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By F. E. Cash

The Holmes Safety Association was organized and named in honor of the late Dr. Joseph A. Holmes, first director of the United States Bureau of Mines. The association is a national organization and operates through local, sectional, or State chapters in mining, petroleum, and allied industries. The National Council of the Holmes Safety Association consists of representatives of State councils and local chapters, with the Director of the Bureau of Mines as president.

Jan 1, 1929

By CHARLES M. A. STINE

THE value of chemical research has been so thor¬oughly demonstrated in the last few decades that the general public has become "research-conscious" to an extent which allows the advertising agent and publicity man to make use of research as a selling point in his advertising campaigns. We thus see the advertisements of concerns in the most varied industries stressing the research which is back of their products. The reason for this "research-consciousness" of the general public. is primarily that the products of research have increasingly engaged public attention and have. revolutionized our daily life. When we. reverse the flight of .time and imagine ourselves-in the century previous to our own, we find that we are .without the automobile, the radio, the improved telephone and electric light, refrigerated transportation, the airplane, X-rays, and many other things now taken for granted. A generation ago we find gloomy prophets foretelling the certain over-population .of the world within a few decades and an insufficiency of food due to lack of the fixed nitrogen which is now so plentifully ours.

Jan 1, 1930

By Arthur Mackwell

The role of the precious metals is changing rapidly. They are becoming primarily materials of modern industry, and their decorative and monetary functions are diminishing in relative importance. Certainly gold is still the premier metal for jewelry, as silver is for silverware. But these uses are not growing nearly so fast as are the uses of these metals in a variety of industries. This is even more true of the platinum metals. Moreover, this is true despite the fact that the precious metals are highly expensive and liable to substitution by the base metals in cases where this is feasible. For the fact is that the physical and chemical properties of the precious metals make them relatively invulnerable to substitution; where they can be replaced by the base metals, they have been, and the opportunity for further substitution is, therefore, limited. SILVER In November 1969 the United States Treasury stopped minting the only remaining coin with any silver content. That was the silver-clad Kennedy half dollar, which had a silver content of approximately 40%. The step was taken out of necessity, because of the rising shortfall between world mine production and consumption. It was important to divert the 35 to 40 million oz of silver per year used for the minting of this coin into the open market, where it would be available for industrial consumption. This decision was important, not only for its practical effect but also for what it symbolized. Only four years earlier, in 1965, the Treasury had used 320 million oz of silver" for the full range of coinage. Now not an ounce of silver goes into the United States coinage. The reason is simple and yet complicated. For many years the U.S. Treasury had purchased silver at prices which provided a subsidy to domestic producers. As a result, silver producers were eager to sell to the Treasury, and that agency built up a huge supply of the metal -almost 2 billion oz by- 1961. But, as the free-market price neared $1.29, the basic melt value of the coinage, the Treasury became a seller of silver, not a buyer, and its stock was depleted rapidly. The Treasury lost more :than a billion ounces of silver in the years 1962 through 1965, and it continued to lose silver, both through coinage and through sales to consumers, through 1969. The Government continued to sell silver to consumers at the rate of 1.5 million oz a week, even after terminating the 40% silver Kennedy half dollar. But it was apparent that the Government stocks could last no more

Jan 1, 1976

Jan 1, 1991

By A. Shaak

The town of Hedley is some 200 miles due east of Vancouver and lies in the bottom of the Similkameen River valley, at the junction of Twenty Mile creek, at about the 1,700-foot elevation above sea level. The Nickel Plate mine camp is on Nickel Plate mountain at an elevation of about 5,600 feet, four miles slightly east of north from Hedley, to which it is connected by 9 miles of road, and by 10,000 feet of tramway and electric railway. The latter is used both to transport the ore to the 275-ton mill at Hedley and to furnish the mine with supplies. History The Nickel Plate claim was staked in 1898 to cover the sole outcrop of the Nickel Plate system of orebodies. Soon afterwards it was optioned by the Marcus Daly interests of Butte and underground exploration commenced. Early exploration was successful, and a power plant, tramway, and mill were constructed. The mill began operations in 1904. Production under Daly control ensued from June, 1904, to August, 1909, and amounted to 167,000 tons. The Hedley Gold Mining Company was organized and commenced operations in 1909. The capacity of the mill was increased by stages to 200 tons and a steady production, except for short periods in winter, was maintained until 1930. By 1930, gold to the value of nearly $10,000,000 had been produced since the discovery in 1898. The South American Development Company optioned the property in 1932. Active exploration was conducted during 1933 and 1934 by the Kelowna Exploration Company, a subsidiary of the South American Development Company. This work was sufficiently successful that, coupled with the increase in the price of gold from $20.67 to $35.00 per ounce, production re-commenced in December, 1934, and continued uninterrupted until July, i946, when, along with all B.C. gold mines, a strike closed operations. Under the present ownership, the mill capacity was increased to 275 tons.

