it is estimated that the free world must produce an additional 85 million ounces by 1975 and 375 million ounces by 1985. The estimated proportion expected from U.S. deposits is 17 million ounces by 1975 and 74 million ounces by 1985.

Jan 1, 1969

By J. J. S. Sebastian

The process development described in this report was carried out at the Morgantown Station of the U. S. Bureau of Mines in cooperation with West Virginia University. An experimental laboratory-scale pilot unit to gasify coal dust in entrainment was constructed on the Campus of the University in Morgantown. The enormously accelerated demand for liquid and gaseous fuels and utilization of our immense coal resources require that a low-cost process be developed for the gasification of a wide variety of coals. Such a process would be a major factor in lowering the cost of synthetic liquid fuels. None of the proc3sses developed in Germany prior to and during World War II, such as the Winkler process, the H. Koppers dust gasification process, the Wintershall-Schmalfoldt process, etc., meet all the requirements for a low-cost process under American conditions. Nor has any other process designed and experimentally operated at atmospheric pressure during the post-war period in this country appeared to fulfill all of the necessary conditions for a low-cost process.

Jan 1, 1950

By Paul M. Hall

In the last several years, the coal mining industry has made significant changes in the design of longwall mining systems to make them more productive. Some changes, such as increasing the length of the coal faces and increasing the capacity of the face conveyors, have resulted in problems with achieving sufficient motor torque to start and operate the longwall face conveyors. Other changes, such as increasing the size and/or decreasing the percent impedance of longwall power center transformers, have resulted in problems with the short-circuit currents on the transformer secondaries exceeding the interrupting ratings of the molded case circuit breakers used to protect the secondary circuits. A survey of 24 longwall mining systems in northern West Virginia was conducted to investigate both problems. The results of the survey are presented and analyzed. Several recommended solutions to the problems are presented to enable the coal mining industry to design safe and productive longwall mining systems.

Jan 1, 1982

By Paul M. Godlewski, Joseph P. Gildner, David S. McAllister

With construction underway on the 22.5 km (14 mile) Initial Segment of the Link Light Rail transit system in Seattle (including the one-mile EPB-driven running tunnels and mined station at Beacon Hill), the Sound Transit Board on May 20, 2004 voted on selection of a preferred route for an approximately eight-mile extension northwards from the central business district to Northgate, and authorized immediate start of advanced conceptual/preliminary engineering and geotechnical exploration programs scheduled to be completed in Spring 2005. The extension includes approximately914 m (30,000) route-feet of bored running tunnels, a mined station with platform level approximately 60 m (200 ft) below grade, three (possibly four) cut-and-cover stations and a cut-and-cover cross-over structure, as well as an aerial terminal station at Northgate and other line-section below-grade and aerial structures. All tunneling will be in glacial soils.

Jan 1, 2005