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By Staff

The mineral sector is a fundamental part of the U.S. economy. It contributes to the real gross domestic product (GDP) at several stages—basic (mining), intermediate processing, manufacturing of finished goods and construction. The estimated growth rate for the real GDP of the United States for 2006 was 3.2 percent. The nominal GDP was about $13.2 trillion. The value of minerals mined in the United States in 2006 rose significantly because of increased unit price for some metals—particularly copper, zinc and other base metals. There was also a significant reduction in metals stocks. Infrastructure expansion and manufacturing in China and India have been absorbing a significant portion of world output. Domestic production increased for some industrial mineral materials, mainly cement and construction sand and gravel. Production of crushed stone declined less than 1 percent in 2006 compared

Jan 1, 2007

By William A. Vogely, Robert T. Deacon, Walter J. Mead

Oil and gas together are the most important energy sources consumed in the United States. In 1983, 67% of total energy consumption was represented by these two resources (43% was oil and 25% natural gas), while coal accounted for only 23% of U.S. energy use. All other sources (hydroelectric, nuclear, geothermal, wood and other waste products) accounted for only 10% (U.S. Department of Energy, 1983, p. 1). In this chapter we address the issue of regulation in the oil and natural gas sectors of the U.S. energy industry. In addition, we analyze the cartel characteristics of the Organization of Petroleum Exporting Countries (OPEC). If OPEC is an effective cartel, then U.S. oil as well as substitute energy prices, production, and consumption will be affected by cartel action. Further, as the nation learned in the 1970s, major changes in oil prices produced major disturbances in other sectors of the U.S. and world economies. Consequently, it is important to determine whether the roughly ten-fold increase in nominal prices that occurred in the 1970s was the result of cartel action, the result of normal economic forces adjusting to the fact that the world was running out of cheap oil, or some combination of the two. Furthermore, the presence of OPEC- associated oil price increases is related to regulations that were imposed on the energy sector during the decade of the 70s. THE RATIONALE FOR GOVERNMENT INTERVENTION Economists have traditionally judged the state of an economy to be efficient if it is impossible to improve the welfare of any one member of society without harming someone else. Any economy that satisfies this condition is said to be Pareto efficient, after the Italian economist Vilfredo Pareto who first gave rigorous attention to such questions (see Chapter 4.10). It is easy to see why an economy that fails to satisfy this condition could not be efficient; by definition, it would be possible to alter the allocation of resources in a way that improves everyone's welfare.' Much of the appeal of this weak efficiency criterion is that it avoids comparisons of levels of well being among different individuals. The cost of such generality, however, is that in any given economic system a wide array of different Pareto efficient states will typically be attainable. In the simple Robinson Cursoe economy of the undergraduate textbook, for example, efficiency could just as easily be attained in the case where most of the island's resources are owned by Friday as in the case where they are under Crusoe's control. However, the distribution of welfare among the two inhabitants would obviously be quite different in the two situations. Such equity issues cannot be settled on objective or scientific grounds. To decide which distribution of welfare is socially "best" an explicit value judgment is needed. It is useful to keep in mind the preceding distinction between efficiency and equity issues when analyzing the role of government in a market economy. Decentralized market processes will not necessarily result in a distribution of welfare that society considers just. For this reason a potential role for government lies in the redistribution of income among individuals. In some circumstances, however, market pro-

Jan 1, 1985

By George Hope, Jacques McMullen

Recent process advances at Lac Minerals Est Malartic Division are discussed. The Est Malartic mill treats massive sulphide, copper/gold ore from the Bousquet 2 mine, to produce a gravity gold product, a copper flotation concentrate and a gold precipitate. The mill operation has been improved by the application ofKnelson concentrators to replace jigs, the application of Outukumpu high grade tank cells and optimizing the cyanide leach to minimize cyanide consumption.

Jan 1, 1993

By Raymond E. Zimmerman

The use of standard dense-media cyclones is well known, as they have been in use for many years. They are especially well suited for operating at low separating densities and for treating difficult coals containing a high percentage of near-gravity at the point of separation. Very few modifications of the basic design have ever been made. The author recently, however, has been interested in the development of a new type of dense-media cyclone that has been produced in Japan. He has observed the testing of this unit and has collected much data which he feels should be of considerable interest to coal preparation engineers. He feels that this unit, called the Swirl Cyclone, may be of substantial value as an alternate to the standard cyclones. It is certainly worthy of further investigation. There has been relatively little written in English-language publications on the Swirl Cyclone. It was briefly described at the Fifth International Coal Preparation Congress. I It has been described in a general manner by the author in two prior publications. 2, 3 This paper proposes to describe this device in more detail and at the same time submit technical data illustrating its wide characteristics.

