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By Babbitts and Solder

G. w. Thompson,* Brooklyn, N. Y.—This subject has two aspects, neither of which can be ignored: these are the economic aspect and the technical aspect. Under ordinary conditions, economic law will take care of the conservation of tin. Under present conditions it seems desirable that economic law should still be permitted to operate as far as is practicable. It is true that this law operates rather slowly, and that under war conditions it cannot be depended upon to give our Government the supply it immediately needs. There should, therefore, be a designation of the essential industries by the Government, and tin should be supplied for those needs, letting the non-essential industries take what is left. At the same time, information ought to be forthcoming as to how tin can be conserved; with tin selling at 80 c. per pound, more or less, it is to the interest of every consumer to get the best information he can as to how he can save tin. Economic law would properly punish those who do not study their own interests in this way. I deprecate, therefore, any centralized socialistic effort toward avoiding penalties through failure to observe and obey economic law. In saying this, however, I am not unmindful that it is desirable for our Government to take such control of the tin situation as may be necessary to the prosecution of the war, practically regardless of the effect of such action upon individual industry, which should studiously seek to adjust itself to the new condition. The Government should promulgate such technical information as it can collect, showing how .tin can be conserved, and should urge upon every consumer the exercise of his common sense in self-protection. There is very little danger of any one attempting to hoard or corner tin, in the present state of the market. Most consumers will be glad to live from hand to mouth, covering their sales by purchases, or vice versa. As to the technical aspects: Tin and tin alloys are used to give certain practical and also certain artistic results. The practical factors are those involved in proper adhesion, continuity of surface, protection, the right degree of hardness, proper working qualities, etc. The artistic results are those that appeal purely to the eye or to our cultivated sense of what is desirable. There is no doubt that a great deal of tin could be saved if there were not a demand for certain pleasing effects. Row can this saving be brought about? The users of tin bearing alloys are not the only ones involved in this question. The manufacturers of solder and babbitt have for a long time sought to give certain appearances to their fabricated bars and ingots in order to make them more salable. The user of a solder is very apt to judge of its working qualities by the appearance of the bar; the same thing is true with regard to babbitts. Under ordinary conditions, manufacturers are justified in trying to

Jan 1, 1919

By Luís Tavares Ribeiro

Nowadays there is a greater need for detailed reservoir modelling in the oil industry. It is generally recognized that nearly all reservoirs are heterogeneous and idealization of rock characteristics in flow calculations is unrealistic regarding actual physical and textural conditions encountered in geologic formations. The heterogeneity of oil reservoirs considerably influences the distribution of fluids, as well as their displacement. It would be advantageous if a reservoir petroleum engineer was able to construct a precise mathematical model of the detailed reservoir rock variability characterizing the degree of reservoir heterogeneity in an unambiguous way. This paper presents a geomathematical model describing the spatial behaviour and distribution of the principal reservoir properties. The model is based on the Theory of Regionalised Variables and the Kriging technique. The model is performed by a set of computing programs and is tested on an Abu Dhabi oil reservoir in United Arab Emirates.

Jan 1, 1986

By J. W. C. Wong, S. D. Miller, J. J. Jeffery

Pre-mining identification of acid forming mine and waste materials is of concern to the mining industry because of the potential for the generation of acid mine drainage, acid rock drainage, and soil acidity problems. Accurate identification of acid forming material is essential for developing appropriate waste management strategies to reduce environmental problems related to acid generation from sulphide containing wastes. The acid-base accounting procedure, in its various forms , is commonly used for pre-mining screening of mine and mine waste materials. The procedure is generally effective when used and applied correctly but is prone to incorrect interpretation of results which can have significant financial and environmental implications. This paper examines the acid-base accounting Procedure and the possibility of misuse of this method with special emphasis on the sampling method, the sulphide forms, the acid neutralization capacity, and the interpretation of results. Data from numerous coal, base metal, and gold mining operations are used to illustrate the application of the acid-base account. The data base indicates that overall, approximately 1/3 of all waste generated by mining and mineral processing is potentially acid forming indicating the need for correct identification and management. Problems associated with simple application of 'absolute' acid-base criteria for classifying acid forming material are highlighted and the need for developing site specific or 'relative' criteria is discussed and illustrated by case study.

