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By W. R. Hardwick

This information circular describes mining methods and practices at New Cornelia Branch, Phelps Dodge Corp., Ajo, Ariz. It is one of a series being prepared by the Bureau of Mines on mining methods, practices, and costs in various mining districts of the United States. The New Cornelia mine (fig. 1) is at Ajo, a town in southwestern Arizona (fig. 2) on Arizona State Highway 85 in the western part of Pima County. The [oncentrator] and smelter are near the mine (fig. 3). Copper ore is mined, crushed, ground, and concentrated, and the concentrates are smelted. Copper is cast in anode form and sent to the Phelps Dodge Corp. refinery in El Paso, Tex.

Jan 1, 1960

By A. Ignatieff

"Excavation, the principal mining process, 'which hitherto has been based largely on the intuition and logic of mining men, is increasingly receiving the attention of engineers and scientists versed in rock mechanics. The paper intro-duce the principles of this science in simplified form, directed both to underground and open-pit mining. Reference is made to the large annual tonnage from ore and rock excavations, which in 1967 were responsible for 250 million tons of mineral production in Canada.The urge to transform excavation into a continuous instead of an interrupted process is discussed with references to the various types of energies employed or proposed in rock breakage or excavation. Due to the rapid decay of applied energy in the discontinuous and heterogeneous rock environment, large confined blasts proposed for in-situ mining do not give much expectation of success as yet. Raises and ventilating shafts are already bored in reasonably hard rock. Tunnelling machines will be used for drifting and cross-cutting in the future, but continuous mining machines of the cuttmg and shearing type are not 'around the corner' for stoping typical orebodies. On the other hand, bed mining, particularly of coal, has led the way in continuous mining, and Remotely Operated Long-wall Face (ROLF) experiments are progressing in an encouraging way. Some reflections on the mining environment in relation to the human element are made."

Jan 1, 1970

Used in conjunction with geology and geophysics, geochemistry provides powerful exploration tools of special relevance to Australian environments. New methods are needed that will confront the forthcoming emphasis on locating concealed orebodies. Deep weathering is conducive to techniques using groundwaters or gaseous emanations as sample media. Increasing use is anticipated for isotope measurements and for recognition of country rock characteristics that denote proximity to mineralization. Improvements in the sensitivity, reliability and portability of analytical instruments will underpin the contributions of geochemical methods to future mineral exploration.

Jan 1, 1982

By Roland B. Hoag, Roger G. Webber

Sulphate concentration in groundwater is a good measure of the extent of oxidation of sulphides, provided that sulphide minerals are the primary source of the sulphate. A study was conducted near the Eustis Mine in Quebec to determine where and how the sulphate in groundwaters originated. Atmospheric precipitation is the only source of sulphate other than oxidation of sulphides, and in this study area it is equal to 0.01,. millimole per litre. The oxidation of sulphides can be divided into subsurface oxidation (mainly inorganic processes) and surface oxidation (including both organic and inorganic processes) . The maximum sulphate concentration due to subsurface oxidation of sulphides depends on the solubility of 0 2 in water and is 0.25 millimole per litre. Surface oxidation is, therefore, responsible for any amount greater than atmospheric plus subsurface contributions (0.29 millimole per litre). Surface inorganic oxidation occurs in waters with a pH greater than 15 and is controlled by the kinetics of the oxidation processes. Organic (bacterial) surface oxidation is dominant only in acid (pH< 1.5) waters. The bacterial action accelerates the oxidation of sulphides, and large quanttties of sulphate may be introduced into solution.

Jan 1, 1976

By M. Muinonen, R. Pandher

Royal Nickel Corporation is developing the Dumont Nickel Project, a large nickel sulphide deposit located near the town of Amos, Québec. The nickel occurs as pentlandite, heazlewoodite, and awaruite. The relatively low grade ore can be processed to a very high grade nickel concentrate, containing 29% Ni. The absence of copper and precious metals in the ore renders this concentrate amenable to processing by dead roasting in a fluid-bed roaster and smelting in an electric furnace to produce ferronickel for sale to stainless steel producers. Laboratory test work and conceptual engineering design was completed to demonstrate the amenability of Dumont concentrate to produce ferro-nickel.

