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By F. Matanzo

[Nine wire rope terminations were pull tested and fatigue tested to destruction to measure the termination efficiency and relative fatigue life. The terminations were selected on the basis off mine site visits and the specimen were assembled in a manner similar to industrial slings. To measure a termination's sensitivity to poor workmanship, both standard and modified assembly specimen were tested. Lang and Regular construction of the 6x19 and 6x37 class wire ropes were used in diameters of 13 mm (1/2 in.), 19 mm (3/4 in.), 25 mm (1 in.), 38 mm (1 1/2 in.), and 51 mm (2 in.). In static pull tests rope class, construction, and diameter interacted with the termination to influence the efficiency of the termination. In axial fatigue tests using only the 6x19 class rope, the effect of rope construction was negligible since failure was primarily dependent on the termination type. The Swaged Socket, a termination requiring a high capacity hydraulic press, gave the best overall performance in terms of efficiency and fatigue life. The short body length of the Zinc Poured Socket (RR-S-550) was attributed with the short fatigue life of this termination. The use of thermosetting resins as a replacement for zinc was demonstrated successfully for some socket designs. The fatigue life of the termination, expressed as a percentage of the fatigue life of the wire rope, was shown to be a guide for the retirement of the wire in these applications where the wiry' rope is primarily in axial loading.]

Jan 1, 1978

By Roberto Antoniolli

"IntroductionSINCE ancient times, the precious metals have played an important role in influencing the course of history. Silver and gold happened to occur, although in small amounts, in those countries where the early civilizations developed. Their persistent brightness certainly amazed the primitive people, who also found it easy to shape them into ornaments •and implements. Ever since then their properties have made them seem desirable possessions.Use of precious metals as money was the natural consequence of man's desire for them. The possibility of changing an ornament into a tool or food at any time, and the ease with which such medium of exchange could be carried and hidden, further increased the demand for the two metals.Silver was probably discovered after gold and copper, and was undoubtedly found by prehistoric man as native silver. The oldest silver articles have been discovered in Chaldean tombs and date back to 5000 B.C. The earliest ascertained producers of silver were Asia Minor and the Iberian Peninsula. The Romans worked deposits in Spain, Britain, and France. In the Middle Ages, some silver was extracted from German deposits, and near the end of the Middle Ages systematic workings were carried on at Freiberg, Schneeberg, and Joachimsthal (1).Before the discovery of the New Continent, the Aztecs and Toltecs in Mexico, and the Incas in Peru, had made extensive use of silver. In the 16th century the Mexican deposits became the largest source of the world silver."

Jan 1, 1954

By George S. Rice

Foreword Explosion hazards differ widely in the mines of different fields or coal basins. They also differ as between different mines in the same basin or fold, because of variations in gas entering the mines, and because dust conditions and explosion hazards are affected by the mining methods employed and the organization of the work. It is unquestionably true, however, that there are greater differences in explosion hazards in mines of different coal fields or basins than between different mines of the same field or basin. In these respects, the coal fields and individual mines in Alberta are not exceptional. The same conditions obtain in various countries where coal is mined, and are found in single States, as for example in Colorado, where coals are mined ranging in character from sub-bituminous to anthracite, and in attitude from flat horizontal to steeply pitching beds. The U.S. Bureau of Mines, at its experimental mine near Pittsburgh, Pa., has made large-scale tests of the relative explosibility of dusts of coals, ranging in rank from Wyoming sub-bituminous coal containing 19 per cent moisture, to anthracite from Pennsylvania, and including samples from a mine in the Crowsnest Pass district, B.C., and from a Vancouver Island mine. The Bureau has also made similar tests of the dust of coal from a Yorkshire mine which the British Safety-in-Mines Research Board uses as standard.

Jan 1, 1927

By M. A. Trevits, T. A. Gray, L. M. Crayne, P. Glogowski

Mine seals can he remotely constructed in underground coal mines through vertical boreholes when direct access to a fire is impossible or considered to he too dangerous. This method has great merit because the boreholes can be drilled to specific mine areas, and the seals can be positioned close to a fire zone. The technology however can be largely ineffective if the constructed seals do not provide of effective barriers to airflow or if they cannot he used to impound water and other inert materials. Unfortunately, no viable alternatives exists to sealing the entire mine to the ground surface. Full-scale remote mine seal construction research is being conducted at the National Institute for Occupational Safety and Health (NIOSH) Lake Lynn Laboratory (LLL). Under this effort. Howard Concrete Pumping Company and GAI Consultants Inc. have joined forces to evaluate a potentially significant improvement to the current state of the art. This paper covers the development o f novel technology or rewrote mine seal construction, the evaluation of rite materials used, the construction practice and the Fellow-up testing.