Jan 1, 1977

By M. R. Yalamanchili, J. D. Miller

Discussion by M.R. Yalamanchili and J.D. Miller The authors, M. S. Celik et al., should be recognized for their efforts to describe the flotation behavior of boron minerals. In the case of borax and other soluble salt minerals, analysis of the flotation chemistry has been difficult because of the high ionic strengths associated with these soluble salt systems. However, considerable progress has been made in this area, and recently a surface charge/collector colloid adsorption model was proposed by Miller and his coworkers to explain the collector adsorption phenomena observed in soluble salt flotation systems (Milleret al, 1992; Yalamanchili et al., 1993; Miller and Yalamanchili, 1994; Yalamanchili and Miller, 1994a: Yalamanchili and Miller, 1994b). In this work, the sign of the surface charge of alkali halides in their saturated brines was established on the basis of nonequilibrium electrophoretic mobility measurements by laser-Doppler electrophoresis (Miller et al., 1992). Generally, these results are what would be expected from the simplified lattice-ionhydration theory. This electrokinetic information coupled with the stability and prevalence of collector colloids in such soluble salt flotation systems indicates that the selective flotation of alkali halides is due to the adsorption of oppositely charged collector colloids by heterocoagulation. Experimental flotation/bubble attachment results for 21 different alkali halides (Yalamanchili et al., 1993; Yalamanchili and Miller, I994b) confirmed that the flotation response of soluble salt minerals with weak electrolyte collectors can best be explained by the adsorption of oppositely charged collector colloids rather than by the adsorption collector ions and/or neutral molecular dipoles as originally suggested by many researchers (Fuerstenau and Fuerstenau, 1957; Schubert, 1967; Roman et al., 1968). In addition, the flotation of certain alkali oxyanions (Pizarro et al., 1993) and double salts such as schoenite and kainite can be explained by the same collector colloid adsorption mechanism (Miller and Yalamanchili, 1994). The borax flotation results reported by Celik et al. need to be examined in terms of the above mentioned surface charge/ collector colloid adsorption model. Unfortunately, the authors seem to be unaware of this recent work that nicely describes soluble salt flotation with weak electrolyte type collectors such as amines and carboxylates. In view of our past work, the flotation characteristics of borax were of particular interest, and, in this regard, the results of dodecyl amine flotation of borax reported by Celik et al. have been examined in further detail in the light of experimental results from our laboratory. In our research, a vacuum flotation technique was used to study the flotation response of borax (Na2B407.10H20), which has a solubility of 39 g/L at 25 °C) with dodecyl amine hydrochloride as collector. These chemicals were purchased from Eastman Kodak and used as received. Saturated solutions of borax at desired pH values were prepared by continuously stirring the salt solutions over a period of about 10 hrs. It should be mentioned that the conditioning time to achieve equilibrium is an important variable and can significantly change the flotation response of some soluble salts (Yalamanchili et al., 1993). Collector was added to the saturated borax solutions containing about one gram of 100x 150 mesh borax particles, and conditioning was done for about 20 minutes prior to flotation. The borax flotation recoveries from saturated brine are presented in Fig. 1 as a function of collector addition at the natural pH of 9.3, as reported both by Celik et al. and as measured in our laboratory. In addition, the region of precipitation for the dodecyl amine hydroborate is included in Fig. 1. It can be seen in Fig. 1 that the flotation response curves are separated by about one order of magnitude in R12NH3CI collector addition. The flotation results of Celik et al. show that the maximum borax recoveries can be obtained below the solubility limit of the dodecyl amine hydroborate collector. However, in our experiments borax flotation seems to occur only after the precipitation of the dodecyl amine hydroborate collector as might be expected from the collector colloid adsorption model (Yalamanchili et al., 1993) if borax were negatively charged. Further analysis by nonequilibrium and equilibrium electrophoretic mobility measurements for borax indicates that borax is negatively charged at the natural pH of 9.3, as discussed below. The reliability of the nonequilibrium electrophoretic measurements has been demonstrated previously for alkali halides and alkali oxyanions (Miller et al., 1992; Miller and Yalamanchili, 1994). The equilibrium and nonequlibrium electrophoretic measurements for borax were found to be consistent and are presented in Table 1. These results provide clear evidence that borax carries a negative surface charge in its saturated brine (pH 9.3), and the sign of the surface charge of borax reverses and becomes positive if the pH is reduced to 8.6. The equilibrium between borax and its saturated brine can be described by the following reaction: [2Na2B407.1OH2O-4Na++B407=+HB4O7 +OH+19H20] It appears that the oxyanions of the borax lattice provide

