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By Jacek B. Stypulkowski

This paper discusses the challenges faced by the design team of the under-river crossings of electric transmission feeders in New York City, a densely populated urban area. The under-river crossing of a 345 kV feeder was initially designed as Horizontal Directional Drilling (HDD), but was redesigned as a utility tunnel because of site con¬straints on both sides of the river. Multiple studies addressed location, available tech-nologies and costs. Multiple soil investigation phases addressed design aspects of HDD, as well as tunneling. Contractual issues varied from a design build alternative with Geotechnical Data Report (GDR) to design tender approach with GDR & Geotechnical Baseline Report (GBR).

By A. Taylor, E. Thorn Corthay, R. Storey

In response to requests from its stakeholders, the International Standards Organisation is engaged in development of an international standard for Energy Management Systems (EnMS) which will become "ISO 50001". This new standard will build on the successes of both the EN16001 EnMS standard that has been used by dozens of European companies, as well as the ANSI/MSE 2000:2008 EnMS standard that is currently being used in several pilot projects in the USA and Ontario. This paper provides an overview of the key points of the EnMS standards, and describes how they can be used to drive sustainable energy reductions in the metallurgy industry.

Jan 1, 2010

By J. C. Franklin

The Spokane Mining Research Center of the Federal Bureau of Mines is placing major emphasis on chemical stabilization as part of the ground support program. Development of polymeric material suitable for bonding rock fractures around the mine opening is one phase of the program. Some of the problems that must be considered are viscosity, applicability, adhesion, cure times, strength, toxicity, and flammability. Epoxies and polyesters were investigated, but shrinkage in polyesters caused redirected effort toward epoxies. Test results with the latter showed that bonded fractures in mine-roof strata were stronger than the virgin rock. Further tests showed that polymeric materials have good potential for bonding, and in conjunction with polymer roof bolts, are expected to result in an economic and useful new support concept.

Jan 1, 1974

By Kirsten Corin, Margreth Tadie, Cyril O’Connor, Jenny Wiese, Wonder Chimonyo

"Relating flotation performance to the electrochemical characteristics of a pulp remains a complex issue both in fundamental research and in practice. For example, in the case of thiol collectors different Eh values can result in the formation of the dimer or the metal thiolate which may or may not enhance the hydrophobicity of the mineral. Reducing or oxidizing conditions in a flotation system, viz. changing the Eh value, are usually manipulated to achieve an optimum flotation response by the control of pH and dissolved oxygen levels in the system. It is also possible to vary the potential by the addition of modifiers such as sodium hydrosulphide (NaHS), sodium hypochlorite (NaClO) or hydrogen peroxide (H2O2). The objective of the present study was to investigate the effect of the addition of the oxidising agents, NaClO and H2O2, on valuable mineral recoveries and grades in the flotation of sulphides from a PGM bearing Merensky ore. Batch flotation tests were conducted at pH 9.2, the natural pH of the system, in the absence and presence of a xanthate collector and Eh modifiers, viz. NaClO or H2O2. Most importantly in this way it was possible to vary Eh at constant pH and DO levels. The results indicate that in the absence or presence of xanthate the addition of H2O2 reduced both the recovery and grade of copper and nickel. In the absence of xanthate, the addition of NaClO improved the recovery of copper slightly and both the recovery and grade of nickel significantly, but in the presence of xanthate NaClO addition resulted in unchanged copper recovery and grade, but those of nickel were reduced. Based on anecdotal evidence that the addition of trace amounts of a potential modifier could improve flotation performance further tests were conducted the results of which suggest improved flotation performance.INTRODUCTIONIn the Merensky Reef, platinum group minerals (PGM) are commonly associated with base metal sulphides (BMS) and this has an effect on the way in which these minerals can be concentrated by flotation (Vermaak, Venter & Pistorius, 2004; Wiese, Harris & Bradshaw, 2005; Schouwstra, Kinloch & Lee., 2000). A major problem stemming from this association has been reported to be the loss of valuable minerals (PGM) associated with the loss of BMS (Wiese et al., 2005) during flotation. Shackleton (2007) suggested that PGMs behave in a similar manner to sulphides during flotation. Therefore, in order to recover the PGM, base metals are targeted. There is thus a need to investigate ways to improve the flotation performance of the sulphide minerals. The electrochemistry of the flotation of sulphide minerals has been studied for over half a century and there is consensus that sulphide minerals float only under a suitable redox environment (Heyes & Trahar 1979). This implies that reducing and oxidizing conditions during flotation of ores such as Merensky can be manipulated/varied to achieve an optimum flotation response.During flotation, sulphide minerals interact with thiol collectors in an electrochemical reaction to form hydrophobic species at the mineral surface (Finkelstein & Goold 1972; Rand & Woods 1984). The sulphide minerals are semiconductors and their interaction with collectors involves transfer of electrons. As such, a potential difference results which is responsible for driving electrons between reacting species (Fuerstenau, Jameson & Yoon, 2007). The magnitude of the potential difference affects the relative energies of charge carriers (electrons) at the mineral/solution interface hence controlling the direction and rate of charge transfer or rate of reaction (Bard & Faulkner, 2001). In a mixed mineral system the mineral/solution interface potentials account for the mixed potential which is critical to the process of flotation (Chander, 2003; Woods, 2003)."

