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By David M. Spatz

Anyone who scans the modern literature will realize that concepts of leadership have changed during the past few years. And like change in so many areas of our culture, change has been rapid in the perception of leadership. Many traditional leadership traits are still highly regarded and many of the longstanding personal qualities that improve leadership abilities continue to be effective. In the past, though, leaders could rely on dominance, intimidation and fear to accomplish their goals through the actions of others. In contrast, effective leaders today build relationships, provide vision and guidance, and strive for communication, cooperation, trust and employee satisfaction. Earnest leadership involves moral issues like honesty, integrity, fairness, empathy and respect. Modern leaders guide, facilitate and coach, rather than command and direct. But how well equipped are managers in the mining industry to meet the leadership challenges that lie ahead? More importantly, is he or she becoming a better leader? This article outlines steps to becoming a more effective leader. Management consultants stress that the changes that lie ahead will demand swift organizational adjustments and managers who are equipped to lead during times of change (Boyett and Conn, 1991; Hesselbein et al., 1996; White et al., 1996 and Kotter, 1997). Becoming a better leader begins with self-assessment and a commitment to unify all who depend on one's leadership abilities. Simply defined, leadership is leading others. Contrary to common practice, leadership is not about advancing one's own career but about bringing out the best in others. The beauty of modern leadership, however, is that the path of serving others creates synergies. They benefit everyone, including the leader, those the leader manages, upper management and company shareholders.

Jan 1, 1998

By E. G. Kelly

Many methods of evaluating the efficiency of mineral separations have been described in the literature. In most cases, these present the efficiency as a single number. This paper argues that single-number measures of efficiency are inadequate because they seldom allow reliable comparisons, and are unlikely to correspond to the optimum operating conditions. To realistically make comparisons, it is necessary to distinguish the particle-induced component from the equipment- induced component. In a number of situations where the separating property can be identified (such as in gravity concentration and classification), this can often be done. However, in more complicated systems, such as flotation, this has not been possible. A technique is described whereby particle and equipment contributions to efficiency can be distinguished without the need to define the separation property. Because smelter schedules define a boundary correlation between grade and recovery, they generate some of the better single¬-number measures of efficiency, but even these have limitations.

Jan 1, 1991

By James R. Tompkins

This paper details the successful progression of a promising exploration property into a producing gold mine in only 35 weeks on schedule and on budget. While under construction, an extensive exploration program continued to add to the mine life through the increase in reserves, resulting in a decision to increase the mill capacity from 500 tonnes per day to 1000 tons per day while maintaining the original construction schedule. Details are provided on the unique geology at the Puffy Lake Gold Mine, development from the exploration stage through construction and ultimately to production, with a detailed flow sheet. In addition, of note is the successful change over from contract mining to the hiring of Pioneer personnel who are successfully carrying on both stope mining and development. Operating costs per ounce of gold production are projected at $185 U.S. and alternate methods of mining are currently being examined which could further reduce operating costs.

Jan 1, 1988

Some basic terms used in cost management and accounting include: - Cost. A sacrifice made to acquire goods or services, measured by the price paid. Technically, the sacrifice is called a cost until the benefits from the goods or services have expired, at which time the sacrifice is called an expense. In this text, the terms "cost" and "expense" are used interchangeably. - Revenue. An increase in the value of the firm resulting from the sales of goods and services. - Income. The excess of revenues over costs for a specified period. The term is often used with modifiers to indicate specific quantities on an income statement (e.g., pretax income; net income). - Activity. A measure of production work. Traditionally, physical production volume (tons of ore or units of product) has been used as the measure of activity. Other measures include direct labor hours, equipment operating hours, and quantity of materials or supplies consumed. - Responsibility center. A segment of an organization that is responsible for a specified set of activities. In mining, individual operating divisions can be treated as responsibility centers, known as profit or cost centers. Departments within a division are generally treated as cost centers. - Cost center. A portion of an organization having responsibility for achieving specified levels of cost. - Profit center. A portion of an organization having responsibility for achieving specified levels of profit (revenues and costs).

