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By Will Mitchell

The classical definition of a beneficiation engineer as one who treats an ore in order to separate and discard worthless fractions by essentially physical means is obsolete. Technology in the profession has advanced so rapidly during the last two or three years that educators have not been able to coin definitions to keep up with the pace. In the past some people have hesitated to include leaching or even agglomeration as minerals beneficiation, because of the major chemical changes involved. This view has fallen by the wayside, especially because a majority in the profession have become actively involved in extraction and pyro processes that go far beyond the original definition of mineral dressing. To say that there is a great revival of interest in leaching is putting it mildly, for the uranium business, like the gold business, now depends almost entirely on leaching. This revival of leaching, long overdue in mineral engineering, has been stimulated this year, especially as a result of the relaxation of security restrictions surrounding the recovery of uranium from its ores. It has brought new unit operations to minerals beneficiation, namely ion exchange and solvent extraction. These operations have appeared as resin-in-pulp, solvent-in-pulp, and liquid-liquid systems. In many cases these leaching and separation procedures, now reaching the production stage, have been engineered by minerals beneficiators. The trend toward leaching has also had impact on the technology of beneficiating other nonferrous minerals, especially copper, manganese, columbium, tantalum, nickel, cobalt, titanium, and the rare earths.

Feb 1, 1956

By Edward Keller

The work covered by this report was undertaken at the request of Dr. J. A. Holmes, late Director of the Bureau of Mines, to whom the writer had been recommended by C. W. Goodale and E. P. Mathewson, of Butte and Anaconda, Mont. The director's offer was accepted for the honor it conferred and for the useful results that might be promulgated by the work in the technical field covered. The investigation was facilitated by permission to visit various works and sometimes by contributions of important definite information on a given subject. It is therefore with pleasure that acknowledgment of courtesies is made to the following corporations and gentlemen: Anaconda Copper Mining Co., Raritan Copper Works, Baltimore Copper Smelting & Rolling Co., United States Refining Co., American Smelting & Refining Co., B. B. Thayer, A. C. Clark, A. L. Walker, William H. Peirce, E. A. Cappelen Smith, H. H. Alexander, F. C. Newton, S. Rolle, R. "V. Deacon, N. W. Pierce, O. C. Martin, C. N. Sappington, James K Thomson, W. G. Derby, and the assistants of the writer, K. 1V.McComas and W. L. Raup. In this report considerable space has been devoted to general and theoretical principles on the ground that under modern conditions the best results in any field of activity can be attained only with the aid of an adequate knowledge of the best theories underlying the practice. The diffusion of such knowledge in the field of sampling metallic metallurgical materials appears to have been quite insufficient, and it is felt that when the principles involved are once thoroughly comprehended their universal application will be appreciated, so that it will make no difference whether pig iron or gold bullion is offered for test. It may further be noted that a discussion of the theories underlying practical methods is placed under the caption "Practical Sampling," with the idea that no one can be a practical sampler unless he is capable of analyzing his methods. No attempt has been made to advocate anyone method, but it is hoped that the analyses of all of the methods in use will show where each may be correctly and safely applied. The fact that it is possible to demonstrate the theoretical correctness of several methods indicates the invalidity of the claim that any single one of them is the standard.