By B. Moore, Y. J. Zhang

In today’s competitive dimensional stone business environment, use of available technology is critical to achieve and maintain a competitive advantage. Awareness of improvements in diamond cutting technology, operation planning/scheduling, and geotechnical data manipulation/implementation are the keys to success. This paper presents the modern techniques of limestone sawing and quarrying developed and adopted by Indiana Limestone Company, Inc.(ILCI).To fulfill the growing market demands, ILCI’s quarries are committed to deliver planned quantities of all type of stone blocks in a variety of different colors, sizes, and textures. This involves scheduling which quarry ledges should be mined and when in order to minimize unnecessary inventory buildup. Challenges associated with ILCI’s operation are discussed and summarized in the closing of this paper.

Jan 1, 2004

By P. J. Bourassa

Incorporated in 1957 under the laws of the Province of Quebec, Quebec Cartier Mining Co. undertook the development of its low-grade iron ore reserves located at Lac Jeannine in the southwest extremity of the Quebec-Labrador trough. This challenge comprised the construction of a 200-mile access road, two towns, a 191-mile-long railroad from Port Cartier to Lac Jeannine, a hydro-electric generating plant on the Hart Jaune River, and mining, crushing, concentrating and ancillary facilities to support a yearly production of 8.0 million tons of iron ore concentrates at 66% Fe. In order to meet increasing market demands for iron ore concentrates concurrently with the depletion of its Lac Jeannine reserves , Quebec Cartier announced, late in 1969, the first step toward bringing into production a new iron ore deposit, known as Mount Wright, located 70 air miles northeast of Lac Jeannine and 25 miles southwest of Labrador City, Newfoundland. In September 1970, the company announced its decision to develop and bring into production its Mount Wright reserves at an annual rate of 1 8.4 million dry long tons. The scope of this project included the construction of an access road linking the mine, the new town and Labrador City, Newfoundland, the extension of the railroad by some 86 miles, the construction of an ore concentrating plant with all the ancillary facilities, the development: of the mine, the construction of a pourer transmission line and a new town adjacent to Lake Daviault. The Mount Wright story is divided into five individual papers covering: (a) the history and development of the project; (b) the mine; (c) plant control by a process computer; (d) crushing, grinding and concentrating; and (e) the townsite of Fermont.

Jan 1, 1977

By R J. Goldie

The Monty Copper Gold Deposit is an ultra-high grade mine in Sandfire Resource’s Doolgunna region which was completely drilled out and developed within two years of commencing mine development. During this period, a total of 986 grade control diamond drill holes were completed, assayed, and validated, 15 levels developed, and 3136 faces mapped. The aggressive schedule meant a high flow of geological data was produced, validated, and incorporated into regular geological model updates. To process this data at a rate which allowed for timely use, more robust data processing methodologies needed to be generated. A new validation system was implemented which required two levels of validation being applied to any diamond drilling update. Step one was the validation of initial physical data including survey pick-ups and logging. This was done prior to new drill data being added to the geological model. Step two was the validation of assay data which was required prior to resource estimation. The implementation of Seequent’s Leapfrog Geo modelling software also allowed for a more seamless and efficient modelling workflow. The use of the Leapfrog Geo vein systems allowed for more rapid generation of geological models which then afforded more time for stringent assessment of the mineralisation system. An example of this was the introduction of cross-shift peer reviews in which opposing rosters of geologists would rigorously evaluate the previous rosters work prior to reporting. This additional level of validation resulted in more robust geological models and the identification of new ore trends. This presentation will detail the evolution of the Monty Geological model from a simple tabular indicated resource into a complex highly refined measured resource. Themes will include how the model was produced using workflows developed and optimised to meet key deliverables.

Mar 22, 2022

By B Clemen, D Gordon, F Cesnik, P Griffin

In March 2002 Newcrest Mining Ltd commissioned a 4 Mtpa gold-copper concentrator at its Cadia Valley Operations in New South Wales. This paper presents the design and construction considerations, commissioning and ramp up issues related to start up of the concentrator as well as current performance and future expansion plans. Commissioning of the plant was the culmination of six years of project planning, from discovery of the resource during the Cadia Hill drill out campaign in November 1996 to project implementation and plant operation. Current resource estimates stand at around 50 Mt with an average grade of 2.4 g/t gold and 0.8 per cent copper. At current processing rates the project life is expected to exceed ten years. The processing plant comprises a 9.75 m (32 ft) diameter Fully Autogenous (AG) mill, a single 6.7 m (22 ft) diameter ball mill, pebble crushers, gravity gold recovery circuit and flotation plant. Upgrades to the existing infrastructure and manning requirements at Cadia will be discussed as well as the resultant impacts on operating costs for the operation. The processing plant was expected to deliver 290 000 ounces of gold and 30 000 tonnes of copper in concentrate in its first full year of operation and progress against that goal will be presented.

