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By Randall J. Weege

Nickel laterites throughout the world are similar in their gross aspects, but vary significantly in detail. The deposits occur in two separate and distinct geologic settings --those formed over ultramafic rocks which were mechanically emplaced, and those formed over ultramafic rocks that were intruded as melts. The source of the primary nickel in the parent rock may occur both as ionic replacement in silicate lattices and as nickel sulfides. Factors controlling the degree of laterization and nickel enrichment are dependent upon the parent rock characteristics as well as chemical and climatic conditions. Two chemically and physically distinct zones (oxide and saprolite) are commonly present in the laterized rock, but one or the other may be extremely thin or absent. Cobalt and copper may be present in recoverable amounts. Geologic, geophysical and geochemical methods are all utilized in exploring for these deposits. These methods are compared, evaluated and illustrated in the paper. Drilling patterns and ore reserve calculations are also discussed. In contrast to many ore deposits, processing costs are much higher than mining costs. The most efficient processing method is directly dependent upon the chemical composition of the ore. This variation in the chemical and physical characteristics of nickel laterites requires a detailed test program of the metallurgical response to representative samples and blends of ore. Detailed laboratory and bench-scale metallurgical tests are necessary prior to a full scale pilot plant test.

Jan 1, 1978

By Vernon PN

The Eossing Uranium Mine is a high tonnage low grade open pit operation using acid leaching for uranium extraction and ion exchange and solvent extraction for solution purification. Advanced technology, much of it computer based, has led to major economies that have contained operating unit costs over the last four years in the face of double figure inflation. An improved ore reserve block model and mine planning system have achieved a considerable reduction in the stripping ratio. Drilling and blasting costs have decreased some 25%, mainly by the introduction of heavy ANFO explosive. A centralised computer control centre for the metallurgical plant has increased labour productivity resulting in improved process control. The all-staff workforce is united with management in the objectives of creating a safe, healthy, working and living environment and a prosperous company, capable of contributing to the wellbeing of the nation and the shareholders. This situation has been brought into being by an equal opportunity policy coupled with a management system emphasising open two-way communication through all levels in the organisation. The success of this policy is highly apparent in the morale and productivity of the workforce.

Jan 1, 1986

By D. A. Dahlstrom

Crushing and grinding consumes about 1.3% of the nations produced electrical energy.( Furthermore, only one in the first ten highest consumers comes from an industry other than mineral processing. This is the grinding of wheat to make flour. The other nine are all in the metallurgical industry and are easily the largest consumers.

Jan 1, 1988

By L. A. Neumeier

Sound experimental ingots of zinc alloys for use as rolling slabs were cast with a specially constructed, semicontinuous casting machine. Nominal alloy compositions of Zn-1.0 percent Cu, Zn-0.12 and 0.36 percent Ti, and Zn-1.0 percent Cu-0.03 to 0.36 percent Ti were cast. This Bureau of Mines study was conducted to evaluate the suitability of the casting procedure for providing stock for rolling into sheet. Microscopic examination of ingot sections revealed structures in which grain size varied from the outer to center ingot zones. Columnar grains present in the center zone of the Zn-1.0 percent Cu ingot were absent in the titanium-containing ingots. The ingots with titanium displayed a finer grain size and eutectic structure in the center ingot zone than in the outer zone; the transition in grain size between the two zones was quite abrupt in some ingots. The overall grain size of the titanium-containing ingots was finer than that of alloys cast by more conventional methods. Chemical analysis revealed that compositional segregation is not a significant factor in the formation of the ingot structure. Microstructural studies of small ingots of similar alloys solidified at slow, fast, and intermediate rates confirmed that the ingot structure in the semicontinuous-cast ingots is related to cooling rate, which is, in turn, related to the particular casting machine design and the influx of cooling water on the withdrawing ingots. Microstructures of thin sheet hot-rolled from slabs of the semicontinuous-cast ingots demonstrated that the ingot structure does not preclude the rolling of sheet having a uniform microstructure. Results of hardness surveys of the semicontinuous-cast ingots demonstrated that copper and titanium exert essentially additive hardening effects in these cast alloys.

