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FRANK N. SPELLER,? Pittsburgh,. Pa.-Mr. -Hayward's paper again draws attention to the fact that copper in steel is not the enemy that a good many of us it one time thought it was. He shows clearly that steel with over 0.75 per cent. of copper is as dependable, under the :conditions which he describes, as the same steel without copper. I might add that you-can weld copper-steel- satisfactorily up to that point; in fact, we have succeeded in welding pipe by the lap weld process up to 1 per cent. copper. Notwithstanding the date that have been presented on the effects of copper on the physical properties and corrosion of steel, a maximum copper limitation is still found in many specifications. In some cases the limit is extremely low, such as below 0.05 .or 0.03: per cent., or thereabout. That is a relic of days gone by, and I think the practice should be discouraged. E. F. CONE, New York; N. Y.-Not so many years ago steel-casting makers were very particular as to the amount of copper that existed in the pig iron that they used. They would not use copper-bearing pig iron unless mixed with non-copper iron. I do not know what the practice now is in the particular foundry where I was metallurgist at one time,

Jan 4, 1918

THE following paper is a description of the plant and operations of the above company in their recovery and treatment of the quartz tailings deposited as final residues by the various mining companies. at Waihi, Karangahake, and Waitekauri into theOhinemuri River. During the past few years the silting of the Ohinemuri River has increased to such an extent as to cause considerable interest and discussion, and has lately been the subject of a most extensive inquiry by a Royal Commission, to consider the best means of dealing with what is generally spoken of as a public nuisance.Ever since the commencement of mining in this district, which was opened as a goldfield in 1875, the various mines operating have been discharging their tailings into this river, it having been proclaimed a sludge channel in 1895. Up to the year 1900 the quantity of quartz crushed was not large, probably not exceeding 500,000 tons; but since that date the annual tonnages discharged have increased enormously, and at the present time would total from 550,000 to 600,000 tons per year. Records show that up to the end of 1910 at least 5,000,000 tons have been crushed, for an actual yield of bullion considerably exceeding £10,000,000 in value, and all the valuable tailings from...

Jan 1, 1911

There are a number of different mechanisms by which wetlands can immobilise the metals in mine drainage. Here, the biogeochemistry behind four of these mechanisms (adsorption, biological uptake, precipitation as oxyhydroxides, and precipitation as sulfides) is discussed from the perspective of sustainability. Moreover, treatment wetlands are considered as part of a larger system, also taking into account the source of the drainage and various aspects of the receiving waters. The biogeochemistry of different metal immobilisation mechanisms in wetlands determines what kind of drainage can be treated with success, and it also places an upper limit on the amount of metal that can be removed from the water phase per unit of time. This has important implications for the design of treatment wetlands, perhaps particularly in colder climates. A thorough understanding of the prevailing biogeochemical processes is essential when attempting to establish treatment wetlands after the closing of a mine. If a wetland is to be used as a sustainable æwalk-awayÆ solution, the anticipated change in treatment efficiency over time (as pollutants accumulate in the system) must be considered in relation to the expected changes in drainage quality. It is also important that the total metal immobilisation capacity of the wetland is not exceeded and that the integrity of the system is maintained, in order to minimise liberation of previously immobilised metals.

Jan 1, 2003

By Oberlin Smith

The experiments described in this paper are very incomplete and only preliminary to those I hope to make in the future. Having had a good deal of experience in cutting, forming and drawing sheet-metals, and feeling a great interest in the commercially new and wonderful metal, aluminum, I applied to my friend, Mr. A. E. Hunt, for some specimens in sheet-form, that I might, from time to time, test its working-properties in presses with which we happened to be experimenting at the works of the Ferracute Machine Company. The chances for such trials being accidental only, and the time having been limited to the last few weeks, no crucial experiments have been tried, and no exact data have been obtained for a rigid comparison with other metals. The results of what little we have done, however, are shown in the articles exhibited in connection with the reading of this paper, which comprise various cups, plates, boxes, bells and cartridge-cup and shells. For the latter I am indebted to my friend, Mr. Hobbs, of the Union Metallic Cartridge Co., who, at my request, ran several pieces of sheet-aluminum through the dies with which he was making brass cartridges. The specimens are rougher than they would be had the metal not been a little too thin for the particular dies which he happened to be running.

