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By D N. B Skinner, M P. Simpson

At Ohio Creek, 3 km northwest of the Thames bonanza goldfield, porphyry Cu-Au mineralisation is hosted in a dacite porphyry associated with porphyry intrusion breccias and overlying andesites and dacites. The geological setting is a Jurassic greywacke basement overlain by Late Miocene andesite-dacite volcanics which are extensively altered to propylitic and argillic assemblages. Diamond drilling at Ohio Creek in 1978-1981 by Amoco Minerals intersected low grade Cu-Au (0.12-0.20% C~ 0.23-0.4 glt Au) mineralisation An advanced argillic 'alteration cap containing quartz-alunite¦dickite or pyrophyllite-dickite¦diaspore is centred on the adjacent Lookout Rocks and has potential for high sulfidation Au-Cu mineralisation. There is a zonation from potassic K-feldspar-magnetitealteration at depth in the dacite porphyry, through an overlying phyllic quartzsericite- pyrite zone which is overprinted by pyrophyllite in the overlying advanced argillic cap. Early quartz stockwork veinlets associated with the potassic alteration contain fluid inclusions that trapped a highly saline (50-80 wt% NaCI equiv) fluid at high temperatures (450 to >600¦C) indicative of a magmatic fluid. Some chalcopyrite is associated with slightly later quartz-magnetite veinlets, but the bulk of the copper occurs as disseminated chalcopyrite associated with the phyllic alteration. The potassic alteration is surrounded and overprinted by propylitic chlorite¦epidote alteration. Late polymetallic sulfide-quartz-anhydrite veins occur within and around the margins of the porphyry system as in the Kaiser Reef. Fluid inclusions associated with these late veins were formed at temperatures of about 250-320¦C from low salinity (1-3 wfl~ NaCI equiv) fluids. The spatial association between porphyry eu-Au mineralisation, advanced argillic alteration and polymetallic sulfide veins suggests that they are genetically part of the same hydrothennal system. This is consistent with reconnaissanceK-Ar dates of 11.6-10.7 Ma for the intrusive porphyry at Ohio Creek, alunite in the advanced argillic alteration zone at Lookout Rocks and sericite selvedges from the Waiotahi gold-quartz veins at Thames.

Jan 1, 1998

By Kleidon Rodrigues de Almeida

O presente projeto descreve um trabalho de otimização dos ensaios laboratoriais de liberação do produto para fins elétricos na CSN (Companhia Siderúrgica Nacional), sendo tema de um projeto Lean Six Sigma. O foco do projeto foi otimizar os ensaios de epstein, tração e dureza, reduzindo o Lead Time de liberação dos produtos para fins elétricos e a quantidade de ensaios realizados. Para a realização deste trabalho, fez-se o uso de ferramentas e métodos Lean Six Sigma, permitindo a busca dos resultados de maneira sistêmica, superando as metas estabelecidas, gerando uma maior competitividade à empresa no mercado. Obteve-se com este projeto uma forte redução do Lead Time e da quantidade dos ensaios laboratoriais dentro de um prazo estabelecido, permitindo uma liberação para faturamento no mesmo dia de produção em 80% da produção deste produto.

Aug 7, 2018

By John P. Walsted

Because of the absence of an iron-producing industry, the Pacific Northwest is working under an economic handicap. This is particularly apparent in the gray-iron-foundry industry because of the high price of pig iron imported from foreign sources or shipped in from producing ?areas within the United States. The high prices and sometimes short supply of ferrous metal products has put a brake on industrialization, which has been only partly compensated by the availability of cheap electric power. The economic condition of the gray-iron-foundry industry could be improved by establishing a small iron-producing industry based on the locally available ores. Moreover, establishing a local iron smelter would create a market for resources now dormant. Low-grade ores of manganese, chromium, and nickel would become usable in industry when combined with the iron ore from Scappoose. Pig iron produced in even limited quantities would level out the fluctuation in supply. The ore deposits, being small, would not supply enough pig iron to satisfy the entire demand. This condition necessitates designing special pig irons that will carry abnormally high proportions of scrap in the cupola charge.

