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By H. L. Paterson, R. R. Keays, M. J. Donaldson, D. J. Boyack, M. F. Smith, J. J. Gresham

"Albite-rich sedimentary rocks that contain abundant Fe sulphides occur in the lower portion of the ultramafic sequence at Kambalda and their broadly antipathetic relationship to most of the nickel orebodies is well documented. These sediments generally contain less than 0.1% Ni, but nickeliferous equivalents with 0.3 to >6% Ni occur locally in close spatial association with more typical volcanic peridotite-associated massive, matrix and disseminated ores. Nickeliferous sediments have been mined at several locations at Kambalda but, collectively, they constitute less than 2% of the total Kambalda nickel reserve. The nickeliferous sediments occur both on the ultramafic-footwall basalt contact and within the lower part of the ultramafic sequence, and are usually less than 5 m thick. They are commonly finely laminated rocks with a cherty appearance, composed essentially of layers of albite+quartz±amphibole, alternating with pyrrhotite+pentlandite±pyrite layers. Some contain a minor amount of carbon. The sediments are only of ore grade (> 1% Ni) immediately adjacent to massive Fe-Ni-Cu sulphides, which are interpreted as normal magmatic ores on the basis of geochemistry and the presence of distinctive ferrochromites. The nickel content of the sediments decreases to background levels (<0.1%) within about 20 m of the massive sulphides. In most locations the massive sulphides clearly have been emplaced tectonically within or adjacent to the sediments, which are commonly highly deformed. Typical nickeliferous sediments contain about 1% Ni, 0.1% Cu, 0.1% Zn, 400 ppb Pd, <0.2 ppb Ir and 10-200 ppb Au. They have lower Ni/Cu (average 10), higher S/Ni (average 6) and higher S/Se (average 11 200) than associated massive sulphides (average 40, 4.8 and 7400, respectively). The Pd/Ir ratio of the nickeliferous sediments (typically > 1000) contrasts markedly with that of associated massive sulphides (average ca 16).The high Pd/Ir values are similar to those which have been reported for hydrothermal Fe-Ni sulphides and barren sulphidic sediments of probable volcanic exhalative origin. They preclude a direct magmatic origin for the sulphides in the nickeliferous sediments, though S/Se and S isotope data indicate a magmatic source for the sulphur. The restriction of nickeliferous sediments to within about 20 m of normal magmatic sulphides and the lack of a widespread Ni dispersion halo suggest local redistribution of originally magmatic Ni. This probably occurred by diffusion and hydrothermal mobilization during deformation and amphibolite-facies metamorphism. Although not totally ruled out, a volcanic exhalative origin for the Ni seems unlikely."

Jan 1, 1984

Development on the North Kalgurli mine has established a major penetration of ore into calc schist. This is controlled by a system of east-dipping strike faults. Previously, most calc schist ore bodies were regarded as being confined to the quartz dolerite greenstonecak schist contact environment.INTRODUCTIONOne of the most interesting and economically important developments which has taken place in the Kalgoorlie Field over the past 20 years is the proved penetration of ore into calc schist on the North Kalgurli Mine. This is quite extensive, both laterally and in depth, and has occasioned some modification of geological thought in the search for additional ore sources.Ore has been mined in calc schist almost since the first major gold discoveries were made and the principal features of the various types of deposit are well covered in the literature of the field. However, occurrences in calc schist have not been characterised by the same degree of continuity or frequency as the innumerable lode formations in the more favourable quartz dolerite, and there has been a tendency to regard them as isolated and discontinuous ore bearing structures, occurring only under very special conditions.It is not intended to describe the whole range of calc schist ore occurrences but only major controlling structures, whose penetration therein has been definitely established and in which an appreciable amount of ore has been and is still being found. It is considered that similar structures may present a major objective for future exploratory work in other parts of the field.

Jan 1, 1964

"Since World War II, urban communities have expanded at an unprecedented rate. The industrial mineral industry supplies the sand, grave], limestone, crushed rock, cement, gyp-sum, etc. for urbanization. Most de-posits in use are close to or within communities. Pollution of water and air has become a matter of public concern. Waste disposal and the effects of noise and vibration are subjects of public debate. Need for the reclamation of land after operations such as strip mining is discussed in magazine articles and on TV pro-grams; i.e., the general public is educated in the unattractive features of mining.Legislation is on the books and being drafted to regulate mining operations and their side effects. To avoid over-regulation and restrictive legislation, it is necessary that the public be educated and legislators informed of problems peculiar to the mining industry. Our side of the story needs publicity."