Jan 1, 1991

By Stephen Birch

THE Chitina mining district of Alaska is located at the headwaters of the Chitina and Copper Rivers. At present, the only producing min-ing properties are the mines of the Kennecott Copper Corpn. and the Mother Lode Coalition Co., which are situated 196 miles from Cordova the port of entry. The first claims, later acquired by the Kennecott Mines Co. and afterwards transferred to the Kennecott Copper Corpn., were discovered in 1900. The Copper River & Northwestern Ry., which connects the mines with tide water at Cordova, was completed in the spring of 1911. Contemporary with the construction of the railroad, aerial tram equipment was brought to the mines by pack train and a tramway, 3 miles, long, connecting Bonanza mine with the proposed railroad terminal, was finished, enabling shipments of high-grade ore to be made immediately on the completion of the railroad. A mill to treat the lower grade ore was begun the same year. The Kennecott company's holdings consist of 111 mineral claims. The Mother Lode Coalition Mines Co., which is controlled by the Kennecott Copper Corpn., owns 73 claims adjoining the Kennecott holdings. All data on operations and geology refer equally well to the Mother Lode property.

Jan 1, 1924

By Timothy F. McConachy, Christopher J. Yeats, Ray Binns

Various kinds of sediment-hosted polymetallic sulfide deposit are known on land in ancient marine sequences, many tending to be larger and more valuable than massive sulfide deposits genetically associated with volcanic host rocks. Often such deposits are attributed to subhalative or shallow sub-seafloor precipitation processes, and structural control by faulting is commonly evident. Apart from the famous but anomalous Red Sea metallic oozes and several NE Pacific sites (Middle Valley, Escanaba Trough, Guaymas Basin), however, modern analogs of the sediment-hosted polymetallic sulfide category are lacking. Some deposits hosted by volcaniclastic rocks, such as JADE (Okinawa Trough) and Suzette (Eastern Manus Basin) are strictly sediment-hosted, but their formation is associated with the igneous activity and they are better considered a variant of the more abundant volcanic-associated polymetallic sulfide deposits.

Aug 24, 2006

By Ross C

This paper uses the results of research trials by Landcare Research and Forest Research Institute and assessments of reclamation plantings at mines and other drastically disturbed sites to describe methods of enhancing restoration of native forests. The characteristics of mine and forest environments are compared to highlight the difficulties facing restoration and techniques which result in successful restoration are described. Selection of the most appropriate technique is illustrated by describing restoration of lowland beech-podocarp forest at a West Coast coal mine. The key to successful reclamation is to understand the factors controlling and limiting plant establishment and growth, then to design rooting media, surfaces and management regimes to create a favourable environment. This paper concludes with a summary of the planning and technical factors which are critical for successful restoration of native forest.

Jan 1, 1995

By S. Duma

The main sulphide zone (MSZ) of the Great Dyke is cryptic and without obvious stratigraphic markers. Although there are trends in the dimensions of the PGE and base metal profiles across the Hartley Complex, the profiles are invariant within a particular mining area. Ratios derived from these profiles are used to interpret diamond drill cores drilled ahead of underground development. Detailed logging of oriented core shows the exact position and attitude of intersected faults. Metal ratios are used to estimate fault throw to within 25 cm. It is possible to draw detailed sections showing the extent of ground disturbance well ahead of mining. The method has been confirmed by mining and by drilling inclined holes through the fault blocks. Keywords: main sulphide zone, Hartley Complex, Great Dyke, Zimbabwe, platinum, Palladium, Nickel.