Jan 1, 1995

By L. R. Duncan, W. H. McCracken

Magnesium is the eighth most abundant element in the earth's crust and the third most plentiful element in seawater. It is found in more than sixty minerals and in brines and seawater as a magnesium salt. One of the more important magnesium minerals is magnesium carbonate, MgCO3, with a theoretical maximum magnesia, MgO, content of 47.6%; this carbonate form represents the world's largest source of magnesia. The next most used sources for magnesia are magnesia-rich brines and seawater, where it occurs as magnesium sulfate and magnesium chloride. Other commercially important magnesium-bearing minerals are dolomite, CaMg(CO3)2, which serves the aggregate industry as well as the chemical industry; brucite, Mg(OH)2, which is used in the production of both caustic and sintered magnesia; olivine, ([MgFe]2-SiO2), which serves the refractory and heat storage industries; talc, (H2Mg3(SiO3)4), which serves several industries as a filler and as an ingredient in cosmetics; and serpentine, (H4Mg3SiO9). All these minerals are of commercial value because of the desirable characteristics given to them by magnesia and by its placement in the crystal structure. These minerals are the starting raw materials for a wide range of products. These include the production of magnesium metal, and several grades of magnesia used for the production of both sintered magnesia for refractory manufacture and lighter fired caustic magnesia, the latter is used in fluxes, fillers, insulation, cements, decolorants, fertilizers, chemicals, in the treatment of waste water including pH control, and in the removal of sulfur compounds from exhaust stacks. Magnesite is one of several major minerals possessing a dual character, i.e., non-metallic industrial mineral because of its principal end use as a calcined/dead burned raw material in non-metallic end products and magnesium metal. A large percentage of the magnesia used to produce magnesium metal comes from seawater1 brines. The total primary metal production worldwide is about 350 ktpy. This report reviews magnesite solely as an industrial non- metallic raw material. Magnesite for most refractory purposes must have a content of sintered magnesia above 85%, with a preference for those sources that have the potential for 90 to 98% magnesia values. Dolomite, used in large tonnages because of its physical properties in the construction industry, also has a use in the chemical and the refractory industry. In its calcined form, dolomite is used as a slag addition in the making of steel, and it is used in a high-purity calcine to precipitate magnesium hydroxide from brines or seawater. The precipitated magnesium hydroxide is intermediate for the production of deadburned clinker for refractories and the production of magnesium metal. In many cases the high-purity magnesium hydroxide obtained by precipitation with calcined dolomite, or in some cases limestone, has supplanted much of the world's production of magnesia from the natural mineral magnesite. This is especially true of the United States and in major industrialized areas of Europe and Japan. The best known of the minerals directly and widely exploited for its magnesia content is magnesite (MgCO3), one of the calcite group of rhombohedra1 carbonates, which includes calcite (CaCO3), siderite (Fe2CO3), and rhodocrosite (MnCO3), among others. The members of this group enter into a wide range of substitutional solid solutions when the positive ions have similar radii. The radii of magnesium and iron ions are within 6% of each other; hence magnesite and siderite form a complete series, of which the mineral breunnerite (ferroan magnesite) is a well known end member. The radii of calcium ion is 36% larger than that of magnesium ion and only limited substitution exists at each end of the MgC03-CaCO3 series. Dolomite is not a member of the calcite group, but it occurs when calcium and magnesium ions alternate in equal number in an ordered structure among carbonate ions. The result of this relationship is that calcite and dolomite are commonly found intermixed with magnesite. They occur, commonly, as identifiable crystal entities, which can be separated to a varying degree from the magnesite by benefication techniques. Magnesite, when pure, contains 47.8% MgO and 52.2% CO,. The pure mineral is found occasionally as transparent crystals resembling calcite. Magnesite principally contains variable amounts of the carbonates, oxides, and the silicates of iron, calcium, manganese, and aluminum. Although the genesis of natural magnesite deposits can be complex, it is distinguished in nature in two distinct physical forms, namely crystalline, (with a wide range of visible crystal sizes) and cryptocrystalline, sometimes referred to as amorphous, where the crystal size is not detectable to the eye and will range from 1 to 10 pm. The two types not only differ in crystal structure but in the sizes of the deposits and in modes of formations. The crystalline form has a Mohs hardness of 3.5 to 4.0. The color range is from white to black with shades of yellow, blue, red, or gray. The color is not a significant indicator of purity but in a given deposit an experienced person can often roughly grade the magnesite by observing color and crystallinity. Macrocrystalline deposits occur in relatively few, but generally large, deposits on the order of several million tons. The ore shows a marble-like crystal structure and belongs to the sedimentary or metasomatic groups of origin. The cryptocrystalline variety of magnesite frequently occurs in many small deposits, although there are exceptions. Cryptocrystalline magnesite is typically massive with no cleavage and is sometimes descriptively called bone magnesite. The fracture is usually conchoidal, with a hardness of 3.5 to 5.0. The color is mainly white, but it can have tints of yellow, orange, or buff. Accessory silaceous minerals such as serpentine, quartz, or chalcedony are usually present. Calcium minerals are normally absent or in low concentration, this contrasting with the macrocrystalline form where calcium minerals are almost invariably present and some- times in high concentration. The specific gravity of cryptocrystalline magnesite ranges between 2.90 and 3.00, whereas the value of pure crystalline magnesite is 3.02. In actuality, the normal specific

