Search Documents

By K. J. Griffin, G. W. Rosval

"In our increasingly competitive market, attempts to improve productivity by increasing axle loads have placed more severe demands on rails. CP Rail thus requires stronger, tougher, and more wear-resistant rails from steel manufacturers. The choice of any rail steel is always a compromise between technical and economic factors. The technical assessment of a candidate rail consists of laboratory and field testing. Laboratory evaluation of rail steels cannot adequately model many service conditions and must, therefore, be supplemented by long-term field testing. The field testing conducted on CP Rail is the subject of this paper.Long-term, in-track, assessment of candidate rail steels begins with the selection and re-laying of a test curve representative of the intended service with both the candidate rail and a control rail steel (i.e. the present intermediate or premium rail standard). The wear performance of the candidate rail is evaluated, in relation to that of the control rail, using data obtained with a rail profilometer developed by the Research and Development Department of CP Rail. Qualitative observations are also periodically made to evaluate the relative susceptibilities of the two rail types to surface defect formation. Testing continues until stable metal loss patterns are achieved. Relative life predictions are then made and detailed monitoring of the test site is discontinued.CP Rail's in-track assessment program for premium rails has resulted in the establishment of a new CP Rail premium rail standard - low-alloy, head-hardened, rails have replaced high alloy rails. The wear/fatigue lives of these new premium rails exceed those of our previous standard by more than 50%, and they also exhibit excellent weldability. CP Rail will continue to evaluate new premium and intermediate strength rail products."

Jan 1, 1988

In presenting this address I am conscious of the honour that has been paid me in my election to this important office, and I am very aware that I follow, in the position of President, many distinguished men who have led the Institute over the 70 years since its inauguration in Broken Hill in 1893.It is perhaps appropriate tonight that I intend to talk about a metal which recalls the birth-place of the Institute, and is also one with which I have had a direct association throughout the whole of my working career. This metal is Silver.Silver is associated traditionally in everyone's mind with money and silverware, and has always been prized for its natural beauty and elegance. It is today one of the few metals in which world consumption has outstripped production, and the events which have occurred to bring about this situation make an interesting story.In telling this story, I propose firstly to indicate our development as a silver producing country, give an historical review of the metal, trace its use as currency and the factors influencing its price, and then say something of the old and new uses of silver. Finally I shall give some comments on silver production in Australia today.Australia, with 6-5 per cent of the world's output of silver, ranks sixth among the producer countries and over the years has contributed 892.5 million ounces to the world's supply which, based upon production since the discovery ofAmerica, is estimated to have been 22,150 million ounces or nearly 680,000 tons.Although our production appears relatively small by...

Jan 1, 1963

Gullies are the vital in-stope excavations that provide access for mining personnel and material to, and mined ore from, the producing faces in the tabular hard rock mines. They pose a serious problem in most mines because they induce stress orientations, which, combined with blast damage, produce adverse rock fracture patterns that contribute to the loss of hangingwall and sidewall integrity. Rock-related injury statistics confirm this by highlighting gullies as the second-highest risk area in South African hard rock mines. Inappropriate gully geometries, poor blasting practice, and non-adherence to accepted standards worsen the problem. The aim of this work is, firstly, to provide guidelines to select the correct gully geometry and appropriate support for a particular geotechnical environment and, secondly, to review the practical issues behind gully safety and stability. In order to meet these aims, this paper reviews the available literature on gullies and their history, and reports on an industry-wide survey of practices and opinions. Then it covers observations from underground visits to 107 gullies situated in the respective geotechnical environments of the Basal Reef, Beatrix Reef, Vaal Reef, Carbon Leader Reef, Ventersdorp Contact Reef, Kimberley Reef, Kalkoenkrans Reef, Merensky Reef, and UG2 Reef. Despite the differing geotechnical conditions and gully geometries, common problems are experienced with geological structure, stress, and fracturing. Results from numerical modelling are also presented to help analyse the underground observations and to quantify the merits of the different gully layouts. It is concluded that there are no new techniques available to improve gully stability, but that significant improvements in safety are attainable by employing the correct gully geometry for the geotechnical environment, good blasting practice, and appropriate support.

