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By Paul M. Tyler, R. M. Santmyers

Platinum and its allied metals osmium, iridium, rhodium , palladium, and ruthenium are the most costly of the better-known metals and combine properties that make them unique among the elements . For a number of isolated uses substitutes have been found which are cheaper and quite as satisfactory ; but none will replace platinum in many of its varied uses , and there is a large and growing demand for purposes for which no economical substitutes are known . As this paper is being written the supply of platinum tends further to increase as a result of the exploitation of newly developed resources and the expansion of production from older sources . In obedience to economic law prices have declined steadily . Buyers , always reluctant to commit themselves on a falling market , have maintained a waiting attitude , and consumption trends are not clearly indicated . Should platinum again approach the price of gold , the natural tendency would be to use more of the metal . In recent years , however , the industrial and scientific uses of platinum have become subordinate to its consumption in jewelry . In matters of personal adornment the popular whim and not practical utility is the dominant factor in demand , and it does not follow that lowered prices will stimulate demand . The substitution of white gold and certain plated goods for platinum may be checked by cheaper platinum , but a fickle public that turned from gold to platinum when platinum became the more costly metal can not with certainty be expected to buy more platinum jewelry because more of the metal than formerly may now be had for the same price . The dearth of platinum during and for some years after the World War had a profound effect upon prices , and this in turn wrought important changes in the field of consumption . When prices advanced the chemical industry, formerly the leading consumer of platinum, was forced to economize in its consumption of the metal and to substitute other metals whenever it could . Somewhat similar conditions resulted in the electrical industry and in the use of platinum in dentistry . Some of these former outlets are permanently closed , and others may be reopened now that platinum prices have receded to pre-war levels , but despite the general expansion of industrial and scientific activity since 1913 the demand for platinum outside the jewelry trade has suffered a net decline . Since the metallurgy of platinum is relatively simple the reason for its high price is its relative scarcity in the earth's crust . An interesting speculation set forth by certain geologists attributes the extraordinarily high density of the interior of the earth in part to the presence of iron alloyed with substantial amounts of platinum and other related metals . In support of this hypothesis it may be said that platinum is often found in meteorites , and known deposits in the earth's crust are all of deep - seated origin . However , even if there were a high concentration of platinum in the interior of the earth it would be next to impossible at the present state of our knowledge to make it available , and the world would continue to depend for its supply on deposits found within minable depths below the surface . For many years before 1914 the world obtained its supply of platinum metals primarily from Russia , which before the war produced as much as 300,000 troy ounces in a year , or approximately 95 per cent of the world output . Despite fluctuations due to internal political disturbances Colombia managed to account for 3 to 4 per cent , leaving the rest of the world to furnish the remaining 1 to 2 per cent .

Feb 1, 1931

By Walter Koellner

Today?s large electric mining shovels are significant users of power and represent peak loads of more than 3.5 MW to a mine?s distribution system. The power swings during normal operation can influence the line voltage at the Point of Common Coupling (PCC). The static converters for the shovel?s motions also create voltage and current harmonics which are fed back into the mine?s power grid. In addition, shovels themselves are affected by the power quality of the mine?s distribution system. This paper introduces the use of active IGBT rectifiers, also called Active Front Ends (AFE), as alternative to conventional, line commutated SCR thyristor rectifiers. The AFEs convert the AC line input into a controlled DC-link voltage. This DC voltage is then used as input to IGBT inverters, which power the AC motors of the shovel?s Hoist, Propel, Crowd, and Swing motions. The introduction of AFEs creates the following operational improvements: i) reduction of the Harmonic Current Distortion THDi from more than 40% to less than 4%; ii) full regenerative operation; iii) the potential for line voltage stabilization at the PCC; iv) high tolerance for line voltage fluctuations; v) improved dynamic performance, and, as result vi) higher availability and productivity of the shovel.

