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"The profile of the respondents was that of a professional responsible for communications, community relations or corporate social responsibility programs. By targeting a consistent professional profile it was possible to ensure that most respondents had a similar degree of responsibility and/or decision-making ability related to the application of communication technologies. The research attempted to be inclusive and attention was paid to interview respondents from both genders and from indigenous groups.4, 5 A codebook of 80 themes was developed that highlighted recurring topics; for example, codes were created to identify risks, benefits, policies and learning process of using social media and included topics that were repeatedly emphasized by respondents (i.e. age, efficiency and language). Both manifest coding (i.e. coding of the visible content, such as specific words) and latent coding (i.e. coding of underlying meanings) was undertaken (Creswell [13]). The codes were used in the qualitative analysis using ATLAS.ti software and network views were created to illustrate the relationship between major themes of this research. There are limitations to this research, largely related to the changing nature of the Internet and communication technologies. There is also a geographic limitation to the application of this research because most of the data was gathered primarily from Canadian sources.6 Different levels of Internet penetration, or limited access to computers or mobile devices, and low literacy rates may reduce the applicability of the research in countries with low Internet penetration. A more systematic process to selecting candidates may have helped bring balance to the final list of interview respondents. For example, most of the corporate respondents were from medium and large companies and there was not adequate representation of small mineral exploration companies. The research did not probe into social media applications by different business groups within the mining sector, such as smelting and processing."

Jan 1, 2011

By J. D. de V. Louw

Introduction Zircon is a natural occurring mineral and may exhibit natural low level radioactivity. It contains trace levels (90 to120 pCi/g and 110 to 115 pCi/g respectively or 3.3 to 4.4Bq/g and 4.1 to 4.3 Bq/g) of naturally occurring radioactive uranium and thorium. This mineral is often found in a suiteof minerals (rutile, ilmenite and monazite) Due to the overlap in physical properties of monazite (containing 4–7% thorium) with some of the zircon (slight magnetic susceptibility) it often contaminates the zircon, adding to the levels of thorium in the product. Hazards associated with the products from zircon and its processing is inhalation of respirable dust (generated by milling) containing radioactive uranium and thorium which may cause cancer of the lungs. Legislature regulates the transport, use, workplace environment exposure and storage of radioactive material. In America the general regulation for the unlicensed use of low levels of radioactive materials limits the concentration to 500 ppm (U plus Th). Europe (IAEA) specifies a limit of10 Bg/g (Bequerels per gram) on the parents for transport only which is a higher level of U+Th. Companies selling into these markets need to comply with these regulations and certification is therefore required, not only of the major constituents determining the price, but of the U and Th levels as well. Exceeding the limits for U and Th may result in material being returned to the country of origin. However, for the analyst the requirement is to analyse for these elements throughout the production process as well as the analysis of the ‘tails’ that is returned to the mine area. This requires a wide range of concentration to be analysed. Methods of analysis A wide variety of methods exist for the analysis of U and Th in a range of matrices. (Table I) All these methods have been used with varying degrees of success in terms of accuracy. Overall precision for the different techniques varies from 5 to 25% relative. Time to produce results from these methods vary from a few minutes to several days. The Production Chemist is expected to produce between5 and 10 analyses per hour for process control purposes. A suitable technique that fits this requirement is X-Ray Fluorescence. Both Wavelength Dispersive (WDXRF) and Energy Dispersive X-Ray (EDX) instruments are suitable. X-Ray analysis in general has a few major advantages over competitive techniques. •It is fairly simple to set up and interferences are known and easy to correct •It has multi-element analysis capabilities •Clean spectral lines for U and Th (in zircon specifically) •Uncomplicated and easy to measure background •Low detection limits (3 to 5 ppm) •A very high degree of precision •Sample preparation is uncomplicated and fast (pressed powders and fused beads). In Zircon (ZrSiO4) processed sands the matrix is constant(>99% ZrSiO4) and the background is thus essentially constant. A typical set up for the analysis of U and Th by WDXRFis given below: X-Ray Tube Tungsten (W) Target, 2.5 to 3kW operated at 50mA/50kV Crystal LiF200 (or LIF220 for higher resolution) Analytical Lines (2?)U La1,226.14Th La1,227.47 Detector Scintillation Counter Analysis time, depending on the concentration can vary from as little as 20 seconds up to 5 minutes. Standards As with any other comparative technique XRF analysis relies heavily on the quality of the standards used. Assuming proper set-up and operation of the instrumentation as well as consistent sample preparation, accuracy is determined by the quality of the initial calibration standards. A search for the available zircon certified reference materials (CRMs) shows that there are only a few CRMs

