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IN 1906, soon after his arrival in New Zealand, a brief article was prepared by the writer on "The Salient Features of the Economic Geology of New Zealand," for the Journal of Economic Geology. In November, 1907, a somewhat similar paper, entitled "The Mineral Wealth of New Zealand," was read at the Royal Colonial Institute in London. The present contribution to the Transactions...

Jan 1, 1909

By T. J. Haddon

For the mining industry in general and gold mining in particular the past few years have been difficult. Economic conditions coupled with growing regulatory restrictions have led to increasingly important reasons for managing assets wisely. From a public company perspective this makes sense because it ultimately provides for an increase in shareholder wealth and that's what we're in business to do. Regardless of whether a company is public or not, assets must be managed effectively to remain a player in today's competitive environment. So, as the CEO of a gold mining company, how do we manage our assets to ensure that we are satisfying our obligations to our customer --the Amax: Gold shareholder? Let me tell you. As I said earlier, the gold industry has been under siege. We have just completed our third year of average prices below $400 per ounce. When you add finding and/ or acquisition costs and development costs to operating costs, there isn't much of a profit margin left. What this environment provides, however, is opportunities for growth. In the gold business, you either grow or you die. Today, most North American gold producers have at most a 10 year mine life. We are all scrambling to add reserves so we don't become extinct. As prices remain low, opportunities for increasing diminishing reserves abound. This is the time for the opportunistic company to take advantages of market conditions and that's precisely what we, at Amax: Gold, have done!

Jan 1, 1992

By John Ramsay, Frederick A. Edwards, J. Eric Belford, Clarence V. Amyotte

"DEVELOPMENT of the underground mine is carried out from a main ramp driven from surface to the 800 and 1200 levels and from a shaft sunk to 3050 ft. Sub-levels at approximately 100-ft vertical intervals, starting 300 ft above the 800 level, were collared from the ramp as it advanced and a considerable amount of development work was pursued. The lateral and ramp work provided an opportunity to train drift crews, test equipment and methods, assess ground conditions and advance the initial stope development. The development of an exhaust ventilation raise system closely followed the extension of the level development to the south end of the orebody (Fig. 26) . On completion of the shaft, temporary lip pockets were installed at the shaft stations on the 800, 12.00, 1600, 2000 and 2400 levels. The permanent loading pocket had been installed on the 2860 level as part of the shaft-sinking contract and the level had been connected to the 2800-level station by a small muck transfer raise. Development of the 2800-level area was given top priority at this stage. This included a 1000-ft cross-cut to the crusher location, the crusher excavation, storage bins, conveyor ways and a ramp to connect the 2800 level to the loading pocket, the rope changing station and the shaft sump. The development and installation of the rock handling system between the 2400 level and the shaft bottom was contracted to Macisaac Mining and Tunnelling Company, of Sudbury, Ontario."

Jan 1, 1974

By Lee Ann Gardner

This U.S. Bureau of Mines publication presents a case study of the processes used in permitting the Nome Offshore Placer Project, a gold mining project offshore Nome, Alaska which operated from 1985 through 1990. The mining project, developed by Western Gold Exploration and Mining Company, Limited Partnership (WestGold), used the BIMA, which was at the time the largest bucketline mining vessel in the world, to dredge gold from the ocean floor. This case study reviews the permitting process from the regulators' and industry's perspectives, as well as characterizing the efficiencies and inefficiencies associated with this case. The Federal, State and local laws applicable to the Nome Offshore Placer Project are identified, agency jurisdiction and interagency relationships are explored, and the chronology of the permitting process is examined. The regulatory authorities for both environmental monitoring and post-mining monitoring are delineated. Significant milestones affecting the project and required regulatory submittals are also included. The case study of the Nome Offshore Placer Project is detailed with respect to agency involvement and coordination, approaches to permitting from both the regulators' and developer's perspective, environmental issues, and permit stipulations which were unique to the project. The advantages and disadvantages of these topics are discussed.