Jan 1, 1916

THE first session was held in the small hall of the Academy of Music, on Tuesday evening, February 18th, 1879. The proceedings were opened by the reading, by President Eckley B. Coxe, of the following Address : SECONDARY TECHNICAL EDUCATION. Technical education is a subject to which both the American Institute of Mining Engineers and the American Society of Civil Engineers have of late years given much attention, and deservedly so. We all remember the admirable address of our former President, Mr. Holley, at the Washington meeting, upon this subject, and the very interesting reunion of the two societies in Philadelphia for its discussion. The problem to the solution of which the meeting devoted its attention was, "Shall the practical education of the engineer in the mine, in the rolling-mill, in the workshop, or in the field, precede, be contemporaneous with, or follow his theoretical studies in the technical school ?" I do not propose to add anything to what was so admirably said by so many of our leading engineers on that occasion ; but I shall ask your attention to another question in technical education, which seems to me equally worthy of our consideration, and which, I am sorry to say, has as yet attracted but little attention in this country. It is, "Shall the apprentices (I call them so for the want of a better general name), who are growing up and learning their trades in and around our mines and works, and from whose ranks the master mechanics and foremen of the future must be taken-shall they be provided with some means of obtaining as much theoretical training as may be necessary to enable them properly to understand the various processes and operations that they may be called upon to superintend, and not be obliged to pick up, as best they may, here a little and there a little truth mingled with much error?" In the former case, those who have the ability and industry to avail themselves of the advantages that should be offered to them would fit themselves to become real foremen, men who would understand and appreciate the true engineer and his methods. Of late years the young men of this country who have wished to enter our profession have had great facilities offered to them for so doing ; there have been undoubtedly great improvements in the methods of instruction; and although I am very far from imagining that no further progress can be made, or is demanded, yet I feel sure that

Jan 1, 1879

By Robert S. Young

During the last quarter-century, exploration for metallic deposits in Maine has been sporadic with peaks generally coinciding with periods of high metal prices. Known cases of regional or semi-regional evaluations are few; most efforts have been local and usually intensive. On the basis of broad geologic groups, the State has been divided into five fundamental environments: ( 1) coastal metamorphic belt; (2) southern volcanic belt; (3) Silurian slate belt; ( 4) northern volcanic belt; and ( 5) Devonian slate belt. Although not restricted to these areas, exploration in recent years has been concentrated in the northern and southern volcanic belts. Notable examples of recent exploration activity, directed to sulfide minerals, include: ( 1) the Knox County nickel-copper-bearing ultramafic rocks; (2) the Harborside (Cape Rosier) copper-zinc deposit; (3) the Second Pond (Black Hawk) zinc-copper-lead-silver deposit; ( 4) the Big Hill-Barrett lead-zincsilver- copper-gold zones; (5) the Parmachenee copper-zinc belt; ( 6) the Moxie Lake nickeliferous peridotite; and (7) the Attean quartzmonzonite molybdenum-copper occurrences. The Second Pond and Harborside prospects appear to be close to production. Systematic investigations for non-metallic deposits appear to have been aimed principally toward limestone, asbestos, diatomaceous earth, and spodumene-bearing pegmatites. Advances in prospecting methods, high metal prices, a favorable business outlook, increasing cooperation from large landholders, and some discoveries support the probability of increased exploration activity in Maine during the coming decade.

Jan 1, 1968

By M. W. BERNEWITZ

DURING my recent extended visit to Australia and New Zealand, these notes on oil and gas prospecting in that part of the world were compiled from recent reports-press and government, from conversation with one of the financial leaders in the search for oil, and from personal observation of operations of the principal importers, blenders, and distributors of oil products; also from the astonishing testimony given by them to the Petrol Commission. Australia and New Zealand have practically no petroleum production beyond a few thousand gallons a year from wells in the latter Dominion. Everything is imported, Table 1. showing the quantities for 1929-30 in Australia and for 1930 in New Zealand,

Jan 1, 1934

By Louise Corriveau, Bronwyn Azar, Valerie A. Jackson, Luke Ootes, Jeff Harris

We use the results of new bedrock mapping, combined with geochemical point data and airborne radiometric data (in particular equivalent uranium concentrations) to help determine which geological units in the Paleoproterozoic Great Bear magmatic zone (GBmz) contain elevated uranium. The data collectively indicate that the highest primary uranium concentrations are in equigranular granites and subvolcanic/volcanic porphyries. Notably, these rocks host the majority of known uranium-bearing deposits and/or prospects in the GBmz. We speculate that the uranium in these deposits/prospects was derived from nearby, uranium-enriched rocks and was mobilized by much younger, circulating hydrothermal fluids. Sedimentary rocks of the Thelon and Dismal Lakes groups unconformably overlie the GBmz and are known to host unconformity-type and sandstone-hosted uranium prospects. Most likely, the uraniumenriched rocks of the GBmz acted as a uranium donor to these overlying sedimentary basins. The method of investigation employed in this study may be applicable to other ‘granitic’ terrains in order to identify regions with favourable rocks for uranium exploration.