Jan 1, 1999

By Donald A. Brobst

Barite, the sulfate of barium, occurs in many geological environments in sedimentary, igneous, and metamorphic rocks. The commercial deposits of barite may be classified into three major types. 1. Vein and cavity fillings that occur in rock fractures, along bedding planes, and in various solution structures. 2. Bedded deposits in which barite occurs as the principal mineral or cementing agent in stratiform bodies in sedimentary rocks. 3. Residual deposits occurring in unconsolidated material formed by the weathering of preexisting rocks. The geologic characteristics of each type of deposit are of fundamental importance to the successful search, development, and economic use of barite deposits.

Jan 1, 1980

By John W. Sweeney

Florida is usually thought of as a vacation State, not a mining State, yet Florida has been the leading producer of phosphate rock in the United States for 85 consecutive years and in 1978 supplied over 80 percent of the national output and over 30 percent of the world's output. It is estimated that the Central and South Florida phosphates contain 412,800 short tons (374,000 metric tons) of U308, that 115,000 short tons (104,000 metric tons) of U308 will be contained in the wet-process phosphoric" acid procsssed in the United States through the year 2000, and that 54,000 short tons (49,000 metric tons) of U308 will be available from Florida. In 1978, two companies in Florida and one in Louisiana went on-stream recovering uranium oxide from wet-process phosphoric acid and three others started construction of U308 extraction facilities. These six companies will have the capacity to recover 2,137 short tons (1,900 metric tons) of U308 annually in 1980, which will account for about 15 percent of our domestic requirements.

Jan 1, 1979

By I. L. Jennings

In most industrialized countries, the largest element of the mining industry in physical volume is that devoted to the extraction and processing of materials for use as construction aggregates. Required for all developments in industry and commerce, power and transportation, and housing and public services, their use is so widespread that possible sources are exploited throughout all geographic regions, as close as possible to the point of use. Thus, it is also the most frequently encountered form of mining throughout the world. These materials come from four main sources:- (a) Excavation of unconsolidated deposits of sand and gravel (b) Stone quarrying. (c) Processing of slags and other mineral wastes. (d) Manufacturing from clays and shales by heat fusion. The major uses are in: (a) Portland cement concrete, that most versatile of construction materials, including the many concrete products in current use. (b) Asphalt cement concrete; widely employed for paving roads, parking lots, airfields, etc. (c) Foundation materials, such as road base, granular backfills, railway ballast, etc.

Jan 1, 1968

Geopolymerization is a process by which Al-Si minerals undergo dissolution and polymerization in an alkaline solution to form a monolithic material with a high mechanical strength (Davidovits, 1991; 1994). In this study, Na-feldspar (albite) and K-feldspar (microcline) have been selected to investigate their abilities to undergo geopolymerization. The interaction between alkali metals present in the alkali-feldspars and alkali metal cations contained in alkaline solution during geopolymerization has also been studied. It has been found that both albite and microcline can be applied in geopolymerization to produce geopolymers with a high compressive strength. Although the dissolution of M-feldspar (where M = Na and/or K) in concentrated MOH solution is inhibited when the alkali metal cations of the alkaline solution differ from the alkali metals structured in M-feldspar, the resulting geopolymers are found to demonstrate a higher compressive strength. Moreover, a proper molar ratio of Si/Al in the geopolymeric gel phase and a higher average hardness of the undissolved particles remaining in the geopolymers are found to greatly increase the ultimate compressive strength of the geopolymers.