Jan 1, 1992

By A. C. Fieldner

"Gas hazards may be divided into two principal classes- namely (1) inflammation and explosions; (2) asphyxiation and poisoning. Inflammation and explosion are prevented first by adequate ventilation so that gas sufficient to propagate flame or explosion can not accumulate, and second, by avoiding sources of ignition such as open lights, flames, sparks, electrical arcs, short circuits, or sparks. Ventilation is also the best preventive measure against asphyxiation and poisoning from toxic gases. When men must enter unventilated or poorly ventilated places containing poisonous or asphyxiating gases, suitable gas masks, hose masks, or oxygen breathing apparatus should be worn. As a rule, loss of life and property from gas hazards is due to ignorance of the properties and hazards of various gases commonly used, and consequently a failure to use proper measures for eliminating and meeting these dangers. It is the purpose of this paper to describe briefly the common gases and vapors with respect to the hazards involved in their use and to discuss the necessary precautions and methods for avoiding these dangersLight, heat, and power are prime essentials of our modern industrial civilization. The combustible gases and vapors used for the production of these necessary elements of our existence comprise the largest and most common group of domestic and industrial gas hazards. Almost every individual in his daily life subject to possible danger from asphyxiation, fire, or explosion due to one or more of these gases. For evidence one need only refer to the daily newspaper where headlines such as the following are frequently seen; ""Family asphyxiated by carbon monoxide from gas heater;"" ""Schoolhouse wrecked by gas explosion in basement;"" ""Man killed by automobile exhaust fumes in his garage;"" ""Fireman overcome by smoke fumes in basement ""Woman"".""Boman severely burned by accidental ignition of gasoline used in cleaning gloves;"" and 'in recent Years we often see ""Building wrecked by explosion of still in residential district.""It will be noted that these accidents are due to inflammation, explosion, or asphyxiation. Any combustible gas or vapor, when mixed, with air or oxygen within certain limiting proportions, will explode on ignition. The violence of the explosion varies with respective proportions of air and gas, and with the degree of confinement of the mixture. For example: Mixtures of natural gas and air containing between 4.5 and 12 per cent natural gas will explode, or propagate flame throughout the mixture without the continual presence of the source of ignition that started the inflammation. The table following gives the explosive limits of the common combustible gases and air:"

Jun 1, 1926

By J. R. Menasce

Mechanization in low-stope panels situated in hard rock infers roof support by tensile bolting to allow free passage of trackless mining equipment in the production areas. This is in sharp contrast to conventional mining, where compressive roof supports?such as timber and grout packs?have traditionally been used, up to 1.5 metres from the production face. Bolting is a hazardous operation because material is dislodged from the roof during the drilling activity. Even with temporary roof support installed, small pieces of rock are dislodged by the percussive action of the drifter. Operations with the man situated directly under the drill, during the drilling activity, are hazardous. The only way to remove the hazard is to move the man away from the machine for as much as possible throughout the complete cycle Costs associated with safety cannot be quantified, but need to form part of the decision-making process. Machine selections based on purchase and running costs alone do not justify the investment cost of mechanized bolters. The equipment selection process needs to take into account the total cost of mining as well as the human safety impact and loss of production costs from having to re-bolt roofs in a production panel to prevent falls of ground. Labour costs in mechanized low-stope bolting are between one-quarter and half the labour costs of non-mechanized bolting. This paper reviews the mechanized bolting option versus handheld bolting from a mining process and cost perspective in a hard rock, low-stope room-and-pillar mining operation in the platinum and chrome industries.

Jan 1, 2006

By P. Conrad

Experience has shown that, since the passage of the Surface Mining Control and Reclamation Act, over-compaction of spoil during the reclamation process has severely limited tree growth on reclaimed land. Researchers at the University of Kentucky have conducted a ten-year investigation at a surface mine in eastern Kentucky that monitored the changes in selected spoil physical characteristics for various reclamation and compaction alleviation methods. More specifically, research plots were developed for reforestation that employed three different levels of compaction and two different methods of ripping for overly compacted spoil. Each year measurements were made in the field of dry bulk density, using a nuclear density gage, and maximum penetration depth, using a recording cone penetrometer. In addition to good correlation between tree growth and selected spoil characteristics, the data demonstrated a gradual convergence of the measured spoil characteristic data over the study period.

