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By Gerald Verbeek

There are certain concepts that seem to invite responses from some, including some in the foundation industry and even some within DFI, that are at best surprising. Business owners and their employees share the desire that their company does well and continues to operate. Maybe company growth is not always realistic but maintaining the current level of activity is in the least what they hope for. In other words, they hope that their company is sustainable, and they are fully behind that notion. But when the concept of sustainability is raised, there is, at least with some, suddenly doubt that that is a good thing. And yet, that concept only aims to achieve at a grander scale what the owners and employees desire for their company. There are many definitions of the term sustainability, but probably the most commonly used description is that framed by the United Nations in 1987. It states that sustainability is the concept of meeting the needs of the present without compromising the ability of future generations to meet their own needs. Arguably that definition is too abstract and does not provide the type of specific goals and targets we are used to. To help with that, to some extent, in 2015 the United Nations formulated 17 Sustainable Development Goals (SDGs), to provide "a shared blueprint for peace and prosperity for people and the planet, now and into the future." And undoubtedly those SDGs are fodder for those that question the concept of sustainability in the foundation industry. How can our industry, they wonder, ensure that there is no poverty or hunger (SDG 1 and 2), and the climate action goal (SDG 13) immediately leads to the hot button topic of global warming. And maybe this is where advocates lose (some of) the sceptics of the sustainability concept, but hopefully they will continue to read this article that lays out why sustainability simply makes sense, also for the foundation industry and especially for DFI.

Nov 1, 2022

By John F. Blandy

Although the question of the "waste of anthracite coal mining " has been so frequently discussed, and a committee was appointed at the first meeting of this Society to consider and report upon the subject, still but little progress seems to have been made in arriving at a conclusion as to how it ran be reduced. That committee made a preliminary report at the August meeting, 1871, in which it divided the question into three parts, namely: Waste in mining, in preparing for market, and in transportation. I shall not here refer to the first item, as so much depends upon the peculiar features of each separate mine, and the skill of those in charge; but in reference to the second, that of preparing the coal for market in breaker and screens, I wish to make some remarks. There is no use considering the question, whether the coal should be broken up to suit the fancy of consumers; all miners are satisfied that it should not be, but the consumers decide that they want it that way, and the miner must submit, and simply utter his maledictions upon the head of the man who first suggested a breaker or screen, if that is any consolation to him. What is called waste in this process of preparation, is the dust and fine coal, which results from the breaking and screening, and, as we all know, this is a very important percentage of what passes from the slope to the top of the breaker. Now, if this dust and fine coal can be utilized—the slate which is picked out is not to be taken into consideration as waste—then we get rid of this item entirely. There is no question in my mind that this article can and will be used as a steam generator at least, and I think, therefore, that in depositing

I HAVE previously shown you in the Fifth Book the process of making guns and gun carriages, together with other preparations and methods of moving them. If I now failed to show you more about them, it would be as if I had pointed out only the useless shadow of a thing, for I did not show the kinds and arrangement of their supplies or how the effects for which they are made are achieved. For these reasons I now wish to tell you, in addition to what I have already said, how saltpeter is made and the methods of refining it well; what it is and how without it guns and many effects of violent and artificial fires would have been discovered in vain. After this, I also wish to tell you the methods of compounding the powders for large and small guns, and finally how these are loaded and discharged. I also wish to tell you how mines are made, and fire tubes, [149v] fire pots, squibs, fireballs, rockets, shells, grapeshot, and other similar devices for shooting fire in order to bum ships, supplies, bridges, and ramparts, or, in offense, for firing on batteries. I also wish to teach you to make certain bronze balls for shooting, which carry fire and break in many pieces when they hit. For surely, besides being terrifying to the sight, they would be harmful to armies lined up in battle when they are fighting. Likewise, I wish, to enlighten you as to how artificial fires are made that last long and are difficult to extinguish. Since these are fine and useful things in wars, every captain and soldier should give them consideration and know how to use them when necessary. You will be pleased to have this information if for no other reason than that you can teach it to those who take delight in celebrating holidays with festivities and with fires.

