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By André. C. Louw

Diamond production from the reworked beach and river channel gravels along the west coasts of South Africa and Namibia is well known throughout the world, not only for the exceptional quality of the diamonds, but also for the sheer scope of the operations. To date an estimated 140 million carats have been produced from the resource worth some US$40 billion in today's money terms. It is therefore not surprising that it didn't take long before the attention turned towards the possible extension of this valuable diamond resource on similar submerged beaches in the adjacent territorial waters of South Africa and Namibia. This has proved to be a very successful move as the marine production in Namibia today constitutes 48% of that country's total diamond production. Although small scale recovery of diamonds from the sea commenced in the 1950's, the first large scale production came from the operations of the Texan entrepreneur, Sam Collins, in the 1960's. The De Beers Group, which took over Sam Collin's operations in 1969 had all the concession areas, as well as the financial and human resources to tackle the new mining frontier in the correct way by years of data gathering (ie diamond reserves and seafloor terrain studies) before commencing with large scale mining operations in the 1980's. Those who are familiar with the beach mining operations along the South African and Namibian west coasts will have appreciation for the daunting task of surgically removing the payable portion of diamond deposits from the non-payable material on the one hand, and the complex uneven fractured and gullied bed-rock floor of the deposits on the other hand. Not to mention the additional complexities of large boulders and hard calcretised diamond gravel layers (conglomerate) which are sometimes associated with the deposits. It was a natural development that the sea diamond mining operations were approached with the known information of the land operations, attempting to duplicate land mining operations in the sea, but taking cognisance of the variations of the terrain in the different areas. For instance, we encounter the following variations, and combinations, off the Namibian Coast. ? Close inshore - holocene sand cover often masks large areas of potentially diamondiferous gravels. ? In midwater areas (40m - 100m)

Jan 1, 1998

By Manfred Krutein

Ocean mining has a number of problems which are critical to its development: ? Political hurdles on national and international stages ? The worldwide economic situation, with the possibliity of a recession ? Financial difficulties in funding further work ? Technical problems for the development of ocean mining and transport subsystems ? Demands for technology transfer This paper touches the last two points and provides some thoughts for discussion and creative objectification. The many technical problems of ocean mining will be identified and some proposed solutions will be investigated relative to the state-of-the-art technology of ocean mining and nodule transport. An outlook into the future attempts identification of the steps necessary to eventually develop components for workable systems that are not only technically but also economically feasible.

Jan 1, 1978

By Hewitt Wilson

A review is given of the nomenclature, sources, imports, statistics, common methods of preparation, and testing of mineral pigments. A description of the Deer Park-Spokane colored-clay district and the laboratory methods of preparation of these colored clays, others, and siennas follows. The mineral pigments were prepared by washing or grinding the original material as received and by calcination of the yellow ocher and brown sienna with and without manganese dioxide to produce red, brown, and black colors. These prepared powders were tested for fineness, oil absorption, and color as compared with well-known brands of commercial pigments. Similar tests were made with several basalt red clays occurring in the neighborhood of Salem, Oreg., and Kalama, Eatonville, and Clay City, Wash. The color particularly was studied, since this property is the most important commercial characteristic of the minerals. PURPOSE OF INVESTIGATION Since the development of the clay industry in the Pacific Northwest, some curiosity and interest have been aroused by the red and yellow clay or ocherouslike material that has often been found associated with the commercial clay deposits. These include the red and yellow "paint pots" near Deer Park and Spokane in eastern Washington, a red clay at Clay City, another close to Eatonville in western Washington, and red basalt earths near Salem, Oreg., and along the Columbia River near Kalama, Wash. Several companies have been organized to produce pigment colors from two of these deposits but have either discontinued or never started operations.

Jan 1, 1929

H. Van F. Furman, Denver, Colo. (communication to the Secretary): There are some statements in Dr. Carpenter's interesting paper which appear to require explanation, if not modification.

