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By Reginald Dias

Mining equipment life may be extended through preventive maintenance and the proper application of quality lubricants. There are several practices mine operators should consider implementing to preserve their equipment. An exercise in review — Begin by reviewing original equipment manufacturer (OEM) recommendations regarding servicing and maintenance intervals for each part of the equipment, especially the engine. And the verdict is — If the manufacturer’s recommendations have been followed, good. If not, owners/operators should begin periodic service work on equipment, to help minimize equipment downtime and extend engine life.

Jan 1, 2004

By T. R. Ellis

The valuation of mineral properties in the U.S. is only partially regulated. The regulations which have jurisdiction or impact appear to have such mainly as a consequence of unintended fallout, since the regulations were designed for other purposes. Court case history can also be important. The combined results are a mixture of bad and good, with important lessons to be learned. Since 1981, the Securities and Exchange Commission has prohibited U.S. listed companies from reporting quantitative estimates of mineralization and the value of mineralization, other than proven and probable reserves. This results in the minerals appraiser (valuator) working with a shortage of data in his everyday work, both on the subject property and in sales analysis. Between 1989 and 1995, all 50 states and essentially all federal agencies adopted the Uniform Standards of Professional Appraisal Practice (USPAP) for real property appraisals (valuations). The major national appraisal societies also require their members to abide by USPAP. A significant portion of minerals appraisals must now follow these standards. This paper will discuss the content of USPAP. It provides a very good framework for the valuation of a minerals property or a mine, both as real property and as a business. However, the credentialing standards for real property appraisers are now prohibitive for minerals appraisers.

Mar 1, 2002

By T. R. Ellis

"The valuation of mineral properties in the U.S. is only partially regulated. The regulations which have jurisdiction or impact appear to have such mainly as a consequence of unintended fallout, since the regulations were designed for other purposes. Court case history can also be important. The combined results are a mixture of bad and good, with important lessons to be learned.Since 1981, the Securities and ExchangeCommission has prohibited U.S. listed companies from reporting quantitative estimates of mineralization and the value of mineralization, other than proven and probable reserves. This results in the minerals appraiser (valuator) working with a shortage of data in his everyday work, both on the subject property and in sales analysis.Between 1989 and 1995, all 50 states and essentially all federal agencies adopted the Uniform Standards of Professional Appraisal Practice (USPAP) for real property appraisals (valuations). The major national appraisal societies also require their members to abide by USPAP. A significant portion of minerals appraisals must now follow these standards. This paper will discuss the content of USPAP. It provides a very good framework for the valuation of a minerals property or a mine, both as real property and as a business. However, the credentialing standards for real property appraisers are now prohibitive for minerals appraisers."

Jan 1, 2002

The Bureau has published much data on sulfur (4, 15, 23)3, most of it dealing with national or international aspects of the sulfur industry. Little information, however, is available on sulfur marketing in specific States or areas, Therefore, the Bureau has conducted a survey of the resources, production, consumption, and economic future of the sulfur and sulfuric acid industry in States of the Central and Southern Rocky Mountain area - Wyoming, Colorado, Utah, Arizona, and New Mexico - and in the Northern Plains States - North Dakota, South Dakota, and Nebraska, even though these States do not represent an economic or marketing unit. The purpose of this survey is to review the demand for sulfur and primary sulfur compounds that draws upon the natural resources of the region, to discover opportunities for better use of these resources, and also to analyze and evaluate the patterns of consumption, sources of supply, and other factors that affect the demand for these mineral products. While this survey stresses the economic and marketing phases of the industry, a complementary report (32) emphasizes the resources of sulfur in Wyoming, Colorado, Utah, New Mexico, and Arizona.

Jan 1, 1962

Summary of the morning's events with a Written Contribution to Paper No. 4 and author responses

Jan 1, 1947

By A. El-Midany

Dolomite impurities are increasing in the currently mined phosphate deposits in Florida. Several research efforts have been conducted in various laboratories around the globe to find methods to economically removing the dolomite. However, a universal and cost-effective process is not now in commercial use. In this paper, a new process for dolomite/apatite separation is presented. The differential solubility of dolomite in slightly acidic solution is utilized to generate micro CO2 bubbles at the dolomite/water interface. Particle (dolomite)/bubble aggregates float to the surface leaving phosphate concentrate with low MgO content. Interestingly, up to 6.0 mm particles can be floated by such micro-bubble/particle aggregates. Different surface-active agents were tested to stabilize the bubbles. Results of these tests are presented, and the mechanisms involved are discussed.