May 1, 2001

By Charles Camsell

At the Annual General Meeting of the Institute in 1924. I endeavoured to present the position held by the mineral industries in the commercial life of this country. The facts and figures were presented at that time in a detached way. Since then, however, I have made some attempt to analyze them in order to determine the causes for that position and to draw some conclusions as to the future of the mining industry. As everyone knows, our trade figures are very often used in political discussion, especially in discussion of tariff policy. It would be entirely out of order for me to say anything touching the tariff issue and I want to have it clearly understood that, in my opinion, the material I am about to present contains not a single statement or conclusion which anyone would be warranted in using as an argument for either a lower or a higher tariff or for tariff changes of any kind. As a starting point, let me re-state, very sketchily, Canada's general situation in external trade. In the last calendar year, 1924, we sold Canadian merchandise of all kinds to other countries to the value of $1,045,000,000 in round figures. Our purchases abroad reached about $893,000,000. Thus our sales exceeded our purchases by roughly $152,000,000. In other words, we had what is known as a 'favourable balance of trade' - one of the biggest favourable balances we have ever had in our history. The proceeds of our sales of Canadian products enabled us to meet the bills for all our purchases of foreign commodities and, in addition, placed a large surplus to our credit with which to offset our interest charges and other obligations abroad.

Jan 1, 1925

By Philippe Poirier

Les parcs à résidus miniers représentent un risque environnemental qui nécessite une gestion adéquate. Suite à la publication du « Guide sur la gestion des parcs à résidus miniers » en septembre 1998, les membres de l?industrie minière ont appliqué les éléments de gestion du Guide, permettant ainsi une amélioration continue des opérations. En février 2000, l?industrie minière a indiqué le besoin d?établir des lignes directives plus spécifiques pour l?opération sécuritaire des parcs à résidus. Dans cette optique, l?Association Minière Canadienne a publié, en septembre 2002, un Guide pour l?exploitation, l?entretien et la surveillance (EES) des parcs à résidus miniers. Suite au développement du Guide et à son application sur plusieurs sites miniers, il apparaît que la mise en oeuvre d?un Manuel ESS des parcs à résidus miniers permet : ? d?établir les responsabilités des intervenants; ? de s?assurer que les critères d?opération sont appliqués; ? de mettre en oeuvre le plan de déposition des résidus et de gestion de l?eau; ? de rencontrer les normes et exigences environnementales; ? de définir un programme d?entretien et de surveillance des ouvrages; ? d?identifier les risques et de mettre en oeuvre un plan d?intervention d?urgence; de démontrer une opération diligente.

Nov 1, 2002

By W. J. S. Craigen, G. E. Wittur

"In the context of today's continuously changing world, there are many factors which must be considered when attempting to assess the ability of Canada's primary copper producers to remain competitive in the face of increasing competition in world markets. In this paper, we have attempted to document those factors that will have the greatest impact on the future viability of Canada's copper industry, and to suggest possible strategies to fully utilize whatever inherent advantages Canada may have to enhance its competitive position. Technological factors related to the efficiency of precious and by-product metals recovery, energy type and utilization efficiency, production and sale of sulphur by-products, and control of 502 emissions are given high priority in this evaluation of Canada's future needs to remain competitive. Particular emphasis is placed on assessing the relative viability of hydrometallurgical versus pyrometallurgical processes for copper; to address uniquely Canadian conditions and problems. Due consideration is also given to the economic incentives required to allow Canada's copper producers to compete under anticipated world market conditions and to facilitate the continued development of Canada's copper resources. IntroductionWhen we try to assess the viability or competitiveness of any industry the bottom line is still usually, ""Can we produce a pound of product cheaper than the competition?"" Canada's copper industry is certainly no exception. However, as with most resource-based industries dependent upon exports, there are many factors which have a significant effect on the cost components which make up the total cost of producing and selling a pound of copper. It is desirable therefore to have as clear a picture as possible of the cost components, the major factors affecting them, and how they compare with the competition, particularly the third-world copper producers.In this paper we have attempted to provide a brief outlook for world copper markets and a brief overview of Canada's competitive position. We have also attempted to document those factors which will have the greatest impact on future production costs, and have suggested possible initiatives to utilize inherent Canadian advantages to enhance our competitive position. Special emphasis has been placed on technological initiatives designed to make full use of these ""advantages"", to develop superior beneficiation and extraction! refining technologies. Major factors considered in the present study are:"

