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Problems discussed and research opportunities identified during the workshop in the major areas of 1) flocculation, 2) flotation, 3) leaching and magnetic separation are summarized below. I. FLOCCULATION Problems Practical problems caused by unintentional flocculation or dispersion were described in the papers that dealt with iron ore processing, selective flocculation, fine coal processing, phosphate processing and potash processing. Ideas generated during the discussions ranged from the very practical suggestion that a conscious effort be made to transfer knowhow from the experienced clay industry to the metals and fuels-from-slimes industry. . . , to the familiar appeals for omnipotent theoretical developments. There was surprising recurrence of some questions in many contexts. Recurring questions are emphasized here rather than commodity-specific problems because their answers would serve a wider clientele usage. There is indeed no objection and some advantage to commodity-specific research, however, provided the proposed project is planned with full cognizance of transferable knowledge in other commodities, and of the possible usefulness of these results in other areas. Research Needs Most of the questions or research opportunities can be classified into three groups: a) water chemistry, b) dewatering, and c) flocculation theory. Other classifications are possible and probably useful. In each group there is a clear need for outwardly esoteric theoretical research a clear application of that work to current practical problems. Higher priority should be given to proposals for theoretical research which explicitly show the expected ultimate usefulness of the result. Likewise, proposals for applied research should demonstrate cognizance of applicable theory. Both of these types of projects could profit from collaboration among industrial, university and government personnel.

Jan 1, 1979

By Yoshio Masuda

Cobalt-rich crust in rich Co, Ni, Mm and Pt will be a potential resources for island country such as Republic. Marshall Islands. This study was conducted for Marshall Islands by the President Kabua?s request. It covers crust resources, CLB mining, processing, and economic estimation, and study concluded feasible veiw.

Jan 1, 1991

By H. E. Wrigley

The boundaries of the oil region in Pennsylvania and New York, as determined by the drill, embrace a much larger extent of territory than is generally supposed, being nearly 200 miles in length from north to south, with an average width of 25 miles, covering an area, within somewhat irregular lines, of about 4250 square miles. After twenty years of development we find these lines practically the same as those laid down by McClure in his geological map of the United States, published in 1817, and denominated and colored by him as the "line of salt," which was found in quantity long before petroleum. The eastern line of the entire oil region lies in a northeast and southwest direction, parallel to and some distance west of the Allegheny Mountains; the south line is substantially one drawn between the western boundary of Butler County and the town of Kittanning in Armstrong County; the west line passes just outside of Butler County, cutting off a small corner of Mercer, west of the towns of Franklin, Titusville, and Warren, into New York State, where it rounds off the end of this long strip in the counties of Allegheny and Cattarangus, and joins the eastern line, near Olean, New York, north of the city of Bradford. (See map.) The eastern line, starting from Kittanning, passes through the northeast corner of Clarion County, the southeast corner of Warren, cutting Forest County through the centre, and reaching the beforementioned extreme northeastern developments near Olean. These lines have been taken broadly to include all territory that could ever possibly come into the question as oil-producing. These lines having been proved by the drill may be considered

Jan 1, 1882

The Emmaville district is located in the northern part of the New England region of New South Wales some 400 miles north of Sypney. Better known for its substantial production of tin and tungsten ores, the Emmaville district has also been the centre of a small and somewhat sporadic production of copper, arsenic, silver, lead and zinc. This production has come principally from three mines-Webb's Silver Mine, Webb's Consols and, to a lesser extent, Pye's Creek Silver Mine.The ores from these mixed sulphide deposits are texturally and mineralogically complex and the problems of beneficiation are rather formidable.GENERAL GEOLOGYThe main rock type of the Emmanville district is a dark, brown to blackish massive siltstone of Permian age which overlies acid volcanics possibly also of Permian age. In places the siltstone gives way to conglomerates and standstones with discontinuous lenses of calcareous sediments (David, 1887).The whole series is folded but because of the massive character of the more expansive siltstone, detailed structure is difficult to delineate.Toward the close of Permian time the area was intruded by a series of intermediate to acid plutonic and hypabyssal rocks. Mineralization within the region is ascribed to the more acid of these intrusives-granodiorite, granite, and quartz-felspar porphyry (Lawrence, 1957, 1960).No intrusive rocks outcrop in the immediate neighbourhood of Webb's Silver Mine though granite occurs two miles...