Jan 1, 2015

By Alastair C. Torrance

"A brief review of the Australian mining industry is given followed by a more detailed treatment of a study of the influence of primer Size on explosive performance. This is based on a joint research programme conducted by BHP Central Research Laboratories and Dyno Wesfarmers Ltd and examined the effect of the size of cast primers on the run up and steady state detonation velocitiesof ammonium nitrate based explosives as a function of blasthole diameter. The field trials examined a numter of the Dynamo 'Westfarmers HDF series of primers in conjunction with ANFO, emulsion and watergel explosives. Results indicate that the iun up velocity of 187 mm diameter ANFO charges is negligible using cast primers as small as 150g. However, emulsion and watergel explosives did exhibit run up in both 187 and 3:1mm diameter blastholes, independent of the size of primer. This could last from 7 to 10 blashole diameters"

Jan 1, 1991

"ALTHOUGH Canadian metallurgists have long been active in research, the scope of the work was somewhat limited until the be-ginning -of World War II. The rapid industrial development of Canada during the past ten years has been accompanied by .a similar upsurge in research. However, the wide geographical distribution of the research centres has made it difficult for the individual research workers to meet together and to exchange ideas or even to learn what projects .are being investigated or the nature and extent of the facilities available for work of this kind.The purpose of the present symposium is to assemble data relating to projects under investigation and the facilities employed at the various metallurgical research laboratories in Canada, thus providing some measure of correlation so that workers in different locations may learn what kind of work •is being .done at other points throughout the country.In reporting the symposium it has not been possible to reproduce the papers in full, but excerpts have been selected that give the essentia1 data."

Jan 1, 1952

By Jr. Flynn

This U.S. Bureau of Mines publication is a compilation of fundamental cyanide chemistry data obtained through review of the scientific literature. It includes information on thermodynamics and chemical equilibria, ultraviolet-visible and infrared spectra, and the chemistry and photochemistry of cyanide, chemical species derived from cyanide, and metal cyanide species. It also includes guidance on the use of the data for solving practical problems in precious metals applications. This publication is intended mainly for use as a reference by personnel in the precious metals industry and regulatory agencies, and other cyanide users, to provide comprehensive information on cyanide chemistry. The document should assist in the formulation of effective policies for cyanide control in the construction, operation, and closure phases of precious metals mining and metallurgical operations. In addition, the data in this publication will be useful in other contexts, such as dealing with industrial cyanide usage, cyanide-containing wastes and associated environmental problems.

Jan 1, 1995

By Q. Cheng

This paper introduces the multi fractal interpolation method (MIM)developed for handling singularities in data analysis and for data interpolation. The MIM is a new moving average model for spatial mapping and interpolation. The model decomposes the raw data into two components: singular and nonsingular components. The former can be characterized by a localized singularity index that quantifies the scaling invariance property of measures from a multifractal point of view. The latter is a smooth component that can be estimated using ordinary kriging or other moving average models. The local singularity index characterizes the concave/convex properties of the neighbourhood values. The paper utilizes a binomial multiplicative cascade model todemonstrate the generation of one- and two-dimensional data with multi-scale singularities which can be modelled by asymmetrical multifractal distribution. It then introduces a generalized moving average mathematical model for analysing and interpolating data with singularities. Finally, it is demonstrated by a one-dimensional case study of de Wijs’ data from a profile in a zinc mine, that incorporation of spatial association and singularity can improve the interpolation result, especially for observed values with significant singularities.

Jan 1, 2015

By Benjamin Cebrian

Traditional dilution control systems range from computer modeling, use of physical markers on the field as polypipes to a technology that marks some control points where displacement is measured. The latter includes walking over a muckpile which is prohibited by some mining companies as a safety measure. The new technology presented in this paper is a patented system that is installed on board excavators (backhoe or front shovel types). Several control points are set along ore/waste contacts and their position is uploaded on the corresponding shovel. The operator proceeds on mucking until he is alerted when reaching any of the several control points previously located in the blast patterns and that have moved with the muckpile. A case study is presented at a high grade copper mine, were unique 3D shapes are showing as a result of using an on-board excavator dilution control system. Both ore-loss or dilution cost of opportunities are analyzed.