Jan 1, 2003

By G. J. Olson

This paper describes the microbiology basics underlying heap and tank biooxidation of metal sulfide ores and concentrates. The primary organisms are identified and described along with the reactions they catalyze and their growth requirements. Also described is the interaction between ore leaching bacteria and the leaching environment in terms of solution chemistry, temperature, and mineral precipitation. Specific factors and agents that stimulate or inhibit growth and activity of ore bioleaching will be identified. Some of these factors are organism-specific and others are generic for microorganisms that grow under acidic conditions. Current knowledge of the limits of bioleaching in terms of dissolved ions in leach solutions, pH, and temperature will be summarized.

Jan 1, 2003

By L. Juteau

"""The north coast of the St. Lawrence River will be the scene of an industrial development during the coming decades"". The facts which underlie this statement are the occurrences of iron and titanium ore, the abundance of hydro-power and the availability of deep-water ports in this region. Havre St-Pierre, Sept-Iles, Port Cartier and Baie Corneau already exist as major ports and urban centers. The huge quartz deposit at Baie Comeau will be a decisive contributing factor in the development of a metallurgical plant in this area. Due to its purity, it lends itself, first of all, to the manufacture of glass of different kinds, being comparable to the quartz sands now used by the plate glass and glass container industries in the Montreal area, Moncton, N.B., Trois-Rivieres and - in the future - at Bécancour, Quebec. However, its high quality will also make it possible to use it as one of the main basic materials for the production of silicon carbide and ferrosilicon, and as a flux in metallurgical processes. It is intended, in this report, to offer conclusive proof of the economical importance of this large quartz deposit by presenting the results of the studies made to date."

Jan 1, 1971

By Harry W. Campbell

In 1984 and 1985, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied part of the Meadow Valley Range Wilderness Study Area (NV-050-156) in order to evaluate its identified mineral resources. The study area is located in Clark and Lincoln Counties, NV, about 50 miles northeast of Las Vegas, NV. The Johnston and Fitchett prospect, in the northern part of the study area, has more than 3 million tons of marginal perlite reserves suitable for many commercial uses. A preliminary mining feasibility estimate suggests perlite could be profitably mined from the study area; however, it is unlikely these perlite deposits will be developed in the foreseeable future because of unfavorable market conditions. Zeolite minerals occur in alteration zones adjacent to perlite deposits at the Johnston and Fitchett prospect, but high quality material is closer to potential markets. A metalliferous black shale unit containing 800,000 tons of subeconomic resources may extend into the study area at the Bradshaw vanadium prospect on the northwest boundary. Limestone, stone, sand, and gravel occurrences are wide-spread, but other suitable deposits in the region are more accessible to potential markets. Seven prospects in and near the study area were examined. The entire study area is leased for oil and gas exploration. A group of perlite placer claims covering more than 480 acres was located in the 1940's in the northern part of the study area. A small group of lode claims was located in the mid 1950's in the southwest part of the study area. No mining claims are currently (1985) held inside the study area. No mineral production is known from within the study area.