Jan 1, 2004

By Michael A. Linkous, Mark J. Zdunczyk

Silica in the form of sand and sandstone is one of the most common, and at the same time, unique industrial minerals. Found in every rock type of every geologic age and virtually everywhere in the world, silica is used in products that touch just about every aspect of daily life. Imagine a world in the 1990s without computer chips, fiber optics, or glass, and you have just begun to understand how important silica is to the quality of life we enjoy. The elements silicon (Si) and oxygen (0) comprise roughly 60% of the earth's lithosphere to a depth of about 16 km. The crystal structure of silicon dioxide consists of one atom of silicon bonded to four surrounding atoms of oxygen to form a three-dimensional network of SiO, tetrahedra. This network makes up the mineral quartz (Murphy and Henderson, 1983), the most common detrital mineral in most sandstones. Quartz is also a major constituent of many igneous and metamorphic rocks and is widespread as a siliceous cementing agent in various rock types. Although quartz is common, sandstones, quartzites, and pegmatites and the unconsolidated sediments derived from them that have a silica content high enough and pure enough to meet today's market demands for quality and consistency are not common. USES AND SPECIFICATIONS Silica sand that is mined and processed for industrial uses must conform to the chemical and physical specifications set by customers. In the United States almost half of the silica sand produced is used in the manufacture of glass. Other important products include foundry sand, ground silica, blasting sand, and fracturing sand. Glass Sand Silica is the principal glass-forming oxide in a glass batch. Glass manufacturers develop model specifications for each source of silica sand used. These specifications broadly define the limits and ranges for chemical and physical properties of the sand and are used by the manufacturer in calculating the desired batch mix or formula. Some specifications may be critical to a glassmaker and require very stringent limits on the quantity of impurities in the sand. For example, the total iron oxide content of a batch is extremely crucial when making white or flint glasses (Mills, 1983). Iron is present in almost every raw material used in a glass batch and must be carefully controlled in order to obtain a consistent color in the finished product. It is difficult, however, for a raw material supplier to tightly control the chemistry of a naturally occurring material such as silica sand. To a great extent the commercial quality of a sand is determined by its geologic history. Realizing this, glass producers tailor their model specifications to each source of approved material. In general, a glass company is concerned most about the consistency of raw materials on a day-to-day basis. Soda-lime-silica glass was the earliest type of manmade glass (Baker-Can, 1967) and still accounts for most of the glass manufactured for commercial use today (Mills, 1983). It is relatively easy to melt and shape and is less expensive per ton to produce than most other types of glass (Baker-Can, 1967). Soda-lime-silica glass is used in fabricating containers, flat glass products, incandescent and fluorescent lamps, glass fiber, and many other products. Heavy minerals such as ilmenite, leucoxene, kyanite, and zircon are impurities on which strict limits are placed for a glass batch. Because of their refractory nature they either do not melt or only partially melt, which results in stones or feathers in finished glass. Aluminosilicates such as kyanite also contribute unwanted alumina to the batch as they partially melt. Limits are especially rigid for refractory mineral grains coarser than 0.60 to 0.425 mm (30 to 40 mesh). [Tables 1 and 2] present typical specifications for silica sand used in flat glass and container glass products. The percentages shown represent an average of many companies7 specifications.

Jan 1, 1994

By H. D. Wilde

At the Sugarland and Raccoon Bend fields in the Gulf Coast area, all wells are drilled with rotary tools and the casing is always set in cement that is placed by the circulation method. After the cement is set, the rotary mud that fills the hole is not withdrawn or bailed out; consequently, it is not customary to give the cementing job a direct test either by putting pressure on the hole to see whether the cement will hold or by observing whether an effective water shut-off is secured. About three years ago, this company started the practice of coring the cement left in the bottom of the casing and examining the core thus secured. If the core was hard and strong, the cementing job was judged a success but if the core was incoherent, soft, and crumbly, the job was considered a failure. Of course, there were intermediate types of cores and it was not always a simple matter from this examination to decide whether the job was a success or failure. After about two years, a summary of the core examinations that had been made indicated that of cementing jobs made at depths of 1000 ft. or less, 60 per cent.. were failures; of those between 1000 and 2000 ft., 80 per cent. were failures, and of those between 3000 to 6200 ft., 100 per cent. were failures. This sta,rtling table emphasized the need of the study of the conditions under which the wells were cemented and of adopting means to reduce the percentage of failures. In addition to these core tests, two wells gave direct evidence that the cementing jobs were not always successful. In one, a four-year-old well at Goose Creek, the casing was perforated, and when fluid was circulated some of the old cement wss brought to the surface. Most of it was powdery and the few chunks that were brought up were soft and crumbly. The other was a well at Raccoon Bend which during a blow-out brought a number of chalky, soft and crumbly pieces of cement to the surface. Suggested Explanations of Cementing Failures Efforts were made at once to explain the causes of these cementing failures. As all of the cements used were of a high grade and gave

Jan 1, 1930

By Glenn Keep

THIS paper is not an announcement of the successful conclusion of the Cerro de Pasco Copper Corporation's pacos-pyrite problems, but merely a description of the commercial-scale, intermittent-roasting operations conducted by the writer, J. H. Lucas and others of the staff. It was prepared by request, for presentation at the February meeting of the Institute. The results obtained in Peru confirm the 1-ton-a-day experiments completed about three years ago at Kearny, N. J. by C. C. Gordon and Mr. Lucas, where it was first demonstrated that a mixture of about 80 per cent. pacos ore with 10 per cent. pyrite ore and 10 per cent. salt could be roasted intermittently in a small 1-ton-a-day Holt-Dern furnace without extraneous fuel, producing porous calcine that could be leached rapidly. Mr. Keep and his staff, by successfully introducing improvements in the construction of the commercial furnace and in their handling of material, have established beyond doubt a low cost for roasting. The other steps in the process of treating pacos and pyrite ores have not as yet been demonstrated as sufficiently conclusive to warrant their acceptance for a permanent plant.