Jan 1, 2009

By Foster Fraas

One of the lithium minerals most widespread in the earth's surface is spodumene (Li20-A1203-4Si02), a lithium aluminium silicate. For some time, deposits of this mineral were known to exist in the Black Hills of South Dakota, but it was only quite recently that Hess4/ pointed out the great magnitude of the low-grade deposits in forth Carolina. The theoretical lithia (Li20) content of spodumene is 9.04 percent. The only other minerals with such high lithia content are the phosphates, but these occur only in pockets and are not in extensive deposits5/. Actually, however, the lithia content in spodumene is never found to be this high, being nearly always below 7 percent for the pure mineral, and part of the lithia is apparently replaced by other alkalies.

Jan 1, 1937

By J. J. Gusek

There are hundreds of passive treatment systems accepting mining influenced water (MIW) throughout the world. Some systems do not perform to design expectations while others, including volunteer systems, have successfully operated relatively unattended for decades. The primary reasons for this situation include the common misconceptions that (1) a “cookbook” approach to design is valid for a wide array of MIW chemistries and site conditions, and (2) low maintenance means “no maintenance.” Passive treatment systems for MIW are typically manmade ecosystems that are designed to handle a specific range of metal loading conditions and MIW geochemistry. Thus, when design conditions are exceeded, the suite of microbial to macroscopic ecosystems may be slow to recover or mature. This should be no surprise to designers. But when a particular system fails, it may be inappropriately attributed to the technology, not the design. This paper presents a standard “phased” design protocol that appears to work and provides examples of sub-par performance of selected passive treatment systems.

Jan 1, 2002

By R. A. Beall

Consumable-electrode arc melting is now accepted throughout the industry as the best method for producing ingots of zirconium, titanium, molybdenum, and their alloys. In addition, the technique is widely used in laboratories for fusing samples of such metals as hafnium, chromium, tantalum, columbium, and thorium. The production of consumable electrodes from these metals presents some rather difficult problems, the accepted industrial solution being the use of heavy powder-metallurgy-type presses. This paper summarizes information on fabrication of consumable electrodes by this and alternative means, such as sintering, nippling, and welding lightly pressed compacts of scrap metal. A possible saving of considerable capital investment is shown in the case of sintered compacts. The electrical circuit components of a pilot sintering unit are analyzed. INTRODUCTION The consumable-electrode arc-melting process has been accepted by most of the industry as the best method at present for producing high-quality pure or alloy in-got from sponge titanium or zirconium. This technique is not particularly new, having been patented by Von Bolton (l)3/ in 1909 for melting tantalum. However, it has been applied to industrial-scale operation only in the last few years. Among the important contributions to this technique are the work of Kroll (2) and Parke and Ham (3) and the work reported by the Office of Naval Research (4). The Bureau of Mines-has added considerably to the knowledge of this process (5-9).

Jan 1, 1956

Drilling at Ipswich during the last twelve years by the Queensland Department of Mines has proved large quantities of reserves which have assured the security of the field for many years to come. This is perhaps the greatest contribution to the development of the field since its discovery in 1827.The drilling campaign commenced in 1950 and by the end of 1961 comprised 242 holes totalling 180,220 ft.Intersections of formations and seams, accompanied by detailed surface mapping, led to more precise knowledge of the geology of the field than was previously possible, and clarified many problems of correlation. Productive formations are part of the Middle Triassic Ipswich Coal Measures, a 4,300 ft sequence of fresh-water sediments with some interbedded volcanics. They are overlain by the Upper Triassic Bundamba Group and the Lower Tertiary Booval Group.Reserves disclosed by drilling amount to 171,487,000 tons, comprising 109,407,000 tons "measured" and 62,080,000 tons "indicated". The security of these reserves encouraged many collieries to instal modern efficient mining machinery and washing plants.The climax of recent development of the resources of the field will be the commissioning in 1966 of a £33 million 360 MW power station in the Swanbank district which will consume 14 million tons of coal during its 30 year life and will have a peak demand of some 20,000 tons per week.Drilling is continuing and is expected to prove additional reserves which will justify further development of the field.INTRODUCTIONUntil 1949 there had been no concerted effort to test systematically the resources of the whole Ipswich field. Fifty two known holes totalling 30,500 ft had been drilled, eight of them by the Department of Mines, but because of poor core recovery and inadequate records most of them were of little use in a comprehensive assessment.Development of the field was being retarded by uncertainty regarding reserves and by the general state of the coal mining industry. Numbers of comparatively small independent companies and owner groups were operating coal...