By Gregory A. Johnson

Operations and Maintenance departments have long had an adversarial relationship. The widespread evolution and adoption of modern management techniques such as Reliability Centered Maintenance (RCM) and Lean Production however has driven interest in working co-operatively to optimize overall plant performance. Mining and minerals operations have long adopted RCM in maintenance, and are now adopting Lean throughout the organization. Modern management initiatives like these explicitly call for co-operation between the two disciplines of maintenance and production and many advances have been made in the realms of people and methodology. One area that has lagged behind in supporting these developments however is information systems. Enterprise Asset Management (EAM) systems in maintenance and newer Manufacturing Execution Systems (MES) in operations have not been truly integrated in the way needed. Complicated plants, different software architectures, continually changing conditions and many variables have lead to systems problems which have contributed to the maintenance/operations divide. Master data synchronization (the ?plant tree?) and integrated reporting of real-time data with transactional data are just two of the issues that are being solved by new approaches in information technology including web services and service orientated architectures. New technologies are coming on-stream to enable the final ?bridging of the gap?.

Feb 1, 2008

By K. Oraee

A comprehensive, harmonic and sustainable development has always been a real concern of state policy makers. To reach such development, regional planning is an approach which is widely applied. This paper deals with policies adopted by a given country with rich mineral deposits, in order to accomplish a mining growth as well as economic development in relatively poor regions. In this regards, first, some worldwide experiences belonging to China, with large scale mining operations and Nigeria with a small scale mining industry, are studied. The mining industry in Iran is then considered as a case study. The study continues by categorizing and prioritizing Iranian regions based on their mining potential and the degree of development, using statistical analysis and Taxonomy and AHP techniques. Results obtained serve to provide recommendations as to where capital investments in the mining industry would produce highest returns. The approach used, together with the practical policies suggested in this paper, can be used to adapt appropriate strategies for mining development in a way that contributes to regional development and a more effective income distribution.

Jan 1, 2012

By Dale Preece, C. Mick Lownds

Detonation delay timing has been an important aspect of quality rock blasting for decades. Detonators that enable delay timing have improved over the years especially with the recent advent of precision electronic detonators. The positive effects of precision delay timing have been observed repeatedly in the field with improved fragmentation, heave and overall blast control.

Jan 1, 2008

By H. A. Bilgin, G. G. U. Aldas

"Ground vibration is the natural result of the blasting process. Many empirical formulae and methodologies including analysis of travel path effects have been developed. The scaled distance, which is the most popular approach for the calculation of the attenuation of particle velocity in the ground, has led to significant advances in the prediction of particle velocity when both explosive charge and distance vary. However, this approach does not consider the effect of ground anisotropy and existence of structural geological features on ground vibration. Therefore, in this study, the effects of these rock mass properties on types, amplitudes, and frequencies of ground vibration waves at four surface mines are examined. The results, which were implemented at Kangal coal mine, Bastas quarry and Kíbrís quarry, provided guidance for the extensive study at Orhaneli surface coal mine.As a result of the study, the authors came to the conclusion that vibration amplitudes change depending on the ground on which sensors were deployed and the conditions depending on whether measurements were done near major structural geological features. It was determined that the vibration amplitudes, measured at equal distances from the source but in different directions, change because of the propagation velocity anisotropy. Besides the change of wave type due to the kind of ground at the measurement location, it was determined that vibration anomolies were due to structural features."

Jan 1, 2004

The State of New South Wales is highly favoured in having vast deposits of coal adjacent to and within easy reach of the coastal Ports. Not only is the quality of the fuel generally superior to any found in the other States, but it is greater in extent than in any other part of the Continent. For interesting and reliable details of the history of the discovery of coal, the geology of the coal bearing strata, analysis of the various coals and other valuable data, the readers are referred to the book recently issued by the New South Wales Government, entitled The Mineral Resources of New South Wales, by Edward F. Pittman, A.R.S.M., etc., by the direction of the Hon. T. L. Fegan, Minister for Mines. The mining community is indebted to the Minister for having had published the most valuable condensed record of the mineral resources of the State extant.For the purposes of this paper we will only give such a general description of the coal fields as will make it intelligible in connection with the subject of the coal mining in the State of New South Wales.

Jan 1, 1904

By S. Shi, J. Y. Hwang, B. Li

Silver, copper, and zinc are commonly known elements with antibacterial and antifungal capabilities. Attempts have been made to dope silver on minerals, glass, and ceramics and the resulting materials have been investigated for their antibacterial and antifungal properties. Since silver is expensive and very reactive, silver doped materials have been found inappropriate in some applications. Copper-vermiculite is investigated as an alternative. Vermiculite has high cation exchange capacity on the magnesium ion in the crystal structure. Copper ion may have a high tendency to replace magnesium because of similar charge interference and ionic radius. Copper-vermiculite is prepared by reacting vermiculite and copper chloride solution. By impregnating copper ions into the nanometer openings between the layers of vermiculite, it is possible to render the composite with antibacterial functions if the copper ions could be released gradually from the composite. The antibacterial efficiency of Cu-vermiculite against Escherichia coli was studied using the Halo method. The results show that Cu-vermiculite is effective for preventing the reproduction of the bacteria. Heat treatment of Cu-vermiculite at up to 400°C does not show significant changes in antibacterial activities.