Jan 1, 1968

Iron deposits of every major type except laterite occur in Quebec, and form one of the major iron ore resources of the world. The five principal types of ore described are: (1) hematite-goethite masses derived from iron formation through the oxidation and enrichment of iron by natural processes; (2) taconites consisting of fine-grained iron formation; (3) metataconites composed of coarse-grained iron formation; (4) iron and titanium oxide minerals in massive or disseminateed deposits within gabbro and anorthositic rocks; and (5) replacement or contact? metasomatic magnetite deposits associated with complex silicate and skarn mineral assemblages. Most of the ore, although relatively low grade, is easy to concentrate. The physical properties of the ores that affect the choice and efficiency of beneficiation methods are described. The extent to which iron ore from this area can be utilized in the future will depend on the continued use and improvement of highly efficient methods of beneficiation.

Jan 1, 1964

By John Lovering

The Afton property is located 180 air miles East-Northeast of Vancouver and nine miles West of Kamloops, a city of 60,000 people, in South Central British Columbia, Canada. The mine is adjacent to the Trans-Canada Highway at an elevation of 2,200 feet above sea level. The orebody is a porphyry, copper deposit that has undergone supergene alteration. The-major economic minerals in the supergene zone are native copper and chalcocite with chalcopyrite and bornite in the hypergene areas. The grade is one percent with an overall copper distribution: 70% native, 25% chalcocite and 5% chalcopyrite with bornite and covellite. The ore also contains important, but variable amounts of gold and silver.

Jan 1, 1985

By H. C. Gunning

Introduction Considerable attention has of late been attracted to the area surrounding Nimpkish lake, on northern Vancouver island, by the discovery of important rich copper deposits. In less than two years some 200 mineral claims have been staked in a small area, and at least two groups have very promising surface showings. During the summer of 1929, the writer spent one month investigating the general geology and mineral deposits of the region, and, although no detailed work has as yet been done in the field or in the laboratory, the importance of the mineral discoveries and the lack of geological information available to the public warrants a preliminary paper on the district. The district is, from a mining viewpoint, very accessible. Boats from Vancouver call at Englewood, in Beaver cove, four times a week. From Englewood, a first-class logging railway, operated by the Wood, .English Company, extends to the northeast corner of Nimpkish lake. The fifteen-mile trip from the north to the south end of the lake is made by boat, two tugs being maintained by the logging company. The whole trip from Englewood can easily be made in one day. The known mineral deposits lie immediately east of the southern part of the lake, four miles or less from the shore. A fair trail, four miles ? long, leads from the lake to the Nimpkish Copper group. Apart from this trail and an old logging railway grade which follows the east side of Klaanch river for several miles, no trails exist on the southeast side of the lake.

Jan 1, 1930

By G. W. Evatt

This paper presents the scientific framework underpinning the Resource Valuation and Optimisation Model (RVOM). The RVOM is a Real Options software package, which helps mine owners optimally plan their operations, understand their project risks, and make defensible valuations. This is achieved in the presence of both financial and physical uncertainty. The three key outputs from the RVOM are: Valuation, Optimal Decision and Probability of Decision, where a decision can include any combination of: normal operation, expanded operation, care and maintenance, and abandonment (and variants thereof). This paper presents a clear example of the RVOMs usage to a case-study gold mine.

Jan 1, 2011

By Philip C. Tully

The Bureau of Mines, in a continuing effort to improve processes and methods of helium purification, has developed a differential distillation method for removing helium-3 from helium-4. Differential distillation at 4.2 to 1.6 K was used to reduce the helium-3 in helium-4 from about 200 to less than 1 part per billion. The results from four stills ranging in size from 1 to 25 liters are reported. The method has the potential to be adapted to commercial-scale separations.