Jan 1, 1929

By William Glenn

The taking of proper samples of crude ores seems to he less thoroughly understood, or less carefully practiced, than its impor tance requires. We all know how often we encounter the reports of very accurate assays and analyses, the weight of which as evidence wholly depends on the method of obtaining the sample, and is very probably nil, because there has been no proper sampling. Pissages might be cited from technical books, and from current technical literature (all the work of writers whom we delight to honor) to show that even among high scientific authorities there is too little acquaintance with the practical art of the sampler. There is no metallurgical or chemical establishment which does not frequently receive samples truly representing nothing. They consist usually of bits of ore, or what not, selected because they are worse or better than the average of what they are meant to represent. And they are worthless, no matter who made the selection. Where conscious choice is permitted to enter into the operation, a fair sample will not result, unless by a miracle. The work of sampling is often looked upon as within the realm of boys and of pensioners only. At least, though the manual labor be left to subordinates, the principles on which it is conducted and the safeguards with which it is surrounded are not unworthy of the study of experts; and experts should he ready to teach these principles and enforce them in practice. For exact sampling is the indispensable first step towards learning the value of any boxful, carload or shipload of ore. I propose to give a simple account of the method of sampling by hand, such as I have always pursued. There is nothing new about it. So far as I know, it is the immemorial old method, as old at least as Cornish copper-mining. Perhaps my fellow-members in the Institute may suggest improvements in it. If not, it will constitute a record in our Transactions to which laymen and beginners may be referred.

Jan 1, 1892

By J. O. Marsden

Over the past eight years, Phelps Dodge (a division of Freeport-McMoRan Copper and Gold, Inc.) has developed a suite of proprietary hydrometallurgical processes for the treatment of copper concentrates as an alternative to conventional smelting and refining technology. The technical viability of two processes has been commercially demonstrated in a large scale plant at Bagdad, Arizona, designed to process approximately 52,500 metric tons per year of concentrate containing 30.5% copper. The first process utilizes high temperature (225°C) pressure leaching, followed by countercurrent solid-liquid separation, and then blending of the copper-bearing solution with low grade stockpile leach solution for subsequent treatment by SXlEW for copper recovery. The second process uses super-fine grinding, medium temperature (l60°C) pressure leaching, followed by solid-liquid separation, and treatment of high grade copper-bearing solution by direct electrowinning to recover the bulk of the copper values. The latter process will be utilized at Morenci in a commercial facility designed to treat mixed chalcopyrite-chalcocite-covellite concentrates. This facility is scheduled to start up in 2007. Other flowsheet options have been developed by Phelps Dodge for application to a variety of concentrate materials in specific situations. Examples of various flow sheet options are presented in this paper, and the advantages and disadvantages associated with each are discussed in detail.

Jan 1, 2007

By D. I. Bardos

The occurrence of Laves phases (AB,) in various binary alloy systems has been reviewed in recent papers.13 Iron forms Laves phases with Sc-, Ti-, V- and Cr-group elements. However, two of the corresponding Laves phases with cobalt, namely MoCo, and WCo,, are missing. Nickel forms binary Laves phases with Sc and Y, but not with any Ti-, V-, or Cr-group element. These conditions are schematically illustrated in Table I. That electron concentration is a significant factor in determining which type of Laves phase is formed in a given case was recognized long ago by Laves and Witte,4 This concept has been more recently applied to Laves phases formed by transition ele-ments. It now appears that the average electron concentration (average number of electrons per atom outside of the closed shells of the component atoms) may be an important factor also in determining whether or not a Laves phase can occur at all in a given system. As shown in Table I, in the transition element systems considered Laves phases are absent at electron concentrations of 8, or larger (to the right and below the double line in Table I). These absences clearly cannot be accounted for on atomic size considerations, as evidenced by the many inconsistencies apparent in Table 11. While the ideal radius ratio for Laves phases is 1.222, in the systems which do have Laves phases the ratios of CN 12 radii range from 1.10 to 1.46. The consistent absence of Laves phases at RA/RB< 1.10 might be attributed to the low values of these radius ratios. However, Table II shows that absences also occur irregularly throughout the radius ratio range covered. In a previous paper7 it was concluded that, in transition element systems forming u-phases, silicon may act as an acceptor of electrons, thus stabilizing the u-phase at electron concentrations higher than