Jan 1, 1968

By S. F. Mauser

This report describes the study of factors which affect medium voltage (661 - 1000 volts) trailing cable splices used in underground coal mines. Improvements in quality, dependability, and design of splice kits and shop splices are presented in the study results and recommended guidelines and regulations. Recommended research programs are included which describe approaches for development of the recommended guidelines and regulations for medium voltage trailing cable splices. The basis for the conclusions and recommendations presented in this report is included in three appendices which describe a survey, splice examination, and general requirements development prepared during the progress of this study.

Jan 1, 1977

By Ronald L. Wiegel

In a mineral processing plant there are a number of routine decisions which are based at least in part on the plant&apos;s metallurgical performance. Among these are those related to: 1) equipment functioning properly 2) suitable operating conditions 3) reagents achieving desired results 4} determining operating response to changes in ore 5) defining circuits offering potential for improvement A step beyond the routine, are the periodic management evaluations of operating supervision and technical assistance, which are based largely on profit -a direct function of are availability, metallurgical performance and operating costs. The "yardstick", excuse me -"meterstick", by which performance is best measured is the plant metallurgical balance, which tells not only what was produced but how it was produced. Since this metallurgical balance is directly related to both plant profits and individual rewards, it is only reasonable to make that "meterstick" as precise as humanly possible.

Jan 1, 1978

By Joo Hyun Park, Hyun-Sik Park

"Gold is one of the most valuable and precious metals. But, the extraction efficiency of gold from natural resources is very low and labor-intensive due to very low concentration of gold, i.e.,1–5 ppm, which means that gold extraction processes produce extensive amounts of tailings. The gold content in printed circuit boards (PCB) from waste mobile phones is about 100 to 400 ppm, which is enormously greater than the concentration found in natural ores. Consequently, processes for recycling waste PCB and gold mine tailings become of increasing importance to maintain a sustainable society. As processing these waste materials by pyrometallurgical methods has become more economically attractive, understanding the thermodynamic behavior of gold in smelting slags under oxidizing and reducing conditions has become increasingly important. Therefore, in this study, the effects of slag chemistry, oxygen potential and temperature on gold solubility in smelting slags are discussed. From the results presented, the predominant species of gold is strongly dependent on the basicity of slag. Furthermore, more basic slags showed higher solubility of gold at a given oxygen partial pressure, and more oxidizing atmospheres enhanced the dissolution of gold to the molten slag phase. As a consequence, careful control of the slag composition during pyro-processing of gold-containing waste materials is required to maximize gold recovery. INTRODUCTIONGold has good physicochemical properties. Thus, it plays an increasingly important role in industrial applications. For example, over 300 tons of gold are used annually in electronic components (Hageluken &Corti, 2010).However, 75% of all gold ever produced has been extracted since 1910 and gold reserves in the world are becoming rapidly depleted (Louis & Pluchery, 2012).The cost of gold production and its price in the market have increased rapidly during last 20 years as shown in Figure 1, and interest in the recycling of gold-containing materials has naturally increased.The wastes from electronic equipment (e-wastes) contain large amounts of precious metals compared to their own respective ores, and therefore such wastes may be considered as a secondary source of valuable metals. For instance, the concentration of gold in natural ore is commonly 0.5–15 g/ton-ore (0.5–15 ppm), while its concentration in electronic circuit boards is over 10 times higher, typically being about 150 ppm in expansion cards and over 10,000 ppm in central processing units(Barbieri et al., 2010).Also, gold mine tailings are discharged after the flotation process as slurry form then stored near the operating plants (approx. 100 ton per day in one Korean gold mine). Gold mine tailings contain gold at about 1–2 g/ton. This is the reason why Au-containing materials such as e-wastes and mining wastes are highly important sources of gold (Yamasue et al., 2009)."

Jan 1, 2017

By John V. Beall

During the last quarter of 1948, two new machines, which may revolutionize the coal mining industry, made their first public appearance within two months of each other. Both are designed to mine and load coal continuously. On Oct. 27, the "Colmol," invented by C. H. Snyder and A. E. Lamm, president and executive vice-president, respectively, of the Sunnyhill Coal Co., was demonstrated at the No. 8 mine of that Company at New Lexington, Ohio. The "Joy Continuous Miner," invented by H. F. Silver, president of the Silver Engineering Works, Denver, and developed and manufactured by the Joy Manufacturing Co., was demonstrated at the Mathies mine, near Finleyville, Pa., in the Pittsburgh coal seam.