Jan 1, 1986

By W. R. ARGYLE, R. A. SHERMAN, Henry Kreisinger, John Blizard, B. J. CROSS, A. R. Mumford

On entering the World War the United States was confronted with the necessity of building in a short time a large number of ships of tonnage adequate to transport troops and war materials to Europe and to carry food supplies to the allied countries, whose merchant fleets had suffered greatly by submarine warfare. The necessity of building ships quickly led to the formation of the United States Shipping Board, which was charged with the duty of developing an efficient organization for the purpose. Such an organization was developed under the name of the Emergency Fleet Corporation; it was under the control of the Government, but could conduct its business in the most direct way, like a private corporation. In order to build the largest- number of ships possible without drawing too heavily on the steel industry, which was already taxed heavily by the production of munitions, it was decided to build wooden as well as steel ships. These ships were built from a few standard designs to enable a large number of duplicate parts to be fabricated in inland shops and transported by railroad to the shipyards on the seacoast, where they were assembled into ships. In other words, the plan was to manufacture the ships rather than to build them. The shops on the seacoast were reserved to make those parts of the ships' equipment that could not readily be transported. The inland shops made the parts that could be transported to the seacoast by railroad. Among the more important parts of the ships' equipment to be standardized were the boilers. As the Scotch marine boiler in large units is bulky and can not be transported by railroad, and as, for the same capacity,much more steelis needed in its construction than for water-tube boilers, a few simple designs of water-tube boilers were developed that inland shops having ordinary equipment could make in large quantities.

Jan 1, 1924

By V. F. Parry

The object of this report is to present certain pertinent data on the physical and chemical properties of South Arcot lignite and to present the results of several special tests to show how the raw lignite can be upgraded to superior fuels for certain special uses. The Bureau of Mines Branch of Coal Technology laboratories at Denver have advocated the drying and carbonization of all low-rank fuels for special uses and have introduced and developed new techniques for upgrading and refining noncoking coals. Application of these techniques to the South Arcot lignites was the object of the investigation, and this report presents significant data necessary for planning a fuel program based on utilization of dried and carbonized dusts. In general, the South Arcot lignite is similar in chemical properties to the high-moisture lignites found in the United States and has some physical properties similar to Australian brown coals. The samples submitted for test had lost moisture before delivery to the laboratory, and it has been necessary to estimate the analysis of the lignite in place in the mine. Various observations made in India by qualified technicians indicate that the bed moisture content of the entire seam is in the range of 54 to 56 percent. For estimating purposes in this report, the bed moisture content has been taken as 56 percent and the ash content of the fresh coal as 2.5 percent. The average analysis estimated for the as-mined lignite is: [Moisture percent 56.0 Volatile matter do.22.0 Fixed carbon do.19.5 Ash do.2.5 Heating value B.t.u. per lb. 4,890]

Jan 1, 1957

The Bureau of Mines is responsible for a broad spectrum of programs for meeting the diverse and changing mineral resource needs of the Nation. These programs are managed by the Director and two Deputy Directors, who formulate general policy and program direction from the Washington, D.C., headquarters. A senior advisory staff, consisting of the Chief Staff Officer, Chief Scientist, and Chief Mining Engineer, provides advice and consultation to the Director on a wide range of scientific and technical matters and acts on behalf of the Director to maintain liaisons with other government agencies, mineral industries, and professional societies. Bureau program activities are classified into two major functions: (1) Developing new and improved technology that will make the production and processing of minerals more efficient, safer and more healthful for mineral workers and the public, and more compatible with a quality environment.

Jan 1, 1980

By Serge Rudchenko

A study to determine the potential use of retaining structures in open pit backfilling. Research and review of the open pit mine environment, mine waste disposal, and past and current use of retaining structures. A development of specific structures, the culvert/ tunnel concept, and an anchor block retaining concept. The cost benefit of retaining structures used for in-pit backfilled waste.