Jan 1, 2002

By Alexander N. Winchell

"THE MICHIGAN COPPER DISTRICT.Location. The copper mines of Michigan are all in the north¬ern part of that state on the Keweenaw Peninsula, which extends from the (Michigan) mainland for about seventy miles northeast¬erly toward the middle of Lake Superior. The mines occur in a belt or zone occupying the central portion of the peninsula from end to end.. The most productive mines for many years past have been those located not far from the city of Houghton in' the central part of the zone, in a section extending about ten miles southwest of Houghton and fifteen miles northeast. The most important mines in order of.location, from the northeast to south¬west, are the following: Mohawk, Ahmeek, Allouez, North Kearsarge, Wolverine, South Kearsarge, Centennial, Calumet. and Hecla, Osceola, Franklin, Quincy, Hancock, Isle Royale, Superior, Baltic, Trimountain, and Champion. The first three named are in Keweenaw county and all of the others are in Houghton county. Still farther to the southwest are the Lake, Mass, Adventure, Michigan, Victoria, and White Pine mines. These are in Ontonagon county.History. The exploitation of these copper mines extends back into prehistoric times. There is little evidence that the American Indians carried on mining operations in this region in the period shortly before the advent of white men, but there is abundant evidence that the ancestors of the Indians, •or some earlier inhabitants of the region, carried on primitive mining operations. For example, Mr. S. O. Knapp, Agent of the Minne¬sota Mining Company, in the winter of 1847-48, made the first discovery of prehistoric mining. This event is described as fol ,lows by Foster and Whitney : Location: As shown on the accompanying map, the Mar-quette district extends from the region of Marquette on Lake Superior westward for about forty miles. The main basin of the district is only about three to six miles wide, but outlying areas which are commonly regarded as belonging to the same mining unit, make the north and south dimension of the district about twenty miles. The most productive portion of the area is in the vicinity of Negaunee and Ishpeming, .about ten miles from Mar¬quette, but important mines are found also all along the range as far west as Michigamme and also to the south in the fold known as the Republic Trough. Comparatively recent developments indicate that important ore bodies have been developed in the outlying Swanzy district about eighteen Miles nearly due south of Marquette.The Marquette Iron District.History: The first discovery of iron ore in the Lake Supe¬rior region was probably that made in 1844 near the site of Ne-gaunee by the government surveying party in charge of William A. Burt, sent out under the direction of Douglass Houghton. This surveying party was using a solar compass, invented by Mr. Burt, and noticed variations in the direction of the magnetic needle at various times and places, but. on the 19th of September, while running the east line of Township 47 North, Range 27 West, the needle varied from its normal position until it stood nearly at right angles thereto."

Jan 1, 1920

By Claude Cunningham

Ths oonoept of precise. eooursts timing with Elsotronic Delay Detonators (EDD’s) was first ssriously sddresssd in ths mid 80’s end much wss made of the cheapness end profusion of digital wstohes in terms of the likelihood of EDD’s also being cheap and essyto produce. Ten years Iater. with every major explosives group end many elsotronios groups having instituted projects to capitalize on the promise of these devices, production devices are still to come into asneral use.

Jan 1, 1994

By Thomas H. Wilson

Common offset and refraction seismic data have been collected over four longwall panels at two different locations within West Virginia. Surveys prior, during and after mining were made in both areas. The velocity of seismic wave propagation in the overburden rocks is observed to decrease in response to panel emplacement. Variations in the magnitude of this reduction, apparent as an additional first arrival time delay in the after mining common offset surveys, do not appear to correlate directly to the amount of subsidence that has occurred. Velocity reduction and signal absorption zones are also produced in the cover beyond the panel face over the adjacent unmined areas. Signal absorption and velocity reduction zones have also been observed over room and pillar entry areas between mined panels. Velocity reduction zones have been- observed beyond the panel face in both shallow and deep mines, but the signal absorption zone has not been observed over the deeper mine. Changes in the compressional wave velocities of the cover rocks are associated with changes in their elastic moduli. Differences between borehole derived and surface seismic derived interval velocities, are related to differences in the properties of the bulk volume sampled by each method.