Jan 1, 2008

By D. W. Lui

Tangdan copper oxide deposit, the largest independent copper oxide deposit in China so far, is located in the northeast of Yunnan province, southwest of China. The ore from this deposit is characterized by: low grade, high oxidation ratio, and fine-grained disseminated, resulting in poor flotation recovery. The analysis of plant flotation data reveals that the loss of copper minerals into tailings is mainly with coarse size fraction due to insufficient liberation and fine size fractions, especially minus 10 microns fraction, which proved to be very difficult-to-float with conventional flotation. In order to improve the performances of plant flotation of this ore, laboratory flotation tests were conducted with the pure malachite, which was the principle copper oxide mineral in Tangdan copper ore deposit. The results obtained suggested that a finer grinding (up to -325 mesh or even -400 mesh) be needed to decrease the loss with coarse size fraction, and vacuum flotation is a promising way for the recovery of the fine malachite effectively.

Jan 1, 2014

By Forrest T. Moyer

The safety record of the metal mining and milling industries in 1965 is reviewed by the Bureau of Mines. The overall injury-frequency rate of 23.77 per million man-hours was 5 percent lower than in 1964 and was the lowest annual rate in a statistical history beginning with 1931. The injury-severity rate of 3,521 days lost per million man-hours in 1965 represented a 5-percent improvement over 1964. However, the total of 3,825 disabling work injuries comprised 61 fatal and 3,764 nonfatal injuries, one and 92 more, respectively, than in 1964. At primary nonferrous smelters, refineries, and reduction plants, the injury-frequency rate of 8.97 per million man-hours in 1965 was 13 percent lower, but the severity rate percent higher than in 1964. these plants in 1965, 4 more of 1,173 days lost per million man-hours was 17 There were 12 fatal and 971 nonfatal injuries at and 28 fewer, respectively, than in 1964.

Jan 1, 1969

By M. L. Harris

Coal dust produced during the mining process is a prime explosion hazard in underground coal mines. To inert the coal dust and prevent a catastrophic propagating dust explosion, rock dust is applied to the roof, ribs, and floor surfaces of mine entries. Currently, one determination of whether a mine is adequately protected from the coal dust explosion hazard is made by analyzing collected mine dust samples for percent total incombustible content (% TIC). A minimum of 80% TIC is required per 30 CFR 75.403. The as-received moisture of the dust sample is included in the % TIC. Moisture and humidity within a coal mine vary greatly with the seasons, with explosions occurring more frequently during dry winter months. This paper will discuss the fluctuations of the as-received moisture content of the mine dust samples collected by U.S. Mine Safety and Health Administration inspectors in 2010 and the observed fluctuations of the moisture content of rock dust within the U.S. National Institute for Occupational Safety and Health Office of Mining Safety and Health Research Bruceton Experimental Mine and the Safety Research Coal Mine over a one-year period.

By Stephen C. Tadolini

Effective barrier pillar design is an essential component for safe and productive underground coal mining. Barrier pillar design methodologies that incorporate sound engineering judgment have been used for practical everyday usage. The next logical step is to utilize numerical modeling techniques that help combine practical experience and empirical observations into barrier pillar design analysis. A case study is presented that describes the barrier pillar design process, but also highlights the importance of considering the global mine response by evaluating: adjacent pillar stabilities, impact of intersection and entry widths, capacity of primary and secondary bolting systems and rib stabilization used for the safe and efficient removal of the longwall face equipment.