Jan 1, 1981

By G. R. Hopkins

Although many small refineries were dismantled in 1934 the total number of plants, including a few under construction, increased from 604 at the beginning of the year to a new high of 638 on January 1, 1935. The capacity also reached a new record, the total of 4,072,400 barrels of crude oil daily being about 45,000 barrels higher than the previous high of January 1, 1932. The number of refineries increased materially in 1933, following construction in east Texas and the building of many small plants in the Rocky Mountain district and elsewhere. Most of the new plants of 1933 were built to provide an outlet for crude or because the ratio between crude oil and gasoline prices appeared conducive to profits However, low gasoline prices and increased costs in 1934 dispelled the hopes for profits; many plants were shut down, and some were dismantled. The number of operating plants declined from 454 on January 1, 1934, to 435 on January 1, 1935, but the number of inactive plants increased from 137 to a new high of 196 during the same period. As indicated above, new construction was at a minimum in 1934, and on January 1, 1935, only 7 plants were being built.

Jan 1, 1935

By M. J. Farrell

Mining is a significant emitter of greenhouse gases and is the focus of increasing attention from green groups and regulators. Miners need to know their own carbon emissions and how they compare with the rest of the industry. Miners and mining companies need to know where they fit in the emissions curve. Who is in the bottom quartile? This article updates data from minecost.com which detail the specific carbon dioxide emissions for over 200 mines producing 90% or more of western world copper, zinc, lead and nickel in 2009. This data shows the potential impact on mine economics of proposed carbon taxation regimes and emissions trading schemes proposed at COP 15 in Copenhagen during December.

Jan 1, 2010

By Raymond A. Binns

The Eastern Manus Basin (EMB) contains three major active hydrothermal zones and a number of smaller occurrences of hydrothermal deposits, and can be considered as a regional-scale modern analogue for volcanic-hosted mineral fields on land. Unlike the central Manus Basin, a back-arc spreading zone with some MORB-like basalt-hosted massive sulfide deposits, the EMB is a pull-apart rift zone between two transform faults, where a basement of Eocene-Oligocene arc crust is being thinned by extension, with rapid sedimentation on the tilted fault blocks. Present-day submarine igneous activity in the EMB, with which hydrothermal activity is associated, has arc geochemical affinities and is related to subduction of the Solomon Sea Plate at the New Britain Trench. Overall, hydrothermal deposits in EMB are found with lavas ranging from picritic basalt to rhyodacite in composition, although the two major occurrences of massive sulfide are hosted by the more siliceous dacite and rhyodacite variants. Some volcanic edifices are central eruptions, mostly of porphyritic lavas or domes, while others are elongate ridges formed by fissure eruption in which the typically aphyric lavas were very fluid. Evidence for shallow-level fractional crystallisation controls of lava chemistry implies presence of subjacent differentiated intrusions or former magma chambers. Seismic tremor at one site during the nearby 1994 Rabaul eruption suggests magma movement in the chamber.

Jan 1, 1998

By G. W. Jones, R. E. Kennedy

"INTRODUCTION In the manufacture, storage, transportation, and use of combustible gases and vapors, explosion hazards, which at times may be present when air becomes mixed with the gases and vapors, become of primary importance. Such conditions are especially dangerous where large volumes of gaseous atmosphere are involved, because an explosion under such circumstances is capable of doing tremendous damage to both property and personnel.Because of its interest in safety in the mining and allied industries, the Federal Bureau of Mines has investigated, and published results dealing with, the explosibility of various types of combutible atmospheres. The explosion hazards of natural gases have received attention, and results giving the limits of inflammability and ignition temperatures in air have been determined and published. 4/ Other investigations have shown how explosions of natural gas-air mixtures may be prevented by the addition of nitrogen and carbon dioxide. 5/Because of the increased demand for crude oil for war purposes, the application of secondary-recovery methods of stimulating oil production have received considerable attention during the last few years. The process consists in the injection of natural gas into partly depleted oil wells to cause the oil in the sands to flow into producing wells and so increase the amount of recoverable oil. 6/"