Jan 1, 1901

Beverley S. Randolph, Frostburg, Md. (communication to the Secretary): It has always appeared to me that each coalseam has its peculiar character or habit, due to the conditions of its formation, by virtue of which it is either persistent or variable in its section over extended areas. One seam will hold its thickness, chemical character, number and position of partings, beds of slate, etc., over a large area, while another will be found to vary in some of these characteristics every few feet. As the position of the outcrop is an accident of the topography, depending on folding and erosion which have taken place since the bed was formed, no one opening in the outcrop, or, in fact, anywhere else, can supply reliable evidence as to the general character of the seam. To determine the character of an untried seam, a number of sections are necessary from widely separated points, in order to show such variations as may exist. Should material variations be developed, more numerous sections are necessary, in

Jan 1, 1901

A. R. Ledoux,New York City: The so-called combination method " is generally used in assaying bar copper for silver. It has been modified from time to time. Briefly outlined

Jan 1, 1901

George L. Heath, South Lake Linden, Mich. (communication to the Secretary): In presenting some notes on the "Heine's Blue Test" Mr. Smith expresses a preference for fresh standards and a cheaper bottle; but this is rather a reversion to the old method, since I devised in 1897 the newer method of preparation and preservation of' permanent standards, which were not used with any success in the original method. Many busy western assayers no doubt value a method for preparing a permanent set of standards in air-tight glass-stoppered bottles, whose use brings the method as near perfection as one could desire as regards rapidity of color-reading and avoidance of unnecessary work. Mr. Smith notes that his color-readings were compared with an electrolytic assay of another ore-sample, and that my electrolytic assays were made on the " blue test" solution from colorimetric assay. He omits, however, reference to the fact, showing the advantage of my procedure, that the next column in table of

Jan 1, 1901

Jan 1, 1901

By C Chambers

"AustraliaÆs mining sector faces challenges to its competitiveness; operating costs are being adversely affected as a result of volatile commodity prices and growing international market pressures.Diesel fuel-generated power used in typical remote mining projects is generally reliable and quick-to-deploy; however it is ongoing expensive operating cost.Many mines and communities in remote locations source electricity from diesel generation, and often pay over $300/MWh in fuel and carbon only (i.e. excluding CAPEX). These costs are expected to rise over time and are vulnerable to price shock events or supply chain interruptions in international markets.Solar photovoltaic (PV) and other renewables can be integrated with existing diesel units to provide a highly reliable power supply. Such renewables now provide a cheaper source of electricity while maintaining the mining industryÆs stringent reliability requirements; some renewables are now cheaper than diesel power ù supplying electricity at approximately $226/MWh.Also, significant funding and concessional rate financing have recently become available to support the development of remote solar-diesel (or solar-wind-diesel) hybrid systems, including: up to $2.2 billion of as-yet uncommitted grants through the Australian Renewable Energy Agency (ARENA) and is now seeking mining industry partners, up to $10 billion of concessional financing for emerging renewable technologies through the Clean Energy Finance Corporation (CEFC) and this commences July 2013, ongoing revenue support through the Renewable Energy Target scheme, and other regional support programs administered by various governments.This paper explores: the business case for renewables - what applications and when to consider them, the potential operating cost savings if solar was integrated, the technical challenges and common pitfalls, and how to overcome them, and the upfront investment costs and whether the site is eligible for Government subsidy programs.CITATION:Chambers, C, 2013. Off-grid solar in the mining sector - Can renewable energy reduce your operating costs?, in Proceedings MetPlant 2013, pp 71-85 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013

By Alan K. Burton

Along with tires and transmission systems, engines have been a limiting factor in the growth of large off- highway trucks. The problem, primarily, has been the development of reliable, high-performance engines that are not prohibitively heavy or expensive. For many years, horsepower to overall truck weight ratios have been in the vicinity of 300 lb per hp for rear dump units up to 50 tons capacity. This ratio is obviously very poor when compared to the much lighter and smaller highway trucks, which frequently have a performance ratio of 100 lb per hp. Unfortunately, the larger mining trucks have not been able to match even the 50-ton trucks, and in some cases, ratios have dropped as low as 450 lb per hp. This results in a performance of only 67% of that achieved by the older smaller trucks. Thus, the message is clear: what is needed is more horsepower and less weight.