Jan 1, 2002

By Ronald J. Allain

Water soluble polymers play an important role in many industries. The mining industry is dependent on these materials to help accomplish many solid-liquid (water) separations. Mechanical devices alone are not capable of achieving the degree of separation needed. Mechanical and chemical separations act in concert to accomplish the necessary separation. The history of the use of water soluble polymers has gone through several evolutionary phases and I believe we are facing another of these phases. At first, various natural products were common - starches, gums, and various polysaccharides. These were replaced by the synthetic polymers based on copolymerization of various vinylmonomers mainly in conjunction with acrylamide. The use of these polymers and their needs continues to grow. This paper will cover a brief overview followed by a look at the future of water soluble polymers. A focus will be on applications of water soluble polymers in the mining industry.

Jan 1, 1994

By W. W. Edgerton

Construction projects may be delivered under one contract package or multiple packages divided by discipline, geographic location, or other characteristics. Dividing the construction into contract bid packages is called contract packaging, and is a vital and strategic aspect of effectively delivering tunneling projects. The process of contract packaging considers many factors, including the type of project, location, and owner?s priorities. This paper describes the key facets of the contract packaging process used recently on several tunnel projects, reports, where possible, on the success of the process, and concludes with recommendations for applying this process to achieve the right contract package.

Jan 1, 2008

By John M. Smith

Kaolin is an important industrial mineral because of its unique properties and low cost. Strictly defined, kaolin is the name given to a group of hydrous aluminum silicates of which kaolinite is the most common mineral (1). Through common usage the mineral, kaolinite, is called "kaolin" or "china clay". In 1972 over 4, 000, 000 tons of kaolin will be beneficiated and shipped by domestic producers. By far the largest user of kaolin is the paper industry which utilizes approximately 65 to 70 per cent of the total production. Kaolin is used in paper as a filler in the interstices of the sheet and as a coating to impart smoothness, gloss, brightness, and printability to the paper. The rubber industry is also a large user of kaolin where it is used as a filler because it adds strength, abrasion resistance, and rigidity to both natural and synthetic rubber goods. Kaolin is used as an extender in paints because it is chemically inert, has a high covering power, gives desirable flow properties, and is low in cost. In ceramics, kaolin is used in whitewares, tile, insulators, refractories, and in some face brick where a white color is desired. Kaolin is also used extensively in plastics as a filler in thermosetting and thermoplastic mixes to give smoother surfaces, a more attractive finish, good dimensional stability, and resistance to chemical attack. Many other process industries use kaolin as a filler, suspending medium, or for color improvement.

Jan 1, 1972

By Charles E. Joachim

Current Army tunnel destruction criteria (1) are based on limited nuclear-explosive (NE) and high-explosive (HE) test data. The PILE DRIVER (2) and HARDHAT (3) events investigated tunnel and support system response where yields were relatively large and tunnel diameter small compared to typical underground openings and localized stress fields of low yield weapons. Some limited tunnel destruction information was obtained from underground events of the PLUMBBOB and HARDTACK II Series (4). These events used access drifts which were designed to be self closing at the weapon point. The limited NE data are augmented by HE results from the Underground Explosion Test (UET) Program, a series of model and prototype-scale experiments in granite and sandstone (5). Weapon standoff distances (charge c.g. to tunnel wall) were at or near the maximum for major damage. Limited tunnel destruction was produced by a series of hasty and deliberate tests (6) on abandoned railroad tunnels in basalt. Additional HE data were obtained from model tests at the Waterways Experiment Station (WES) (7) using 2.1 MJ (2 lb) TNT charges and tunnel diameters varying from 3 to 17 cm (1.2 to 6.6 in). Recent laboratory scale HE experiments (8) conducted at the WES under the ESSEX program investigated the effects of tunnel diameter, standoff distance, charge confinement, material strength and to a limited extent, tunnel spacing and liner strength variations on tunnel damage. This paper summarizes the analysis conducted to develop predictions for the effects of low-yield nuclear weapons against tunnels and underground openings in rock.