Jan 1, 2003

By S. Fuentes, J. Cáceres

"During the past fifteen years, mines utilizing the block caving method have improved performance and systematically reduced total mining costs.This paper describes improvements in mine design, mine planning, and mine management, including methods enabling the Chilean and international mining industry to ensure cost savings and productivity growth while using the block caving method. These improvements have encouraged the re-evaluation of underground operations at operating and closed open pits, and challenge surface mining applications as the only low-cost mining method. This paper describes a strategy to estimate the optimum open pit to underground transition time during the life of a mine. IntroductionDuring the last fifteen years, block caving mines have experienced huge changes in designs, planning and administration. These changes have permitted operators to drastically reduce costs, improve equipment productivity, and improve overall business performance. As a consequence of this situation, the block/panel caving mining system is challenging actual open pit operations to maximize the net present value (NPV)."

Jan 1, 2004

By Sushil Bhandari, Amit Bhandari

Blast optimization in open-pit operations is a task that often remains at a theoretical stage. Indeed, when it comes to operational blast design and onsite implementation, time restrictions and field conditions make it difficult to execute a planned pattern accurately and optimization according to local conditions is even more difficult. For example, adjusting a drill pattern to a complex face geometry is not something that can be easily undertaken on site. Blasters and engineers will do their best trying to distribute boreholes over the bench and even then, it can take them hours to achieve an acceptable layout. Similar situations occur with delay sequences, when trying to adjust them to address selectivity or vibration issues. For these reasons, operational blast design will often remain at a very basic level and the required adjustments are laid aside due to the difficulty of implementing them on site.

Jan 1, 2019

By Thompson D. R, Milton R, Perry K. M A

From the Department for Research in Industrial Medicine (Medical Research Council), The London Hospital; and the De Havilland Aircraft Company:M.R.C. INVESTIGATIONS IN 1936In 1936 the Industrial Pulmonary Disease Committee of the Medical Research Council investigated both clinically and radiologically a group of fifty workers who had been exposed for a number of years to the inhalation of alumina in the reduction factory of the British Aluminium Company. The results are shown in Table 1.They also considered the sickness records of all the workers (Hill, 1936), as compared with those in other parts of the factory (Table 2).

Jan 1, 1945

By C. Steve Albrecht

The primary objective of this study is to "evaluate the influences of different equipment systems on prime farmland subsoil compaction due to surface mining in the Midwest." The study is centered on four mine sites each utilizing a different combination of equipment for soil removal and replacement. Subsoil compaction is the primary focus of this research effort. Primarily owing to physical location, it is difficult to alleviate the increased compaction directly below the topsoil in reclaimed soils. Different equipment combinations cause varied effects when soils are replaced during surface mining activities. By collecting field data within a statistical framework, the effects of different equipment combinations on subsoil compaction can be evaluated and conclusions drawn. This research effort evaluates a comparison of natural and replaced soils by moist bulk density data. This comparison centers on changes in bulk density and texture to a depth of 48 inches. For each study site a complete case study is provided for use in data correlation and interpretation. Basis for this research effort centers on four (4) major experiment designs: o Comparison of soil bulk density values for three distinct equipment systems evaluated on the same general soil types (i.e. scrapers, bucket-wheel excavators and end-dump haulback); o Evaluation of the effects of soil replacement in repeated lifts using scrapers; o Presentation of bulk density values representing soil compaction for four (4) equipment systems (i.e. bucket-wheel excavators, draglines, scrapers and end-dump haul back) on four separate mine sites in the midwest; o A prediction analysis model is developed for subsoil bulk density following reclamation based on equipment characteristics and a statistical evaluation of texture. The soil data base of information includes data from the 1982 Bureau of Mines study entitled, "Impact of Surface Mining on Soil Compaction in the Midwest" as well as data from this research project. The final report is synthesized through an analysis of field data, statistical analysis and literature review. The final report focuses on the interpretation of results for practical application by government and industry.