Jan 1, 1955

By J. H. Adkins

The purpose of this research is to identify hazards associated with roof bolting and to make recommendations for procedural and equipment design changes to reduce those hazards. To that end, the project reviewed Literature on related research, collected and analyzed roof bolting injury data, normalized the injury data be exposure time to each activity and identified problem areas within the root bolting tasks. In addition, field data collection forms were prepared and mines selected for field work. In the field, observations were made of eighty (80) different roof bolting crews bolting one hundred fifty-five (155) place;, on forty (40) sections spread among nine (9) mines. Task analysis forms were used to record unsafe behavior or conditions for each crew and each place. Informal discussions were held with the mine's safety and training officer, the maintenance officer, one section foremen and, when possible, the observed crew, concerning the training and experience of the miners. Unsafe acts were categorized and related to the "Activity While Injured" categories developed during the accident analysis. For each of these categories one or more recommendations for corrective measure, machine modification, procedural change or job training were developed. The study produced over fifty (50) specific recommendations involving machine design, procedural, safety training and supervisional issues that would lead to reduced roof bolter injuries in the near term. The authors concluded, however, that only the development of truly hands off/remote bolting can eliminate or reduce to an absolute minimum the hazards to which the roof bolter is subjected.

Jan 1, 1977

By Alfred L. Ransome

The plan to develop a standard system of names and definitions of regions and districts in Alaska was borne of the need for a tool to use in statistical and economic studies of the mineral industry of the Territory. The purpose of this report is to present to the mineral industry, and to those individuals interested in the mineral or allied industries in Alaska, the system used by the Bureau of Mines in connection with its legal function of collecting and disseminating mineral statistics. It is hoped that the specific descriptions given will result in a more complete understanding of what is meant by the regional and district names that appear in publications of the Bureau of Mines relative to the mineral industry of the Territory. Problem of Standardization of Names and Definitions The question might be asked, does the naming and defining of regions and districts in Alaska present a problem relative to the establishment of a standard? Is it necessary to establish a standard?

Jan 1, 1954

By W. K. Overbey

Surface fracture trace density, changes in roof rock type, and topographic unloading due to drainage were mapped for the mining areas located in the Blacksville-Osage, W. Va., quadrangles to investigate their influence on mine roof falls. Using these factors, a technique was developed to predict probable roof fall areas ahead of projected mining operations. As a feasibility test of this proposed technique, areas were delineated where one, two, and all three of these factors were operating to formulate a "potential hazard map" for comparison with roof fall observations that were made. The limited evidence suggests that in combination these factors are reliable predictors of where roof falls are likely to occur. This technique promises to be a useful tool in planning mining operations.

Jan 1, 1973

By Jack Eloranta

This paper documents the relationship between material handling and processing coete compared to blasting cost. The old adage, "The cheapest crushing is done in the pit", appears accurate in this c!ase study. Comparison of the accumulated cost of: powder, selected wear materials and electricity; indicate a strong. inverse correlation with powder factor (lbe powder/long ton of rock). In this case, the increased powder cost is more than offset by electrical savings alone.

Jan 1, 1995

By Samuel Canchanya M.

El presente trabajo describe la mineralogía y génesis de los depósitos de cobre, plomo, plata y zinc de la mina Bella Unión ubicada en Hualcayoc, Cajamarca. En este sentido, la geología de dicho yacimiento presenta vetas como mantos. Así también se plantea la existencia de cuerpos estratoligados sin genéticos que se desarrollan en horizontes calcáreos albianos y coetáneos con los yacimientos en rocas volcánicas y dentro del lado oeste de los lados peruanos.

Nov 8, 1982

By Charles B. Carpenter

When a drilling well strikes a horizon in which there is a large volume of petroleum or natural gas under high pressure, danger of a blowout with disastrous results is imminent unless proper precautionary measures are taken. The history of oil-swell drilling has been marked by many blow-outs and wild wells, some of which-have caught fire and burned for long periods. Such incidents nearly always make headline news, but ordinarily few persons realize that what to them is an interesting newspaper item may entail great financial loss to the operator and frequently loss of life or personal injury to members of the drilling crew and others in the vicinity of the well. The blow-out, wild well, and crater are dreaded specters to every thoughtful person in the oil industry because of danger to life and property, underground damage to surrounding wells, dissipation of reservoir energy, and waste of irreplaceable natural resources that blow to the air or migrate to barren formations. Every operator drilling in high-pressure fields must be on the alert always to forestall any conditions that may lead to a blow-out, and his vigilance must not cease until a well is completed and oil, gas, or both are flowing to storage or market.