Jan 1, 2013

By J. Spotts McDowell

Ackowledgments........................... 5 Introduction............................. 5 The Silica Minerals. Stability Relations......................... 6 Optical Properties........................ 9 Density.............................. 10 Melting Points....;..................... 10 Thermal Expansion..................,..... 10 Solubilities............................ 12 Identification of Cristobalite and Tridymite.............. 12. The Silica Refractories. Raw Materia1........................... 13 American Deposits....................... 13 Properties Determining Usability................ 15 Expansion on Heating..................... 16 Texture........................... 17 Silica Brick............................ 17 Manufacture........................... 18 Properties of Silica Brick .................... 19 Analysis ......................... 19 Density......................... 19 Porosity......................... 20 Strength....................... 21 Melting Point....................... 22 Specific Heat....................... 22 Thermal Conductivity................... 23 Expansion........................ 24 Effect of Rapid Temperature Change.........:... 26 Constitution......................... 26

Jan 1, 1918

By Ivan Simon, R. K. McConnell

Anticipating the availability of tiltmeters suitable for use in boreholes, this article proposes a method of using one or more of these meters to determine in situ stress distribution before and after mining operations. Several ways of using relief techniques to measure in situ stresses in rocks have been developed. These techniques, summarized by Merrill,1 involve measuring deformations which take place when a specimen of rock is wholly or partially isolated from the stress field in the surrounding rock. Measurements of rock deformation caused by stress relief from mining operations can, in principle, also be used to estimate in situ stress distributions. Müller2 has mentioned experiments being carried on in Austria with a "deformation indicator" to determine the tilting of holes drilled before a mine opening is made. Similar work using borehole extensometers has been reported by Potts? and Duvall4 has called attention to the possible use of tiltmeters in making these measurements. Considerable attention is now being paid to the use of tiltmeters in detecting rock deformation associated with fault movements, earthquakes, earth tides, etc. The instruments used for these measurements have usually been of the mercury tube, water tube, or quartz fiber type, but because of their large size, and/or fragile nature, such instruments would not be suitable for use in mining stress measurements. Recent instrumentation developments, however, give promise that rugged, sensitive tiltmeters small enough for use in boreholes may soon be available.' In anticipation of these developments, this article presents a number of calculations of the possibility of using one or more tiltmeters emplaced in a drill hole prior to mining operations to determine the in situ stress distribution both before and after a mining operation. Consider point p (x, z) near a tunnel of radius a

Jan 1, 1969

By I. J. Duckworth

During the last twenty years computers have be-come widely used to assist with the simulation and design of large scale, primary ventilation systems. However, to date there are few computer programs available to help with the modeling of auxiliary ventilation in dead-end headings or tunnels. This paper presents the results of the first year of a research and programming study dedicated to the development of a user-friendly duct simulation tool. Included is a literature review that summarises publications on duct leakage and resistance, on previous programs developed for the simulation of airflow in ducts, and case studies on extended ductlines in mines and tunnels. The methodology behind the development of Ductsim, a Windows based simulation program is presented.

Jan 1, 2000

By Frances H. Clark

IN a concern with the varied interests of the Western Union Telegraph Co., where practically all types of metals, both ferrous and nonferrous, are utilized, many types of failures of materials occur. These have to do not only with outside plant construction, such as corrosion and fatigue of line wire and cable, but also with inside plant equipment operating at such high speeds that rapid deterioration of metal. parts due to fatigue and wear results. Both corrosion and fatigue affect the life of copper wire so its normal life in any particular locality is largely dependent on the atmospheric conditions. Tensions vary widely owing to changes in temperature and ice and wind loadings and the wire is Subject to a great range of vibration caused by wind gusts aril vibration front trains or other heavy vehicles transmitted through the earth. High frequency low-amplitude vibrations are sometimes audible as singing in the wire. The other extreme is the vertical slashing or dancing of the wire observed during severe storms where amplitudes of 9, ft. or more at low frequencies have been observed.