Jan 1, 1946

By P Myers, T Elkington, S Wonday

Sierra Rutile LimitedÆs (SRL) heavy mineral sand mining operation in Sierra Leone, West Africa, is embarking on a new phase of its life. After confronting many challenges during the 1990s and 2000s, SRL is embarking on a strategy of growth to recover maximum value from the mine over the rest of its life. Sophisticated linear programming techniques have been used to develop an optimum strategy for extracting SRLÆs many known deposits of economic grade, while considering options for expansion and for a variety of mining and processing methods and combinations. CITATION:Myers, P, Elkington, T and Wonday, S, 2012. Strategic optimisation at Sierra Rutile - A case study in maximising project value, in Proceedings Project Evaluation 2012 , pp 59-66 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By Northcutt Ely, Charles F. Wheatley

This chapter deals with the systems of laws by which governments regulate the exploration for and production of the minerals within their jurisdictions. It is a summary, restricted by necessary space limitations, of material assembled by the author for a forthcoming publication of the United States Bureau of Mines, "Summary of Mining and Petroleum Laws of the World." (Information Circular, 1959.) The present study is organized in three parts, dealing with (1) the historical background of these legal systems, (2) laws of the United States, and (3) laws of other countries of the world. The reader's attention is invited to the acknowledgments at the end of the chapter, which inadequately express the appreciation due those who have assisted in the collection of this material. Part I. Historical Development of Major Western Systems of Land Tenancy with Respect to the Ownership and Control of Minerals The use of metals in primitive societies was largely confined to the manufacture of weapons for self-preservation. The ruler's control over copper, then brass, then iron, was essential to maintenance of his own ascendancy at home and his group's position against neighbors who had access to similar metals. Ancient societies were thus characterized by the ruling group's ownership of minerals and metals. The Egyptian civilization, which emerged in the fourth millenium B.C. upon the agricultural subjugation of the lower valley of the Nile, was responsible for extensive development of the upper valley as a source of mineral wealth. The production of gold during the height of that civilization has been estimated at $30,000,000 per year, thus equaling the early placers of California and Australia. The mines of Egypt were the property of the Pharaohs and were controlled at their direction. Greek mining developed a different scheme of land tenancy which more closely resembled modem concepts. Development of mineral resources was

Jan 1, 1959

Discussion of the paper of R. J. COLONY, presented at the New York Meeting, February, 1921, and issued With MINING AND METALLURGY No. 169, January, 1921. R. J. COLONY (author's reply to discussion).-The work of Sosman and Merwin on the system lime-ferric oxide, mentioned by Mr. Rankin, was not overlooked. When studying portland cements and portland-cement clinkers petrographically, however, the lime-iron compound was difficult to correlate with the very definite dicalcium ferrite described by those investigators, which possesses such well-defined optical properties. In portland cements, the calcium ferrite (or ferrate?) is an indefinite, fuzzy, and generally amorphous, or apparently amorphous substance that is distributed interstitially with respect to the other grains, from which it was very difficult to derive any satisfactory results. For this reason, the writer, tentatively, chose to regard it as related to the aluminate, and assigned to it the composition 3CaO.Fe203, which may be incorrect, however, as Mr. Rankin suggests.

Jan 8, 1921

By C. Yi, M. Onifade, B. Genc, S. Dineva, T. Zvarivadza, M. Khandelwal

Deep hardrock mines worldwide increasingly face rockbursts as mining depths increase. These events result from the accumulation and sudden release of stress, causing rockmass damage and posing major safety and operational challenges. This paper focuses on destress blasting as a critical strategy to mitigate rockburst hazards. Although limited practical experience exists in Swedish deep hardrock mines, international case studies demonstrate that, when well implemented, destress blasting redistributes peak stresses by promoting controlled fracturing around mining excavations. The success of such techniques is highly dependent on site-specific factors such as stress regime, rockmass brittleness, structural geology, and blast layout. Although destress blasting is especially effective in massive, brittle rock under high stress, typical conditions for strainburst prone environments, its design cannot rely solely on numerical models. Simulations can offer preliminary evaluation of stress redistribution trends and guide early design assessments but their current limitations, including sensitivity to input data and simplified fracture mechanics, mean they are best used as supplementary tools rather than final decision-makers. Field trials, supported by microseismic analysis and fracture mapping, remain essential for validation. The study critically synthesises international experiences and presents a structured framework for destress blasting design, offering practical and academic perspectives aligned with Swedish geological conditions to support safer and more efficient application in deep hardrock mines.