Jan 1, 1987

In the last 40 years, New Zealand has developed a number of liquid- dominated geothermal steam fields, for electricity generation and indus- trial process steam. New technologies were developed, and in this work, New Zealand led the world. The policy of full publication of the results, in a wide range of sciences, provided a reservoir of detailed data defin- ing the geology, size and shape, and the chemical and physical regime, of many geothermal fields and their constituent parts. The discovery of precious and base metal deposits /precipitates in geothermal drill cores and steamfield equipment, suggested a clear link- age with epithermal mineral fields in general, and with that of the Coromandel (Hauraki) Region in particular. Further work on geothermal/ epithermal relationships have implied that the techniques, developed to obtain an understanding of geothermal fields, could be applied also to epithermal mineral exploration. This work is developing fast, and is now proceeding in many coun- tries. Future work may show that the presumed relationship between geothermal and epithermal deposits may be applicable in the wider con- texts of all hydrothermal deposits, and possibly in many other minera- lised areas with volcanic "country rocks".

Jan 1, 1988

By M. Hamarat

Freeport-McMoRan Copper & Gold (FCX) is committed to preserving and enhancing biodiversity in the areas in which we operate. As a member of the ICMM, FCX is committed to implement the 10 Sustainable Development (SD) Principles throughout our business. FCX is also a member of the Wildlife Habitat Council (WHC), a nonprofit coalition dedicated to protecting and enhancing wildl ife habitat. In alignment with ICMM SD Principle 7 and our Environmental Policy, FCX has set a performance goal to prepare a biodiversity inventory in 2010 and land management plan by end of 2011 for all active mining sites. In 2010 FCX established a Biodiversity Task Force to assist sites in biodiversity management; optimize use of resources around the globe; implement FCX goals and targets; and align biodiversity programs with ICMM principles and guidance. The task force consists of Environment and SD Department management, scientists and engineers from FCX sites, and WHC staff. The Task Force recently issued a biodiversity inventory guidance document to set expectations and provide consistency across the sites when developing a biodiversity inventory and land management plan.

Jan 1, 2011

By F. F. Roberto, E. Kirby, A. R. Marchbank

The application of biologically assisted methods for metal extraction in the mining industry has a long history, but development of modern techniques has been relatively slow. There is, however, a resurgence of interest in the industry with the recent development of methods to successfully treat base metals concentrates. Two major pilot plant programs for treatment of chalcopyrite concentrates have been initiated in the past year and results from one are beginning to be released. This paper provides an overview of methods that have been applied in the past, from the earliest deliberate applications of the technology, through the copper and uranium heap and dump leach applications, the more highly engineered agitated tank leach gold applications and the developments currently taking place in the industry.

Jan 1, 2003

By C. G. Buttleman, W. C. Brice

In Minnesota, reclamation of active aggregate mining sites is primarily regulated through local permits issued at the county, township, or municipality. However, for abandoned or depleted aggregate mining sites, a responsible party for reclamation is often no longer available. Since 1995, the Minnesota Department of Natural Resources has reclaimed several abandoned aggregate sites using innovative public/private partnerships and emphasizing native plant materials. The purpose of these projects is to demonstrate cost effective reclamation methods that can be utilized by both aggregate operators and local government and to promote mine planning and resource identification as it relates to reclamation.

Jan 1, 2000

Jan 1, 1967

Termination of membership In accordance with By-Law 7.6.1. of the Constitution of the Institute, the names of the undermentioned members have been removed from the membership register. Colloquium and General Meeting A General Meeting and Colloquium on 'Heavy-medium separation and ore sorting' was held on 18th September, 1974, at 09h15, in Kelvin House, Johannesburg.