Jan 1, 1949

By M. Gagné, F. E. Goodwin

The mining industry represents a significant investment in infrastructure of which steel plays a key role. Many structures in a mine are made of steel including shaft structures (buntons, station steelwork and headgear); stope structures (roof supports, pipe hangers); haulageway structures (ore transfer stations, electrical stubbies); and surface structures (plant buildings, tank supports, pipe gantries, conveyor belts, stacks, stockpile structures, stairways and railings). Maintenance of structural components can often be difficult because of the environment, including those where corrosive fumes persist, or limited access, such as in shafts where access is limited, or to short maintenance shifts or where limited working space is available. Thus a cost-efficient, long-lasting and maintenance-free protection system for steel should be specified. Galvanizing provides the required high-quality, long-term corrosion protection to steel. Galvanizing provides protection in two ways, first as a physical barrier to corrosion and secondly by means of cathodic or sacrificial protection that is unique to zinc. The dual nature of corrosion protection provided by galvanizing significantly extends the service life of steel even in the most challenging environments. The unique corrosion protection properties provided by galvanized steel will be highlighted with global mining application case studies.

Jan 1, 2015

By K. Oraee

Zarshuran gold deposit, with the total reserves of some 12.5 million tons of 4.18 g/ton ore, is considered to be an important gold mining project in the area. In this paper the feasibility studies of the whole project is carried out on the basis of several economic variables. Given that mining data are often of uncertain nature, these economic variables have therefore been estimated under the conditions of uncertainty. The resultant Net Present Value is hence also obtained under the same conditions. For this purpose, a model is first devised with the help of Excel and COMFAR software. The model is then developed that considers different scenarios which would result in different expected values for the economic variables. It is concluded that the NPV of the project is most sensitive to gold and silver price and that other variables such as discount rate, operating and capital cost all affect the feasibility of the project with lower degree of severity. Finally, risk analysis is also carried out using Mont Carlo technique, in order to estimate the most probable value of NPV. The average NPV calculated in this way is US$ 49.7 Million, whilst without due consideration of risk, this would be US$ 36.6 Million. The techniques used, together with the procedures adopted in this paper, can be used in feasibility studies of all mining projects. Such decision would result in more accurate Net Present Values than expected from other frequently used methods.

Jan 1, 2011

By Charles B. Escapule

The first successful heap leach of silver ores in the State of Arizona has been under continuous operation since early 1976 at the State of Maine Mine, two miles southwest of Tombstone, Arizona. The silver produced from leaching old mine dumps at this property vas the first in the Tombstone mining district to achieve a 999+ purity. While cyanide leaching of silver and gold ores is a time-proven accepted practice, a relatively new method of treatment called "heap" leaching was employed. Heap leaching is a comparatively inexpensive fast way to recover precious metals from low grade material.

Jan 1, 1981

By Peter F. Mataich

The phosphate mining industry is a highly competitive one, one in which survival depends on the plant&apos;s ability to produce at costs equal to, or below, the competition. The solution toward getting costs down is usually one of scaling up the plants to get the most tons through at the lowest possible cost. Control of these plants has been an art. Few of them are well instrumented because until a few years ago reliable instrumentation was non-existent. International Minerals and Chemical Corporation was a pioneer in applying computer techniques to ore reserves analysis and mine planning and the success in these areas led to the question of whether we could not extend the advantages of computer processing into the plant itself. There was a great deal of doubt on the operator&apos;s end that this could be done successfully because of the lack of instrumentation and the fact that plant control was largely an art that was learned only after many years of experience. However, in 1965 the instrumentation picture began to look up and the new generation of process computers just coming on the market were considerably lower in cost than the previous ones. A preliminary study of the installation costs and the probable benefits that could be realized from computer control convinced us that a process control computer should be seriously considered for a new phosphate mining plant which was being designed.

Jan 1, 1969

By A. Yazadni-Chamzini

Risk ranking of projects is one of the importance parts of the complicated risk management procedure. Recognizing the riskiest criteria enable the managers to plan for risk reduction. The first stage for meeting this aim is defining the risky parameters and then working to establish order between them. There are variety methods for risk ranking. The ELECTRE method is one of the best among the multi criteria decision making methods. In this paper with implementing the fuzzy ELECTRE, The risky criteria in the Tehran Subway project are being ranked. The result of this research presents damage and accident of machineries as well as the lack of labor and equipment safety is located in the first order. Collapse factors and local prices are in second rank. Also wrong design, pollution, urban facilities damageable are in third to fifth respectively. Delay and ? are located in the last positions.