Feb 1, 1945

By WILLARD W. CUTLER

This bulletin reviews, in the light of recent experience, the use of production-decline curves in estimating the future production of oil from wells. It deals with the estimation of the reserves of recoverable oil in properties already producing or in those adjacent to them, takes cognizance of the physical laws governing expulsion of oil from oil sands, and shows how the production-decline curve can be made to utilize these laws in estimating reserves and rates of production. The valuation of oil properties should be based on the total amount of oil recoverable from a property by the methods in use, the rate of recovery, the cost of production, and the selling price. Numerous other curves besides those for reserves and rates of production may be formed from the production-decline curve and will present desired information in a convenient time-saving form. These curves also are described. Methods developed before the production-decline curve method was used are briefly discussed in order that the principles on which estimations of oil reserves are based may be made plain. The construction of curves and tables for estimating future production of individual wells and of average wells in most of the important oil districts of the United States is described and operating problems that may be solved by the use of production-decline curves are discussed. The bulletin does not deal with costs, oil prices, or the methods of evaluating oil properties. Many engineers have amply demonstrated the value of the production- decline curve method by forecasting within reasonable limits the production of many thousands of wells and tracts. The value of similar estimates depends however, on (1) the application of trustworthy methods; (2) the care and judgment of the estimator; and (3) the length and reliability of the records and the accuracy of ofher information used in estimating future production. When adequate records and information are available, experience has shown that It qualified engineer can forecast production far more accurately than has been deemed possible, except where the usual conditions governing the expulsion of oil from a sand have been radically changed by applying compressed air or by flooding with water, or, to a less degree, by using vacuum. In general, the production-decline curve method, though there are limits to its accuracy, is far more trustworthy than any other.

Jan 1, 1924

By Richard G. Stearns

Extensive thick lignite apparently lies within 250 feet of the land surface in Dyer, Lake, Lauderdale, Obion and Tipton counties. Information on geology, land use, soils, groundwater and instability is compiled, along with a bibliography. A test and monitoring site was investigated at Fort Pillow Prison in Lauderdale County. Analyses were made of lignite, overburden, associated water and leachate. Lignite has high BTU (about 7800) and low sulfur (1.1% avg.). A year or more of data are presented on rainfall, water levels, and chemistry of surface water, groundwater, leachate and water from test pits. Main potential environmental problems are quality of surface water, and possibly shallow groundwater. The main aquifer of the region will likely be un-affected by mining. Low transmissibility of shallow aquifers will minimize lowering water levels of wells. Soil reclamation and conservation should be readily accomplished, Dangerous earthquakes have a low probability and mines are not significantly more hazardous than steep bluffs.

Jan 1, 1981

By Walter R. Storms

"The New Mexico potash exploration described herein was begun in February- 1944 by the Federal Bureau of Mines with the object of determining the amount of potash ore in the United States Potash Reserve in Eddy County, N. Mex., by exploring the deposit from the surface with vertical drill holes. The work was completed in October of the same year after 16 holes had been drilled on the reserve and in the immediate vicinity.The Potash Reserve is located in secs. 26, 27, 34, and 35, T. 20 S., R. 29 E., Eddy County, N. Mex., about 14 miles northeast of the city of Carlsbad. Drilling was done in secs. 26 and 35 of the reserve, in sec. 14 to the north, and secs. 25 and 36 to the east. All work was done on Government-owned, unleased land.The reserve may be reached from Carlsbad by traveling northeast by automobile for about 14 miles on paved U. S. Highway 62. This highway passes through the southern part of the reserve. Other parts may be reached by a State highway which passes along the eastern side of the area, then by poor dirt roads to various drilling sites. A branch of the Atchison, Topeka and Santa Fe Railroad also passes across the southern part of the reserve en route from Carlsbad to the plant and mine of the Potash Co. of America, a few miles northeast of the Project and 22 miles from Carlsbad.Work on the project was greatly facilitated by the help of Ralph H. King, associate geologist, R. K. Bailey, geochemist, H. C. Spicer, geophysicist, Hope Bunker, junior geologist, and R. H Allport, district mining supervisor, all of the Federal Geological Survey; and Charles H. Johnson, who at that time was district engineer for New Mexico for the Mining Branch of the Bureau of Mines."