Jan 1, 1963

By D. E. FOCG, A. E. Wells

When the United States entered the World War governmental agencies found little definite knowledge available as to the exact capacity of each sulphuric acid plant in the United States to manufacture acid under the stress of a great emergency. It is true that on account of the demand for acid for the manufacture of munitions for the Allies, prior to the entrance of this country into the war, most of the acid plants near industrial centers in the Eastern and Northern States were running at or nearly their maximum capacity, but, . for various reasons, many plants in these States and plants in other districts were not. For a number of years statistics as to the production of acid by the plants of the country were compiled by the United States Geological Survey, but obviously such figures did not give information as to the maximum capacities that might be available for meeting the he.a vy war ·requirements, or as to the steps that would have to be taken to bt-ing these capacities into use. During the summer and early fall of 1917 various attempts were made to obtain the desired information, but no satisfactory or complete data were obtained. Late in 1917, under the authority granted to the Bureau of Mines by the explosives act, the Director of the Bureau of Mines directed A. E. Wells, metallurgist of the bureau, to uiake a complete survey of the situation. Mr. Wells personally conferred with officials of the acid companies and visited most of the acid plants in the North that are east of the Mississippi River. The information obtained through this personal survey, together with that obtained through the ready cooperation of the subcommittee on ncids, and the subcommittee on fertilizers of the Committee on Chemicals of the Council of National Defense, enabled the preparation of a report containing the desired data concerning the sulphuric acid industry. This report was made immediately available to the War Industries Board and to those offices in the War and Navy Depart- ments that were most directly concerned in planning the explosives program and in obtaining the necessary supplies to produce the explosives. Beginning with this survey and report, the sulphuric acid section of the war minerals investigations of the Bureau of Mines took an active part in all matters pertaining to the sulphuric acid industry during the remainder of the war. Mr. Wells, the chief of the section, was appointed an associate chief of the sulphur, pyrite, and sulphuric acid sections of the War Industries Board. .Also, by this direct contact with the War Industries Board, the data obtained by Messrs. R. R. Hornor, H. A. Buehler, a.nd 0. Lindstrom, who were in charge, for the bureau, of the investigations concerning the supplies of pyrite and sulphur, were constantly made available to all interested Government agencies. D. E. Fogg, of New York City, was appointed chemical engineer to the sulphuric acid section to make special investigations relating to the acid industry, especially the possible utilization, in an emergency, of those sources of raw material.not then being used. Mr. E. E. Corbett, of Brooklyn, N. Y., was appointed chemical engineer to make investigations concerned primarily ,vith the conservation of acid. Direct and intimate contact with the industry was had through the close cooperation with the committee on acids of the Chemical Alliance, this committee during the greater part of 1918 occupying rooms with the acid section of the bureau. With the ending of the war and the close o:f the active work of the acid section of the bureau, the suggestion was made by many interested parties that a bulletin be prepared giving some qf the fun. damental and most important facts regarding the sulphuric acid industry, including a discussion of the technical :features of the manufacture of acid. During the war the bureau received -a vast number of inquiries in regard to various phases of the industry, a.nd this fact also made such a bulletin seem desirable. Therefore, the present bulletin was prepared to cover the main facts in regard to the industry in this country, including a discussion of the supplies of sulphur-bearing raw materials, the situation of the acid plants, the principal points in regard to manufacturing processes, and the uses of the acid. No attempt has been ma.de to discuss at length the manufacturing processes, as details differ more or less at the different plants and in general are carefully guarded by the acid ·companies. A great deal of the data given in this bulletin may be found in various pub]ications, but this is the first publication in which such data have been assembled and made readily available. Most of the data were obtained directly from observation and from cooperating acid companies or from individuals who had been or are now engaged in acid manufacturing and were liberal and generous in making their information available for publication. Care has been exercised to publish no data that were obtained as confidential by the bureau's representatives. The average acid manufacturer may be already more or less acquainted with most of the information presented in this bulletin, yet it is believed that the bulletin will be of value to those who wish to obtain a. general review of the present condition, both the economic and technical, of the sulphuric acid industry in the United States.