Jan 1, 2016

By Fredrick D. Palmer

The World is Turning to Coal Peabody?s View ?We believe the world is increasingly energy-short, led by unprecedented demand from population centers and economic hubs in Asia, the Middle East and South America ?This occurs as:?Traditional energy sources are clearly constrained, requiring coal-based alternatives?Energy-rich nations leverage political gain from their assets, and nations urgently look to improve energy security ?In this environment:?Oil, coal and gas face a greater long-term convergence, ?Coal?s traditional regionalized nature becomes global, and ?Coal?s compact energy form becomes an attractive source for liquids and substitute natural gas ?The world is blessed with an abundance of coal to help meet all human energy needs

Jan 1, 2008

By W. D. Mulholland

"I ASSUME that any effort on my part to deal with the question of the importance of the mining industry is going to be largely an exercise in preaching to the converted, but there are one or two aspects that I'd like to particularly mention.The first is that, in terms of almost all factors, the mining industry is a very important industry in Canada. It is important in terms of employment in relation to the gross national product of Canada and it is particularly important in the international trade of Canada. So far from being insignificant domestically, it is also an extremely important factor in the international picture. That's an important point to bear in mind, because as we talk about all the other matters we never can lose sight of the fact that mining management always has to be conscious of its international competitive position. It is something that one forgets at one's peril, and to a somewhat greater extent than is true of many other industries, those managements have to compete in an international context for their markets, to some extent for their people for specialized skills and of course for finance. In the evolution of domestic policies it is a very, very perilous step to take to impair that competitive ability of the domestic mining industry."

Jan 1, 1972

By Robert F. Randolph

Introduction This paper is a descriptive analysis of injuries and fatalities at small surface bituminous coalmining companies in Pennsylvania. The purpose of analyzing a specific industry sector and location is to identify issues that might be missed in a wider analysis. Other studies of small mine safety (e.g., Peters and Fotta, 1994, Randolph and Boldt, 1997) have shown that the relationship between safety and mine size is not a simple one. Some injury types occur at higher rates at small mines, while others occur at lower rates. Consequently, an analysis limited to a specific type of mining can help identify hazards and issues specific to that sector. The results of this analysis will be useful for directing training, intervention, and research efforts towards the most prevalent causal factors and incident types. Procedures and Definitions Data sources The primary sources of data for this analysis were files provided by MSHA containing information collected under Title 30 Code of Federal Regulations, Part 50. These files, commonly referred to as “Part 50 data”, are provided though MSHA’s Program Evaluation and Information Resources directorate. Two primary types of injuries were selected from the Part 50data: Fatalities (MSHA “degree of injury” code 1) and lost-time injuries, otherwise known as nonfatal with days lost (MSHA “degree of injury” codes 2 through 5). Lost-time injuries involve either actual days away from work or days of restricted activity or both. Fatality and lost-time injury incidence rates were calculated using the standard MSHA formula: Number of injuries per 200,000 employee-hours. Additional information on company sizes and mine ownership was provided by the Pennsylvania State University College of Earth and Mineral Sciences. Time span A five-year time span was selected for this study. More than a single year of safety experience is usually needed to capture a broad range of incident types. Many types of injuries, especially fatal injuries, can be extremely rare, and may be missed if too short a time span is selected. However, a time span that extends too far back may begin to suffer historical threats to validity. That is, incidents that occurred several years ago may be caused by hazards that have since been remedied or may be related to mining practices and conditions that no longer exist. A five-year span offers a practical compromise between these two concerns. Consequently, the MSHA Part 50 data files from 1993 through 1997 were used. The 1997 file was in “preliminary” form at the time of the study, so small variations from the final 1997 “close out” file can be expected. Based on past experience, we do not expect the close-out variations to have a significant impact on the findings.