Apr 1, 1946

By S. S. Venkata

This volume describes a comprehensive program of research into the reliability of mine electrical power system components and the resultant reliability of the total system. The research effort encompassed analytical models, laboratory testing and field testing. The analytical work included definition of terms, fail rate functions and distributions, failure rate estimation and techniques and procedures for theoretical reliability assessment. One of the primary mine power system components addressed in the study was the ac molded case circuit breaker. This device is known to have low reliability and hence an unfavorable impact on mine safety and productivity. Ac molded case circuit breaker reliability was studied by analytical means, laboratory testing and field monitoring. A similar three-pronged' effort was made to study the reliability of undervoltage relays/releases. Particular emphasis was placed on new solid state undervoltage relays. The reliability of bulk power components, such as trailing cab les, motors, control gear, and other equipment, was assessed by gathering maintenance records from active mines. These data were compared to similar records from other industries. The work was extended to include the reliability, availability, maintainability and safety of these components.

Jan 1, 1979

By Z. T. Bieniawski

Geomechanics signifies the science and engineering of soil and rock materials and of rock masses. It is a field of professional practice and research that draws heavily on the elements of soil and rock mechanics. Geomechanics contributes to a number of disciplines: mining engineering, civil engineering, geological engineering, petroleum and natural gas engineering, and engineering geology (including the elements of geohydrology and geophysics). These disciplines are involved in the design and construction of such projects as mines, tunnels, foundations for structures, excavated rock slopes, dams, shafts, boreholes, oil reservoir wells, underground storage facilities for oil and gas, and hazardous waste repositories. Geomechanics allows us to improve both our environment and our quality of life. In the context of this Handbook, the scope of geomechanics is discussed mainly from the point of view of applications to mining engineering. However, the coverage of the subject mate¬rial is so comprehensive that it is relevant to other disciplines as well. Section 10 covers the field of geomechanics in a structured fashion, beginning with the fundamental principles and leading into practical applications in mining engineering. Throughout the treatment of the subject, knowledge of geologic conditions is assumed since this is discussed in other sections of the Handbook. An important feature of this section is a series of practical examples illustrating the various aspects of geomechanics. Since geomechanics is concerned with both soil and rock mechanics, Chapter 10.1 introduces the fundamentals of soil

Jan 1, 2008

By C. Meyer, J. J. Eidel

C. W. Hunt I wish to register strong disagreement with the choices of drilling sites chosen by the Continental Scientific Drilling Committee, while endorsing the stated objectives. Of special significance is the lack of any site involving the metals most needed today in the US, while 9 to 13 km of drilling are allocated to gold and silver districts and 11 to 17 km to base metal (mainly copper) districts. Why is nothing proposed for platinum group or chromite? Is this because the committee did not know of such a site? If so, I offer such a site in California (see Fig. 1). The mineralization shown in Table 1 occurs in a large peridotite body in western Tehama County, CA. Petrography has demonstrated unequivocal evidence of migrated PGE deposited in peridotite and chromite of hypabyssal nature. Active diapirism (due probably to serpentine buoyancy) above a reactivated mantle to surface conduit marks the position of the conduit. Young explosion breccia cemented loosely by volcanic glass and tuff demonstrates the significance of the conduit as the prime source of the various emissions. Deep drilling could result in major metals discoveries as well as shedding light on the grand questions of platinum group mineralization. What role water has played in this occurrence is not yet certain; but chlorine and asphaltite have been detected in and adjacent to native PGM, suggesting a major role for water. The explosion breccia suggests that this excellent site could overlie entrapped geothermal steam.