Jan 10, 1975

By J. K. Szymanski, Val Srajer

In this decade mining companies in western Canada have searched for reliable and inexpensive ways to improve mine productivity. Truck dispatching systems, equipment vital sign monitoring and sensing, vehicle guidance systems, have all been considered. In this paper the off -highway vehicle monitoring systems used or planned to be installed at surface coal mines in western Canada are described. The monitoring systems are divided according to their function and application; installation and testing procedures are described, as well as the economic benefits to the mining operation.

Jan 1, 1989

By Lon Santis, David Buckwalter, Ken Steinmetz

This paper describes a magazine security system using two readily available cellular telephone-based technologies. The system is comprised of vibration sensors and remote cameras. The system is used at a Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) licensed explosives storage location in Pennsylvania to comply with PA Department of Environmental Protection (PADEP) regulations. The system provides instant notification to the licensee via cellular modems, text messaging, phone call, and e-mail. Likewise, the licensee can control the system remotely over the internet and using text messaging commands. The vibration sensors attach to the door of the metal type I magazines magnetically and detect any movement or vibration. The cameras trigger on movement and thermal radiation changes and can also be triggered manually to check alarms received from the vibration sensors. The previous system was comprised of a base unit and magnetic strips. The magnetic strips were powered by a hard line from the control unit and mounted on the doors and top of magazine creating a bond, that when broken triggered an alarm. Our main issues with the unit were the delay in alert times and tech support. Because of these issues, we decided an upgrade was necessary. Compared to that previous system used at this site, these new systems are highly affordable, carefree and reliable.

Jan 1, 2014

By P. M. Daling

The objectives of this study were to examine a representative cross section of formal safety analysis techniques developed for the nuclear and aerospace industries, to recommend those methods that would be suitable for application to the mining industry, and to include those methods in a user's manual. Volume II of this report, the user's manual, describes several methods that were determined to be immediately transferrable to the mining industry. The handbook gives detailed instructions on appropriate application and utilization of the methods. Other techniques will require further development before they can be effectively transferred to the mining industry.

Jan 1, 2006

By P. M. Daling, C. A. Geffen

The objectives of this study were to examine a representative cross section of formal safety analysis techniques developed for the nuclear and aerospace industries, to recommend those methods that would be suitable for application to the mining industry, and to include those methods in a user's manual. Volume XI of this report, the user's manual, describes several methods that were determined to be immediately transferrable to the mining industry. The handbook gives detailed instructions on appropriate application and utilization of the methods. Other techniques will require further development before they can be effectively transferred to the mining industry.

Jan 1, 1983

By Victor V. Verbinski

This report presents the development of a raw coal concentration sensor for hydro-transport of coal and refuse (rock) from underground mines, and the results of an international test series carried out at the Colorado School of Mines Research Institute in Golden, Colorado, the U.S. Bureau of Mines, Hydraulic Transport Research Facility in Pittsburgh, Pennsylvania, Saskatchewan Research Facility in Saskatoon, Saskatchewan, Canada, and the Steinkohlenbergbauverein Test Facility in Essen, West Germany. Test results are presented for a three-component sensor and also for the more rugged two-component (all nuclear) sensor.

Jan 1, 1988

By Victor Himel

This report documents a systematic approach towards implementing an improved ensemble for the mine rescue team system that will protect against the hazards of mine rescue and recovery and will also afford improved performance through increased comfort and maneuverability, lighter burdens, and improved human engineering designs. In the first part (Task 1) the mine rescue team's protective needs were defined along with the test methods required to evaluate whether a particular piece of gear met these needs. Task 2 assessed existing gear against performance criteria and standards developed in Task 1. Task 3 consisted of the conceptual design and construction phases of the MRPE program. Special consideration was given to advanced concepts, materials, and equipment.