Jan 1, 1890

By H. A. Schwartz, A. F. Gorton, H. R. Payne

In a previous paper1 we published what we believed to be a correct stable equilibrium diagram for an iron-carbon alloy containing + 1.20 per cent. silicon. The purpose of the present paper is to record the results of studies concerning the effect of silicon on the location of the eutectoid points of both systems, including also certain incidental observations of general interest. We prepared white cast irons containing roughly 21/2 per cent. carbon, 0.05 per cent. manganese, and 0.03 per cent. each of phosphorus and sulfur, but of accurately known silicon contents which varied from 0.40 to 3.32 per cent. These were completely graphitized, and both A1 points determined, as in our previous work, the specimens being converted from the stable to the metastable condition and vice versa by appropriate heat treatments. Each stable alloy was heated to a few degrees above Arl for 3 to 7 hr., quenched and analyzed for total and graphitic carbon, the difference being the "combined" or, better, agraphitic2 carbon content of the saturated solid solution just above the eutectoid transformation. One specimen was lost through accident, and the 0.40-per cent. silicon material gave an anomalous result ascribed to difficulty in maintaining the stable system in the presence of but little silicon.

Jan 1, 1923

By Carl Henrich

A.. S. DWIGHT, New York, N. Y.-Mr. Henrich's paper is rather inconclusive as to the role that alumina really plays in slags. He gives a number of interesting instances of high alumina, with conclusions that he draws from the analyses, in the light of what he knows of the accompanying conditions, but the information given is hardly sufficient to permit intelligent criticism of these conclusions, for it is well known that the slag composition is not the only factor that can produce some of the furnace results favorable or disastrous, as the case may be, which he records. As a matter of fact, most metallurgists who have wrestled with this problem in connection with the smelting of lead and copper ores, usually arrived at some sort of a working hypothesis which met the local conditions fairly well, and then, being busy men, were inclined 'to leave the theoretical question very much as Mr: Henrich leaves it when he says: "A question with which I purpose dealing at some future time." It is unfortunate that in the Golden Age of the smelting industry in the West, when we were all dealing with large tonnages of complex ores, often containing large percentages of alumina in combination with other. refractory elements, the smelting companies were not generally equipped for research as they are today, and much experience that might have been,

Jan 4, 1917

By John M. Wootten

The development of new coal markets is -t upon the ability to utilize coal in an environmentally acceptable and economically viable fashion. Foremost in the concerns about coal utilization is the impact its combustion has on air pollution. Concerns over environmental issues, such as acid rain, are currently one of the major impediments to the development of new coal markets. The Department of Energy and the Synthetic Fuels Corporation are addressing certain aspects of the development of new technologies for the utilization of coal. However, at the present time, there is a void in the new technology development process. That void is the step from proof- of-concept to commercial demonstration. Congress has established the Clean Coal Technology Fund at a level of $750 million to fill this void. The Department of Energy, in a solicitation of interest, received over 175 proposals for commercial demonstrations of clean coal technologies. A review of these solicitations indicates that $1.2 billion worth of research could be accomplished with a federal cost sharing of $425 million or 35 percent of the total. Industry has indicated, through this response, its willingness to invest its limited funds on projects it feels have the greatest potential for the clean use of coal. What must now occur is that Congress must appropriate the monies from the fund to initiate the commercialization of these clean coal techno1ogies.

Jan 1, 1986

By Waldemar Gooskov

IN his well-known work,1 published in 1867, P. Ritter von Rittinger gives the following formula for the velocity of a particle settling in still water: v=C/D(a -1) and for average grains he assigns to the constant C a value of 2.44. As is well known, the value of C depends on the shape of the grains resulting from crushing, and it is obvious that values obtained for coal particles will not only be very different from those for ore particles but will even be characteristic of coal from a certain seam. The only way of finding an accurate value of C, applicable to conditions in Russia, where all coal-washing plants are built on German principles, is to conduct a series of tests of which the results will determine what value of C is to be used. In the investigation outlined in this paper the theories of Prof. Robert H. Richards2 were taken as the basis of the tests; the slimes were removed from the charges to eliminate the trouble of handling them; and to obtain accurate results free from errors inevitably resulting from human observation, photographic apparatus was used and a series of pictures taken which form the basis for constructing a suitable diagram of velocity vs. time.3