Jan 1, 1937

By Noriyuki Fujii

It is no need to say that exploitation of industrial minerals has a close relation to development of the industries related. In the first stage, a small scale manufactures were initiated in areas producing some main raw material minerals. China and cement manufactures, for example, were established depending on the local occurrence of raw materials such as kaolin and limestone without exception. That is, the industrial development is greatly influenced by the local production of the raw materials in the stage. With the development of industrial technology, various kinds of raw material minerals are explored to meet the demands of industries in the second stage. New materials become indispensable, and low-grade raw material minerals, which were left as useless, are developed as useful materials. In the stage, the development of raw material minerals is accelerated by that of industrial technology related. However, industries mainly rely on domestic production of the min raw material minerals.

Jan 1, 1981

By Robert S. Sanford

Intensive investigations of domestic manganese deposits were conducted by the Bureau of Mines and the Geological Survey during the earlier part of the war minerals investigations when there was doubt that the quantity of manganese needed to produce the greatly increased tonnage of steel demanded for war supplies could' to obtained from its customary sources. Domestic deposits of ores that contain sufficient manganese for direct production of ferromanganese essential in steel Manufacture are generally small, and the bulk of the supply is imported. One of the few large deposits of low-grade manganese ore known in the United States is in the Artillery Peale district in southern Mohave County, Ariz. Manganiforous sediments underlie a very large area. Several large groups of claims, covering the most of the manganese-bearing ground, wore assembled in 1929 and 1930. The greater part of this area was leased by the M. A. Hanna Co. in 1937. Investigations by engineers and geologists for this company revealed that the average content of manganese is very low; but that the Maggio Canyon area, about 180 acres, contains higher-grade material. The company put down 28 vertical diamond-drill holds to explore this ground, under the direction of B. N. Wobbor, geologist.

Jan 1, 1948

By Arnold M. Lansche

[Selenium and tellurium are rare elements in the earth's crust. Their scarcity and primary dependence of supply on copper and lead output are in consonance with the relatively small quantities consumed at 1964 level. Production depending on output of copper and lead creates a supply situation- which would appear to militate against development of large-scale usage of these elements. However, supplies have adequately met. demand in the past decade and can be increased substantially if warranted by new uses for either selenium or tellurium Ores of copper and lead re the principal sources of selenium and tellurium. Byproducts from the smelting and refining of copper and lead concentrates are incorporated in refinery anode slimes from which selenium and tellurium metal are recovered.]

Jan 1, 1967

By The Staff

"THE property of Red Mountain Mines Limited is located 11/2 miles north and west of the town of Rossland, in southern British Columbia. The mine is situated on the flank of Red mountain, famous in pioneer days as the site of a number of profitable gold-copper producers. Mining and milling commenced in May, 1966, and by the first of July the concentrator was treating close to its average design capacity of 400 tons per day. The following description of the property and its operations is divided into three parts, dealing respectively with geology, mining and milling.GeologyAll the known ore reserves of Red Mountain Mines occur on the Coxey claim, on the west slope of Red mountain. Although there are indications of molybdenite mineralization elsewhere on the Company's property, these have not been developed.The Coxey and adjoining areas are underlain by the Mount Roberts formation of the Rossland volca-nics. This formation consists of an interbedded series of volcanic and sedimentary rocks, mostly brecciated and silicified near the ore zone, and all intruded by igneous rocks which occur in various forms, and vary in composition from basic to acid. The country rock in the vicinity of the mineralization seems to be mostly a volcanic, approximately andesitic in composition, and possibly a surface flow. There is much banding, some of which is undoubtedly due to tuff and agglomerate layers, and some to narrow, siliceous, sedimentary horizons such as the surface exposure of the main ""A"" orebody, much of which was a thin capping of greyish banded rock that looked like quartzite. The drill holes also intersected occasional layers of black, argillaceous quartzite, sometimes altered to a greenish colour. The whole assemblage has been silicified with varied intensity, sometimes to such an extent as to have obscured or obliterated the original characteristics. The mineralized zone has also been strongly brecciated, the fragments varying in size from less than an inch up to large masses, best described as a mega-breccia. Anomalous results obtained in drilling, such as sedimentary sections that do not appear in adjoining holes, may sometimes be due to the presence of these large blocks, no longer in their original position. The whole volcanic unit is thus very complex and confusing. For practical purposes, the ore may be said to occur in a greenstone formation with minor sedimentary interbeds and considerable later igneous material."