Jan 1, 1920

By Chas. F. Jackson

INTRODUCTION This paper is one of a series dealing with mining methods and costs, prepared and published under the sponsorship of the US Bureau of Mines (USBM) and made possible through the cooperation of many mining companies in the US and foreign countries. The data presented have been obtained from papers previously published by the Bureau dealing with indi¬vidual mines, from the technical press, and from infor¬mation furnished by the mining companies. DEFINITIONS Top Slicing The term top slicing is commonly applied to that method of mining in which the ore is extracted by a series of timbered slices, beginning at the capping; the slice is caved, bringing down the capping to the floor of the slice; the succeeding lower slices are mined up to the overlying mat or gob, consisting of an accumulation of timber from the upper slices and broken capping, which follows the mining progressively downward (Fig. 1). The term has also come to be applied to the mining of ore bodies only one slice thick, by a series of tim¬bered slices one beside the other. The timbers are blasted out, bringing the capping down to the floor, suc¬ceeding slices being driven alongside those already caved (Fig. 2). In USBM classifications of mining methods, top slic¬ing has been placed under the heading caved stopes. The method differs fundamentally, however, from the cav¬ing methods of mining in which the breaking of the ore itself is accomplished by caving action induced by undercutting. In top slicing the ore is broken by the ordinary methods of drilling and blasting, and only the capping is broken up by caving. Main Levels or Haulage Levels Main or haulage levels are the main extraction levels on which the ore is hauled to the shaft. These levels and the shaft constitute the preliminary development of the mine.

Jan 1, 1982

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

By C J. de Beer

The Kwaggashoek East pit is one of the four production areas of Thabazimbi Iron Ore Mine. The Kwaggashoek East Open pit mines through the abandoned sublevel caving operations of the Kwaggashoek East underground workings. A risk assessment indicated that the primary risk is the occurrence of surface subsidence. Based on local knowledge, a hypothesis, that most of the cavities were filled with broken rock as a result of roof collapse and bulking of failed material was formulated. To test the hypothesis a number of geophysical methods as well as probe drilling was utilized. The results of the resistivity, gravity and ground penetrating radar surveys were inconclusive in determining the position of voids. Either there were no voids present or the resolution of the surveys was not high enough to pick it up. It is accepted that only small voids remained, and that the supported roof hypothesis is valid. As a precautionary measure all the production blast holes within the caving area were over-drilled by forty percent. This would collapse the roof of any small voids or tunnels immediately below the block. This operation proved to be successful as two of the three underground levels have been mined out with no subsidence occurring in the pit floor.

Jan 1, 2006

By Gene R. Reid

The contract objective is the development and in mine testing of an Automatic Fire Control System (AFCS) for mobile underground metal mining equipment. The effort described by this report covers the period from June 21,1975 through June 30,1976 and accomplished the following tasks: ? Preparation of Data Handling Plan and data acquisition which included visits to twenty mine sites in eleven states, visits to Bureau and MESA facilities, and a literature survey. ? Data analysis which determined the most hazardous type of vehicle for use in the demonstration, and design requirements for the AFCS, ? Development of recommended design concepts for the AFCS. ? Design and development of the AFCS including tests on a full-scale mock-up of a load-haul-dump (LHD) vehicle. ? Underground fire tests on an ST-2B-LHD vehicle at the Hecla Lakeshore mine Casa Grande, Arizona.