Jan 1, 1928

By V. E. McKelvey

Some understanding of the United States mineral resource potential is essential for planning and policy making for the future. Reserves of some minerals are essentially lacking and for many others they are sufficient for only short term needs. Estimates of undiscovered resources of many minerals are substantial but are insufficient to support long term requirements, particularly if they continue to increase as they have in the past. Presently, subeconomic resources of some minerals such as aluminum are huge, but their recovery may require increased amounts of energy, which poses problems both as to cost and availability. Beyond these identifiable components of the United States mineral potential, what are the prospects? If they could be identified specifically, of course, they would be included in the above. An unappraised potential of new production and discovery can be expected to exist in known districts, where unproved methods of exploration may yield new discoveries; in new types of ore deposits; in metallogenic provinces as yet unrecognized or poorly explored; in frontier areas and in deeper parts of the crust as yet unexplored; and in presently subeconomic sources that may come within economic reach as the result of technologic advance. Other sources may extend the life of domestic material supplies -- substitution of abundant for scarce materials, recycling and prevention of waste, improved efficiency in recovery and use, and conservation of use.

Jan 1, 1976

By George Laird

IF IT IS true that Sir Walter Raleigh lost his head for his failure to find gold in the Guianas, the trumped up charge of "treason" might better have been "con-tributory negligence." That systematic investigation and development of the gold-bearing areas of both Dutch and French Guiana have not been accomplished is not due so much to the lack of gold as to the geo-graphical, physical and climatic conditions of the two colonies. The Dutch, as a people, are not prospectors. The French look upon "Cayenne," or French Guiana, as DJOEKA BOATS USED IN RIVER TRANSPORTATION. just what it is: a penal colony, which produces a certain amount of balata, gold and essential oils, all of which can be purchased from the natives with far less physical exertion than they can be secured from the "bush" or jungle. The colonies have had their gold "booms," and dur-ing these periods the production has increased to a considerable amount, but the hardships to be endured in reaching the fields, the cost of transporting tools and supplies, the ever-present fevers, the bite of the "57 varieties" of insects and, lastly but not leastly, the abundance of rum in the seaport towns, dampen the ardor of even the strongest; the production of gold is left to the "pork knocker" or illegal gold digger and to the comparatively few producing "mines."

Jan 10, 1922

By Lawrence Addicks

Discussion of the paper of LAWRENCE ADDICKS, presented at the San Francisco meeting, September, 1915, and printed in Bulletin No. 104, August, 1915, pp. 1471 to 1484. L. D. RICKETTS, New York, N. Y.--In the Southwest we have stored up millions of tons of tailings in which the copper exists partly as sulphide and partly in an oxidized condition. Mr. Addicks' first paper suggests a, likely process for the treatment of such material. His second paper 1 deals with the recovery of copper from clear solutions of notable strength, and such solutions may come from the sulphating roast or direct from the leaching of completely oxidized copper ores of which vast deposits are known to exist. What strikes me particularly about the latter paper is the keen perception shown and the clear manner in which the writer has attacked the fundamental principles of the process. He calls your attention to the fact that ferrous sulphate is necessary in the electrolyte and is an ideal depolarizer; that sulphurous acid must be, used to reduce the ferric sulphate produced and thus prevent re-solution of copper at the cathode; that mechanical agitation in the cell, in order to bring the ferrous sulphate in contact with the anode and the copper in contact with the cathode, is essential to efficient work; that lead anodes are

Jan 12, 1915

By Joseph W. Kupfner

It is a recognized fact that a good maintenance program is a pre-requisite for minimum delay costs and maximum availability of equipment. To develop such a program and to make it effective, one must establish detailed instructions pertaining to inspections, lubrication, servicing, and/or replacing of various parts. A schedule must also be established for these maintenance checks, whether they be weekly, monthly, or whatever period is essential for the equipment. The number of tasks to be performed becomes monumental, and the administration is beyond error-free human capacity. It is for this reason that the computer must be an essential element in any efficient and economical preventive maintenance program. The evolution of a computerized maintenance program began some 18 years ago in the Mining Division of USSteel. It started with a manual system of preparing cards containing preventive maintenance instructions that had to be performed on some regular basis. We were very quickly overtaken by the massive task of administration and distribution of instruction cards to the users. The task became insurmountable as more mines were added to the system, mines that were spread over a large geographic area. It also became evident that the ability to make changes in equipment assignments and in the "what to do" instructions would require more time than had been anticipated.