Jun 27, 2025

By W. I. Watson

The study considered all the institutional, resource reserve, technological, and economic factors relevant to the industry's present and future status, such as markets and marketing techniques, competition from other producers both domestic and foreign, federal and state regulations affecting the industry, quarrying and processing technologies, slate reserves and resources, and industry structure and economics. Constraints to the growth of the industry were assessed and scenarios proposed to solve some of the problems.

Jan 1, 1980

By George A. Mealey

Caving mining methods that are based on a planned caving of rock above and/or at times surrounding the material being mined can be classified in three broad categories: longwall mining, sublevel caving, and block caving. Each of the three methods involves a distinct technology as well as art of operation. Each requires a relatively large, regular, and predictable ore body. As a rule, the effect of mining results in some form of impact or change on the surface. Operationally, underground caving methods are characterized by high productivity as well as a high percentage of extraction of the mineral being mined. A key element for the productivity of this form of mining is the ability to standardize the various elements of work taking place underground. Therefore, work-men may perform a specialized role rather than function as all-around miners. Further, the nature of the mining methods lend them to a high level of mechanization. Operations and manpower can be centralized into a relatively small area where supervision can be concentrated and therefore be more effective. Productivity as well as safety benefits thereby. The caving method is unique in that the exploitation openings are deliberately destroyed by the process of mining. Rock mechanics principles focus on the ensurance and the propagation of the cave as well as the continuance of the mine openings designed to extract the broken ore. As a rule, production operations are designed to maintain a steady, continuous flow of ore from the extraction areas. This steady flow rather than an intermittent flow tends to promote good caving action as well as reduce hangups.

Jan 1, 2008

By AIME AIME

The first session, held Tuesday evening, February 23, in North Sheffield Hall, was called to order by Louis V. Pirsson, Chairman of the Local Committee, who introduced Prof. Russell H. Chittenden, Dean of the Sheffield Scientific School of Yale University. Professor Chittenden, in behalf of the Governing Board, felicitated the Institute on its visit to New Haven, and cordially welcomed the members and guests to the University and the city. Dr. James Douglas, who presided at the meeting, responded in behalf of the Institute. The Secretary announced that, upon the proposal of many members, the unanimous report of the Committee on Membership, and .the unanimous recommendation of the Council, the following members had been unanimously elected by the Board of Directors Honorary Members in the American Institute of Mining Engineers Prof. Richard Beck, of Freiberg, Saxony, in recognition of his distinguished service to technical literature, and the cordial

Apr 1, 1909

By Peter K. Kaiser

Planning and design of deep underground mines involves a process of complex three-dimensional data integration utilizing information from exploration (geology, rock mass characteristics), engineering (mining method, excavation geometry, stress) and operations (time, in the form of sequencing). As new logging and monitoring technologies are being developed, the amount and data complexity becomes overwhelming and decisions are often made based on only a small part of the available data. Recently, Laurentian University opened a state-of-the-art Virtual Reality Laboratory (VRL), a Mining Exploratorium that is unique in the world of mining and offers an exceptional data interpretation environment for mine planning and design. The Mining Exploratorium combines a large format spherical stereoscopic projection system, equipped with high definition projection providing the highest resolution of active stereo in the world today, with advanced features of earth modeling software. Combined, this creates the first virtual reality facility geared specifically to the interpretation of mine geometry, geology, geochemistry, microseismicity, geomechanics and mining data sets. This paper demonstrates how value can be added to the mine planning and design process by utilizing this unique tool in the mining decision-making process via better comprehension of spatial relationships of data and by interpreting the data in a collaborative immersive virtual reality environment.

May 1, 2002

By Carl Fisher

A microseismic roof fall warning system was field tested in Western and Eastern coal mines in the United States to better define the capabilities and limitations of the microseismic method in predicting roof fall. Microseismic event and energy type data were obtained and documented for twenty-three coal mine roof falls, Field test results indicate that both the microseismic event and energy methods, as applied in this development effort, have a high probability for successful application in a commercially practical roof fall warning system. Based on the results and experience obtained during field testing, a commercial prototype microseismic roof fall warning system was designed and constructed. Although it was the intent of the program to field test the commercial prototype system, delays in equipment fabrication and contract time limitations did not permit field testing.