Jan 1, 2013

By Raymond B. Ladoo

In order to obtain comprehensive and authentic information on fluorspar mining in the western States , the writer, together with and at the request of representatives of some of the largest fluorspar producers of the Illinois - Kentucky district , spent the month of April , 1922 , in examining all we stem fluorspar deposits ( of which record was available ) believed to be of possible commercial importance .

May 1, 1923

By R. D. Mollison

"Ecstall Mining Limited was formed to operate the Kidd Creek mine, discovered by Texasgulf Incorporated in 1961 the orebody is geologically very complex, containing rich values of zinc, copper, silver and lead. The first phase of the operation involved an open pit, railroad and concentrator complex, which was under construction in 1965 and began operations in late 1966. The open pit, with rim dimensions of 2,000 by 1,000 feet, was computer-designed and highlights excellent wall control and efficient ore extraction and grade control. The railroad was built over the worst type of muskeg country, but it has been well maintained, resulting in an uninterrupted supply of ore in the trains. The 10,000-tpd concentrator, located 17 miles from the mine, is highly instrumented and automated. It features computer control of reagents and, in addition to the copper, zinc and lead flotation circuits, has a modern gravity tin plant. The concentrator is large, because very fine grinding is required for good metallurgy and nearly 2,500 tons per day of concentrates are produced. In 1969, work was started on the underground mine to take over from the open pit; it began partial production in mid-1973. The mine is highly instrumented, has a ramp from surface, a high-production shaft, an underground gyratory crusher and an efficient orehandling system, and employs the latest mining techniques. The electrolytic zine plant, rated at 120,000 tons of slab zinc per year, started operation in April, 1972, with batch leaching and purification circuits. It has been converted to continuous leaching and is now in the process of converting to continuous purification. Further modernization and automation will be carried out in the next few years. Five service departments support the five operating departments. These are maintenance, engineering and technical services, geology, administration and employee relations. How these ten departments function and work together using the most advanced technology to produce an efficient operation is the main theme of the Ecstall Story."

Jan 1, 1974

By Javier Linares García

At then end of this year will be 10 years of producing concentrate for Antamina. This is a summary of what occurred over the last decade to increase production and tonnage above the design tonnage of 70,000 tonnes per day, up to an average of 100,018 tonnes per day in 2010, an increase in production of 42.9%. Equipment currently in use is the originally installed equipment, signifying a meaningful increase in capacity without capital. In this paper, the different phases of improvements and the realization of their impacts in chronological order will be outlined. Figure 1 below shows the average daily tonnage processed each year (tonnage throughput each year/calendar days), as well as the percentage increase over the tonnage of design.

Jan 1, 2012

By I. J. Wu

China’s land area, comparable in size to United States or Canada, contains diverse geological environments and mineral resource potential. The diversity in geological environments is such that the potential for developing many world-class mineral deposits in China is good. However, China’s mining sector was not open to foreign investment until the1990s. The long-term prospect for Chinese resource development is attractive because of China’s enormous population and cumulative demand for minerals. Approximately 33 foreign mineral companies, including 11 major internationals, are to various degrees active in China. Chinese mining laws and regulations pertaining to joint ventures with foreign companies are, from the international investment prospective, evolving slowly, but positively. This positive trend is continuing under the current government reform process, which is moving China towards a freer market economy. Although improving the enforcement of relevant laws and regulations is an ongoing process, the environment for mineral investment and joint ventures is increasingly more accommodating to foreign companies.

Jan 1, 2000

Jan 1, 1879

By Christopher J. Bise

Volume II of this collection of research reports, entitled "Model Training Program," provides the framework and details for developing a tailored training program for a specific mine based upon documented human-performance deficiencies. To do this, several steps must be followed prior to program implementation: 1) background information must be gathered (database analysis), 2) direct observation of indicated problem areas should be conducted (safety sampling), and 3) separation of those deficiencies to be addressed through training from those which would be better addressed by workplace or equipment redesign (trainability assessment). Once training is determined to be the appropriate strategy for addressing the noted deficiencies, several approaches can be taken, depending upon whether the problem is related to repetitive work procedures in a predictable, a variable, or a dynamic workplace with a substantial amount of interaction between workers, equipment, and the environment. Although this volume and the subsequent seven volumes provide examples of how the training information was field tested using various strategies (for example, loss control, task training, etc.) and techniques (for example, microcomputer-based exercises, lectures, etc.), the ultimate selection of the delivery method is based on cost/benefit analysis. Therefore, the Model Training Program has incorporated a Training Cost Model as a desirable component.