Jan 1, 1979

By Peter W. Scott

The Caribbean islands, with their very diverse geology, are a source of several industrial minerals both for their own domestic consumption and for export. The geology of the Greater Antilles, which comprises Cuba, Hispaniola, Puerto Rico, and Jamaica has a Mesozoic or pre-Mesozoic basement overlain by sediments and volcanics, the latter being dominantly island arc in character. Later granitoid intrusions were emplaced. Obduction of ophiolites also occurred variously from the mid- Cretaceous to the Palaeogene. Thick accumulations of limestones surround the older strata, along with Neogene and younger sediments. The Lesser Antilles islands form an arcuate chain, mainly of volcanic rocks of calc-alkali or sub-alkaline affinity with some younger limestones and siliciclastic sediments. Trinidad and Tobago have closer similarities with the South American continent in their geology. Tobago has a metamorphic complex, juxtaposed with a volcanic-plutonic complex, and limestones. Trinidad has very thick Cretaceous to Recent exposed sedimentary sequence. The current exploitation of industrial minerals in the Caribbean is dominated by construction raw materials (mainly sand and gravel, limestone, and cement), although there is extraction of gypsum, silica sand, marble, clay (almost entirely for construction use), pumice, and natural asphalt. Salt is obtained from solar evaporation of seawater. Limestone of high purity and high brightness, gypsum, pumice, and high-density igneous rock have potential for further development of their markets, particularly ex- ports. Potential new and undeveloped industrial-mineral resources include residual and sedimentary kaolin, bentonite, zeolites, magnesite, and talc. Cuba could be a source for many industrial minerals in the future.

Jan 1, 1999

By W. D. Blackburn

If there is a single key to managing a mineral extraction company, it is the control of productivity. American labor costs, in general, tend to be in the range of 10%-15% of total costs. American coal mining labor costs, however, exhibit ranges of 30%-60% of total costs. Is it any wonder that the industry finds itself at a competitive disadvantage? When labor costs take as much as sixty cents of every dollar of revenue, there is little room for profitability. The American coal mining industry must set as a long range goal the reduction of labor costs to the 10%-15% range of total costs in order to be competitive.

Jan 1, 1986

By Christof Brewka

Los Pelambres, 200 km north of Santiago, Chile, is the latest in a series of mega-projects developed in this part of the world. While most of its predecessors are spread over open desert, the Los Pelambres mine is nestled inside a narrow alpine valley high in the Andean Mountains. To handle the daunting task of transporting the mined copper ore more than 12 km and 1,400 vertical meters downhill to the concentrator plant, a gigantic belt conveyor system (capacity of 8700 mtph, 1800 mm wide ST 7800 steel cord belt, 2.5m diameter pulleys, an elaborate braking system including a mechanical failsafe and large reducers with a total installed drive power of 25,000 kW) has been employed. Many of these components have pushed the limits of conventional belt conveyor design.

Jan 1, 2000

By John Wiebmer

Six industry trends will have significant effect on the way mining equipment is designed and supported in the years ahead: 1. MINING IS MIGRATING TO LESSER DEVELOPED PARTS OF THE WORLD The global recession of the early 1980's drove down commodity prices and intensified cost competition. This caused a fairly dramatic trend in mining away from higher cost operations in developed countries to richer, lower cost deposits in developing countries. Miners operating in lesser developed parts of the world will place higher value on rugged, durable designs that can live in more difficult and sometimes abusive conditions. They need engines and power train systems that are more tolerant of a wide variation in fuel quality and oil specifications. They'll require machines that are simpler to operate, simpler to maintain, simpler to troubleshoot and simpler to repair. And they'll require creative means of support in getting technical information, parts and components to remote operational sites. Mining equipment in the future will be more durable and simple than it is today, and product support will grow in importance as purchasing criterion. 2. THE MINING INDUSTRY IS CONSOLIDATING An intense amount of corporate acquisition and industry consolidation activity is occurring, to the point that today just 50 mining companies account for 55% of the western world non-fuel mineral production. Consolidation will continue, leading in the future to an industry structure weighted heavily toward a few key global mining houses.