Jan 1, 1962

By E. S. Machlin, A. J. McEvily

HE results of an experimental investigation by McEvily and Machlin have indicated that a strong relationship exists between the processes of cross slip and fatigue. Whenever dislocations can cross onto an intersecting plane and expand thereon, as in AgCl crystals, the usual type of S-N behavior is obtained, but when such a process is difficult, as in NaCl crystals, fatigue does not occur in its usual manner, if at all. MgO, because of its crystal structure (NaCl type) and slip systems ({110}<110>) would not be expected to fail in fatigue. However, Cornet and Gorum2 have found something akin to the usual type of fatigue behavior for MgO crystals. The purpose of this note is to attempt to resolve this apparent discrepancy. In Cornet and Gorum&apos;s work as-cleaved crystals were tested under cyclic axial loading, whereas in McEvily and Machlin&apos;s work chemically-polished crystals were tested in reversed bending. Because of the difference in specimen preparation, the major effort of the present work was directed toward comparing the behavior of as-cleaved as opposed to chemically-polished specimens. The effect of type of loading seemed less important, but a check was made on this also. Eighteen bend tests and one axial load test were made. The specimens were cleaved from Norton magnorite blocks, and measured 1 by 3/16 by 1/8 in. To avoid failures in the grips, the thickness of the bend specimens was reduced from 1/8 in. near the ends to 0.04 in. in the central portion. This reduction was from one side of the crystal only. Twelve specimens were polished in orthophosphoric acid to remove the damage due to cleavage. The other six specimens were not chemically polished so as to maintain the as-cleaved condition of the crystal faces which had not been reduced. The axial-load specimen was reduced from both faces to a thickness of

Jan 1, 1962

By S. Gering, R. Ruiz, C. H. Calderon-Arteaga, J. Barrios

"Located in the northeast corner of Zacatecas State, Mexico, the Peñasquito operation is comprised of the Peñasco and Chile Colorado (Brecha Azul) deposits. Openpit mining (prestripping) began in 2010 and full production commenced during 2011. The openpit mines feed both a sulfide concentrator (mill) and a heap leach pad. The project is owned by Goldcorp Inc. Peñasquito is a poly metallic deposit with Au, Ag, Zn and Pb being recovered as payable metals.As a consequence of lower grade ores expected with advancing mine life, Peñasquito is facing a declining metal production profile. To maximize returns and asset value, plant modifications, including the addition of a carbon prefloat circuit and a pyrite leach circuit to improve recovery, are currently being undertaken. This carbon prefloat circuit will enable the recovery of precious and base metals from carbonaceous sediments. This material is currently being stockpiled. With the associated increase in complexity in the process circuit, the requirement of the ore control system to accurately predict ore feed characteristics is critical to maximizing metal recovery at the Peñasquito operation. The addition of the carbon prefloat circuit was also a key driver in allowing the Chile Colorado openpit to be developed.These conditions alongside Goldcorp’s drive to increase profitability and maximize net asset value has created challenges. These challenges are numerous and multifaceted. However, the ability to accurately route materials from the ore control system is critical to site success, and some of these challenges have been overcome by the adoption and implementation of a new ore control (OC) technology. Examples of these technological innovations in the ore control program are discussed in this article and include improvements in geomodeling, material routing and reconciliation. Successful implementation of these elements has led to significant improvements in selectivity, performance and data management, while reducing the variance between planning and execution, thus helping to drive overall improvement across the operation."

Jan 7, 2018

By F. H. Daniels

IN this, paper it is my intention to, call your attention to* a few of the many producers using blast, now, in common use in Sweden, and also those constructed by the Washburn & Moen Manufacturing Company at their Quinsigamond Works. During a prolonged stay in Sweden the writer had an opportunity

Jan 1, 1881

By F. H. Daniels

IN this paper it is my intention to call your attention to a few of the many producers using blast, now in common use in Sweden, and also those constructed by the Washburn & Moèn Manufacturing Company at their Quinsigamond Works. During a prolonged stay in Sweden the writer had an opportunity