Jan 1, 1942

By R. G. Koelmans

In 2001 Platinum overtook gold in foreign revenue earnings for South Africa. The export sales from platinum group metals amounted to R29.3 billion as opposed to gold export sales of R28.6billion1. Organizations must undertake new ventures to replace old, worn-out and obsolete assets with new ones. These assets could be a building, a new product or process, a new mine, or anything that can help the organization to achieve its objective. These ventures are projects by their nature. When a project is pronounced a success, the judgement is usually based on some factual evidence, although not every one uses the same data. From the literature, it is obvious that there is a lack of consensus and objectivity as to what constitutes a successful project. The purpose of this paper is to address the following questions: ?What constitutes a successful project? ? How does one measure project success? ?How can one work toward project success? This paper addresses the requirements for project success of three of the primary stakeholders of a project, namely the business or client, the employees as far as the project team is concerned, and the local community. Indicators are developed into a work breakdown structure (WBS)-like chart to demonstrate success indicators. These indices take cognisance of all the constituents required for project success. The indicators are further developed to take cognisance of the requirements of the local communities. These indices are then weighted to arrive at a total score for the respective stakeholders. Using these WBS models, the success and performance of a project can be evaluated. This score is considered an objective measure of project success. Projects are evaluated more consistently across different projects and the project manager is provided with a management tool that can assist him/her in ensuring greater project success. The shortcoming of this approach is that the weights of the different indices have been estimated at this stage. Research will have to be conducted to more accurately reflect the weights assigned to the indices.

Jan 1, 2004

By J Bryant

In recent years the mining industry has suffered from skill shortages in a range of disciplines including mine geology. As a consequence, many businesses operate with incompletely filled organisation charts and technical professionals are frequently thrust into roles earlier than previous generations of geologists, engineers and metallurgists. Exacerbating the difficulties managers face with recruiting suitably experienced professionals is the churn of people through roles. Churn may be caused by internal pressures related to the rapid increase in projects and opportunities within a company or by external factors including the high workforce mobility resulting from the advent of fly-in, fly-out (FIFO). Historically, new entrants into the mine geology profession often received on-the-job training from their more experienced colleagues. This training, supplemented with targeted skills and knowledge enhancement through dedicated short courses, ensured the wide range of skills, knowledge and abilities required in the complex role of mine geology were continually renewed. Faced with an influx of new graduates and a dearth of mine geology professionals in the critical ten to 15 year experience range, the industry needs to develop new paradigms to ensure that the full business benefit of the mine geology function is delivered. This is increasingly important as the complexity of business planning built on geologically-based variables grows. Mine geologists are now faced with the potential incorporation of geometallurgy and waste characterisation along with energy efficiency, carbon-economy and other environmental issues into their roles. Providing baseline data, models, operational control and reconciliation for a wider range of variables further stretches the already limited geological resources available to the industry and exposes personnel with relatively low levels of experience to potentially business transforming decision processes. This paper outlines a successful approach to mentoring at the individual and team level. It discusses what went well and what could have been done differently from both the mentor and menteeÆs perspective with examples from case studies and offers insights into a new approach to dealing with gaps in organisation charts and high turnover of personnel.

Jan 1, 2009

By John F. Blandy

ALTHOUGH the question of the "waste of anthracite coal mining" has been so frequently discussed, and a committee was appointed at the first meeting of this Society to consider and report upon the subject, still but little progress seems to have been made in arriving at a conclusion as to how it can be reduced. That committee made a preliminary report at the August meeting, 1871, in which it divided the question into three parts, namely Waste in mining, in preparing for market, and in transportation. I shall not here refer to the first item, as so much depends upon the peculiar features of each separate mine, and the skill of those in charge; but in reference to the second, that of preparing the coal for market in breaker and screens, I wish to make some remarks. There is no use considering the question, whether the coal should be broken up to suit the fancy of consumers; all miners are satisfied that it should not be, but the consumers decide that they want it that way, and the miner must submit, and simply utter his maledictions upon the head of the man who first suggested a breaker or screen, if that is any consolation to him. What is called waste in this process of preparation, is the dust and fine coal, which results from the breaking and screening, and, as we all know, this is a very important percentage of what passes from the slope to the top of the breaker. Now, if this dust and fine coal can be utilized-the slate which is' picked out is not to be taken into consideration as waste-then we get rid of this item entirely. There is no question in my mind that this article can and will be used as a steam generator at least, and I think, therefore, that in depositing