Jan 1, 1975

By E. J. Schmitz

Coming from San Antonio, Texas, and following the Galveston, Harrisburg and San Antonio Railroad westwards, one enters soon the Cretaceous formation, which forms a belt of several hundred miles, extending westwards to the boundary of Arizona and across the Rio Grande into the State of Coahuila, Mexico. The members of this formation are very numerous and in petrographical character very diverse—from a whitish or bluish, slaty, impure limestone to a hard, beautiful blue-and-red striped, and a compact heavy-bedded,

Jan 1, 1885

By X. Shi

Magnesium, the lightest structural metal, has not yet been considered as a serious contestant for automotive use due to its weaknesses in corrosion. Electroless nickel-boron alloys are well known for their corrosion resistance and hardness. An electroless nickel-boron layer was successfully deposited first on the chemical conversion pre-treated AZ31 alloy and also on the Ni-P coating which was deposited on the conversion coating. The electroless bath contained nickel sulphate and dimethylamine borane (DMAB) as main salts and the samples were activated by a 5 g/L AgNO3 solution before the electroless plating process. The presence of the conversion coating between the nickel coating and the AZ31 substrate acted as a barrier and prevented corrosion of the alloy. The morphology of the nickel-boron layer was studied using SEM. The crystal structure and the composition were examined by EDS and the hardness was measured. The corrosion behaviour of the nickel-boron layer deposited on the conversion coating and on the Ni-P coating was studied using potentiodynamic polarization in a 0.5M NaC1 solution. A saturated standard calomel electrode was used as a reference electrode. The results show that the nickel-boron coatings had a significantly better corrosion resistance than the AZ31.

Jan 1, 2006

By W. W. Adams

The extent to which coal mines have installed various types of haulage systems and mining machines is a subject about which there is little definite information available in convenient form for the country as a whole . A few State mine inspectors include in their annual reports such information for their respective States , but uniform data for the United States have not until recently been compiled . Several years ago the Bureau of Mines compiled from one of the standard mining directories * a statement showing the kinds of machines and haulage used in coal mines . The first statement was prepared from the 1918 edition of the directory in which detailed descriptions of coal mines were given . The information presumably related to the calendar year 1917. Similar statements have been compiled from the directories for 1919 , 1920 , and 1922 , the statement for 1921 having been omitted because the directory for that year did not become available . The latest statement is given below and is based upon the directory for 1922. It relates to conditions prevailing in 1921 , and covers a total of 7,088 coal mines . Of these , 5,064 mines . or more than 71 per cent , were using animal haulage . As compared with the total number of all classes of mines , those in the animal - haul age group constituted 71.4 per cent , the percentage having remained practically stationary during the past four years , although the actual number of mines in the group has increased . Rope haulage was reported by 1,066 mines , or 15 per cent of the total , representing a larger number of mines than in 1918 , but a decrease of 2 in the percentage for the group as compared with all classes of mines . Electric haulage was reported by 3,274 mines (46.2 per cent ) , and the number of motors in use was 11,265 . The percentage of mines in this class has not changed materially, but the actual number of mines has shown a gain of about 900 during the past four years . Compressed-air locomotives have not increased either in actual or relative number , the percentage for the past year being but 1.2 . The number of mines using storage- battery locomotives has increased from 3.6 per cent of the total shown four years ago , to 9.8 per cent for last year, the latest figures showing 693 mines with 1,428