By John Frostiak

"Kahama Mining Corporation Limited, a wholly owned subsidiary of Barrick Gold Corporation, poured the first dore bar and filtered the first concentrate produced at the Bulyanhulu mine on February 28, 2001. This event marked the completion of the initial development of the Bulyanhulu Mine – Barrick’s first mine located outside of the Americas.Bulyanhulu is a 2,500 tpd underground mine located in the Lake Victoria gold belt of northern Tanzania. Gold is recovered as a gravity concentrate and smelted on site to produce dore bars or collected in copper concentrate that is shipped to offshore smelters. The facilities were constructed to meet Canadian standards. Unit operations include single stage crushing, SAG milling, gravity recovery, flotation, thickening and dewatering. Tailings are converted to paste and returned underground as paste backfill or pumped to the surface tailing site. The surface paste tailing disposal system is believed to be first of its kind in the gold industry. Paste disposal has several advantages over slurry, including lower dam construction costs, reduced water losses, and lower reclamation costs. This paper describes the facilities and discusses the challenges faced during development and construction including logistics, lack of infrastructure, recruiting and training, security, and social issues as well as initial operating results.INTRODUCTIONBarrick Gold Corporation completed the Bulyanhulu mine development in 2001. Capital cost of the project was US$280 million. The mine produced 241,575 ounces from start of milling to year end at a total cash cost of $197 per ounce. Numerous challenges were overcome in the mine’s development due to the general lack of infrastructure in Tanzania and the mine’s location some 1200 km inland by road from the port of Dar es Salaam."

Jan 1, 2003

The Golden Cross project was a joint venture between Coeur NZ Ltd (80 per cent) and Viking Mining Company (20 per cent). The site is located in the Waitekauri Valley, 8 km north-west of Waihi, on the Coromandel Peninsula, in the North Island. The mine-site is situated close to the Coromandel Range Divide between the headwaters of the Waitekauri River and the Martoto Stream. The site has a history of Gold Mining dating back to 1892. The more recent mine comprised an open pit and underground gold and silver operation from December 1991 to April 1998, MacGillivray, Maton and Goldstone (2000).Doug Hood Ltd commenced the first of three contracts on site in September 1997 and was responsible for completing the final stages of open pit mining, landslide remedial works mine closure and rehabilitation works. The Mill Closure and Rehabilitation and Drainage Works contract, for which this submission relates, commenced in September 1999 and was officially completed by Doug Hood Ltd. on the 26 May 2001.This paper endeavours to highlight the project objectives and backgrounds them against the difficulties experienced with respect to the site-specific conditions, the design complexities and risks associated with the contract, from a contractorÆs perspective.

Jan 1, 2002

By E. J. Schmitz

The mining of the Triassic coals of the Richmond basin has been carried on, upon a larger or smaller scale, for more than a hundred years. Notwithstanding the close proximity of the field to a large city and to tide-water, assuring both a good home-market and cheap transportation, and notwithstanding the good quality of the fuel and the great thickness of the principal bed developed and worked, operations in this field have been conducted with but limited success. The basin comprises about 189 square miles, being from 24 to 31½ miles in length by 5½ to 10 miles in width. Not much more than one-tenth of this area has been explored in a practical and efficient way, and not over 1200 acres have been worked near and along the outcrops or edges of the coal. The practical mistakes which have been committed undoubtedly in a number of the mine-operations of the past, do not alone explain the unsatisfactory success and progress of the industry of this field ; nor can it be ascribed to the lack of local enterprise. Other reasons have to be looked for; and, as a principal one, the irregularity and the faulted conditions of the coal deposits must be pointed out. As a second cause, the indifference of the State government, which leaves the development of the field entirely to private enterprise, instead of aiding it by systematical and practical geological investigations, deserves to be mentioned. Nothing has been done by the State since the excellent work done more than fifty years ago by Professor Rogers, who could not at that time enter into the details of such