Jan 1, 1994

By Gennaro G. Marino

During the preliminary design stages of the Illinois Division of Natural Resources(DNR) building, it was discovered that an old coal mine was present some 70 m (220 ft) beneath the building site. The new DNR building to be constructed is 36 m (120 ft)wide and 134 m (440 ft) long. It has three stories above grade and abasement level. The building is oriented north-south and has east and west ponds next to it (Fig. 1). The building is located on the State Fairgrounds in Springfield, IL. Given the history of surface subsidence of these underground coal mines in the Springfield area, there was concern about the potential for future subsidence at the building site. Mine subsidence events in the area have resulted in more than 0.9 m (3 ft) of settlement and have caused significant structural damage.

Jan 1, 2000

By C. K. C. K. Gupta

The rare earths in elemental form are required for a variety of scientific and technological purposes. They are not easily obtained in this form, due to the great chemical stability of the rare-earth compounds and the strong tendency of elemental metals to react with everything they come in to contact with, especially at high temperatures. Beginning in the 1950s, when sufficient quantities of separated rare earths became available, as the result of intense research and development, three processing routes were developed to accomplish the preparation of all 16 naturally occurring rare-earth elements. They are chemical reduction of the halide intermediates, the oxides and electrochemical reduction of chlorides and oxide-fluoride mixtures. Not all the processes are effective with all the rare earths. In spite of the celebrated similarity of trivalent rare earths, the physical properties of individual rare-earth elements are sufficiently different that a variety of techniques are required for their preparation. The development of reduction processes for the rare-earth metals are covered in this paper, with focus on the oxide reduction routes. The strong reliance of effective reduction processes on the fundamental science of reduction reactions is highlighted.

By Kirk H. P. E. McDaniel, Mark T. Strever, Keith G. Jr. Wallace

This paper presents the design and installation of an underground ventilation remote monitoring and control system at the Waste Isolation Pilot Plant. This facility is designed to demonstrate safe underground disposal of U.S. defense generated transuranic nuclear waste. To improve the operability of the ventilation system, an underground remote monitoring and control system was designed and installed. The system consists of 15 air velocity sensors and 8 differential pressure sensors strategically located throughout the underground facility providing real-time data regarding the status of the ventilation system. In addition, a control system was installed on the main underground air regulators. The regulator control system gives indication of the regulator position and can be controlled either locally or remotely. The sensor output is displayed locally and at a central surface location through the site-wide Central Monitoring System (CMS). The CMS operator can review all sensor data and can remotely operate the main underground regulators. Furthermore, the Virtual Address Extension (VAX) network allows the ventilation engineer to retrieve real-time ventilation data on his personal computer located in his workstation. This paper describes the types of sensors selected, the installation of the instrumentation, and the initial operation of the remote monitoring system.