Jan 12, 1975

By J. J. Forbes

Probably the newest thing in mining safety, or safety for mines, is the apparent dissatisfaction on the part of the mineral industries, as represented by both management and labor, and the general public of the Nation, with the safety record of the mining industry. This is reflected by published comments and papers in the technical press;1-8 in labor periodicals, 10 11 in popular journals and periodicals,12 13 and in the daily press; also by discussions of the Safety Committees sponsored by the National Safety Council, 9, 14-15 the American Mining Congress, 1, 16 the American Institute of Mining and Metallurgical Engineers, 2, 4 the Mine Inspectors' Institute of America,6,8,17,18 the Coal Mining Institute of America, 5, 19, the American Standards Association, and others.20,21

Jan 1, 1949

By Lon A. Williams

This report, authorized under Contract Number H0220065, Amendment Number Six, documents the results of an investigation of lighting system modifications and designs for working place illumination in high and low coal entries of underground coal mines. The portable and machine mounted system designs, both modified and prototype, represent a continuation of work performed under Contract Number H0111403, Amendment Number One. See the Final Technical Report dated May 26, 1972 for detailed information concerning this prior Contract. All modified and prototype systems met the performance requirements of Bureau of Mines Specification 2G, as proved by test. In addition, the systems met the requirement for illumination, as specified in the Contract and in the proposed standards which were generated in response to Public Law 91-173.

Jan 1, 1976

By R. C. Ford, W. L. Niccoli, J. B. Finley

All mining operations are superimposed on natural hydrologic systems. As a result, mining operations are influenced by natural hydrologic processes and require water management systems to successfully conduct mining activities. Managing water and mining-related solutions is a critical task at all stages of the mine life because of the time-dependent nature of natural and mining-related flows. Effective operation of the mining water management system requires a “systems” approach that integrates the time-dependent effects of all water and mine solution handling components. This paper discusses the concept and application of dynamic systems modeling to address the time dependent nature of mining water management systems.

Jan 1, 2002

By Harvey Parker

The International Tunnelling and Under-ground Space Association (ITA) is a nonprofit organization that represents all aspects of the tunneling and underground space industry worldwide. The United States has had a prominent role in ITA since its 1974 inception. ITA was formed as a result of a worldwide survey conducted in the early 1970s by the Organization for Economic Cooperation and Development (OECD). Bill Lucke was in charge of tunnels for the U.S. Federal Railroad Administration and was a member of the organizing committee that created ITA. He became a vice president of ITA. Jack Lemley served as President of ITA from 1983 to 1986. Dick Robbins was very active in ITA and served for many years both as a member of the Executive Council and as First Vice President. Harvey Parker has served as President of ITA for the last three years and will serve as Past President for the next three years. Moreover, there are many individuals and companies from the United States that have contributed significantly to the activities and the success of ITA. There have been several active Working Group Animateurs from the U.S. and there have been significant contributions from many individuals as well as companies from the U.S. Several engineers from the U.S. are currently serving ITA in a leadership role. The Underground Construction Association of SME (UCA of SME) is the official organization representing the U.S.. SME Executive. [ ] Director Dave Kanagy and UCA President Tom Peyton were instrumental in the U.S.?s role at ITA during the last few years. Peyton has been the official delegate to ITA. Henry Russell and Christian Ingerslev are both Animateurs of ITA working groups. This article will introduce ITA and its activities. A subsequent article will describe the ITA in more detail and will discuss the significant role the U.S. has played in the development and success of ITA.

Jan 1, 2007

The Institute has set important objectives for 1988 to make the Institute still more purposeful. Precious metals The Second International Symposium on Mining, Extraction, and Processing of Precious Metals will be held in Las Vegas, Nevada, USA, during the 118th TMSAIME Annual Meeting in March 1989. The First International Symposium on Precious Metals.