Jan 1, 1986

By H. R. Payne, A. F. Gorton, H. A. Schwartz

In a previous paper1 we published what we believed to be a correct stable equilibrium diagram for an iron-carbon alloy containing + 1.20 per cent. silicon. The purpose of the present paper is to record the results of studies concerning the effect of silicon on the location of the eutectoid points of both systems, including also certain incidental observations of general interest. We prepared white cast irons containing roughly 21/2 per cent. carbon, 0.05 per cent. manganese, and 0.03 per cent. each of phosphorus and sulfur, but of accurately known silicon contents which varied from 0.40 to 3.32 per cent. These were completely graphitized, and both A1 points determined, as in our previous work, the specimens being converted from the stable to the metastable condition and vice versa by appropriate heat treatments. Each stable alloy was heated to a few degrees above Arl for 3 to 7 hr., quenched and analyzed for total and graphitic carbon, the difference being the "combined" or, better, agraphitic2 carbon content of the saturated solid solution just above the eutectoid transformation. One specimen was lost through accident, and the 0.40-per cent. silicon material gave an anomalous result ascribed to difficulty in maintaining the stable system in the presence of but little silicon.

Jan 1, 1923

By Dean H. Ambrose

This paper presents an approach for representing and analyzing random motions and hazardous events in a simulated three-dimensional workplace, providing designers and analysts with a new technique for evaluating operator-machine interaction hazards in virtual environments. Technical data in this paper is based upon a project striving to reduce workers' risks from being hit by underground mining machinery in a confined space. The project's methodology includes human factors design considerations, ergonomic modeling and simulation tools, laboratory validation, and collaboration with a mining equipment manufacturer. Hazardous conditions can be analyzed in virtual environments using collision detection. By simulating an operator's random behavior and machine's appendage velocity, researchers can accurately identify hazards, and use that information to form safe design parameters for mining equipment. Analysts must be discerning with the model and not read more from the databases than what the simulation model was designed to deliver. Simulations provided an interesting approach to data gathering in that there was no need for live subjects and logistics - test sites and costs associated with experiments-became insignificant. Collisions versus speed, operators' size, and risk behaviors proved the versatility found in the data obtained from the model. Preliminary results show that response time significantly affects the number of collisions experienced by the virtual subject. Also simulation data suggests that more mishaps occur with hand-on-boom-arm risk behavior.

The mineral resource that a mining company has access to, represents the majority of the embedded value that exists within the company, as well as the competitive advantage that the company has over its peers. However, the real value is only realised once effective mining plans have been put in place, which optimise the extraction of the resource, and add measurable value to the company. The concept of mineral resource management (MRM) has been developed in South Africa, to ensure this optimisation happens in an integrated and quantifiable manner, such that value is added and risk is reduced, resulting in bottom line improvement for the stakeholders of the business. This paper describes the process of mineral resource management, and draws on successes and failures of various companies, to illustrate how it should be implemented, and what measures should be put in place to ensure its success. This requires a fundamental re-appraisal of the way in which mining companies plan and execute their businesses, and focuses attention on real value adding activities and behaviour through the use of economic value added as an appropriate metric by which to measure real value and risk. Specifically, the paper focuses on these aspects as applied to planning models and processes, exploration activity and risk management, to ensure operational and project success.

Jan 1, 2006

By Henry N. McCarl, John J. Dran

The academic community and the larger and more sophisticated mining companies have largely rejected the older mineral valuation methods such as the Hoskold and Morkill concepts and replaced them with "discounted cash flow" (DCF) techniques. The relevancy and usefulness of the older methods have been questioned primarily on the basis of their underlying assumptions that mining companies do not have numerous alternative investments and must use sinking funds deposited at market or "safe" rates of return to recover the purchase price of mineral reserves. The ability to reinvest in numerous (often nonmining) alternative business ventures, the changing purchasing power of the dollar, corporate income and other taxes, depreciation and depletion allowances, and modern financial management practice all militate against the continued use of the older valuation methods, especially for the larger mining companies. Small mining companies and individuals still use these methods largely out of habit and familiarity. The Hoskold Mineral Reserve Valuation Method The Hoskold method was developed prior to the evolution of modern accounting practices and before the days of the corporate income tax. At the time of its development, annual earnings of the firm were represented by the difference between cash revenues and cash expenses and were not subject to taxation by the government. Thus, earnings at that time were equivalent to what is today known as cash flow.