Jan 1, 2012

By McHenry Mosier

This progress report on a national survey of the use of detachable bits in metal mines covers 10 mines. It presents comparative costs for drilling with conventional and detachable bits, describes the reconditioning of drill steel, and gives various data on rock drilling at these particular mines. Reports to follow will include similar data on drilling at other metal mines in the United States. ACKNOWLEDGMENTS This report is based on costs and data developed and furnished by the operators of the mines visited. The author is greatly indebted to the officials and staff members at these mines for their cooperation and assistance.

Jan 1, 1936

By Phillip A. Armstrong, Charles A. Lewinsohn, John H. Gordon

"This paper describes the opportunity offered by employing systems based on mixed conductive ceramics, in particular, ceramics conductive to oxygen ions and electrons, in reducing CO2 emissions from metallurgical production. Membranes based on these mixed conducting properties enable commercial viability of several attractive metallurgical processes. One of these processes utilizes modular, ceramic-membrane structures for the generation of pure oxygen, in tonnage quantity. The membrane-based systems offer significant capital savings and operating efficiencies in various metallurgical processes. The current status of this technology is summarized below.IntroductionCryogenic oxygen supply technology is currently the state-of-the-art for applications that require large quantities of oxygen (hundreds to thousands of tons per day). Cryogenic technology, however, requires substantial energy inputs and, hence, adds significant costs and emissions to processes. Furthermore, cryogenic oxygen supply technology is mature and there is relatively little potential for substantial capital cost reduction or efficiency improvement in coming decades. Non-cryogenic technologies offer a means to reduce the environmental footprint and cost of the oxygen supply facility in various applications.Ion Transport membranesCommercially available non-cryogenic air separation technologies, such as adsorption-based and polymeric membrane-based methods, do not afford the economies of scale that the cryogenic distillation enjoys. Therefore, industrial gas industry researchers began searching for alternatives to the relatively inactive and unselective polymeric membrane materials available. In the late 1980’s, Air Products began developing a new class of highly selective membrane materials with exceptionally high activity for oxygen transport. The materials constitute a class of oxide ceramics, and conduct both oxygen (as oxygen ions) and electrons in the same membrane, separating oxygen from air electrochemically. Numerous detailed process economics studies have shown that, based on these ion-transport membranes (ITM’s), the cost of oxygen can be reduced by approximately one-third relative to that obtained from state-of-the-art cryogenic oxygen supply technology, through a combination of capital cost savings and efficiency improvements. [1,2,3]"

Jan 1, 2008

By Bill Shand

"Placer Dome - Campbell Mine is a gold mine located at Balmertown in the Red Lake District of North Western Ontario. During the last 50 years, the mine has produced over ten million ounces of gold.A change in ball mill grinding media was made in August 1998 from 1.5” diameter forged balls to 1.5” diameter, 18% chrome balls. This was done to reduce grinding media consumption and to potentially help flotation performance.A marked ball test done in September-October 1999 showed that, of the alloys tested, 18% chrome was the optimum for the ore at Campbell Mine. The test showed that consumption of chrome balls should be 3 times less than forged balls.In December 1999, the ball size was increased from 1.5” to 2” in an effort to reduce the amount of oversize rock discharging from the ball mill. This change in size was successful.Grinding media consumption for the ball mill decreased 73% from 1.20 kg/tonne before the use of chrome balls to 0.327 kg/tonne after the use of chrome balls. This clearly indicates that, for the ore at Campbell Mine, there is significant savings in grinding media by using chrome.Grinding ball costs were reduced by 59% from $O.88/tonne of ore milled to $0.36/tonne of ore milled representing a saving of $298,000 per year. This also clearly indicates that using chrome balls is a benefit at Campbell Mine.Test work to show that chrome grinding media is beneficial to flotation has been inconclusive so far but is still ongoing.No tests have been done to see if there would be a benefit with an even higher chrome percentage in the grinding media. Test work in this area is also planned for the future"

Jan 1, 2001

By H. K. Taylor, B. Denby, L. D. Smith

Contributions by H.K. Taylor and G.A. Davis discuss the three papers published in Transactions IMM A, vols. 103 and 104, with responses by Smith and Dowd

Dec 1, 1995

By Clamer, G. H.