Jan 1, 1987

By Michael W. Russnak

Productivity and operating expenses are everything when it comes to judging how well your mine and company are doing. Stakeholders are always looking at these numbers and trying to understand if productivity is improving, if operating costs are trending downward and what you are basing your decisions on. o make improvements you first need to understand how you are performing. If you can?t get this basic information, you will never improve. You will not be able to make simple decisions related to maintenance, operations or production. Forget about planning, as you will only be guessing based on the numbers some stakeholder or your executive wants to see. The problem miners run into is not that the data doesn?t exist; it does, but typically it?s raw, it?s everywhere and its volume is huge. Today there is more on-board computing capability in shovels than we had on our desktops three years ago. Add other mobile equipment, plant systems and multiple OEM vendors to the equation and the challenge is daunting.

May 1, 2007

In November 1986 the Australian Minerals and Energy Council (AMEC) endorsed an "Australian Code for Reporting Identified Coal Resources and Reserves" for use by the Federal and all State Governments. Before this endorsement there were six different coal codes in use in Australia. The code is broad in nature to accommodate the wide range of coal deposits in terms of rank, quality and geological environment, that are present in Australia. In the code, Resources refer to all of the coal in situ which may have potential for use and the various categories indicate the level of confidence of the assessment. Reserves are those Resources which are planned to be mined and for which such planning has been undertaken. Only minimum guidelines are set by the code and the onus is on the estimator to state clearly the criteria used in any Assessment.

Jan 1, 1987

By Reginald Dias

Mining operations take a tremendous toll on equipment, operating in difficult conditions day after day. Owners and operators cannot make the job any easier, but they can give their equipment an advantage. Equipment life may be extended through preventive maintenance and the proper application of quality lubricants. This means lubricants that are made to last longer and stand up better to the punishment mining equipment must endure. There are several practices to consider as part of a successful preventive maintenance program. A good place to start is to review original equipment manufacturer recommendations about servicing and maintenance intervals for each part of the equipment, especially the engine. If these recommendations have not been followed, owners and operators must begin periodic service work on equipment to help minimize equipment down-time and extend engine life.

Jan 1, 2003

By L. K. Smith

The position of Australia as a continuing long-term supplier of mineral sands, and their upgraded products, has been reinforced with the discovery of the extensive mineral reserves in the Murray Basin, an area covering parts of South Australia, New South Wales and Victoria. A major impurity in the Murray Basin is chromium, mainly present in ilmenite concentrates as individual chrome spinel grains. Magnetizing roast treatments are being evaluated as a means of removing the chrome spinel impurity from the ilmenite and as a result of the roast and magnetic separation treatments, the chrome spinels can be expected to be concentrated in the non-magnetic reject fractions. It is from these fractions that attempts were made in this study to recover a chromium-rich product by magnetic fractionation and by application of flotation. The high gauss non-magnetic rejects from the roasting of a primary and a secondary ilmenite fraction were magnetically fractionated to obtain a product with 40.5 and 28.7 per cent Cr2O3,respectively. From the high gauss non-magnetic reject from the roasting of a primary ilmenite, flotation produced a chromium-rich product assaying 29.5 wt per cent Cr2O3at 69.0 per cent recovery. In another test a magnetic fraction assaying 32.9 wt per cent Cr2O3was floated to yield a chromium-rich product with 39.7 wt per cent Cr2O3at 96.4 per cent recovery. X-ray diffraction patterns of all the products indicated that the spinel concentrated was a ferroan magnesiochromite with rutile, ilmenite and hematite as impurities. Since all products were from a single pass, further processing can be expected to remove the impurity minerals and yield higher grade products. The material produced from the Murray Basin ilmenites in this study had similar compositions to commercial chromite ores, except for titania levels that were much higher. The high titania levels were due to residual rutile in the products, but it is expected that this can be removed with further processing. The mineral sand deposits in the Murray Basin are scattered over a wide area and the amount of chromite that may be produced from each of these deposits is unlikely to be sufficient to support an export market. Consequently, any chromite produced in the Murray Basin will most likely need to be processed locally to value added products for a niche market such as chemicals production. Keywords: Murray Basin, ilmenite, chrome spinel, roasting, magnetic separation, chromite ore

Jan 1, 2003