Jan 1, 1993

By K. Musgrave

"The ISO 9000 Quality Management System Standards have become internationally accepted as the way to manage quality assurance. The author has developed a Maintenance Management System Standard using ISO 9001as a model and is working with a major basemetal mining company to implement this. This paper describes the structure of the standard and the steps required for its implementation.Using a management standard ensures that a system is maintained, reviewed by internal audit, and when instances of failing to follow the procedures (nonconformances) occur, that corrective action is taken. It also ensures that regular reviews are made and that the sys-tem is continuously improved.The Standard is designed so that if an organization decides to register to an ISO 9000standard, the Maintenance Management System will be in a format that is compatible and can be incorporated with little effort into the Quality System.IntroductionIn reviewing maintenance operations at many mining companies, and often seeing those same organizations some years later, two recurring issues have been noticed..The first issue is how dependent effective maintenance is upon individual supervisors and crews. In one situation, a mine that had an excellent maintenance system in the 1980s. Now, with new supervisors and crews, it is starting to develop a system that will bring it back to where it once was. No written procedures remain from the earlier excellent system.The second issue is that most operations feel that maintenance is the sole responsibility of the maintenance supervisors and crews. Nothing could be further from the truth. Maintenance, like safety, is everyone’s responsibility. If the operator does not report problems and perform daily checks, and if the production supervisor runs equipment until it fails, then nothing the maintenance crew does will prevent emergency breakdowns and lost production. More importantly, equipment will be operated in unsafe conditions, putting employees at risk and, with today’s regulations, leaving supervisors open to prosecution.The Maintenance Management System outlined in this paper is designed to establish the present best practices as standard procedures, to provide a continual review so that these practices are improved in the future, and to identify instances where the system fails so that corrective action is taken. The mine referred to above is using this approach to make sure that, this time, the system it implements will survive."

Jan 1, 1997

We are moving into an era where we experience the consequences of the skills crisis û namely many resource models have been generated by inexperienced people under pressure to deliver high quality resource estimates in unsupported environments, often without technical mentors. These resource models form the basis of our decision to pursue actual mining. This begs the question: how valid are the resource models that form the basis of our mining decisions? This paper presents various model validation tools such as comparison of input and output statistics, swath plots, sectional or bench comparisons between drill holes and models as well as a variety of other approaches. Each model validation tool currently used in industry is examined:how the tool generates results,what assumptions exist,what constitutes a pass/fail in the test, and what interpretations to consider when using the validation tool. Each validation toolÆs suitability and the inherent flaws in the underlying assumptions are also discussed. These are supported with examples of good versus bad validations. Our principles based reporting codes provide flexibility in how models are generated and what approaches and/or parameters are used to generate resource estimates. This flexibility works well when used by experienced practitioners. However, our reporting codes assume a level of experience not always available in the current skills crisis. This paper seeks to provide minimum model validation prerequisites for model acceptance and suitability, regardless of the resource analystÆs experience. As we move forward, our immediate challenge is to ensure our baseline resource models are material, transparent and competent.

Jan 1, 2009

By F. Taylor Ostrander

Some countries are infinitely poorer than others in mineral resources-despite the perfect equality of their political leaders ambitions. Compare the mineral poverty of Kenya and Tanganyika with the riches of Katanga Province and Northern Rhodesia. Compare Paraguay with Chile, There never has been any equality in the distribution of nature's wealth. Minerals cannot play any role at all in economic development where they don't exist, and there are bound to be differential rates of economic development where there are basic differences in the wealth of mineral resources available. Africa is my principal area of interest and I know that there is an unfortunate but widespread misconception about Africa's "vast mineral resources, "its "untapped mineral wealth." Why is it untapped? Why is it undeveloped?