Jan 1, 1895

By Tsuchida N

The history of world nickel production has been affected significantly by the supply and demand situation and fluctuation of LME price of nickel metal. In the beginning of the 1980s, the decline of price and demand lead to the withdrawal of un-competitive producers and the shrinkage of the production capacity. During the same period, Sumitomo Metal Mining maintained the production level with continuous improvement of the traditional matte electrorefining process. However, Sumitomo has recognised that the continuous improvement alone does not promise us the ability to catch up with rapid changes in the world. In the meantime, Sumitomo intensively researched chloride hydrometallurgy and has developed the chloride process for the nickel refining. This includes the solvent extraction and chloride electrowinning in the mixed sulphide process and the chlorine leach of the anode slime arising from matte electrorefining. In the late-1980s, Sumitomo Metal Mining decided to develop a new nickel refining technology based on chloride hydrometallurgy. The new process was designed from the comprehensive aspects involving safety and the environment. Construction of the plant for the matte chlorine leach electrowinning (MCLE) process was commenced in 1991. The MCLE plant with a capacity to 2000 tonnes per month has been commissioned at Niihama since 1992. The process has provided high productivity, overall good economics and high quality of electrolytic nickel produced. After the establishment of the process, Sumitomo has maintained continuous improvement of the new process and has attained the best practice of the work classification.

Jan 1, 1996

Recently discovered Carboniferous bentonites are variable in charadeI and thickness, but being altered aeolian, ash-fall tuffs, they are probably extensive. Most are the Ca-montmorillonite type without the natural swelling characteristics of the Wyoming deposits, but their situation, thickness, and response to beneficiation through cation exchange may give them some potential as sources of future economic deposits.INTRODUCTIONLoughnan and See (1959) gave an account of bentonites and fuller's earth deposits of New South Wales. The most likely potential industrial sources were those occurring in the uppermost formations of the Newcastle and Singleton Coal Measures (Permian) in the Hunter Valley and deposited during epochs not marked by strong contemporary vulcanicity.One feature of the record of known occurrences at that time was the absence of bentonites from the thick volcanic sequences of the Carboniferous, but since this paper appeared, many bentonite beds have been discovered by the writer in the Carboniferous facies formerly known as the "Kuttung Series".The purpose of this contribution is to report briefly on the occurrence, genesis, mineralogy, and economic potential of these deposits which augment possible sources of bentonite near major industrial centres on the eastern seaboard.The potential world demand for bentonite would increase markedly with the trend to pelletization in the steel industry, if its use in this field became more general. More detailed mineralogical studies will be presented in later publications.STRATIGRAPHIC DISTRIBUTIONBentonite occurs at irregular intervals throughout a thick sequence of dominantly continental, plant bearing strata...

Jan 1, 1965

By W. L. Zeigler

DURING the middle 1880s, shortly after the discovery of silver-lead ores in the Coeur d'Alene district of northern Idaho, it became apparent that concentration of the ores would be necessary to obtain a profitable product. Too much siliceous material was present for direct smelting, and the majority of the ores found at depth were too low in metallic content for economic smelting processes at the time. As the ores occurred in quartzite shear zones with siderite and quartz gangue, a large quantity of waste material was present in all the mines. As the galena was not finely disseminated, this made possible relatively good extraction of the argentiferous galena by coarse concentration. The first concentrators consisted mainly of coarse crushing, screening and jigging, principally by Harz jigs, the slimes being treated on buddies. Later Wilfley tables took the place of sand jigs and vanners superseded the buddies. Because of the marketing conditions, no attempt was made until 1900 to effect a recovery on the zinc minerals present, which were found associated in varying amounts with the galena. All through this period, the greater part of the production was obtained from mines containing ore assaying high in lead and low in zinc. Parts of some ore bodies would be reversed in this respect, so that ores high in zinc were left intact. During the decade after 1910, several important mines, The Success and The Interstate Callahan, containing ores high in zinc, were put into operation and were a material aid in the needed zinc production during World War I. Gravity concentration by jigs and tables was used during this period, with bulk flotation increasing in popularity for the treatment of the fine material that had already been treated by ordinary slime concentrating machinery. No extra fine grinding for flotation concentration was thought profitable at the time. TAILINGS DISCHARGED INTO STREAMS From the start of mining and milling operations in this district until 1904, no attempt was made by the various mills in the upper district to impound or stack their tailings. They discharged them directly into the adjacent creeks or streams, to be carried away by high water. The Bunker Hill and Sullivan and the Last Chance mines, both in the relatively flat valley of the district, stacked huge piles of the coarse jig tailings on the near-by river bottom. Rain and snowfall are heavy in the Coeur d'Alene district, as it is on the heavily timbered Pacific slope of the Bitter Root Mountains. A heavy runoff occurs every spring and there is an occasional flood of disastrous proportions when warm "Chinook" winds accompanied by rain