May 1, 1922

By Gérald Riverin, Bernard Boily, Daniel Bernard

"The Donalda gold deposit is located in the southern part of the Noranda camp, approximately 2 /em east of the Horne deposit. Combined past production and current reserves total over 1.5 Mt grading 6.9 grams of gold per tonne.The deposit consists of two main veins which are both narrow but persistent structures. The No 1 Vein, hosting about 80% of the gold ore, consists of an EW-striking banded quartz vein dipping on average 25° to the south. Although variable in thickness, it averages lessthan1 metre. TheNo2 Vein, located 300 m below the No 1 Vein, is similar to it except that it dips 50° south. Gold occurs mostly as fine native gold disseminated in quartz, with 2-3% pyrite and trace amounts of various sulphides and tellurides. The wall rocks are only weakly altered and mineralized with pyrite, hematite and sericite.Structurally, the Donalda deposit is centered on the Horne Creek fault (HCF) where the HCF is intersected by the ENE-trending DonaldaandCentralfaults.NorthoftheHCF,theNo1Veinishosted by the Quemont Rhyolite, whereas south of the HCF the vein is hosted by magnetic basalts and diorites of the Wilco Andesite Formation. The No 1 Vein extends across the HCF with only minor displacement, whereas the No 2 Vein has not yet been traced south of the HCF.A preliminary structural analysis of the mine shows that the HCF, which strikes 275° and dips 70° north in the mine area, has a reverse movement a lid that the flat dipping No 1 Vein is a tension vein. Both probably developed in response to the same stress conditions. Although the absolute age of the Donalda veins is not known, structural relationships indicate that they formed during the latest movements of the HCF, but prior to the intrusion of the Proterozoic D' Eldona Diabase. The occurrence along the HCF of gold-rich synvolcanic massive sulphides and much younger vein-type gold deposits (such as Donalda) indicates that the HCF was a very long-lived, deep-seated (?)structure which has controlled the circulation of gold-rich fluids over a long period of time."

Jan 1, 1990

By H Bruyn, K Ehrig, V Liebezeit, A Robertson, M Smith, D Grant

"The Olympic Dam geometallurgy program has generated a large quantity of data that has been used to create a geometallurgically enabled block model. An ongoing challenge is to convert data into usable information and embed geometallurgical practices into resource model development and mine planning to assist with the identification of opportunities to maximise value.This paper will discuss the methods used to disseminate geometallurgical information throughout the planning life cycle including data extraction methods from the geometallurgy acQuire database, and the inclusion of a geometallurgy module in the Olympic Dam Stope Reserves database. The use of geometallurgical information in short-, medium- and long-term mine design and scheduling, including its use in grade descriptor development and stope value assessment tools will also be presented. The detail of development of specific geometallurgical models is outside the scope of this paper.At Olympic Dam, the incorporation of geometallurgical capability within the long-term planning team, traditionally the domain of mining engineers, has proved essential in broadening the base of geometallurgical knowledge as well as focusing geometallurgy resources on value-adding areas while providing a holistic risk based long-term plan.CITATION:Liebezeit, V, Ehrig, K, Robertson, A, Grant, D, Smith, M and Bruyn, H, 2016. Embedding Geometallurgy into Mine Planning Practices – Practical Examples at Olympic Dam, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 135–144 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

There is mitigation for the sorrow of friends and the tragedy of sudden death when that death comes at the height of a successful career. It is not everyone's privilege to die, as has been the wish of many, in the harness—toiling, accomplishing, still necessary to the scheme of things. Nor is it everyone's privilege to leave a monument to his work. Dr. Fred Walter McNair died thus—in the midst of his work of educating, leaving along the path down the quarter century of his presidency of the Michigan College of Mines hundreds of men who, having come under his influence, have been successful in life.

Jan 1, 1924

By Jiann-Yang Hwang

The economic growth in new developing countries such as China and India has stimulated strong demands in basic materials such as steel. World steel production has exceeded the milestone of a billion tons a year recently. However, the blast furnace technology, which was invented in 1340 A.D., is still the fundamental route for today?s steel production. It is important to develop a new generation of steelmaking technology that can meet the society?s needs from the energy, environmental and economic standpoints in the 21st century. The new microwave and electric arc heating technology discussed in this paper provides a totally different mass and heat transfer mechanism from the conventional blast furnace technology and offers a great potential to meet our society?s needs.

Jan 1, 2006

Optimisation of mining projects is directly related to effective and efficient management of risks through the life cycle of mining projects. Effective and efficient management of risks must include explicitly all aspects of Occupational Health and Safety (OHS) through the life cycle of mining projects. This paper presents a different scale of OHS in the context of the optimisation of mining projects. Meaning of risk through the project life cycle is explained. Complex relationships between numerous risk, safety, knowledge, culture and change variables, and project life cycles are shown. The key element developed in this paper is a multi-disciplinary knowledge base that is necessary for constructive development of risk management and OHS models through the life cycle of mining projects.