Jan 1, 1976

By R. Webber, D. Averill, L. Whittle, D. Moffeti, G. Kassakhian

"This paper describes the recent pilot-plant work carried out on two alternative processes capable of producing an effluent containing less than 10 pCi/L total radium-226 activity and very close to 3 pCi/L dissolved radium-226. The processes incorporate coprecipitation of radium with barium sulphate by the addition of barium chloride in continuously stirred tank reactors followed by either chemical coagulation with ferric chloride, flocculation and clarification, or polymer-aided dual-media filtration. IntroductionUranium mines in Canada have practiced radium removal from tailings basin effluents since 1965. Treatment consists of addition of barium chloride to precipitate radium as barium- radium sulphate and provision of natural or constructed settling ponds for sedimentation. This process, however, has been identified as being deficient in that it allows particulate or suspended radium-226 releases which are higher than the regulated dissolved values». Also, the large size of some of the settling ponds is believed to represent a real limitation of the present technology because of inferred difficulty in recovery of barium-radium sulphate precipitates.The Federal Government Mining Task Force established a Radioactivity Sub-Group in 1974 to assist in the development of effluent regulations and guidelines for the uranium mining industry. Among the recommendations of the Sub-Group was the need to seek more effective methods of radium removal, including development of physical/chemical treatment systems as an alternative to settling ponds. In response to the SubGroup recommendations, a bench-scale study began in March 1976at the Wastewater Technology Centre (WTC) of Environment Canada . The results of this study indicated that coagulation and flocculation of the precipitate from barium chloride addition is a viable alternative to sedimentation in settling ponds(3). The bench work was expanded and accelerated in 1977, with financial assistance provided by the Atomic Energy Control Board. Subsequently, a research program with a larger scope was developed; this program is jointly managed and funded by government and industry, as shown in Table I.One of the goals of the joint program is to develop, at pilot scale, a physicalI chemical process to reduce the radium-226 content of uranium mining and milling effluents. Target radium-226 activities for treated tailings basin effluents were set: namely, 10 pCil L total and 3 pCil L dissolved radium 226. Extensive bench-scale and pilot-scale work was conducted through 1978 and 1979 and has culminated in the development of two physical/chemical processes. This paper describes work carried out at a pilot plant which led to the selection of the two physical I chemical processes for demonstration. In short-term tests, the processes produced effluents meeting the radium-226 target activities."

Jan 1, 1980

By Edward L. Beutner, Robert M. Crump

Benson Mines low-grade iron ore reserve is a replacement deposit within the Grenville gneisses of the Adirondacks. The average grade of the crude ore is about 23 per cent iron. The iron minerals are principally magnetite and hematite disseminated throughout the gneisses as discrete grains about 1 mm in size. Both the ores that are beneficiated by magnetic means and the non-magnetic ores that are treated by a gravity method of concentration are found in stratigraphically different positions but are mined from one open pit, which is about 2.5 miles long and 800 feet wide and are treated separately. The gneisses are described and named according to the distinctive mineralogy of each. Recognition of the gneissic types permits the interpretation of the structure as a northward-plunging syncline overturned to the west. A large subsidiary anticline-syncline complex occurs on the east limb of the major syncline. Iron minerals in sufficient quantity to be considered ore are confined to areas where the footwall rock has been overturned to become the hanging wall.

Jan 1, 1968

NASA has received direction for lunar habitation beginning in 2024. Prior to then, it will be necessary to learn about how lunar soil can be used to promote civilization on the moon. Questions must be answered: ?Will it support plant life?,? ?Can it be used as a construction material?,? ?What is needed to maximize health and safety?,? and ?Will it affect equipment, tools, machinery, and clothes?? The only samples available for study came from the Apollo Missions. Because the expense of bringing more material back to Earth is prohibitive, there is not enough available to perform studies to answer the above questions. Hence, there is a great need for its synthesis. Most efforts to date have concentrated on making ?simulant? from single natural resources of volcanic rock. However, another possibility is to use resources here on Earth to extract the minerals of interest into concentrates or so-called ?separates? using traditional mineral processing techniques, and then mix the separates in appropriate ratios to simulate the lunar soil. In this paper, results from a study in which dry Road Norite outcrop and wet mill tailings from the Stillwater Mining Company?s Concentrator located near Nye, MT were examined. Of course, the in-side challenge is to make ?separates? from gangue minerals.

Jan 1, 2012

By John S. Alexander