Jan 1, 1980

By M. M. Tilman

The Bureau of Mines conducted research to determine the feasibility of strengthening experimental magnesium-base sheet alloys by strain softening induced by controlled cold rolling followed by selective heat treatment. Relatively small alloying additions having potential for producing strain softening were selected from metals that are readily avail-able. Tensile properties comparable to minimum properties of the most commonly used magnesium-base sheet alloy AZ31B, in the H24 condition (strain-hardened and partially annealed), were obtained in an Mg-IMM (mischmetal)-O.5Mn alloy after strain-softening rolling followed by heat treatment. Tensile properties of the experimental alloys in certain conditions are also compared with minimum tensile properties of other standard magnesium sheet alloys. Incidental to the principal objectives, apparent superplastic behavior was observed in three experimental magnesium-base alloys containing MM, MM plus manganese, and MM plus zirconium.

Jan 1, 1985

These proceedings consist of papers presented at three Bureau of Mines Technology Transfer Seminars on ergonomics in the mining industry. These seminars were held in December 1981, and covered topics relating to ergonomics and mining in the areas of the man-machine interface, and design of the work environment. This area of research is directed toward reducing accidents traditionally associated with human error.

Jan 1, 1981

By A. E. Soregaroli, H. D. Meade

"The Keystone porphyry molybdenum deposit, located in southcentral British Columbia, is hosted by intrusive rocks of the Cretaceous Mount Lytton batholith and the early Tertiary Keystone quartz diorite stock. The molybdenite mineralization is associated with rhyolite porphyry dikes flanking a large 1300 m by 2100 m breccia complex. Recognition of the potential for the buried molybdenum porphyry system was based on quartz-molybdenite vein fragments within the hydrothermal breccias.The full extent of the molybdenum mineralization is not known. The few deep drill holes along one comer of the breccia complex defines strong metal zoning of molybdenum and associated elements of F, Mn, Zn, Pb, Au, Ag, Fe and W about the molybdenum stockwork mineralization that may be useful for guiding additional exploration. The best mineralization occurred near the base of the deepest drill hole with 0.114% Mo in rhyolite porphyry near the edge of the breccia pipe at a depth of 1350 m.The exploration history of the deposit has been complex, focussing on both porphyry-style mineralization and precious metal veins and stockworks on the periphery of the porphyry system. Exploration to date has defined an attractive porphyry molybdenum system with uneconomic grades at great depth; however, there remains significant potential to define economic mineralization elsewhere in the Keystone porphyry system and adjoining occu""ences."

Jan 1, 1995

By K. E. Barnes

"The “Jameson Cell” flotation cell was developed at Mount Isa Mines in the late 1980’s to address deficiencies in our flotation column installations. Early base metal installations had a variable record. The test work and trials showed they made an improvement metallurgically when operated correctly, but performance of the early installations was hindered by a range of operational and maintenance issues. The installations needed to be more robust, and we needed a better understanding of how to successfully integrate the cells into the plant flow sheet.During the 1990’s, Jameson Cells had great success in coal fines flotation and organic removal in SXEW applications, and became the standard in these applications in Australia. These installations improved the cell design and materials of construction and the cell flow sheet design, to make it low wear with self-regulating control, producing good performance with little operator input.These improvements have enabled a fresh look at the use of Jameson Cells in base metals. Recent new installations have shown significant benefits in “hybrid” circuits, that combine the best features of both Jameson Cells and conventional flotation cells, achieving better overall circuit performance in a smaller footprint than either technology could do by itself.Case studies of successful base metal applications are discussed, using size-by-size mineralogical performance to explain the improved circuit performance. The new methods of flow sheet test work design are also described."

Jan 1, 2006

By Michael Amick

Due to the importance of maintaining open airways on a longwall panel, mine management decided to install cribs made of foamed cement. Foamed cement had been used at other company operations on several projects. A recent test at a sister operation had proven the crib installation technique and established that foamed cement cribs could provide better support than wooden cribs. The area to be supported was in a remote location; the limited material needs of foamed cement cribs offered a substantial advantage. In mid February 1993, 75 foamed cement cribs were installed on the tailgate of the active longwall panel. The 75 cribs resisted both horizontal and vertical stresses while successfully supporting the entry.

Jan 1, 1993

By L. P. Larson

In this Bureau of Mines evaluation of the domestic supply position of tungsten, certain tungsten resources in the United States are estimated as to quantity and grade and then are systematically costed in detail (excluding exploration costs). A supply curve is developed which depicts the quantity of tungsten (WO3) up to about 15.5 million short ton units that is producible at calculated price levels ranging from about $13 to $125 per short ton unit. About 10.4 million short ton units are available at a calculated price that is less than the present market price ($40). Total known resources amount to about 40.2 million short ton units. A very large portion of that quantity was not costed due to inadequate information on either resources or processing methods. Further exploration and research would have a significant effect on the availability of tungsten in the United States.

Jan 1, 1971