Jan 1, 1963

By Nirander M. Safaya

Revegetation success on surface mined lands is dependent upon the nature of the plant growth media. Soil physical and chemical properties dictate the needs for specific reclamation and subsequent management practices. Field experiments were conducted at six coal mine sites in Oliver and Mercer Counties, North Dakota to determine the subsequent effects of a single application of selected amendments on spoil and topsoils over the five year period, 1974-1978. Considerable variations in the physical and chemical properties were found in mine spoils from site to site. The texture of spoils ranged from sandy clay loamy at North Beulah I to loamy at Glenharold, and from sandy loamy at North Beulah 3 and South Beulah sites to loamy sands at the Center site. The pH of the sites ranged from 6.5 at South Beulah to 8.2 at North Beulah 3. In many cases, the pH values of mine spoils were not significantly different from the topsoils. The electrical conductivity (ECe) did not exceed 6 mmhos cm-1 at the test sites even though in other studies much higher values were recorded in the same vicinity. The spoils from Glenharold and North Beulah test sites can be classed as moderately saline, and those from Center and South Beulah as non-saline. The sodium adsorption ratios (SAR) varied from less than 1 to 32, with highest values in the spoils of North Beulah 3 followed by Glenharold; all other sites were nonsodic. Lowest SAR values (less than 1) were found in the topsoiled sites at South Beulah and Center. Spoils of North Beulah 3 test site were highly calcareous, followed by North Beulah 2 and Glenharold. Center mine spoils which were the least calcareous of the test sites, showed the calcium carbonate equivalent three times higher than that of the topsoil. The average calcium concentrations in the spoils of North Beulah 3 and South Beulah test sites were -13 and 14 me 100g -l while at North Beulah 2 and Glenharold test sites 25 and 22 me 100-1-1 were recorded, respectively. The overall magnesium concentrations ranged from an average of 4 to 16 me 100g 1. Sodium concentrations in all sites never exceeded 10 me 100g-1. Phosphorus concentrations on the average at North Beulah 1, North Beulah 2, and Center were 10.2, 4.6, and 22.2 µg g -1 spoil, respectively. Concentrations of potassium ranged from 200 ppm at South Beulah site to more than 375 pp in at the Glenharold site. High concentrations of sulfates (239-2778 µg g-1) seem to contribute to the salinity in these spoils. Chloride concentrations of spoils were low and never exceeded 40 µg g-1 spoil. Based on established critical levels of deficiency for micronutrients in agricultural soils, it seems that none of these were deficient. However, controlled environment experiments did reveal increased plant growth responses when some micronutrients were added to the mine spoils. Treatment effects were highly site specific depending on the nature of the soil/spoil characteristics and, of course, the properties of the various treatments. While slack coal amendment to the spoils at North Beulah 2 site affected significant increases in a large number of variables (both major and trace elements), amendment of the topsoils at the South Beulah test site with leonardite resulted in significant decreases in a number of variables, particularly trace elements. Spoils at Glenharold and North Beulah 3 demonstrated the fewest significant changes due to amendments. Calcium, magnesium, strontium, organic matter and nitrogen were consistently increased from site to site with the addition of lignitic materials. Other spoil/topsoil physical and chemical properties (30 variables) as affected by amendments and time are discussed.

Jan 1, 1982

By Linn M. Farish

The estimated production of petroleum in the Dominion of Canada for 1931 was 1,582,000 bbl., an increase of 60,000 bbl. over 1930. Nearly all of the production came from Alberta, with a small quantity from Ontario, and a very minor amount reported from New Brunswick. At the beginning of 1931 it was hoped, and predicted, that a substantial increase in production would be shown for that year, but such was not the case, since Alberta did not show the anticipated gain. The production from Ontario and New Brunswick has not varied more than a few thousand barrels during the past 10 years and aggregated 124,000 bbl. in 1930, with 126,600 bbl. estimated for 1931. Unless new fields are discovered, production in 1932 will decline, with Ontario and New Brunswick showing little change and Alberta declining appreciably. Canadian production by provinces during the past 10 years is given in Table 1. Furnished by the Dominion Bureau of Statistics. a Barrels of 35 Imperial gallons or 42 U. S. gallons. c Figures for Ontario and New Brunswick are estimated. The production of natural gas in Canada reached the record figure of 29,377,000,000 cu. ft. in 1930 and it is estimated at 26,874,600,000