Jan 1, 1967

By A Giblett, M Daniel

"The Global Mining Standards and Guidelines Group (GMSG) currently supports nine individual industry working groups focused on developing standards and guidelines for the mining industry. In 2013 the GMSG established the Industrial Comminution Efficiency (ICE) working group to develop freely available guidelines for plant operators to quantify the operating efficiency of industrial comminution circuits. This initiative has engaged a diverse group of representatives from mining companies, equipment vendors, consultants and metallurgical laboratories with vast experience and capabilities in the field of comminution. The GMSG has issued the first two guidelines from the ICE working group in 2015–2016, with the third guideline having completed the approvals process and being in the final stages of editing ahead of release later in 2016.Two of the ICE guidelines present methods to quantify comminution circuit efficiency, and a complementary guideline describes best practice methods to collect the necessary samples and data to furnish these assessments. Collectively the guidelines cover sampling, survey data collection, laboratory testing procedures and calculation processes to allow the user to generate a relative circuit efficiency factor for the comminution circuit at the time of survey. The reference energy consumption is calculated considering the measured F80, P80 and ore strength at the time of survey, using either or both of the Bond or Morrell methods presented in GMSG guidelines dedicated to each method. The guidelines consequently provide the end user with practical tools to perform circuit efficiency analysis and to readily quantify the impact of optimisation efforts.This paper presents the content of the three ICE guidelines and describes their intended application.Citation:Giblett, A and Daniel, M, 2016. Global Mining Standards and Guidelines for Determining Comminution Circuit Efficiency, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 3–8 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By J Harris, P Kirsch, D Cliff, M Spinks, S Goater, D Sprott

Fires are a common and recurrent unwanted event in the operation of open pit mines. In most cases, the causes of events such as fires are already æknownÆ but are either overlooked or not fully addressed in planning. Ongoing rapid growth of the global mining industry is creating a scarcity of skilled personnel, and high turnover within operations. This contributes to loss of corporate memory in risk management activities. RISKGATE« is an online risk management system designed to support and assist in the analysis of priority unwanted events in Australian coal mining operations. Funded by the Australian Coal Association Research Program (ACARP), RISKGATE« is a knowledge management program that delivers best-practice controls for unwanted events and assists operations in staying abreast of emergent risks and threats. RISKGATE« content has been primarily developed from an association of industry experts, and enriched with input from additional academic and technological resources. In mining operations, RISKGATE« provides a continuum of knowledge and best practice for risk identification, assessment and management. RISKGATE« will assist companies in improving safety performance, operational efficiency, operating practice and training. Here we present the RISKGATE« prototype as developed in 2011 for Fires, with a case study presented for the initiating event Fires on Mobile Plant.CITATION:Harris, J, Sprott, D, Spinks, M, Cliff, D, Goater, S and Kirsch, P, 2012. RISKGATE« - A case study in application to fires on mobile plant, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 49-54 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

By Moe Momayez

Shotcrete is a practical and economical support system in many Canadian underground mines. Although shotcrete technology has gained acceptance in the mining industry, there are some problems that have emerged with respect to quality assessment and thickness measurement of the liner. This paper presents recent tests performed with a miniature seismic reflection device developed primarily for thickness measurement of this heterogeneous liner. Work was performed on site in an underground mine in Ontario, Canada. This paper also presents the results from laboratory tests performed on fibre reinforced and non-reinforced shotcrete panels that were used to assess the P-wave velocity in both materials. The results of these tests were used in a second on site investigation. The NDT thickness measurements showed good agreement with direct thickness measurement such as coring.

May 1, 2001

By Brad H. A Brown, J Paul Tidman

To design a blast, one must give consideration to safety, economics, geometry, geology, production needs, and a variety of other requirements. To compare designs requires the time to develop alternatives, analyze, and then improve on them. A number of tools are available to assist with the first set of requirements, however they are poorly integrated. SHOTPlus is a program to improve the efficiency of blasting operations, by combining measurement and blast design tools, and offers the user the time and means to modify designs and explore alternatives.