Jan 1, 1877

By R J. Everett

The mining industry is beginning to adopt quality systems based on the requirements of International Standards for quality assurance, such as the ISO 9000 series. Indications from similar industries are that considerable benefits are to be had from their adoption. This paper describes the use of the International Standard ISO 9001 for quality assurance within BUKA Minerals Limited. This provided guidance for the development of a clear statement providing agreement on the processes to be followed and the outputs required when dealing with outside service providers. Discussion focuses on the interaction with BUKAÆs consultants and contractors during the specification stage, resulting from the application of quality assurance techniques. Risk analysis was used to identify and manage the risks associated with the companyÆs contract for geotechnical and mine design services and the tender for a mine development program of work during the feasibility stage of the project. Setting acceptance controls for the deliverables from such contracts is traditionally fraught with difficulty. BUKA used Failure Mode and Effect Analysis for exposing underlying risks that were not effectively being countered. The briefs were reviewed and additional controls were developed to manage the risk. These controls have provided clearer instructions to the consultants and contractors, indicated audit points for the company and defined the deliverables. There exists within the company, and among its outside service providers, a clearer understanding of what is to be achieved and how it will be measured. The process has imparted considerable confidence to both parties on how the work will proceed and what outputs are to be provided. Some discussion is provided on how quality principles are being applied throughout industry and commerce, generally, and how they may apply to the mining industry. The paper argues that, far from being an appendix to the tendering process, Risk Management should be a mandatory step integrated into the definitions of the work.

Jan 1, 1998

By William Kent

More than twelve years were spent by Wöhler at the instance of the Prussian Government in experimenting upon the resistance of iron and steel to repeated stresses. The results of his experiments are expressed in what is known as Wöhler's law, which is given in the following words in Du Bois's translation of Weyrauch:* " Rupture may be caused not only by a steady load which exceeds the carrying strength, but also by repeated applications of stresses, none of which are equal to the carrying strength. The differences of these stresses are measures of the disturbance of continuity, in so far as by their increase the minimum stress which is still necessary for rupture diminishes." A practical illustration of the meaning of the first portion of this law may be given thus: If 50,000 pounds once applied will just break a bar of iron or steel, a stress very much less than 50,000 pounds will break it if sufficiently often repeated. This is fully confirmed by the experiments of Fairbairn and Spangenberg, as well as by those of Wöhler; and, as is remarked by Weyrauch, it may be considered as a long-known result of common experience. It partially accounts for what Mr. Holley has called the " intrinsically ridiculous factor of safety of six." Another "long-known result of experience"—although this has not, as the writer believes, been investigated by scientific experimenters—is the fact that rupture may be caused by a succession of shocks or impacts, none of which alone would be sufficient to cause it. Wrought iron will crystallize by repeated blows in service and become weaker than cast iron. Iron axles, the piston-rods of steamhammers, and other pieces of metal subject to continuously repeated shocks invariably break after a certain length of service. They have a "life" which is limited. Iron rods in bridges sometimes crystallize and break, although the rods in most of our iron bridges

Jan 1, 1880

By C. K. Leith

(San Francisco Meeting, September, 1915) IN 1911, we published in the Transactions a brief account of the lateritic alterations of serpentine in eastern Cuba, producing the important iron-ore deposits of the Mayari and Moa districts.1 The special feature of that article was a quantitative treatment of the alterations, based on analyses, to show just what had happened in terms of chemical, mineralogical, and physical changes. Professor Kemp has published an interesting account of these ores, containing additional quantitative observations of his own, tending essentially to confirm the nature of the changes that bad been worked out.2 His discussion suggests to us the desirability of publishing certain additional quantitative data which were not included in our previous article. This seems especially desirable because quantitative measurements of lateritic alterations are rare, and this particular case may be regarded as typical of a fairly wide range of alterations of this kind. At the time of our examination of Mayari and Moa, deposits 29 complete analyses were supplied us by the chemists of the Spanish-American Iron Co., representing a graded series from the unaltered serpentine rock below to the ore at the surface. These analyses are given in the accompanying table. The mineralogical composition of the ores and rocks is comparatively simple and can be easily calculated from the analyses. In Fig. 1 the mineralogical changes from the serpentine rock below to the lateritic iron ore above, based on the analyses, are expressed in terms of weight, assuming alumina to have remained constant during the alteration. It is not easy by mere inspection of this table of analyses to determine what the progressive chemical changes have been in development of the ore. In order to bring this out clearly, the analyses have been graphically represented in Fig. 2 in such a fashion as to show the progressive additions and losses of substances during alteration.