Jan 1, 1982

By K. L. Paciorek

The aim of the present study was to determine the thermal oxidative behavior of materials used in coal mines, with emphasis on the type and relative concentration of the products, in particular the toxic species formed. To supplement this work and to gain understanding as to the type of products possibly formed and also to assess the limitations and advantages of the various analytical methods used a literature survey of the past investigations performed on the compositions of direct interest to the subject program was conducted. The compositions thus covered were cellulose, polyvinyl chloride, neoprene, urethanes, polyamides, polyesters, polyethylene, epoxy, phenoxy, urea-formaldehyde and melamine formaldehyde resins. The results of this review are compiled in the Appendix. The experimental work consisted of thermal oxidative degradation of 36 materials and 4 composites using a stagnation burner apparatus developed in these laboratories which affords a dynamic system approximating somewhat the conditions encountered in underground coal mines. This technique as employed during this program gave only the relative product concentration at specific periods of the decomposition process, The advantage of this approach is that in this manner screening of materials can be accomplished in conjunction with some assessment of the decomposition rate as influenced by temperature and material composition. Limited static tests were performed using a sealed tube method. The materials studied were grouped according to their compositions. The following were the main groups: (a) polyvinyl chloride-containing materials, (b) neoprene compositions, (c) rigid foams (urethanes, isocyanates), (d) miscellaneous materials (including jute, fiberglass, polyethylene and some articles of unknown composition), (e) coal and fluids (phosphate esters, organic esters, oil-water emulsions), and finally (J) composites. The latter comprised a mixture of a phosphate ester fluid with (a) coal, (b) a representative polyvinyl chloride sample, and (c) a neoprene type composition.

Jan 1, 1972

By H. W. Earnest

This report covers the results of a two-phase study to determine the feasibility of underground disposal of retorted oil shale. Two mining methods, chamber and pillar mining and sublevel stoping, were specified for backfilling. Phase I of the study covered the evaluation of hydraulic, mechanical, and pneumatic transport and stowing systems, individually and in various combinations, and the selection of the most feasible methods. Conveyor transport and stowing and a combination conveyor transport and stowing with pneumatic topfilling were selected for detailed study of phase II. Phase II activities included detailed engineering analysis and design of the selected systems, an engineering economic analysis, and a cost comparison with total surface disposal of retorted oil shale. An extensive literature search was conducted and the bibliography is included in the report. Research done under Contract No. J0265052 by the Cleveland-Cliffs Iron Co. Available for reference at Bureau of Mines facilities in Denver, Colo., Twin Cities, Minn., Bruceton and Pittsburgh, Pa., and Spokane, Wash.; U.S. Department of Energy facilities in Carbondale, Ill., and Morgantown, W. Va.; National Mine Health and Safety Academy, Beckley, W. Va.; and National Library of Natural Resources, U.S. Department of the Interior, Washington, D.C. Order ONLY from NTIS:

Jan 1, 1978

The purpose of this study was to examine the problems of underground coal mining in the United States, and to develop recommendations for an integrated Research and Development Program aimed at resolving these problems. Specific objectives of the study were as follows: ? To identify the existing inadequacies that have adverse effect on Health, Safety, External Environment, and Productivity. ? To identify opportunities for technological advance s to correct these inadequacies. ? To develop an integrated Research and Development Program designed to accomplish the advances identified. Many of the recommended tasks are dearly long range; this is especially true of those for study of future mining systems. However, funding recommendations in this Report are presented for a 5 -year period, since the developments accomplished during this period will undoubtedly be a factor in the formulation of the follow on tasks. Where applicable, the recommended Research and :Development could include development and test of pilot model equipment.

Jan 1, 1970

Two different techniques were used to make measurements of the absolute value of electromagnetic noise in an operating coal mine, Robena No.4, located near Waynesburg, Pennsylvania. One technique measures noise over the entire electromagnetic spectrum of interest for brief time periods. With present instrumentation, the spectrum can be covered from 40 Hz to 400 kHz. It is recorded using broad-band analog magnetic tape, and the noise data are later transformed to give spectral plots. The other technique records noise envelopes at several discrete frequencies for a sufficient amount of tine to provide amplitude probability distributions. The specific measured results are given in a number of spectral plots and amplitude probability distribution plots. The general results are that at frequencies below 10 kHz, power line noise within the mine is severe. Impulsive noise is severe near arcing trolleys, and at lower frequencies near any transmission line. Carrier trolley phone signals and harmonics are strong throughout the mine whenever the trolley phone is in operation. Additional information beyond that included in this report may be obtained from the authors, who are with the Electromagnetics Division of the National Bureau of Standards.

Jan 1, 1974