Jan 1, 1993

By Robert L. Bates

An industrial mineral, says the Glossary of Geology, is "any rock, mineral, or other naturally occurring substance of economic value, exclusive of metallic ores, mineral fuels, and gemstones; one of the nonmetallics." Probably most geologists and engineers would accept this simple and straightforward definition, at least as a general statement. On analysis, however, certain anomalies crop up. For example, what is metallic and what is nonmetallic? Bauxite and ilmenite certainly qualify as metallic ores, but both are also raw materials of important nonmetallic substances; hence they are included in this book. Another anomaly is that, by common consent, the term industrial minerals may include not only rocks and minerals but also certain manufactured products, such as cement and lime, and even mixed groups of natural and artificial products, such as abrasives and refractories. Thus the central realm of the industrial minerals is clear enough, but its boundaries tend to be indefinable. Since a definition that allowed for every irregularity in the outer fringes would be excessively unwieldy, the one quoted above may be considered satisfactory. The expression industrial minerals is commonly equated with nonmetallics, and with the somewhat more precise phrase industrial minerals and rocks as in the title of this book.

Jan 1, 1994

By Anthony G. Fonseca, W. W. Wen

About 45-50% of the coal mined in the U.S. passes through coal preparation plants; east of the Mississippi River this number increases to about 75-80%. Although the cost for coal preparation is worthwhile to some, the coal industry faces the challenges of continuing downward pressure on the price of coal and the impact of new environmental regulations. Coal preparation, as commercially practiced today, is an effective process achieving 75-803 ash reduction, 15-8m trace element reduction, and 85-90% Btu recovery; it is less effective for pyrite reduction (35-70%), and on-line operating time (40-60%), and suffers from obsolete control systems. Methods will be discussed for reducing costs of coal preparation and improving the performance of coal preparation plants. Comments are included on equipment selection, especially for -28 mesh coal, and prep plant operation and control practices. Btu recovery, ash and pyrite reduction, fines processing including dewatering and slurry fuel use options are emphasized. Trace element removal and expert control systems for maximization of prep plant operation also will be highlighted.

Jan 1, 1995

By T. E. Burns

The process engineer is frequently requested to select equipment to separate brine from solids, In many cases, this is a more difficult task than the selection of most other pieces of process equipment because quite often the operation of the various types of debrining equipment cannot be predicted by calculations, One must rely to a great extent upon experience or empirical test work to predict performance - that is to say one must use a practical rather than a theoretical approach. This is not to say that the solutions to liquid-solids separating problems are wholly an art but rather it is to emphasize that the approach demands a fair knowledge of commercially available liquid-solids separating equipment, some background on the advantages and limitations of each type and in many cases might necessitate a fair amount of test work, or at least, a study of performance of equipment on similar applications.

Jan 1, 1966

By William H. Hamilton

INTRODUCTION It was not very many years ago that tunneling machine manufacturers spent considerable time trying to convince contractors and mine operators of the advantages of mechanical tunnel boring over conventional drill and blast methods. Today there are few doubters left. There is universal agreement that, not only are tunneling machines here to stay, but the ratio of bored rock tunnels to blasted rock tunnels is increasing at an accelerated pace, and within the next twenty years I predict almost all tunnels will be bored by machine. I believe we are today at a very important mile-post in the development of tunnel boring systems. Felix Gaye stated in his recent article (1) "It is important to disseminate between the efficiency of cutting tools and the overall efficiency of the boring operation". Mechanized tunnel boring in the past placed almost total emphasis on the rock cutting and boring ability of the tunneling machine. With advancements in technology and better solutions to the problems of rock fracture, steering control, and structural design, the emphasis today can be placed on the total-system concept. Tunneling machine design, as one of the key elements in the overall system, presents many problems that are not totally solved today. These design problems are, in the most part, not related with rock fracture, but rather with criteria associated with the over-all operation.

Jan 1, 1997