Jan 7, 1915

By Leonard Waldo

PROBABLY some of the views advanced in this paper will appear, from a metallurgical standpoint, little less than revolutionary. It is with considerable hesitancy that I venture to offer a few thoughts concerning what, seems to me to be perhaps the most important development of metallurgy since the introduction of Bessemer steel. Dr. John Percy, with that rare insight which characterizes the epoch-making man, described in a communication to the Royal Society, about 1855, an alloy of duminum and copper which he called aluminum-bronze. The name has "stuck." The term "bronze" has been so variously used that I confess I do not know exactly what constitutes a bronze; but I know that in the great materials of engineering simplicity of composition is a cardinal excellence; and I wish to venture the suggestion that aluminum-bronze is not an alloy of aluminum and copper in any such sense as the compounds of tin and zinc with copper (except the copper-tin compound SnCn3) are alloys. There are several reasons which lead me to this view. In the first place, if a series of bars be prepared containing varying percentages of aluminum and copper, and the electrical conductivity of these bars be carefully determined, a curve of conductivity will be obtained, as shown in Fig. 1, which represents the result of such experiments. While I am not sure, at this time, that the values of conductivity shown in this diagram are wholly dependent upon the percentage of aluminum added, the assumption is a probable one; and the curve indicates that an extremely small percentage of aluminum affects the conductivity in a ratio out of all proportion to the amount of that metal. Another reason is drawn directly from experience in the foundry. If we take from the furnace a crucible containing melted aluminum and one containing melted copper, both at a little more than a red heat, and pour them together, the reaction is so intense that the

Jan 1, 1895

By H. Ries

IN THE marketing of mineral products, it is always highly desirable for both the producer and the consumer to be able to discuss things in a common language, and this can only be done if there are standard methods for expressing the properties of the raw materials. Having developed such a form of expression, the next step would be the making of specifications, which may serve as a basis for selecting raw materials. Considering the large number of non-metallic minerals that are used, there are not a few for which there are no standard laboratory tests to be used in determining their properties, or even standard specifications on which grades or market price may be based. Indeed in many cases the consumer simply requests the producer to submit samples, and rejects or accepts them without any explanation. Could the producer know in advance just what the consumer needed, time and money might often be saved. It appears to the writer that it is of the highest importance to devise standard laboratory tests wherever possible, as this enables the consumer to state definitely what he needs, and is of great assistance to the producer. It should also work to reduce misunderstandings and disputes. 'In the case of sands, we find that they show a wide variation in their character, ranging from those that are so coarse as to be of gravelly nature to those that are so fine that they might be classed as silt; and from very clayey ones to those that are practically free from clay. For this wide range of sands, we have a corresponding variety of uses, which are based mainly on the physical properties of the sand, although these are not always very definitely stated. The chemical composition need rarely be considered, if the sand is of siliceous nature. To determine and express these properties there should be standard tests, which are to be followed in all cases where the material is tested in the laboratory.

Jan 1, 1926

The mining industry has indeed gone global. International minerals producers are spending big money to move into countries that were off limits a few years ago. Due mostly to political reasons, these countries' huge mineral deposits - worth billions of dollars - were locked up and mining companies could only sit on the side and wonder "what if." Now much of the world is going the free market route. Once closed countries and developing nations are rewriting their mining and tax laws hoping to attract foreign investment to develop their natural resources. And big businesses - mining companies included - are lining up to get their share. But with new opportunities come new risks. While emerging nations are slowly accepting the free market concept and the privatization that goes along with it, many remain plagued with political instability and violence. Even developed nations carry their unique risks. Some of these include inadequate or contradictory legal and regulatory infrastructures, political patronage and outright corruption. So companies hoping to expand into new regions of the world must do more than examine the market. They must study the political stability and structure of a country, as well as its tax and environmental laws. And they must guarantee the safety of their employees. Control Risks Group is an international management consulting company that assists companies preparing to move into a new country. It employs about 225 people in 14 offices throughout the world. Control Risks personnel include lawyers, bankers and former law enforcement officers and intelligence people. The company held a one-day seminar in Washington, DC to update some of its clients on the state of affairs in various regions of the world. The seminar also covered extortion, corruption and product diversion. About 175 people attended the seminar. Speakers included Control Risks' operators, analysts and investigators. Here is a summary of what some of those people had to say.