Jan 1, 1988

"What can we do in ground engineering to reduce damage to the environment, to repair historic pollution, to reduce our demand on basic resources and to reduce the carbon footprint of our industry? Some developments in geotechnical engineering are already heading in the right direction. These include reductions of ground pollution from grouting, improved dewatering procedures and advances in mix-in-place processes, ground improvement and jet grouting.There is increased interest in certain promising technologies (for example, drilled partial or full displacement piles), but this approach remains for the moment somewhat avant-garde. These piles require substantially greater power to install, and the overall sustainability balance for general application has yet to be shown to be in their favour. They are particularly suited to polluted sites where the problem of dealing with spoil would be costly and where, in the past, driven cast in-situ piles would have been employed. Drilled displacement piles offer some environmental benefit over driven piles in that they cause far less drawdown of potentially contaminated near-surface ground into sensitive, underlying aquifers.There is also great interest in various means of increasing the frictional capacity of bored piles, both conventional auger and continuous flight auger (CFA) piles, by threading or ribbing the soil/pile interface. The increase in adhesion capacity allows reduction in the pile dimensions necessary for a specific load. This obviously leads to less construction waste, but also to less permanent material consumption in the piles and also in the pile caps.The role of ground improvement remains significant for brown land sites and lower capacity foundations. Information technology (IT) has improved the quality assurance of stone column construction, for example. From the sustainability point of view, this is a good news method; here is no cement, no pollution and little obstruction to future redevelopment. We now need to introduce recycled crushed materials instead of natural aggregate as general practice and the technique’s green credentials will be really compelling."

Jan 1, 2009

By Michael MacMillan

The mining industry has always operated under intense public scrutiny. Community expectations, investor pressures, regulatory obligations, and environmental oversight create a uniquely complex communications environment. In recent years, technological change, climate urgency, and geopolitics have reshaped how the industry communicates its role and value. The rise of artificial intelligence in the information ecosystem represents yet another fundamental shift. As AI evolves, an organization’s reputation will no longer be shaped solely through human interactions, media coverage, social activity, or corporate disclosure. Increasingly, public understanding depends on how AI systems interpret and represent company information. These systems influence search results, conversational tools, news aggregation, social discourse, and even investor intelligence platforms. As AI-generated summaries, answers, and narratives become the default interface for stakeholders, they also become authoritative in shaping trust. For mining companies, this creates both risk and opportunity. The organizations that recognize how AI reads, prioritizes, and amplifies information will be better positioned to build trust. Those that remain silent or rely on traditional communication methods may find their reputations being algorithmically defined without their participation. This paper explores how mining companies can proactively engineer their reputations in the age of AI.

Jan 1, 2026

By Jr. Holmes

The Bureau of Mines drilled and sampled the more important magnesite deposits in the Currant Creek Mining District, White Pine County, Nev. The properties of the Ala-Mar Magnesium Co., Inc., and the Nevada Magnesite Co. were examined in August 1942 by D. W. Butner, engineer of the Bureau of Mines, to determine the advisability of investigating the deposits under the strategic minerals program. Development involving diamond drilling, trenching, and sampling was started September 1, 1942, and was completed in the latter part of November 1942. The deposits are on unsurveyed public land in T. 12N., B. 59 E., M.D.B.&M., in an area of high relief ranging from 7,300 to 8,100 feet in altitude. Both properties are situated northwest of the Tonopah-Ely Highway, U.S. Highway 6, from which a dirt road extends about 4.6 miles northwesterly, about 35 miles southwest of Ely, to the Ala-Mar property, and another dirt road extends about 10 miles westerly, about 26 miles southwest of Ely, to the Nevada Magnesite property. The magnesite occurs as irregular nodules, veins, and lenses in a bedded calcareous tuff formation, which overlies a group of volcanic rocks, and which is capped by remnants of rhyolite flows.