Jan 1, 1961

By Orlando Romig

PART I-PREPARATION OP METALLIC SINGLE CRYSTALS WITH ESPECIAL REFERENCE TO SINGLE CRYSTALS OP ZINC? As metals and alloys are composed, of, an aggregate of allotriomorphic crystals or grains, each possessing an individual orientation, the physical characteristics of a metal or an alloy are closely related to the properties of the individual crystals. The preparation and study of single metallic crystals are, therefore, matters of considerable importance. The advent of the X-ray spectrograph as a valuable metallurgical tool has magnified the importance of this subject, because the interpretation of some X-ray spectrographs is difficult unless single crystals are used in these studies. PREVIOUS WORK The first paper, as far as the writer knows, on the behavior or preparation of single crystals of metals is by Baker.1 He describes the behavior of extruded wires of sodium and potassium. These wires, when pulled in tension, instead of I showing the usual conical fracture common to most metals, had a chisel-shaped fracture when they were broken. I and II, Fig. 1, have a similar fracture. Baker checked his results by preparing single crystal wires from molten sodium and potassium and observing their properties. He prepared the wires by filling glass tubes, under oil, with the molten metal. The surfaces of the strained wires showed slip bands of remarkable clearness of which photographs are shown in his paper. He concluded that these wires were single crystals and "that the portions of the metal brought into play are cubes. Such cubes, when placed so that a plane through 'two opposite edges was parallel to the axis of the wire, would allow of lateral contraction by faces gliding over one another in one direction only and not in the direction at right angles."

Jan 1, 1927

By Donald M. Hausen

Diamond-bit performance and cost data accumulated by the Bureau of Mines in core-drilling schists reveal significant trends of economic interest. Low-quality, small-size drill bort were the most economical. The percentage of core recovery, type and size of bit, and bit matrix are also correlated with bit performance and costs. Detailed analyses of the factors affecting diamond-bit performances and costs are assessed in the tables, graphs, and discussion.

Jan 1, 1956

By T. S. Mohibatsela, R. V. Ramani, C. V. Manula

The Mineral Engineering Department of The Pennsylvania State University has developed a suite of computer models for anthracite open pit mining (Fig. 1)1 Individual sub-systems have been developed to (a) interpolate geologic field data to obtain coal tonnages, waste volumes, and strip ratios; (b) simulate equipment performance on selected pit profiles to generate data required to choose coal and waste removal equipment; and (c) evaluate selected cost factors to determine either a rate of return for a specified selling price or vice-versa. This paper describes the application of two of these subsystems, namely, the Reserves Model (GEOL) and the Open Pit Materials Handling Simulator (OPMHS), and how these may be applied for the selection of equipment for a prime anthracite mining site.2

Jan 1, 1981

By D. E. Hartman, J. M. Roberts

A detailed study of the temperature dependence of the critical stress, TB . necessary to cause a damping loss of 1.41 x 10-6 g mm per mm3 in pre-strained magnesium single crystals has been carried out in the temperature range 82" to 320°K. Tb is found to be linearly related to the reciprocal of the ahsol~cte temperature in this temperature range. The temperature dependence of the anelastic limit, TA, defined as the stress necessary to form open unidirectional stress-cycle damping loops has been measured between 82" to 320°K. ta is found to be independent of temperature in this range. It is suggested that TA is determined by the stress necessary to activate Frank-Read dislocation NUMEROUS studies1-9 have been reported concerning the details of yielding and microstrain near and below the generally discussed macroscopic flow stress. The work of Kramer and coworkers10-13 is helpful in determining certain qualitative facts. concerning preyield phenomena. The absence of a stress-dependent delay time in annealed copper and aluminum single crystals between 83" and 298 suggests that the preyield mechanism is temperature-independent in this range. This is not sources. The temperature and stress dependence of the effective activation volume (Veff) has been measured in the damping-loop region in prestrained magnesium single crystals. The data suggests that Veff/kT is approximately constant, equal to 2 4.5 sq mm per g in the temperature range 130°to 298°K, and that Veff is almost independent of stress at stress levels greater than 10 g per sq mm. A restricted model is developed to predict the stress (rb) necessary to cause a small fixed damping loss as a function of temperature, effective activation volume, and dislocation density. Various possible dislocation mechanisms controlling TB are discussed. true for zinc, p brass, and iron crystals in the same temperature range, however, since the existence of a stress-dependent delay time suggests a thermally activated preyield mechanism in these materials.10-13 The work by Vreeland et a1.14 confirms the work by Liu et al.ll on delayed yielding in zinc single crystals. A stress-dependent delay time between 82" and 298°K was found12 in prestrained aluminum and copper crystals. These results suggest that the preyield phenomena may be different between prestrained and unstrained or annealed crystals. The temperature dependence of the yield point at 2 x 10-8 plastic strain found by Rosenfield and Averbach3 in annealed copper and aluminum is not in agreement with the delay-time data, unless possibly the delayed yielding experiment only de-