Jan 1, 1998

By O. L. Kowalke

THE measurement and control of temperatures have assumed positions of great importance in many industries. The manufacturers of byproduct coke and carbureted water gas find that proper temperature control helps to produce a better product and economizes in the use of raw materials. In the manufacture of glass, enameled ware, brass, and high-temperature refractories, temperature control is now regarded as being coordinate in importance with the control of materials used. To control such processes as malleablizing cast iron, and hardening, tempering, and annealing of steel in a manner to meet exacting market requirements has, within recent years, involved the installation of large and expensive pyrometer equipments. In many of these installations, it was necessary not merely to measure but also to record the temperatures over a period of time and thus obtain a record of the entire heat treatment and an effective check on the workmen in charge. In view of the importance of temperature measurement and control in such a wide variety of industries and the necessity for proper supervision of the installation and operation of the outfits, the following questions may be pertinent: What instruction is offered by the engineering colleges and what departments in the colleges are responsible therefor? The latest available catalogs of ten prominent engineering colleges east of the Mississippi River showed courses in high-temperature measurements given by the departments of physics. These courses, in general, were described as comprising classroom and laboratory instruction in the theory of high-temperature measurements, together with exercises in the calibration of the various devices used. In some cases it was stated that consideration would be given, in the courses, to the practical applications in the industries. In only one. college was the course required of all engineering students; in most colleges it was optional; in a few colleges, it was required only of certain groups. In colleges offering a course in metallurgical engineering, instruction in pyrometry was always given in connection with metallurgical laboratory work. The students in ceramic,

Jan 8, 1919

D. J. DEMOREST,* Washington, D. C. (written discussion ?).-This paper is a real contribution to technical science; it will make it' easier to think accurately about the inner workings of a blast furnace. I was rather surprised to read that the authors regarded as a new discovery the idea that a molten mixture of CaO, A1203, and Si02 is a molten solution of the compounds of these oxides rather than of the oxides in each other. Surely no. chemist with an active respect for the known facts of chemical affinity could believe that these oxides could be melted together without forming compounds, and that these compounds would then dissolve in one another. This work does, however, help to establish what it was supposed must be true. I think it is worth while, in the light of the work of the Geophysics Laboratory, this work of the Bureau of Mines, and that of previous investigators, to visualize what happens as a charge passes down through a blast furnace, thinking especially of the slag-forming materials. These are chiefly kaolin (Al203.2SiO2.2H2O), quartz, and limestone. These substances do not undergo much change until the limestone decomposes at about the middle of the furnace, whereupon the chemical affinities of CaO and SiO2 must begin to he active; especially if there is any amorphous Si02 present. This forms CaSiO3, and the SiO2, CaSi02 and Al2-032SiO2 then come together to form the binary and ternary eutectics so well located by the work of the Geophysics Laboratory. No matter how much lime has been charged into the furnace, the formation of this eutectic will start it about the same height in the furnace and the gangue will start to get pasty at the same height. If the charge is such that the