Jan 7, 1974

By Gil Espejo, Denise Duncan

"In Alberta, several initiatives are under way to form partnerships between educators and industry to work together in preparing a skilled and technically competent workforce for the future. One successful initiative is the Teachers in Business program which provides high school teachers one month paid internships in Alberta businesses. Initiated by the Science Alberta Foundation in 1992, this program has offered participating teachers a variety of work experiences and job shadowing tours in industry.A Growing Need of Education and Industry PartnershipsIn our ever evolving world, industry is in a tight race to keep up to date with new technology and to remain competitive. Industry is relying on the education system to provide them with the core base for their future workforce. To accomplish this, the education system needs the support of industry to develop the right focus to prepare its students for the race. What skills will our future workforce need? How can we best prepare our students for these needs?Teaching the latest in technology, especially at the high school level, is a major challenge. It is difficult for educators to keep abreast of the rapid changes in technology. High school graduates need exposure to the latest advancements. And so do their teachers. Students must be prepared to adapt to the challenges of the future, Le. global competition, rapid technological change and an expanding knowledge base."

Jan 1, 1995

By C. W. Eggert

"The idea for this talk came to me last year when I was attending the Canadian Gold Metallurgists Meeting. I talked about it to a friend of mine who is an authority on mineral dressing, particularly the theoretical end of the business. He remarked that this was an excellent technical note, why don't you write it up. This is what I have for presentation this morning. I hope in presenting this type of idea in this way it is in keeping with the tradition of the Canadian Gold Metallurgists which was to function on a not too sophisticated level and where operators could get together and trade ideas in an informal way.My basic thesis is that it should be possible to evaluate screen analyses by the application of the standard statistical probability theory. In any statistical analysis the sample is the first consideration. If we look at existing methods of size evaluation we find it is usually based on the fact that a given particle will pass one square aperature and not another. One system of standardizing how these aperatures will be set up is based on Rittenger' s work with the ratio of hole sizes proportional to the square root of 2. Keeping in mind the limitation we have accepted this as our method of 11 sizing"" in attempting to apply standard statistical methods to screen analysis."

Jan 1, 1968

By S. A. K. Forson, Newton A. Amegbey

In order to investigate production decline in Tarkwa Goldfields Ltd., located in a tropical rain forest, amongst other areas, a health survey was conducted with the aim to see 1. The health status of the workers. 2. Which parameters carry the most information about the health situation and which of them can be applied easily during screening programmes. 3. What steps could be taken to improve the situation. In all 249 workers were investigated. A non-invasive method involving taking of body weight and arterial blood pressure was used. All subjects were required to answer a questionaire. Emphasis was placed on the history of malaria and diarrhoea within the last six months. Both management and workers co-operated fully. Another set of 110 workers from a neighbouring tyre factory were also investigated for control. Among the underground workers, the percentage body weight loss during a shift increased with decreasing body weight. Dehydration levels could be as much as 4 to 5% of body weight. This could be attributed to the fact that workers took insufficient or no water during the shift. The health status of the mine workers was generally poor and in our opinion malnutrition combined with malaria severely threatens the health and well-being of the workers. Hypertension is also a problem. An improvement in production is intimately linked with the well-being of the workers.

Jan 1, 1989

By Nathaniel Herz

IN the operation of any ore processing plant, no matter what beneficiation process or combination of processes may be used, certain fundamental figures are regularly needed for essential records and accounting. These include amounts of ore treated and products made, with their assays, as well as quantities of labor and supplies used, with their cost. Usually labor and supplies are broken down and allocated to certain operations by the accounting department, and resulting tabulations are available for study by the milling plant management. However, to avoid too many minor details that would make these reports cumbersome and involved, much information that could be useful to the plant operator is often consolidated in such a manner as to have lost a considerable part of its value. To clarify this point, it may be stated that top management is most concerned with production figures and cost of production, while the plant operator is also interested in quantities of labor in man- hours and amounts of supplies used. Due to varying unit prices of labor and supplies, comparisons on a dollar basis alone are often misleading. With rising unit costs of the past few years now about twice as high as they were a few years ago, constant study of quantities involved is required to improve efficiency and productivity.

Jan 6, 1957