Jan 1, 1950

By Charles Enzian, Donald F. MacDonald

It is a far cry from the small and uncertain mining efforts of 50 years ago to the splendidly equipped and solidly financed organiza- tions that now handle thousands of tons of ore per day. The old mining was largely speculative; the new is practically on a manu- facturing basis. In the old days of mining the aim was, chiefly, to find comparatively rich ore; modern practice looks more toward efficiency in mining and milling, so that vast tonnages of low-grade material may be worked at a profit. The old operators had faith and hoped for good returns; the new ascertain with a fair degree of precision what the available tonnage is, what the cost of mining and treating the ore will be, the time necessary to exhaust the deposit, the capital required, and the net profits to be made. The old mining was financed on a highly speculative basis, and the value of mining stock was largely controlled by the imaginations of the promoters and of the individual holders. In the new régime the financing of mines is often as conservative as the financing of manufactures or railroads, and the value of stock, quoted on the leading exchanges, is controlled by the carefully estimated profits in sight. Of course, with every legitimate industrial enterprise go certain business risks, and mining is not exempted from these. Then, too, valueless mining as well as valueless industrial stocks are sometimes offered for sale by the intentionally dishonest, or the ignorant. However, the prospective purchaser of a mine nowadays, if he is willing to pay for the services of reputable mining engineers, can obtain information on which to base an opinion as to the quality of his investment. The relatively recent development of cheap and efficient methods of mining and of ore dressing has given value to low-grade ore bodies that a few years ago were almost valueless. The iron mines of northern Minnesota have been fruitful in developing efficiency in mining methods, notably the open-cut methods in which steam shovels strip off the overburden and then load the ore directly into railroad trains for transport to the furnace. In 1907 open-cut mining was applied to the low-grade copper ores of Bingham, Utah, with splendid results, and since then it has won a most important place in the min- ing of large masses of low-grade ores in several other mining regions, especially at Santa Rita, N. Mex.

Jan 1, 1916

By Robert W. Bartlett

Chalcopyrite in copper flotation concentrates can be hydrothermally converted to digenite with oxygen in a continuous process, with rapid kinetics when operated above 200°C. This eliminates large amounts of sulfur and iron. These "super-concentrates" have potential for debottlenecking smelters and avoiding capital intensive future smelter expansions, otherwise required in the late 1990s. The technology of producing super- concentrates is described, with cost estimates, and the use of super-concentrates as smelter feed is discussed, with examples.

Jan 1, 1992

Mr. BRADFORD said :-On assuming this chair, which has been occupied by so many gentlemen of conspicuous ability; my first words must be an expression of the gratitude I feel for the honour you have done me in electing me to be your President for this year.When considering the subject matter of this address to you to-night, quite frankly may it be stated that for a long time I was on the horns of a very great dilemma, for while I could discourse on the modern political trend in relation to our industries at great length, it appeared to me that this was not the place for such a discussion. Next I turned to a consideration of whether a discourse on the theory and practice of iron and steel would be of interest.I, however, banished this idea also from my mind, because it appeared to me that you have already had a surfeit of this on your visits of inspection to our local industries and I did not want in any way to be held responsible for the iron entering into your souls! I therefore propose, with your kind consideration, to address you on other subjects of common and vital interest to all.My first words and thoughts turn on the absolute necessity of eliminating waste in our methods. If we are to succeed in our...

Jan 1, 1926

In the Bendigo district, with its large number of comparitively small leases worked by separate companies, we might naturally expect to find many different arrangements of winding machinery and, as a matter of fact, there are steam winches, old portable engines, single and duplex geared engines, twin engines on the first motion, and in one instance a single engine on the first motion, all employed for hauling purposes from depths of 1000 feet and over.It would be impossible in the compass of this paper to discuss at all fully the various arrangements of winding gear employed on the field the writer can simply refer to some of the more prominent features, in the hope that the information may prove of interest and benefit to the mining community. In criticising our machinery it must be remembered that when many of the plants in use at the present time were erected, they were not intended to wind from more than one third of the depths now common on the field; but so long as the machine could be made to haul a tank of water from the bottom of the shaft it has remained, the greater power required being obtained by increasing the piston speed and altering the gear wheels to suit. The consequence is, of course, that in some of our mines the speed of winding is painfully slow this feature, however, though certainly not consistent with modern ideas of economical mining, does not so seriously affect Bendigo as it would other fields, for the comparatively small quantity of stone to be raised from a given reef by some...