Jan 4, 1918

By Henry Howe

THE data which are collected in Table 1 show that the ferrite of low-carbon steel and of electrolytic iron, like the network of hypo- and hyper-eutectoid carbon steel, inherits, either absolutely or relatively, the, grain size of the mother austenite from which it is born in cooling through the transformation range. This evidence is so abundant and concordant as to cast doubt on Prof. Jeffries' 1 hypothesis of what might be called reversed inheritance, by which he explains Mr. Ruder's observation2 that the grains of a "slug of pressed pure electrolytic iron powder"were coarser, perhaps 12,000,000µ2, after a 3-hr. exposure to 1000° C. than after a 3-hr. exposure to 1250-1300°, when they were about 35,000µs. His explanation implies a natural tendency of coarser austenite grains to yield finer ferrite ones than spring from finer austenite grains, so that the inheritance is reversed. What seems to me a simpler explanation is that the enormous grains which followed the 1000° heating were not inherited from the mother austenite, but were formed by the process of natal coarsening, by means of which Stead and Carpenter developed grains of this same order of magnitude in this same kind of material, on heating to 950° or to 1000°, the temperature used by Mr. Ruder, provided the exposure was not unduly prolonged, and it does not seem to have been in Mr. Ruder's case. That their coarsening was natal and not through inheritance is shown first by the fact that their grain coarseness was out of all proportion to their relatively low temperatures and short periods, and hence was very far in excess of the grain size which the mother austenite must have had, and second and more cogently by the fact that the shape of these coarsened grains was evidently determined by the temperature distribution which existed during and immediately after the Ar3 transformation, that during the passage from the gamma to the non-gamma state.

Jan 9, 1917

By Lewis M. Haupt

IT has given me great pleasure to read, in the papers recently published by this Society, the discussions on the subject of Technical Education, which were developed at the joint meeting held at the Franklin Institute in June, 1876; and since it was impossible for me to be present, I desire to improve this my first opportunity of adding the weight of my testimony and experience to what has been so ably presented by others. It is a subject about which the people need to be kept agitated, that their views may expand with the demands made for a higher and more thorough education. It is the public at large, the capitalist, the manufacturer, and the laborer, who are to be benefited more or less by this elevation of the standard of our professional schools, and it is but just, therefore, that the schools should look to them for the means with which to accomplish so desirable an object. It is no doubt to the interest of a metallurgist to employ a skilled laborer who will prevent waste by properly proportioning his materials ; by regulating the supplies of air and fuel ; by arranging his plant in the most economical manner, and by disposing of his products to the greatest advantage. The engineer is benefited by selecting for an assistant a person able to determine the values of his factors of safety for the same materials in different forms and positions, avoiding expensive suits for damages and cost of reconstruction; he should be able to so locate a road as best to fulfil the requirements of a through traffic, and yet develop local industries. But I need not multiply instances to show what all will readily concede, viz.: the advantages of a theoretical education ; that was fully demonstrated at the previous special meeting, but it is still an open question whether the practical instruction should precede, accompany, or follow the theory.

Jan 1, 1877

By C. B. Huntress

"We have ourselves to blame in the steel industry for our condition." These words were addressed twelve days ago by James A. Farrell, President of the United States Steel Corporation, to his "comrades" at a meeting of the American Iron and Steel Institute. They carry a note of challenge to all industry, and particularly to the coal industry, where they point the way to the pressing need for operators everywhere to get their feet under one table. It is that note which I would stress to all producers. You have yourselves to blame for your condition. True, there are inter-district competition and competition of substitute fuels, but they'll always be with us, more or less, and the only sensible, sane course is to remove the evils within our respective districts, which can be done only by constructive effort along cooperative lines. It's the same story in Alabama, the same in Illinois and elsewhere. The larger number of the men gathered here are at the front, as it were, in the business of mining coal. They are the men who are doing a remarkable operating job. And naturally, the sessions of this annual meeting treat of news from the front, of technical problems. But, as in actual warfare, those at the front are often uninformed of developments in the rear. They keep on fighting without fully sensing the significance of a disaster at headquarters. You've played your eighteen holes today and evidenced the efficiency of your technique in the, production of coal. It is not amiss to take advantage of this moment, the nineteenth hole, to ponder over what it's all about. After all, what do improvements in the art of mining mean if business policies engulf you in red ink? To the extent that mechanization is a factor in increased overhead, which in turn increases the pressure to produce regardless of market demand, it only aggravates our troubles unless there is the controlling influence of coordinated effort.