Jan 1, 1984

By P. Pyykkö, E. Peuraniemi, J. Järvi, P. V. Latostenmaa, V. Törölä, S. Junnikkala

"Nickel concentrate smelting started in Harjavalta in 1959. First, flash smelting - Peirce-Smith converting route was applied, and the high-grade converter matte was further refined to nickel cathodes. In 1995 the original smelter flow sheet was simplified with the novel DON (Direct Outokumpu Nickel) technology. In Harjavalta with the DON technology, high-grade nickel matte with low iron content is produced in flash smelting furnace directly without subsequent converting stage. The metal values in the smelting slag are recovered in an electric furnace as an iron containing bottom alloy. Main special features in Boliden Harjavalta nickel smelter are smelting of high-magnesia concentrates, the high recoveries of nickel and copper, as well as those of PGM`s and cobalt.Sulfur and dust emissions to air can be seen generally as one main disadvantage of nickel smelting operations. In Harjavalta continuous improvements in environmental performance has been rewarded by minimum sulfur and dust emissions to the environment and working atmosphere. Today Boliden Harjavalta’s nickel smelter is presenting state-of-art-technology at nickel smelting.This paper describes the nickel smelter process and includes recent production and emission data. It describes features required to achieve environmental and occupational hygiene goals and compares environmental performance data to that published on other smelting operations. General description of New Boliden Way is presented and a case example of production stability project is also presented."

Jan 1, 2014

By Richard A. Dick

Eight blasts were fired in a 2-1/2-ft bench in the Stewartville member of the Galena Limestone formation in an aggregate quarry near Stewartville, Minn. The shots were dimensionally proportional to production-size bench blasts and were about 5 to 10 percent of full scale. The effects of site, timing of initiation, and burden-to-spacing ratio were studied in a 2 x 2 x 2 factorial experiment, using three boreholes, caw;, containing a 1/2-in charge diameter of high-density ammonia dynamite, in each blast. Detonation velocity measurements indicated that the dynamite detonated satisfactorily in the 1/2-in charge diameter. The effects of the three experimental variables were analyzed by weight for the percentage of oversized material produced and for size distributions determined by screening the entire muckpiles. The bench faces were painted before each shot in an effort to determine the origin of the oversized material. The square pattern (burden and spacing = 15 in) produced finer overall fragmentation and less oversized material than the rectangular pattern (burden = 15 in; spacing = 22-1/2 in). Sites 1 and 2 were about ft apart. Although site 2 produced slightly better overall fragmentation than site 1, the amounts of oversized material produced showed no significant difference. The timing of initiation (instantaneous or delayed) did not significantly influence the overall fragmentation or the amount of oversized material produced.

Jan 1, 1973

By Holly J

The period following World War II has seen many changes in stoping techniques at The Great Boulder Gold Mine. The new methods resulted in improved unit production figures, and have given some relief from the rising worldwide cost spiral in the post war years.Significant production figures are shown graphically in...

Jan 1, 1956

By Jack C. Haptonstall

This paper describes the analytical characteristics of Western subbituminous coal and the manner in which these characteristics apply to their use in a utility-sized steam generator. It compares these characteristics with those of typical Midwestern coal and Eastern bituminous coal. The paper also reviews in detail the design considerations that must receive attention when various blends of these three coals, or any combinations thereof, are planned to be used. This research paper describes variations in analytical and utilization characteristics when coals from different origins are blended in order to achieve a predetermined sulfur content for the purpose of predicting sulfur oxides emissions as they affect environmental regulations and the resulting alterations in utilization characteristics such blending would cause, and how such blends of coal would affect a utility-sized steam generator.

Jan 1, 1979

By F. S. Crawford

Although it may be impracticable to adopt standard methods of safe working in all branches of mining, and although it may be impossible to establish a standard for each class of work at each mine, some of the iron-mining companies in the Lake Superior district have found that by adopting certain standard ways of performing certain of their operations they insure both more efficient and safer working conditions. Many companies have adopted the idea that the safe way of doing things is also the most efficient and economical way, and, through the medium of their safety conferences they are trying to find the safest way, and the most efficient way, of performing practically every operation about the mines. This activity will, undoubtedly, be continued at every operation which uses this method of doing safety work, because in the advance of industry changes must be made in the results required from time to time. A review of the safety standards and safety suggestions which have been arrived at by some of the companies in this the greatest iron-mining district in the world, will be of value to companies who are interested in improving the safety of their working conditions. So that attention may be directed to the methods in use, rather than to individual companies, all names have been omitted and companies are referred to only by letter.