Jan 6, 1987

By Jim F. Lemons

INTRODUCTION A nickel doesn't buy much anymore. That's even true in the cost of recovering nickel -- the commodity. A 5[C] per pound (11 [c] per kilogram) increase in the nickel price won't cover a 10-percent increase in fuel costs for processing laterite ores, nor will it cover a 10- percent increase in wages for recovering nickel from a sulphide ore. It won't even cover a 5- percent increase in the capital cost necessary to mine and process ocean nodules. The basis for this statement and a quantitative analysis of the variations in costs to recover nickel from different types of nickel ores will be discussed in this paper. During the early part of the 1970's, the interest in nickel and its potential development was shifting from Canada to the Pacific Basin area. Canadian growth rate was slowing and each additional increase in nickel capacity was very expensive (Argall, G.O., 1970). Laterite ores were attractive to developers since they were easy to mine at a low labor cost, and technologies were being developed that would allow the recovery of nickel in marketable forms (Mohide, T.P., Warden, C.L., Mason, J.D., 1977). During the last decade, new laterite production was achieved in the Philippines and Botswana, and a significant increase in production from Indonesia and New Caledonia occurred. However, recent reports on nickel identify numerous problems plaguing the industry, i.e., high energy costs that are forcing shutdowns (INCO, 1980), (Mohide, T.P., Warden, C.L., Mason, J.D., 1977), high Canadian sulphide mining labor costs (Anon., 1976), and rapid inflation of nickel capital costs (Anon., 1981b). No definitive study has been made to determine how sensitive the total cost of production is to rising energy, labor, or capital costs, or to identify to what extent increased byproduct revenues could be used to offset these production costs. The purpose of this paper is to quantify the effects of increases in energy, labor, capital costs, and by-product credits on the future cost of production from nickel reserves and/or resources. METHODOLOGY OF ANALYSIS In order to evaluate the sensitivity of nickel production costs to changes in energy, labor, and capital costs, and in byproduct revenues, an analysis was made of existing and proposed nickel operations, their costs, and their sensitivity to change. The data for these analyses were obtained from numerous sources including international govern¬ment and university publications, professional journals, company reports, private communications, U.S. Bureau of Mines contracts, and estimates by Bureau of Mines personnel. These data were collected, in part, as an ongoing effort of the U.S. Bureau of Mines Minerals Availability System (MAS) to systematically measure and classify identified mineral resources according to their respective extraction technologies, economics, and commercial availability. The MAS Program is currently evaluating the present and potential availability of nickel to the United States in relation to mining, beneficiation, smelting, refining, leaching, transportation, infrastructure, environment, land use, labor, productivity, technology efficiencies, operating capacities, deposit life, and political factors. As a summary of this data, the following briefly describes nickel ore types as each relates to energy, labor, capital, and byproducts. Sulphide Operations Nickel is currently available from sulphide deposits. Roughly 55 percent of the current world nickel production in market economy countries is from sulphide ores, although only about 20 percent of the known land-based nickel reserves and/or resources are sulphides (INCO, 1981). In 1979, the Western World sulphide reserves were estimated at about 9.2 million metric tons of nickel (Little, A.D., 1979). Sulphide ores are typically mined underground, thus resulting in high mining costs; however, these ores can often be upgraded by flotation prior to final nickel recovery and require about one-third of the energy required to recover nickel from laterites (Anon., 1981c). In addition, nickel in sulphide ores may be associated with economically recoverable byproducts, which include copper, cobalt, gold, silver, and other precious metals. Laterite Operations Forty-five percent of current nickel production is from laterite deposits. Laterite deposits account for 80 percent of the known land-based nickel reserves and/or resources (INCO, 1981). In 1979, the Western World laterite reserves were estimated at over 35 million metric tons of nickel (Little, A.D., 1979). Nickeliferrous laterites are residual soils formed by weathering, typically under tropical or near tropical conditions. They can be easily mined by open-cut methods, but generally cannot be beneficiated; thus, recovery of nickel must entail processing of the total mined ore. Usually, these ores have high moisture content (20 to 30 percent by weight) that result in additional fuel costs to dry the ore. Nickel silicates, garnierites, are, processed by pyrometallurgical methods; limonite nickel oxides are normally leached. Byproduct cobalt is not recovered from most ferronickel operations, and is only recovered to a limited extent from many leach operations.

Jan 1, 1982