Jan 1, 1931

THE Bergbüchlein and Probierbüchlein occupy a unique position in the literature of mining and metallurgy, for, they are the first printed books on any aspect of the two related professions. The first printed book on any subject has an allure that may not be entirely warranted by the strict historical significance of its contents. Among the books of the first century of printing there are very few that contain information that was new at the time of publication. Much' of what they recorded had been previously circulated in manuscript form. Printed books are nevertheless of great value because they mark the time when the author's words, free from errors-or at least with the same errors-became available to large numbers, of readers, who thus could easily and cheaply acquire a common background for their future work. Moreover, though there is occasionally some doubt as to the exact year of publication'(as in the case of the present works), it is generally easier to date a printed work than a manuscript, and thus to provide a fixed coördinate in history. The Bergbüchlein, "The Little Book on Ores," is the first printed work in the field of mining. It is an introduction to mining geology, which means that it was not addressed to the practicing expert but was intended to rouse the interest of beginners in the various aspects of a future vocation. It touches on the theories of the generation of ores, introduces and defines some of the most frequently encountered technical terms of the profession, and indicates what knowledge and tools are required for successful prospecting and mining. It also describes the ores of the seven most important metals. For those parts that deal with theory the author accepted uncritically the traditional teachings of the alchemists and the astrologers; his hints on where to find promising ores are based partly on superstition; but, there is enough factual,

Jan 1, 1949

By C J. Larder, S E. Turner

The concept of underground grinding is not new, but to a metallurgist and a mining engineer this could be considered unconventional. The idea of pumping a ground slurry several hundred metres from underground in a single lift could also be considered to present a daunting engineering challenge. Using a practical example of a mine in Australia where the owners have requested not to be identified, this paper challenges the conventional thoughts on these concepts and shows that with basic sound engineering practices the production of a ground slurry from underground could potentially provide significant operating cost savings. The supply of ore from the underground mine is currently drawn from depths approaching 800 m below the surface. The cost of hauling the ore to the existing underground crushing station located 500 m below surface has been steadily increasing. A number of alternatives to reduce the mining and processing unit operating costs were examined by Sinclair Knight Merz (SKM) and the mining company. The most radical of these is the use of hydraulic hoisting of ore at an increased production rate. Numerous questions were asked, such as: How does one get a SAG mill or an HPGR crusher underground? Where does one locate a grinding mill underground? Does the technology exist to pump the slurry to surface in a single lift? What will be the cost benefits? What are the risks involved? The study covered the two main technical issues underlying the potential benefits. Firstly, technical evaluations were undertaken on the pumping technology currently available for single and multiple lifts to surface. Secondly, the issues relating to the feasibility of delivering and locating a SAG mill underground were reviewed. Although the capital costs for this project are significant, the operating cost savings showed a potential payback period of less than two years, and furthermore provide the basis for an increased mine life, especially at lower metal prices.

Jan 1, 2005

By D. H. Bacon

Nearly all men are too busy with their own affairs to keep informed of the progress in other lines. From time to time we read statistics showing the development in some industry that astonish us; but the feeling of surprise soon fades: to be followed by others that likewise pass away. A short resume of what has been done in one line may be of interest. Down to late in the fifties the ore-product of Lake Superior mas handled over a mule-tram-road to Marquette; now the Duluth, South Shore and Atlantic, the Chicago and Northwestern, the Wisconsin Central, the Duluth, Superior and Western, the Duluth, Mesabi and Northern, the Duluth and Iron Range and the Lake Superior and Ishpeming railroads serve the shippers. Down to nearly 1870 a 700-ton ship was an enormous craft, the loading of which required two days; the unloading being seldom accomplished in that time. In 1871 the largest ore-barge carried 1050 toils and made twelve trips per season. Now the cargoes reach 5000 tons, the loading requiring less than three hours, and the unloading ten hours. Now the mines cover more land than was familiar to even the " timber-cruiser " when the Jackson mine was opened. The annual shipments have grown from a few thousand to 10,000,000 tons, and the ability of the mines to produce is not taxed. Lake-freights are at one-eighth, and rail-freights at one-quarter, of early prices. The deeper waterways, commodious locks and large ships of to-day are in a greater measure due to the movement of ore than to any other cause. Great savings have been made in each detail of each department. The only item of cost that has not been lessened, I am glad to say, is the money paid to men. Wages, measured by what they will buy, are as high

Jan 1, 1898