Jan 1, 1881

By Tom Plouf, Deepak Malhotra

INTRODUCTION The U. S. mining industry experienced a severe recession in the early 1980&apos;s. This resulted in the realization that the domestic mining industry had to compete on a global basis and only the strong or the low-cost producers would survive. The economic viability of a mining company not only depended on maximizing mineral recovery but also on its ability to do so at minimum cost. Companies had to become more productive not only by cutting costs, but also by developing and/or evaluating new technologies in existing or new plants. Several innovative concepts, including in-pit crushing and conveying, fine crushing, improved classification equipment, flotation, column flotation, pressure filtration, etc., have been developed in recent years. This paper addresses the impact of new flotation concepts and equipment on mill design. MILL DESIGN PHILOSOPHY Modern mill design, especially for large capacity plants, has its foundation in minimizing capital and operating costs. Capital costs can be minimized by minimizing the various components of the capital cost: infrastructure, equipment, instrumentation, structural, initial spare parts costs, etc. All these costs are minimized by simplifying the mill design and/or process flowsheet. The simplified process flowsheet, where applicable, consists of a single stage primary crusher followed by a semiautogeneous - ball mill grinding circuit to produce feed for a flotation circuit. Multiple flotation circuits have been eliminated in most cases. These concepts minimize the cost and encourage the use of large capacity equipment while maintaining optimum metallurgical recovery. The philosophy of mill modernization/modification is generally driven by the desire to increase the mill capacity within the limits of the existing mill building. This need is facilitated by using large size flotation equipment and eliminating multiple parallel flotation circuits in order to minimize capital and operating costs. Conventional flotation machine development has paralleled this mill design philosophy. FLOTATION CELL DESIGN Since froth flotation has been the most widely used separation process for over half a century, one would expect that it would be possible to design and select flotation machines for specific applications based on scientific principles. But this has not been the case. Best judgment, experience and personal prejudice have played a key role in equipment selection. These factors, along with the difficulty of evaluating new concepts in commercial plants, has slowed progress in implementation and commercialization of innovative ideas and/or equipment. Conventional Flotation There have been no major technological advances in conventional flotation cell design in recent years. A recent flotation cell survey indicates that &apos;larger flotation cells are still the order of the day.”(1) A comprehensive review of design of flotation machines indicate that they have been mechanically redesigned and are generally simpler and easier to maintain and less expensive to manufacture. (2,3) The approximate chronological development of conventional cells from the 25 cubic foot cells to the 3000 cubic foot cells, which were recently installed at the Copperton concentrator of Utah Copper, is given in Table 1. Larger flotation cells are the obvious choice for new plants or plants looking for expansion because of the following reasons: • They have lower capital cost per unit volume • Installation costs are generally lower because fewer units require less space • Maintenance costs are lower because of fewer mechanisms • Power requirements (HP/ton dry feed) are generally lower • with increased flotation cell size as illustrated in Table 2 [Table 1. Conventional Flotation Cell Size Development Year Individual Cubic Cell Size, Feet 1925 25 1935 50 1960 100 1965 300 1970 500 1975 1,000 1980 1,500 1985 3,000]

Jan 1, 1989

The company was formed in 1926 to exploit tin bearing veins adjacent to Aberfoyle Creek in north-east Tasmania. In 1928 a 923ft tunnel was driven to explore and develop the mine 150ft below surface. This put the company on a path to become Australia&apos;s second largest tin producer by the late 1960&apos;s. Recently, Aberfoyle Resources Limited completed a 1.1km tunnel to access the major Hellyer zinc, silver, lead orebody at 300m depth. Production at 1 million tonnes a year is likely, and will make the company a significant world supplier of zinc by the late 1980&apos;s. The intervening 20 year history of survival and diversification illustrates principles of mineral exploration which proved valid in the Australian context. The objective of exploration should be to develop mines which can survive rigorous competition and downturns in commodity prices. Such mines will be based on orebodies with many of the following characteristics described by Richards (1986).

Jan 1, 1987

By Jörgen Appelgren

Atlas Copco, a leading supplier of equipment and services to the mining and construction industries, is consistently pursuing its strategy to offer the most productive and economical solutions by continuously offering new innovative products. These are in most cases developed and tested in close cooperation with demanding end users before being officially launched on the international market. The demands for higher productivity and improved overall economy have resulted in systems for automation of the drilling cycle and also tools for integrating the Drilling equipment to the production control system used by the customer. In terms of improving the blasted material quality, Atlas Copco has placed emphasis on hole straightness and the need for hole logging and positioning. By applying state of the art technology to today?s computerized drilling rigs, major steps in improving overall drilling and blasting performance have been achieved. This paper will give some examples derived from the latest development of solutions for the Rotary drilling product line.

Oct 1, 2009