Jan 1, 2003

By H. H. Vogel

THIS paper describes the milling practice and operating results of the recently installed heavy-media separation plant of Barton Mines Corporation, the world's largest producer of garnet. This pioneer application of heavy-media separation (sink-float) processes for the beneficiation of a nonmetallic ore is unique in many respects, the details of which will be apparent from the following presentation. CHARACTERISTICS OF THE ORE The property is on Gore Mountain, 5 miles west of the village of North Creek, New York, and 11 miles by road. The altitude of the mine is approximately 2800 feet. The valuable mineral, garnet, occurs in a surface deposit, the ore body being about ¾ mile long and varying in width from 50 to 300 ft. The garnet, principally almandite, Fe3A12 (Si04)3, occurs in a metamorphic rock of uncertain origin. The gangue mineral is principally hornblende, which constitutes from 40 to 80 per cent of the rock. The remainder of the gangue is divided between plagioclase feldspars and hypersthene, with smaller amounts of biotite, apatite and pyrite. The garnet content of the ore body varies from 5 to 20 per cent of the mass and averages about 10 to 12 per cent. The garnet occurs as crystals, mostly imperfectly developed, known locally as "pockets." These crystals vary in size from a fraction of an inch to a foot or more in diameter. Occasionally crystals have been found up to 30 and 36 in. in diameter but they average 4 to 6 inches. Nearly every crystal of garnet is surrounded by a rim of coarsely crystalline hornblende. The quarry faces are striking in appearance, showing crimson-red garnet crystals with their coal black rims scattered over a grayish black background. The specific gravity of the garnet is 3.8 to 4.1 while that of the hornblende ordinarily is 3.07 to 3.24. Some specimens of very dense hornblende have been found with a specific gravity as high as 3.40. The garnet crystals are laminated in structure, and readily cleave into flat, tabular pieces with sharp, chisel-like edges. Even when crushed to a very fine size, the garnet retains this flat, sharp, slivery grain shape. This characteristic, together with its hardness and toughness, gives it its value as an abrasive. FORMER OPERATIONS Mining operations have been carried on for 60 years. Until 1023, only the oxidized (soft rock) section of the ore body was mined. The oxidation, which affected the garnet only slightly, made possible the removal of the garnet from the rock by hand after it was blasted down, using small hand picks. In 1923 a mill was erected on the property, and was rebuilt and redesigned in 1928. Before the adoption of heavy-media separation, concentration was effected by

Jan 1, 1943

By M. Riddell

This paper describes the incipient heatings that occurred below ground in the High Main and Main seams at the mine between the years 1963 and 1966. The possible causes, effects and activities associated with such heatings are discussed in an attempt to establish the precautions necessary to minimize such occurrences. The assessment of as many "norms" as possible is made to enable the earliest detection and level of activity to be determined.

May 23, 1905

By Kubik K

Recent significant advances in the Global Positioning System (GPS) have contributed to making real-time kinematic/dynamic process for decimetre to centimetre-level positioning more reliable and ready for the production-use. As a result of research and development efforts in this area, a robust real-time kinematic (RTK) GPS positioning prototype system has been established at QUT for both scientific and engineering purposes. This system is finding applications in a wide range of automobile robots or automatic guidance vehicle systems. This paper first summarises the theoretical basis necessary for centimetre real-time kinematic positioning, then gives a brief description for the real-time dynamic GPS system developed at QUT. The paper summarises the results of a designed vehicle tracking test. The results demonstrated that the differences between RTK filtering solutions and OTF solutions are in the order of magnitude of about 20 centimetres and the accuracy of OTF solutions are in the levels of two centimetres. This confirms that the RTK system delivers three-dimensional position with decimetre-to-centimetre accuracy. This particular RTK processing system is robust and reliable, although the system is referred to as a prototype and will be further developed.

Jan 1, 1997