G. H. CLAMER, * PHILADELPHIA, PA.-Unfortunately, prior to the war no serious attention was given to the conservation of tin, notwithstanding that this country is practically dependent upon outside sources for its entire tin supply. Tin is of vital importance in many industries, but it is surprising how many and how excellent are its substitutes when we become acquainted with them. Tin has always been a relatively high-priced metal, and it is part of the human attitude to associate high prices with high standards; it is not until the price of a commodity becomes well-nigh prohibitive that we hunt for substitutes, because the idea of substitution seems always to involve an assumption that the substitute must necessarily be inferior. The history of the development of bearing bronzes is a striking example of this policy. In the early clays, copper-tin alloys were almost universally used, the idea then being prevalent, which is still held by many, that a bearing to resist wear must be hard, and the harder the better. The favorite bronze bearing contained 90 per cent. copper and 10 per cent. tin; frequently, in service which was considered severe, even higher proportions of tin were used.. Such hard alloys have great resistance to compression, but as a rule they had a very wide factor of safety in this

Jan 12, 1918

By M Fitzgerald

Fimiston Open Pit is operated by Kalgoorlie Consolidated Gold Mines (KCGM) as a joint venture between Barrick Gold and Newmont Mining. Over 110 years of underground mining resulted in the development of nearly 3500 km of underground workings including backfilled and open stopes up to half a million tonnes in size. These voids significantly complicate blasting processes at KCGM, influencing blast movement direction and magnitude. Blast movement monitoring to improve mine reconciliations was identified as an improvement project in the business plan for the geology team in 2008. Following successful trials in 2008 to 2009, blast monitoring and translation of ore blocks were implemented as a permanent grade control program from late 2009 and is now part of the Management Operating System (MOS) of the mine. This paper presents a summary of results from the Blast Movement Monitoring (BMM&#174;) data collected to date. Ore blocks at KCGM are translated primarily using BMM&#174; data. This data is obtained from the BMM&#174; system which measures the movement of a radio transmitter installed in a blast pattern from a preblast position to a post-blast position. The application of the data collected by the BMM&#174; tends to be both mine site and blast specific. At KCGM, an average distance obtained from the BMM&#174; data within a given shot is the primary method used for translation. In the case that BMM&#174; data is unavailable, a theoretical movement vector established from Orica Shotplus with distances gained from the historical BMM&#174; database is used. Data is presented in an ore loss and dilution exercise for a bench undertaken at KCGM to understand the potential effects on reconciliations. Improvements that have flowed from implementing blast monitoring include improved reconciliations when combined with other grade control improvement projects. The increase in liaison between the geology and blast personnel at KCGM has been a significant improvement gained from the implementation of the blast monitoring program. This has allowed a better understanding of blast movement and the effects on ore dilution and ore loss by the mine geology team. In addition, the discussion of blasting tie-in plans between geology and blasting personnel has been improved which leads to more favourable blasting practices that take ore movement into account.

Aug 22, 2011

Semisoluble salt minerals are characterized by their ionic bonding and are distinguished from soluble salt minerals by their limited solubility in water. One group of semisoluble salt minerals being considered is the alkaline earth salt minerals, including fluorite (CaF2), calcite (CaCO3) and apatite (Ca5F (PO4)3), as well as celestite (SrSO4) and barite (BaSO4). Another group of semisoluble salt minerals being considered is the rare-earth salts, which include bastnaesite ((Ce, La) CO3F), monazite (CePO4) and xenotime (YPO4). Surface chemistry features of these selected semisoluble salt minerals are discussed with respect to flotation separations. First, the surface chemistry features of alkaline earth semisoluble salt minerals are reviewed, and then the surface chemistry features of rare-earth semisoluble salt minerals are examined. The discussion includes electrokinetic behavior, wetting characteristics and collector adsorption.

By H. F. Yancey

This report, dealing with the separation of coal from its associated impurities by means of a pulsater-type jig, continues the series of reports that have been issued by the Bureau of Mines, in which detailed study has been made of the efficiency and mechanism of separating coal and impurities in various coal-cleaning appliances. The previous reports have dealt with the piston jig, coal-washing table, pneumatic table, and Baum-type jig. Such studies of the separation accomplished by any form of concentration device are essential and necessarily preliminary to any intelligent attempt to improve the performance of such equipment Object and Plan The pulsator-type jig was developed recently by G. A. Vissac. Although two articles(2) describing plants using this typo of cleaning unit appeared in 1936, both dealt principally with plant design and layout rather than with plant performance The object of the stork described in this report was to determine the efficiency of the separation made by the pulsator jig on a sized feed, the specific gravity at which the separation between coal and impurity was effected, and the influence of the specific-gravity composition of the coal on the character of the separation made.

Jan 1, 1938