Jan 1, 2002

By McLean E. J

Background The resources of the Gippsland Basin include not only the coal and oil for which it is well known, but also the tourism resource and the quality of life which it offers its residents and visitors. To manage this group of resources requires an understanding and ability to predict the consequences of possible developments. The water of the streams and estuaries as a key component as it is both a resource and the means for transporting wastes from one area to another. To aid in the resource planning process there is a need for models of the estuarine hydraulic processes. This paper describes an appropriate modelling technique. Resource use conflicts may arise from developments in the catchment upstream of the estuarine reach. For example the diversion of water for domestic and industrial use will change the velocity and salinity structure of the downstream estuary. In turn these changes will affect sediment distribution and deposition patterns and may impose stress on the biological communities and ultimately on the fisheries resources and water quality. The manager of an estuarine system may have expertise in ecology, hydraulics or another of the specialist disciplines involved, but commonly will not. The manager will identify needs for resource and development and the broad options required to satisfy them. The manager will use these studies as the basis for his/her selection of the option for execution. Thus a model for&apos;use by the manager of an estuarine system must have the following properties: (i) The model must be sufficiently accurate to throw up all the likely options. (ii) The model must be capable of being run by the manager, interactively, to answer `what if&apos; questions. This requirement implies a simple code andhardware limited to a personal computer or possibly a desk top work station. (iii) The model must be robust so that unrealistic input oes not generate apparently useful output, and no output is generated for cases where the model is not designed to give results. (iv) The model must be capable of being used as part of a modelling system comprising models of all the geographic and demographic components

Jan 1, 1992

By Kay E. Goldberg

The Bureau of Mines conducted a study to develop and evaluate a training workshop for mine safety training personnel. The workshop was based on the Instructional Development Institute (IDI) which has been used for nearly ten years to train educators and administrators in the application of a nine-step model for defining, developing, and evaluating instruction. The Mining Instructional Development Institute (MIDI) was developed by investigators at the University of Southern California as a two-phase project. Phase I involved the modification of the six-day IDI program (including audiovisual presentations, workbooks, games, and exercises) for use by mine safety trainers as a workshop lasting three and one-half days. Phase II involved the evaluation and validation of the prototype MIDI workshop by means of a two-stage jury of experts and a prototype field trial. On the basis of data collected in the validation process it was determined that the institute provided an effective and useful method of instruction in mine safety training and that the institute would be especially valuable for mine safety training administrators and supervisors.

Jan 1, 1980

By Shigeru Nishitake

The Earth Pressure Balanced (EPB) shields designed by Mitsubishi Heavy Industries, Ltd., are recently more enthusiastically accepted by tunnel boring specialists. This company having built 1,000 tunnel shields utilizes its vast experience to resolve the problem to excavate through big boulders scattered in rather soft alluvial soil. Several types of EPB shields which can cope with large size boulders are described. Such shields are equipped with both drag bits and rolling disc cutters on the cutterheads. Previously removal of boulders has presented safety problems for workers while in the muck chamber, or venturing in front of the shield. This report describes the problem and how the equipment was modified to deal with the problem.

Jan 1, 1987

By M. Sibanda

The diffusion of carbon in Co-5% Fe alloy was studied in a belt-type pressure system at temperatures of up to 1330°C and press loads or nominal pressures of 7 020 tons or 42±3 kbar. Under these conditions, this alloy is in the solid state. Discs of graphite and prealloyed Co-5%Fe were used to make up the diffusion couple. The diffusion coefficient increased with increasing press load due to the tendency of the low density graphite to dissolve in the metallic phase reducing the overall volume and increasing the density of the system. Furthermore, inhomogeneous plastic deformation may have promoted diffusion by creating defects in the alloy. Diffusion couples treated at atmospheric pressure exhibited graphite particles in the metal, while those treated at high pressures exhibited carbide in the form of Widmanstatten laths. Carbon analyses indicated increased carbon solubility with increasing pressure. This was confirmed from calculated high-pressure phase diagrams.

Jan 1, 2005