Jan 1, 1902

By J. A. Berger, R. J. Towner

The pjPocesses of polygonization and subgrain growth were followed in slightly stretched 99.99 pct A1 single crystals heated for cumulative times at 400°, 500°, and 600°C. Changes in sub-grain size and boundary angle were determined from measurements on X-ray micrographs. CAHN1, 2 studied polygonization in stretched and heated aluminum single crystals of 99.99 pct A1 using various techniques, including etch pits, Laue patterns, and a slight restretching of heated specimens to reveal small changes in lattice orientation by the direction of new slip lines. He found that kink bands, which had well-defined boundaries lying in a plane perpendicular to the slip direction (at least in the early stages of deformation), formed during stretching. Also, he noted that bending occurred about the <211> axis lying in the (111) slip plane perpendicular to the <110> slip direction. His studies of polygonization were largely confined to the kink bands rather than to the weakly bent matrix regions between bands. The minimum temperature required to bring about polygonization was established at about 450 "C. Guinier and Tenevin used a focusing Laue X-ray diffraction technique to study polygonization in aluminum single-crystal specimens of 99.99 pct purity. Stretching the crystals 5 pct in tension caused a widening of the focused Laue spots. After heating for 4 hr at 450°C, their method revealed no change in the specimen. Above 450°C polygonization was detected and further annealing near 600°C led to subgrain growth. They concluded that the orientation of the crystal relative to the axis of deformation had no marked effect on polygonization. Gay and Honey-combe4 using an X-ray microbeam technique found that polygonization did not occur in a stretched aluminum crystal heated at 250oC, although some decrease in the yield strength occurred. When the temperature was raised to 475oC, the asterism became broken up as a result of polygonization. Honeycombe5 noted that reflections on X-ray mi-

Jan 1, 1961

[ ] ALVA L. SMITH RMCMI PRESIDENT 1989-1990 on behalf of the RMCMI Board of Directors and Officers of The Rocky Mountain Coal Mining Institute cordially invites you and your family to attend the 86th Regular Meeting and Convention to be held June 24, 25 and 26, 1990 at Sheraton Steamboat Steamboat Springs, Colorado

Jan 1, 1989

By G. Atesok

Turkey?s EU affairs started in 1963 with the Ankara Treaty. On 31 December 1995 the Customs Union between Turkey and the European Union came into effect. In order to achieve the Copenhagen Criteria?s, Turkey, made laws parallel to the Framework Programs. On 3 October 2005, with the confirmation of ?Membership Framework Document? the negotiation process of Turkey has started. Coal had important role in the industrialization of EU and it is directly related to Energy and Environmental subjects. In this point many restriction became with the some protocols, in last decades. European Union composed Energy and Coal Policy, therefore engaged to reduce the emissions, and made new regulations. This regulations concern Turkey?s energy future, since large; but low quality of lignite reserves of Turkey, it is expected to have some difficulties with Union?s Environmental Legislation during Turkey?s congruity process. With the last natural gas import agreements of Turkey, the production and consumption of coal sunk in last seven years. However, considering environmental sustainability, the role of coal in energy production will rise up in the coming future. In this paper, in terms of Turkey Energy Sector, production and consumption problems of coal discussed and evaluated considering EU?s coal, energy and environmental rudiments.

Jan 1, 2014

By W. J. Kotzé

Die derde colloquium van die Spesialiste-afdeling van die SAIMM is op 19 November 1980by die Universiteit van Pretoria gehou en is deur sowat 40 mense bygewoon. Dr J. P. Hugo tree as Voorsitter op en heet al die aanwesiges welkom, en stel elke spreker om die beurt aan die vergadering voor.