Jan 1, 1995

By Hisashi Takahasi, Hironobu Yamazaki

INTRODUCTION The slurry shield method was developed in Japan in 1963 and its experimental tunnelling work was performed in 1965. Although the history of this method is short compared with the conventional shield method in Japan, many companies such as Tekken Construction, Okumura Gumi, Nishimatsu Kensetsu, etc. are engaged at present in developing their own unique system of the slurry shield method. The ground of Japan is generally pervaded with ground water and a large number of districts are covered with soft ground, which is composed of fine sand, silt and clay, etc. Therefore, the conventional shield method has always used compressed air with various kinds of auxiliary methods. However, with this method there have been experienced numerous troubles such as ground settlements, lowering of ground water, oxygen shortage within the tunnel, and so forth. The slurry shield method has been developed with the above background. In recent years remarkable progress has been made from the engineering viewpoint in applying this method to driving various kinds of tunnels such as road tunnels, subways, water supply and sewer tunnels, and other tunnels. Apart from Japan, the slurry shield process using bentonite is carried out in England and Germany. OUTLINE OF SLURRY SHIELD METHOD (1) System of Slurry Shield Method Since the conventional shield method drives tunnels using com-

Jan 1, 1976

By Scott G. Britton

This chapter is concerned with the construction of the dynamic component of belt haulage systems. The dynamic system includes the belt line and tailpiece extension and retraction movements in a production system where mine management is continually placing the belt in the most effective operating position. Correct installation of the belt and tailpiece during an extension is very important for many performance reasons. Two of the most important reasons are to eliminate spillage and safely operate the belt line. This chapter is divided into three major discussions. The first discussion looks at analyzing the parameters of effective belt line construction. This includes a review of the parameters and management tools needed for proper scheduling of a move-up. The second major discussion topic centers on efficient procedures for a belt line extension. Topics such as site preparation, tailpiece breakdown and setup, stringing the belt line and structure, plus operating and maintenance tasks needed after the belt line is installed and running, are covered. The third discussion presents a list of conveyor and conveyor component manufacturers who provide services and products to the coal mining industry. Again, any discussion on underground haulage systems must generalize much of the site specific design approaches to be practical. This text will mention, where applicable, some of the alternatives available to construction engineers in designing belt line systems.

Jan 1, 1983

By John W. Brauns

18.1-RAILROAD JOHN W. BRAUNS Conventional railroad haulage can be employed at both open-pit or strip and underground mines-in the latter case, largely for transfer of ore from distant openings to processing plants, or processed material to loading points or docks, using standard hopper cars for bottom unloading or gondolas for rotary dumping. The major application, however, is in surface mining for moving ore and/or waste out of the pit to a crushing plant or dump. Consequently, the following will deal largely with this phase of railroad operation, though the conclusions apply equally, for the most part, to other rail-type surface haulage. In surface mining, trains consisting of a locomotive and gondola or side-dump cars suitable for loading by power shovels are used. Gondolas are restricted to hauling ore as a rotary dumper is required. Side-dump cars are more versatile, carrying both ore and waste, but because of their additional dumping mechanism they are likely to be more expensive to maintain.' Also they weigh up to twice a flat-bottom car of the same capacity and. therefore, fewer" cars can be hauled per train. Standard-gage track is most commonly used. Track systems incorporate low-quality temporary track where moves are frequent and permanent high-quality track on main lines. Rail haulage can be used alone, or in combination with other surface haulage methods, thus permitting a selection best adapted to the peculiar requirements of each mining project. 18.1.1---GENERAL APPLICABILITY, CONTROLLING PHYSICAL CONDITIONS For handling rough rock, the shovel-train system is unexcelled.' The ideal applica¬tion is in a large, but not excessively deep, open pit mine from which the coarsely blasted ore and waste must be transported over 3 mi. If. in addition, a high production rate is to he maintained, railroad haulage probably will afford a lower cost per ton transported. Grade must he relatively gentle-usually 3% uphill and 4% downhill. The greater the differences in elevation involved, the greater are the track grade space requirements; for example, a 3 c ramp out of a pit only 300 ft deep is almost 2 mi long. Main-line track locations should he selected carefully so that the number of moves during the life of the mining operation can he kept to a minimum. This applies both to the ore haulageway and that for waste. Such moves are not only expensive, but are difficult to execute without adversely affecting production rates. The large mine affords greater opportunities for judicious location of semipermanent trackage. Figs. 18-1 and 18-2 illustrate typical track layouts. The effect of terrain in considering railroad haulage is confined chiefly to the initial cost of the installation. Grade construction in mountainous territory is ap¬preciably more expensive. However, if that expense can be borne, the subsequent maintenance cost of trackage will not he much higher than in areas of low relief.