Jan 1, 1932

Executive SCOTT TURNER, Chairman FREDERICK M. BECKET JOHN A. MATHEWS H. A. GUESS WILLIAM WRAITH Finance HENRY KRUMB, Chairman PAUL D. MERICA ROBERT E. TALLY Admissions JOHN M. LovEJOY, Chairman GEORGE D. BARRON ERLE V. DAVELER WILLIAM H. BASSETT W. D. B. MOTTER, JR. Alternates HENRY B. FERNALD F. JULIUS Polls AMOR F. KEENE

Jan 1, 1932

By Louis M. Schlesinger, Michael J. Garska, Joel F. Hutwelker, James T. Jr. Tanner

A pilot plant was constructed and operated to investigate the column flotation of 20 x 200 mesh North Carolina phosphate ore, using high throughput, high solids operating conditions developed at the NCSU Minerals Research Laboratory. Flotation was performed at 45% solids in a 9.5 cm (3.75 in.) diameter by 2.26 m (7.4 ft.) tall column at throughputs of 19.1 t/hr/m2 (2.0 stph/ft2) and 31.7 t/hr/m2 (3.3 stph/ft2). Recoveries in excess of 98% of the phosphate value were obtained at the lower throughput -- while obtaining concentrate grades containing over 28% P205 (61.2% BPL) at that recovery. Recoveries of about 95% of the phosphate value were obtained at the higher throughput, while making a concentrate averaging 27.6% P205 (60.3% BPL). In addition, a better understanding of the variables governing the column flotation of coarse nonmetallic minerals was gained. Variables examined included superficial air velocity, throughput (superficial feed velocity), frother type, frother dosage, and bias rate.

Jan 1, 1993

By Richard Paul Seelig

THE following review covers published information on pressing of metal powders at room temperature. Only those operations are considered which occur between the time the powder is filled into the cavity and the compact is ejected from the die. Thus, this review does not concern hot pressing, coining or sizing feed or flow problems, commercial presses nor designs. It was also necessary to disregard to a large extent the effect of pressing on subsequent operations and on properties after sintering. The pressing operation is considered independently in its function to compact loose metal powder into useful shapes which can subsequently be handled. There are some comments by the writer in connection with a few of the findings quoted in the literature in order to stimulate thought and discussion. The selection of references quoted in the text is in some cases arbitrary although an attempt was made to favor papers containing novel ideas, techniques or results which may stimulate future research. In order to enable the reader to check further into the subjects mentioned, the original, rather extensive, bibliography is appended even though not all the references are touched on in the printed version of this review. EXPERIMENTAL APPROACH The equipment used by various workers, for example a die design created by Bridgman,22 is very interesting. The die insert has a conical external surface. The vertical pressure exerted on the punch transmits itself to the die which in turn is pushed harder into its tapered retainer. Thus, the higher the pressure exerted on the punch, the higher also the pressure exerted inwards on the die inserts. In as much as this pressure counteracts the internal pressure from the compact the two stresses balance each other so that it is possible to obtain tremendous pressures without breaking the die. The die collar was made from an oil hardening tool steel, heat treated to a tensile strength of some 300,000 psi. The die was closed at the bottom by a plug made from special tool steels. Bridgman found that there is no steel which will withstand a compressive stress of 700,000 psi without continuous slow flow or immediate fracture. Therefore, the only material suitable for use in the pressing punch was sintered carbide. In view of the ingenious design it was possible to use special tool steel as die material. Jones22 raises the question whether this method of pressing has practical application in powder metallurgy. Al- though these tremendous pressures cannot readily be utilized without many special precautions, the tapered die and retainer idea is believed to be useful even for lower pressures. Bridgman, himself,8 calls attention to the fact that the properties

Jan 1, 1947