Aug 1, 1931

By William Paxton Hewitt

Mineral deposits of western Utah and eastern and central Nevada have produced in excess of $8,500,000,000 since 1871. Through 1965, Bingham Canyon had produced over $4,600,000,000 and seven other camps over $100,000,000 each, principally from base metals. In addition, they yield iron and uranium ores; contain the world's largest beryllium reserves; and have produced the United States' most important gold discovery in 25 years. The area is famous for its silver production and its bonanza-type precious metal deposits, but such production has become unimportant. The area's greatest producers of metallic wealth are base-metal deposits in limestones and porphyry-type copper ores. In contrast to silver's decline, gold production has been rising-the result of by-product operations at Bingham Canyon. The area also contains gold deposits in which the gold is so finely disseminated it is not recoverable by panning. The area's gold ores frequently are associated with realgar, cinnabar, and carbon. The ore deposits generally are attributed to Tertiary intrusives,* but, at Mountain City, they may be related to Paleozoic volcanism. Mountain City has yielded rich chalcocite from quartz-pyrite-chalcopyrite bodies in siliceous sediments. Regional stratigraphy and structure are difficult to interpret, 69 per cent of the area being obscured by alluvium or volcanics. In general, central Nevada consists of chert, shale, silty sandstones, lavas, and pyroclastics; eastern Nevada and western Utah of many alternations of limestone, shale, and sandstone. Central Nevada has been structurally active since late Devonian. Although granitic stocks may have intruded eastern Nevada and western Utah prior to the Cretaceous, these areas remained quite stable until affected by the Laramide Revolution. Precambrian exposures, occupying 3 per cent of the area, have not been important hosts. However, the question is raised as to whether Precambrian carbonates, properly situated with respect to invading mineralizers, might yet prove to be important. This paper describes 16 precious metal camps, 6 limestone replacement districts, 2 silver-base metal vein deposits, and 9 miscellaneous types and discusses briefly the 11 * Some ores, as at Ely, are associated with intrusives of. Cretaceous age. major camps that are described in detail in this Volume.

Jan 1, 1968

By D. C. Sharpstone

THE Polaris-Taku mine is a new gold property, situated in the far north-west corner of British Columbia. Production was started in November, 1937, at the rate of 150 tons a day, and recently has been increased to 200 tons. The property, which promises to become one of British Columbia's important gold mines, was developed and brought into production in twenty-nine months after work was started on it as a virtual prospect in June, 1935, by Edward C. Congdon and associates. Inaccessibility, extraordinarily complicated geological problems, and difficult metallurgy retarded development of the property before acquisition by the present interests, an::l, in fact, discouraged two companies that had spent substantial sums upon it from continuing development. This paper is concerned with reviewing the development of the property and describing the principal features of the geology, the mining and metallurgical practices, and the equipment employed. Acknowledgments The writer is indebted to Mr. Edward C. Congdon, President of the Polaris-Taku Mining Company, and to various members of the mine staff for their assistance in assembling the data for this paper. Special thanks are due to Mr. George G. Griswold, Jr., of Butte, Montana, who generously and painstakingly prepared the section dealing with milling and power. Microscopic studies of ores were made by Professors Frank Grout an::l G. M. Schwartz, of the University of Minnesota, and by Mr. Griswold.

Jan 1, 1938

By J. E. Dutrizac, J. B. O'Reilly

"Zinc is a relatively abundant element which occurs as both high-grade sulphide ores {sphalerite ZnS) and oxide ores which the ancients collectively termed ""calamine"" (smithsonite ZnC03 and/ or hemimorphite Zn4Si201(0H)2 - H20 and/ or hydrozincite Zn5(C03) 2(0H)6). Although oxidic zinc is readily reduced by carbon, the process becomes thermodynamically viable only at - 1000°C, and at this temperature the zinc is released as a vapour (B.P. 907°C). Casual cooling of the vapour results in its re-oxidation by excess combustion air or even the carbon monoxide product of the reduction reaction. ZnO + C = C09,, + Zn vapom Only fairly rapid quenching of the zinc vapour and the isolation of the reduction products from the combustion gases will yield metallic zinc; these conditions were not produced deliberately until the advent of distillation technology. Until quite recently, the principal use of zinc was in brass manufacture; galvanized iron was not discovered until the 19th century and zinc casting alloys are a relatively recent invention. As will be seen, brass could be produced without recourse to a pure zinc intermediary, and the discovery of brass preceded that of zinc by many centuries. The purpose of this paper is to outline the discovery and early development of both zinc and brass with special reference to the European scene."

Jan 1, 1999