Jan 1, 1947

By A E. Annels, I P. Hodkinson an, S P. Barr

Narrow vein systems represent an important source of gold, which have generally been exploited by small to medium sized companies. Their evaluation poses particular problems because of their grade and geological complexities. The determination of grade is arguably the most important activity in resource estimation, as it is generally grade and not tonnage that makes an orebody. This is particularly true of narrow vein-gold deposits whose resources are generally relatively small, though medium to high-grade (6 - 40+ g/t). They often display extreme grade anisotropy in all directions. Two grade populations are generally observed; 1) low, often subeconomic, background grades and 2) high-grades associated with discrete ore shoots. It is possible for gold to be distributed within the wallrocks as well as within the vein. Extremely high-grade values typify this style of mineralisation and require special consideration during grade estimation to determine if top cutting is valid or not. Estimation of both width and accumulation in 2D on vertical longitudinal projections or inclined planes have historically been used to evaluate narrow veins. Resource estimates based on traditional 2D methods is still widespread, but has in some cases been replaced by computer-based 3D modelling. Grade estimation methods are well-known, ranging from classical to geostatistical. Historically, classical methods such as inverse distance weighting have been used, though geostatistical indicator kriging methods are sometimes applicable. Geostatistical studies are driven by the production of reliable variograms, which in narrow gold veins is often problematic. It is generally difficult to define resources from drillhole intersections beyond the inferred and indicated categories with any confidence. In the majority of cases underground development is required to define measured resources and ore reserves. Trial mining/bulk sampling is often used to test estimated grades and also provides important data on ground conditions and the parameters relating to the proposed mining method required for ore reserve definition. Regular reconciliation should be undertaken between the estimated stope grades, grades indicated from stope/truck sampling and grades realised in the mill in order to determine whether correct evaluation strategies are being applied. The important feature of narrow vein-gold deposits is their strong geological controls; in response to this, geologists must understand the geology as best as possible.

Jan 1, 1999

By Healy T. W, Dixon D. R

The present study 'of pure ZnS and NiS and ZnS (marmatite) by detailed electrokinetic methods has shown that by careful control of experimental parameters much new' information on sulphide-water interfaces can be obtained. Time-dependent processes of alteration of sulphide surfaces are foHowed by electrokinetic methods and indicate that the isoelectric point of the surface depends on elemental sulphur coverage, oxidation product coverage, and the conditions which promote or minimize such reaotions in the presence and absence of activator.

Jan 1, 1977

By Jack O. Jones

The Furnish mine, Caharrus County, W. C., was operated intermittently until 1905 as a gold mine. Scheelite was discovered by A. L. Mash in the mine dumps of the Furniss and Phoenix mines, and he later informed the Bureau of Mines of his discovery. The Bureau of Mines, in two projects at the deposit in 1948 and in drilled 12 holes totaling 1,706.6 feet, examined and sampled the underground workings, excavated by bulldozer and hand, 3,155 linear feet of trenches and collected numerous samples for assay. The best scheelite shown; was found in the underground exposure of the Furniss mine.

Jan 1, 1950

By Earle E. Schumacher, Alexander G. Souden

IN the field of physical metallurgy it is becoming increasingly difficult to keep abreast of the recent develop¬ments since the diversity of investigations is so great and the literature so voluminous. The purpose of this review is to present the more important advances in the nonferrous field during the past few years, the topics discussed being classified broadly as fundamental and practical. The former includes those studies that have done most toward developing the basic science of metals and alloys, and the latter includes technical developments and applications. With the rapid growth of the metal