Jan 1, 1973

By Z. T. Bieniawski

After many significant advances in mining including development of sophisticated methods for strata characterization and numerical modeling analyses, the engineering design process in mining is as primitive as it was two decades ago. Yet, major advances in design methodologies have occurred in other branches of engineering. Is creative design in mining a myth only? Are we deluding ourselves when we talk about innovative mining design of today? What is the reality of the situation? This paper explores the methodology of creative engineering design as a new recognized discipline. It warrants applications in mining since design experts are sometimes unaware of their own decision-making processes.

Jan 1, 1988

Ceremonies for the induction of five mining industry pioneers into the National Mining Hall of Fame are scheduled for Saturday, Sept. 25, 2004 at the Las Vegas Hilton in Las Vegas, NV. The 17th Annual Mining Hall of Fame Induction banquet will begin with a reception at 6 p.m., followed by the dinner and program at 7 p.m. The five inductees are Georgius Agricola, David William Brunton, Herbert E. Goodman, David Ray Mitchell and Robert Peele. Georgius Agricola (1494-1555) wrote De ReMetallica, an original and valuable work that discussed everything known about mining during the first half of the 16th century. In De Re Metallica, Agricola reviewed practical means of finding ores, methods of surveying and mining, the assaying of ores, types and uses of mining machinery, smelting, mine administration and more. David William Brunton (1849-1927) is best know

Jan 1, 2004

By J. M. Mutmansky

This paper outlines the results of a study of opinions of practicing engineers concerning the value of environmental engineering courses in a mining engineering curriculum. One hundred engineers with significant experience in mining-related engineering work were carefully chosen. Of the sixty-seven responses received, about half were from mining engineers and half from environmental engineers. The results of the survey are outlined in detail. The number and type of courses recommended by the respondents are summarized as well as the specific topics recommended for inclusion in a mining engineering curriculum. The survey form also asked for the stages in the mine life when environmental experts were needed and the percentage of environmental engineering performed by outside experts for many mining-related environmental tasks. The results of this line of questions are provided. Finally, the paper offers a comparison of the results for environmental engineers and mining engineers and analyzes the differences.

Jan 1, 2001

By J. M. Mutmansky

This paper outlines the results of a study of the opinions of practicing engineers concerning the value of environmental engineering courses in a mining engineering curriculum. One hundred engineers with significant experience in mining-related engineering work were carefully chosen. Of the 67 responses, about half were from mining engineers, and the other half were from environmental engineers. In this paper, the results of the survey are outlined. The number and type of courses recommended by the respondents are summarized as well as the specific topics recommended for inclusion in a mining engineering curriculum. The survey form also asked for the stages in the mine life when environmental experts were needed and the percentage of environmental engineering performed by outside experts for many mining-related environmental tasks. The results of this line of questions are provided. Finally, the paper offers a comparison of the results for environmental engineers and mining engineers and analyzes the differences.