Jan 1, 1981

By Mustafa Kumral, Mehmet Balci

Strategic mine planning focuses on cutoff grade selection, capacity planning and block sequencing. Despite significant knowledge accumulated, potential value can be added to mineral sourcing by addressing various aspects. A case study on a metallic deposit with a lognormal grade distribution examines if grade/metal distribution influences cutoff grade selection. Six data sets with different shape and scale factors, but the same ore tonnage and metal quantity, are analyzed. Results indicate deposits with lower shape and scale factors are more sensitive to metal price and discount rate changes. The study also investigates the effect of economies of scale (EoS) on project value, focusing on the ratio of variable cost to total cost (capacity factor). Two regression analyses are conducted for optimal capacity planning and cutoff grade selection. The first shows capacity planning is highly sensitive to the EoS of mining and mineral-processing costs, with grade variability and metal distribution being negligible. In the second analysis, grade variability and EoS of mineral processing costs are vital for cutoff grade selection.

Sep 1, 2024

By Fouad Faraj

For every blast pattern, zones of unique material types need to be classified before mining. Most material types can be summarized into different kinds of ore and waste. Blocks generated from blasthole assays are too small to be selectively mined, so areas with a single material classification meeting the mine’s selective mining unit must be defined. Current industry standard practices are to manually draw ore/waste dig limits, but this process is subjective and results in quantities of dilution and ore loss that can be improved upon to enhance the profitability of mining operations. In this study, two weeks of production data from a homogeneous copper (Cu) porphyry and heterogeneous manto-type Cu deposit were used to assess the variability in the hand-drawn dig limits of 20 geologists, mining engineers and ore control specialists, which were compared with the optimal ore/waste delineation. The profit for 20 distinct hand-drawn dig limits for the homogeneous mine varied by 3.7 percent, from $10.5 million to $10.9 million, averaging at $10.8 million. The percentage was nearly double for the more heterogeneous mine at 5.9 percent, from $17.9 million to $19.0 million, averaging at $18.6 million. Using the optimal ore waste delineation, the profit increased to $11.0 million (1.9 percent increase) and $19.3 million (7.0 percent increase) for the homogeneous and heterogeneous deposit, respectively. The natural variability, diggability requirement and selectivity are identified as the main drivers of ore loss and dilution. Recommendations are provided for reducing the subjectivity in manual hand-drawn dig limits by integrating dig limit optimization algorithms as a tool to assist practitioners.

Oct 1, 2024

[This Report represents the culmination of work perfomed under Contract No. .,JG1551A8 for the U.S. Bureau of Mine.The &apos;.:o-< embeded a site evaluation, engineering E:-y- ,, esign, and preparation of specifications for construction of a Transport Research 7 :4 (HTRF)The HTRF is designed as a research facility J evaluate the hydraulic transport of large lump coal at a prototype ;e scale. The HTRF is to be constructed and operated by the Pittsburgh and Safety Research Center of ;. re U.-AN a*, their Bruceton, Pennsylvania test center. In terms of technical capability, the HTRF will have transport pipeline:: of -, twelve-, and eighteen-inch diameter _&apos; with supporting coal handling n , water forage a.^ &apos;d conveyance, mixing, pumping, and dewatering equipment, plus instrumentation and controls. Maximum design velocity 13 20 ft/sec.; solids concentration, by, volume, will; 1 be a maximum-- of sixty, percent. Each test loop is designed to accommodate solids of up to one-third the diameter e - of the pine. The Final Report Pr.-&apos;I-rents information of t HTHF,. including the site evaluation, design criteria, a description of the a description of the procedure to be used for operation of the facility, an estimate of the cost to construct the f^Cilit:r, 1 p el_~lli.&apos;iU construe`, icn Schedule, and a construction suicJ_iicaT.l_ccn&apos;. T e c011SLr?Jc&apos;.ion soecl_ i.on _ccnta_i:s technic.&apos;..i re7,uir: (-n`,s for !&apos;urr1S~ &apos;~latcr..al. and ec-uipr,ent for :":C1 C_`:_C ti on of ti,_ H ice&apos; u:&apos;.:i ._II u s(-.6 for ~.Iir: .3!7 soliciting bids. `.l_o included n cc&apos;;,art_- c?r~.air sV:et..: :s ^nd rr^.?]

Jan 1, 1976