Jan 1, 1938

By Phillip E. Deering, Robert M. Cox

A model pillar study was conducted in which the engineering principles of dimensional analysis were applied to the problem of coal mine pillar design. The paper reviews the theory of similitude as applied to the model pillar study conducted in the investigation. An example solution of a design problem is included to indicate how the results of the study may be used as a first approximation in the design of coal mine pillars. The design of mine pillars for adequate support with minimum loss of valuable raw materials has always presented a problem to the mining engineer. Most often, for lack of a better method, past practice has influenced the design of new mine pillars. This process has always left doubt as to the safety factor of the pillars. The work presented in this paper is an initial attempt toward adapting the engineering principles of dimensional analysis to the problem of pillar design in underground mines. The use of the dimensional analysis technique is advantageous because all the variables associated with the problem are considered, and by systematic analysis the relative influence of each variable is determined. The model material utilized in this study was taken from the Helena seam of the Cahaba coal field located in central Alabama. The research study was sponsored by The Southern Electric Generating Co. as part of an over-all rock mechanics investigation of the Helena seam area. THEORY OF SIMILITUDE Model analysis is used extensively in engineering today, particularly in the solution of design problems that defy the classical methods of analysis. Such problems arise when materials with a nonlinear stress-strain relationship are involved, when geo- metric boundaries are difficult to define in simple form, when strains become large, or when partial failure occurs. All of these difficulties usually exist in pillar design problems. Those principles which underlie proper design and construction of models, and the interpretation of test results, comprise the theory of similitude. That is, the theory of similitude includes a consideration of the conditions under which the behavior of two separate entities or systems will be similar, and the techniques of accurately predicting behavior of one from observation of the other. The theory of similitude may be developed by dimensional analysis. Dimensional analysis, as a powerful analytical tool, is developed from a consideration of the dimensions in which each of the important quantities involved in a phenomenon is expressed. It is based on two axioms: 1) Absolute numerical equality of quantities may exist only when the quantities are similar qualitatively. 2) The ratio of the magnitudes of two like quantities are dependent on the units used in their measurement, provided that the same units are used for evaluating each. Dimensional analysis, developed from these two axioms, differs from other types of analysis in that it is based solely on the relationships that must exist among the pertinent variables because of their dimensions, rather than on the relationship of natural laws. In itself, dimensional analysis ~rovides qualitative, rather than quantitative relationships, but when it is combined with experimental procedures, it may be made to supply quantitative results and accurate prediction equations. APPLICATION OF THEORY The design of an adequate mine pillar requires the determination of a design equation and the selection of a dimensional system with which to work. Since force plays an important part in the design of mine support, the FLT (force, length, time) system has been used. The factors involved in the dimensional analysis of mine pillars and their dimensions are: A = cross-sectional area L Cp = design strength FL- E, = tangent modulus of elasticity FL

Jan 1, 1969

By L. B. Slichter

Prospecting is certainly the world's biggest and best gambling business. It is a game where the chips cost many thousands and where many millions, even billions, can be won. An attractive feature of this gamble is the fact that the players are free to rig the odds as favorably as possible. Only the limited bounty of nature, the restrictions of the laws of the land, the competition from other players, the limited sagacity of the player himself— only these, and other factors, restrict the possibilities for large winnings. Today probably about half the land surface of the earth remains to be searched for signs of ore visible at the surface. It is fortunate that so much land still remains for exploration by relatively economical methods. Looking to the future, it is a good guess that the costs of finding ore will increase in response to increasing technical difficulties. To continue to achieve profits from prospecting, it will become necessary to analyze the business more skillfully, in a more and more sophisticated manner. Whenever feasible, qualitative concepts must be replaced by their quantitative equivalents, improvements, and extensions. THE GAMBLE The fact that prospecting is a gambling business reminds us at once of the elementary rule known as the law of gambler's ruin. I hesitate to mention so simple a rule in this company of experts. This rule expresses the rather serious chance of going broke when the odds for success are small, merely by a normal run of bad luck regardless of the long-run expectations of gain. The only sure way of avoiding this special risk of gambler's ruin is to have enough capital, and the will, to continue the play many times and thus ride out the inevitable runs of bad luck. For example, if the probability of success is one in ten for each venture, there is a 35 pct chance that ten successive ventures will fail in a row. But if one has the capital to continue the play through a run of 100 failures, then the chance of gambler's ruin is only 5 in 100,000. Almost any management, I suppose, would be under terrific pressure to cease the play during a long run of bad luck. To continue to prospect under such circumstances requires great confidence in the premises, and a firm conviction in the long-term expectation of profit. There is evidence which I shall mention that in the future even the strongest companies may not have the necessary capital to prospect on the ideal scale. Joint ventures will be very desirable as a means for extending the available venture

Jan 1, 1961

By Steve Kral

When the price of gold cracked the US$9.60/g(US$300/oz) mark last year, the gold-mining industry began to crank up again. This followed several years of gold prices that had languished in the mid-200s. Existing mines increased production and mines that had lain dormant for many years were getting second looks. The United States still produces a large amount of gold. But not much of the new production is coming from that country. Instead, strict environmental regulations still have companies wary of trying to invest the millions needed to start a new mine or expand existing ones. And after years of studies and negotiations between legislators, environmental interests and the mining industry, the United States still has not crafted a new mining law.

Jan 1, 2003