Jan 1, 2003

By Roy Norcross, Stephen Gos

For over 100 years Degussa has worked together with the min­ing industry not only providing quality products but also develop­ing technologies to support these products through value added goods and services. For cyanide, these technologies include leach enhancement processes such as PAL™ and Solidox™, and cyanide detoxification with peroxygen based processes such as SILOX™ and Caro's acid using our DegOX™ technology. Degussa has also made important advances in how sodium cyanide is packaged and shipped with our liquid NaCN plant joint venture with MSI, CYANCO in Winnemucca, Nevada, and our Advantage SLS™ solid to liquid cyanide delivery system. All of these innovative technologies developed to support NaCN in mining, provide value to our customers and show Degussa's commitment to Responsible Care·11.1 and dedication to product stewardship. With Responsible Care and the customer in mind, Degussa has developed Advantage CCS™ cyanide control system, which will soon be available for the North American market. Currently there are several CCS units in service installed by Degussa AG (Germany), and we are in the process of designing the next gen­eration of the CCS which should be completed by late '98. Based on our experience working with gold and silver mines all over the world, there appeared to be an opportunity to further assist our customers by providing a better more automated way to control their cyanide additions. By providing the mine with an accurate method for maintaining their desired cyanide levels in their leach circuits, we could help them avoid underdosing and the associated gold and silver losses, and overdosing the cyanide which not only wastes cyanide but may increase treatment costs as well. In the early 1990's, when we began to introduce our CCS units, there were several cyanide controllers and on-line analyzers avail­able. However, they appeared to be too complicated and not made to stand the harsh conditions inside a mill. This resulted in exces­sive downtime and poor analytical results. We also found that many units would be installed but not commissioned by the sup­plier. Based on these observations, along with filtration and con­trol problems on some existing units, Degussa decided to design its own cyanide control system based on our extensive knowledge of cyanide chemistry, using the best components available worldwide.

Jan 1, 1998

By D. Mohapatra

Extraction of Al(III) from aqueous sulfuric acid solutions into organic Cyanex 272®-carbon tetrachloride systems was investigated from a multi-component mixture containing aluminum, cobalt and nickel. Al(III) extraction efficiency was quantitative with 1.0 M Cyanex 272® in two stages at an aqueous: organic (A:O) phase ratio of 1:1 and an equilibrium pH of 3.2. The stripping of Al(III) from the loaded organic (LO) with different acids indicated sulfuric acid to be the best stripping agent. More than 99% stripping of Al(III) from the LO was achieved using 2 M H2SO4 at an A:O phase ratio of 1:1 in a single stage. The stoichiometry of the extracted species of Al(III) was determined by the slope analysis method. The extraction reaction proceeded via the cation exchange mechanism and the extracted species was assumed to be AlA3?3HA, where HA refers to the dimeric and A the anionic form of the extractant, Cyanex 272®. The extraction of Al(III) was studied in the presence of various ions to ascertain the tolerance limit of individual ions.

Jan 1, 2008

By D. Jepsen

Land access and tenure certainty for exploration and mine development is absolutely critical to the foundation of a healthy, sustainable and environmentally-sound mineral exploration and mining sector. Without certainty, mineral exploration will be severely eroded, resulting in reduced possibility of discovering and developing new mines. The development of positive relationships based on a shared commitment of understanding, mutual respect and trust by First Nations and the mineral sector can provide this increased business certainty and social and economic benefits for local First Nations. As a sector, we face many challenges in regard to building relationships with First Nations. The root solution to addressing these challenges lies in recognizing and understanding the unique cultural differences that exist between indigenous people and the business community. From the Canadian perspective, the First Nations culture differs vastly from non-Aboriginal culture. It is equally as imperative that cultural differences be acknowledged and respected at home as they are when seeking business opportunities in other countries. The traditional “business” approaches and relationships that one understands and incorporates with one’s contractors, legal counsel, investors and Board are generally not be the best approach for the introductory and subsequent meetings with indigenous peoples. This paper is written from the perspective of my experiences accumulated over the past ten years, first as Manager of Aboriginal Affairs for one of the largest forest companies in British Columbia and now, as President and CEO of the Association for Mineral Exploration BC (AME BC). My opinions are not necessarily endorsed by AME BC. Before the gritty issues of consultation and benefit sharing are dealt with, it is worthwhile to clear up the confusion surrounding terminology. “Indigenous Peoples” is used in a global context; “Aboriginal Peoples” is used in the Canadian context therefore includes Métis, Inuit and First Nations Peoples. The term “First Nations”, in the context of British Columbia, perhaps has its roots in the fact that treaties have largely not been settled. Therefore it is important to reaffirm that British Columbia was not discovered. First Nations have resided in British Columbia since time immemorial.