Jan 1, 1997

By Floyd Varley

In deep and highly-stressed coal mining, advanced design practices are used to minimize the potential for damaging events to occur. Despite these design efforts, the hazard of coal mine bumps can not be completely eliminated. This paper will review current and historic work practices used internationally to minimize the hazard to miners from mining in conditions which could produce a bump. These site specific work practices have a common base in monitoring for conditions which could result in a bump and application of controls to prevent the occurrence or minimize the severity of an event where miners are working. Monitoring practices range from purely observational to semi quantitative. Control methods attempt to initiate events in a controlled manner, absorb the energy of a potential event or reduce the potential for or magnitude of an event by altering the stress conditions of the mine workings. Building from the experiences of other coal fields, an empirical framework to manage the potential hazard of coal mine bumps can be developed to enhance the level of safety provided by prudent mine design.

Jan 1, 2008

By L. D. Schmidt, W. C. Schroeder, A. C. Fieldner

"INTRODUCTION The highly mechanized character of modern warfare makes steel the most vital raw material. The shortage of steel scrap in the United States is forcing the use of increased quantities of pig iron in steel manufacture, so that the rate of pig-iron output will continue to be the controlling factor in steel production. 5/ At the same time, the construction of new blast furnaces is limited both by time and the amount of strategic material available. Under such circumstances, every effort must be made to attain and then maintain maximum pig-iron output from the equipment now in use.When forcing a blast furnace to the ultimate in production the highest standards for quality and uniformity of the coke must be maintained. In view of these facts, the Bureau of Mines, in cooperation with the Office of the Solid Fuels Coordinator for War, is surveying the coke industry to study the various steps in producing coke of higher quality and greater uniformity. 6/ The engineers conducting the survey are visiting key men in coke-oven and blast-furnace organizations to determine, first, the major and most common problems in coke production and use; and, second, the best and quickest method for solving them. Various operators have made good progress in solving individual problems, and a Nation-wide exchange of information among them will make possible widespread adoption of the best practices. It is the purpose, of the survey and reports such as this preliminary one to facilitate such exchange of information. As an outgrowth of the survey, it was soon revealed that many operators could be helped by cooperation with various Government agencies, particularly to procure suitable coals, minor additions to equipment facilities, and tests on certain properties of coal or coke, or specific advice concerning the operation of various types of equipment. The machinery and organization necessary for securing this cooperation have been set up as a part of this work."

May 1, 1943

By J. A. Fellows, Earnshaw Cook, Howard S. Avery

HEAT-RESISTANT alloys of the higher nickel and chromium ranges have been empirically developed through the practical experience of the past two decades to a position of significant industrial importance. Few quantitative metallurgical data have been published, however, that could be related directly to engineering specifications and design. Inadequate information led to the inauguration, in 1934, of a research directed toward a better understanding of the properties and performance of these steels at temperatures between 1400° and 2000°F. Investigation was concentrated upon the 26 per cent Cr:12 per cent Ni type, which owes its extensive application to an excellent combination of economy, strength and surface stability at elevated temperatures. The requirements of the oil-refining industry have been prominent in influencing the scope and evolution of the program. Creep strength at the maximum allowable deformation ranges has been employed to evaluate the merits of these alloys. Permissible elongation rates vary from 1.0 per cent in one million hours for turbine blades to 1.o per cent in ten thousand hours for tube supports and heating-furnace equipment. Throughout this paper, the limiting creep stress (L.C.S.) for a given temperature has been defined as the stress that will produce a uniform elongation rate (stage II) of one per cent in ten thousand hours as extrapolated from rates per hour or tests of less than two thousand hours duration. Certain current specifications require a minimum L.C.S. of 1600 lb. per sq. in. at 1800°F., of 3600 lb. per sq. in. at 1400°F., and include a tensile acceptance test at room temperature, after aging for 24 hr. at 1400°F., as a measure of embrittlement in service. An elongation of 4 per cent is considered satisfactory for general use, while a minimum of 9 per cent is prescribed on occasion. Many differences of opinion concerning the properties and performance of these alloys appear to result from their sensitivity to unappreciated variations of chemical analyses which, for example, may change their L.C.S. from 3500 to 350 lb. per sq. in. at 1800°F. Within broad chemical limits, it is possible to balance the six or more important elements present to attain desirable properties with a number of different combinations. One method for adjusting the composition has been described under the sponsorship of the Alloy Casting Institute,1 in which, by maintaining a substantially austenitic* alloy, optimum creep strength and minimum tendency to embrittle after aging are expected. Unless, however, the limits are undesirably dose, it has not been possible to ensure a moderate range of strength and of ductility by any chemical specification alone. There is a definite need

Jan 1, 1942