Jan 1, 1942

By Ward M

The current and future requirements for an underground mine information management system are being met with a flexible, value-engineered approach to mine information/communication infrastructures. El-Equip has developed and delivered to over fifty mines around the world an integrated, high capacity, radio-based leaky feeder communication system called MultiCOM. To meet the requirements of recently developed advanced information management technologies, such as production and ventilation management, the system has evolved to support simultaneous mobile and fixed information delivery services over an integrated single cable system. The following paper will review how MultiCOM is enabling information/communications technology to cost-effectively implement mine monitoring and control applications. Applications described in this paper include mobile vehicle production tracking, vehicle location, ventilation system monitoring and control with integrated ventilation system simulation. The techniques described are leading the world in terms of flexible and value-engineered applications of technology in the underground mine.

Jan 1, 1995

By Felicia F. Peng

The manganese removal from aqueous solution containing high Mn2+ concentration by adsorption and oxidation was studied using manganese oxide particles as the adsorbent. The operating parameters including pH, flow rate, initial manganese concentrations, and oxidant dosage affect the performance of Mn2+ removal were evaluated in a laboratory packed column. In the multi-column adsorption tests, each additional column doubled the time for complete manganese removal. No further decrease of pH was also observed once it was lowered to pH 4.5 to 5. This finding implied the possibility of complete high manganese removal without further pH adjustment during adsorption. Oxidation of Mn2+ by dissolved oxygen was found to be insignificant for manganese removal for high Mn2+ concentration. Adsorption was the predominated mechanism involved with manganese removal. Extremely low H+/Mn2+ stoichiometry compared to the reported values was measured. These low values suggested that different adsorption mechanisms such as chemisorption other than H+/Mn2+ ion exchange might play an important role at low pH. This paper presents the quantity and explanation of the results obtained for the mechanism of adsorption and oxidation of high concentration manganese on the manganese ore particles.

Jan 1, 1997

By J. B. Newson

This is one of a series of circulars dealing with mining methods, practices, and costs. It describes the method of sinking a shaft 60 inches in diameter with a shot drill, as employed at the Idaho Maryland mine, Grass Valley, Calif. The operation involved a great deal of experimentation in applying the shot-drill method to large bore drilling, overcoming mechanical and other difficulties which developed during sinking, and developing operating technique. Under such circumstances, costs are obviously higher than they would be after the pioneer work has been done, but even so, these actually obtained compare favorably with costs of sinking by more conventional methods. ACKNOWLEDGMENTS The authors are indebted to Mr. Errol McBoyle, president of the Idaho Maryland Mining Co., not only for his cooperation and advice during the sinking of this experimental shaft, but for permission to prepare this article for publication with the inclusion of cost data.

Jan 1, 1936

Advances in Coarse Particle Recovery - Fluidised-Bed Flotation

Sep 13, 2010

1. Book review Assay and analytical practice in the South African mining industry, byW.C. Lenahan and R. de L. Muray- Smith. Johannesburg, The South African Institute of Mining and Metalurgy, 1986. RlOO (R80 to Members). Reviewer: N.G. Randolph 2. Canadian publications A market profile for industrial minerals in Canadian manufacturing sectors, by M. Prud'homme and D. Francis. 1987. Micromedia Limited (144 Front Street, Toronto, M5J 1G2, Canada).The following three publications are available from the Centre for Resource Studies, Queen's University, Kingston, Ontario, Canada K7L 3N6. An analysis of Japanese coking coal procurement policies: The Canadian and Australian experience, by D.L. Anderson. Feb. 1987. $25. Technology policies in the Canadian mineral industry, edited by M.J. Wojciechowski. Sep. 1986. $20.Value-added taxation: Issues and impact for Canadian mines, by B.l. Dyack. Nov. 1986. $7.3. Mintek reports Report M295 A mineralogical investigation of refractory gold ores and their beneficiation, by P.M. Swash. Report M296 The determination, by distilation-spectrophotometry, of chlorine in apatite-type materials containing fluorine, by M. Solomons. Report M297 The interference of zirconium in atomic-emission spectroscopy using inductively coupled plasma, by P.l. Wright.

Jan 1, 1987