Jan 1, 2007

By G. Rainville, I. Servi, F. Katrak

Despite the severe drought conditions that reduced farm requirements for industrial mineral products, most industrial minerals markets in 1988 continued their growth or, at worst, remained flat. Earlier projections of output declines did not materialize in most segments. Preliminary estimates of demand in Europe and Asia show strong growth for most industrial minerals. Profitability in industrial minerals in North America was best in those minerals that had a significant export market or were not strongly regional. Growth and price trends in the more regional industrial minerals markets in the US such as sand and gravel, crushed stone, and cement, more closely followed the broadly disparate regional economic conditions. For example, sand and gravel and crushed stone grew strongly in the Pacific Coast and northeastern markets but not as much as in the Southeast. Total growth for sand and gravel in 1988 is projected at about 3% above 1987 levels. Combined production is up about 27 Mt (30 million st) to 2 Gt (2.2 billion st). Following the relentless trend of foreign acquisition of US cement companies (currently about two-thirds are owned by foreign interests), several aggregate operations have been purchased by foreign companies. Notable among these in 1988 was the acquisition of Rinker Materials Corp. by CSR of Australia. The acquisition of this Florida-based aggregate and concrete operation will expand the current holdings of CSR in the southeastern US, with operations consolidated under the Rinker logo. In addition, Pike Industries of New England and J.L. Shiely Co. of Minnesota were significant aggregate producers that were acquired by foreign firms. New England's only cement manufacturer, Dragon Products, was acquired by a subsidiary of Cementes del Norte of Spain. Dravo continued to expand its influence in the lime and limestone markets. It became the major supplier of construction aggregates on the inland river system with its purchase of Cyprus Minerals' limestone aggregate operations in Kentucky, Louisiana, and Texas. Although lime production continued to grow from 14 to 15 Mt (15.7 to 16.7 million st) in 1988, lime imports decreased for the fifth consecutive year to 145 kt (160,000 st). In the more export-oriented industrial minerals markets, performance was generally very good for 1988. Soda ash enjoyed an excellent year, with its price up to $102.50/t ($93 per st). This reflected the tight market situation for soda ash, particularly in late 1988. Soda ash production in 1988 was 8.6 Mt (9.5 million st), reflecting the industry's improved efficiency. Particularly significant was the increase in caustic soda prices that led to increased substitution by soda ash. The export market remained at 2.1 Mt (2.3 million st). Phosphate production recovered to the 42 Mt (46 million st) level, a 12% increase despite a soft export market. The price, however, remained soft throughout the year. W.R. Grace sold its interest in its Florida phosphate mine and its phosphoric acid complex as part of its divestiture of the agrichemicals business. The strengthening of the major producers has continued as lower cost capacity has been idled. Future permitting of phosphoric acid facilities and development of reserves will be necessary to maintain current production levels beyond the mid- to late 1990s. Despite new developments worldwide in the titanium minerals market, strong demand has continued to apply pressure to price, with concentrate and slag prices going up. The demand for high quality slag as feedstock for pigment production has resulted in process improvements in South Africa (Richard's Bay) and in plans by Canada to import high quality ilmenite by 1991 to produce a 90% TiO2 slag. Although growth in industrial silica sand applications was small in 1988, concentration in the industry continued. Unimin continued to acquire silica operations. Unimin is now the nation's leading producer of granular silica. The end users of silica have consolidated further. Owens-Illinois purchased Brockway Inc., a leading container glass producer. Three companies now control 75% of the container glass industry. ECC continued to be an aggressive purchaser of industrial minerals operations throughout the world. It acquired Cyprus Minerals' calcium carbonate business as well as two operations in Italy. In addition, ECC continued its aggressive acquisition of kaolin (Australia) and aggregate producers. 1988 was a good year for industrial minerals markets worldwide. More importantly, though, it was a year that showed continuing consolidations of reserve ownership in the industry around the world. Barite AN. Castelli, Baroid Drilling Fluids Inc. US mine production of barite decreased 9.4% during 1988. Consumption (sold or used by grinding plants) increased by 37.9%. Imports are estimated to have increased by 21.2%. World mine production decreased by 9.8%, according to the US Bureau of Mines. The value of domestically produced barite, fob mine, decreased 4.6%, according to the Bureau. The declared value cif US port of all imported ground barite during the first 10 months of 1988 increased from $37.16/t ($33.71 per st) in 1987 to $37.92/t ($34.40 per st), according to Bureau figures. Nevada continued to be the leading producer of barite with 72% of the total, followed by Georgia and Missouri. The Bureau of Mines estimates 69% of US mine production was used as a weighting agent in drilling fluids. The other 31% was used in barium chemicals, glass, or as a filler. Most of the production from Missouri, Georgia, and Tennessee was used in the non-oilfield sector. Of the total consumption used by grinding plants and chemical manufac-

Jan 1, 1989