Jan 1, 1964

By Vernon N. Cox

From comments and questions concerning the meaning of USNR, and "why is the Navy in the mining business?" I believe it is worth while to establish the background and purpose of our company. We are a stock company formed by the purchase and reorganization of a company known as the U. S. Natural Gas Corporation. In May 1969, a group of investors with Mr. Robert L. Katz as president and chief executive officer, created United States Natural Resources, Inc., to develop and purposively use our Natural Resources in four areas: 1. Mines and Minerals 2. Forest Products 3. oil and Gas 4. Recreational Lands As final proof that we are not a government organization, I simply state. "We pay taxes." The mining division was formed in October 1969, with the completion of the merger of USNR and Vibration Measurement Engineers, Inc., Of Evanston, Illinois. Throughout the industry we were known as "VME," our company supplied consulting service in the field of seismic energy control, mining consulting and. we operated drilling, blasting and, contracting organizations in several areas of the country. Since that time we have developed and acquired producing properties in Quarrying, Coal Mining and Cement Copper Production.

Jan 1, 1971

By B. W. Dyer

IN 1924, the Crescent Eagle Oil Co., while drilling the salt section of the Paradox formation in Grand County, Utah, encountered a salt that did not appear to be sodium chloride. This salt was analyzed and showed the presence of potash minerals, both sylvite (KC1) and carnallite (KMgC12.6H20). Because of the high potash content of the sample, there was considerable speculation: (I) as to whether the hole had been salted, and (2), if not, the extent, richness, and the depth at which the deposit occurred. The discovery caused a large amount of activity in the area. During the next few years, 68 potash prospecting permits were issued by the Government, 24 under the Act of 1917 and 44 under the Act of Feb. 7, 1927, each including about four sections of land. Several holes, all shallow, were drilled for potash. A number of holes were drilled for oil into the salt horizon and the cuttings collected at the oil wells were examined petrographically and chemically. The shallow test holes were not sufficiently deep to reach the potash horizon and revealed nothing of value, but several of the oil test holes gave some indication of where potash might be found. LOCATION AND GEOLOGY OF DEPOSITS The potassium and magnesium salts have been found in various places from the Denver and Rio Grande Western Railroad tracks about seven miles west of Thompsons, in eastern Utah, to Cane Creek, a tributary of the Colorado Rivera distance north and south of about 35 miles. In this locality, there appear to be five separate deposits: the Crescent Eagle area, which is in T. 22 S., R. 19 E.; the Salt Valley area, in the vicinity of the north-south line of T. 23 S., between R. 20 E. and R. 21 E.; the Seven Mile area, in the eastern part of T. 25 S., R. 2o E.; the Cane Creek area, on the Colorado River, in T. 26 S. and T. 27 S., R. 2o E. and R. 21 E.; and the Salt Wash area, in T. 22 S. and T. 23 S., R. 16 E. and R. 17 E. (Fig. I.) The Crescent Eagle and Salt Valley areas are in the Salt Valley anticline, some of the wells being in the fault graben and others outside. Structurally, the Salt Valley anticline is very complex, and can be described in general terms as a northwesterly plunging collapsed anticline about 15 miles long. In the Crescent Eagle area, the valley graben is about 1 mile wide and the salt probably forms a plug, the apex of which is in the vicinity of the Crescent Eagle well. Owing to the complex structure, there has been every opportunity for flowage in the salt to cause local thinning or thickening of beds. The regular succession of formations in the general area* is: [Cretaceous Mancos Dakota Jurassic Morrison Summerville Entrada Carmel]

Jan 1, 1945

By M. J. Deats

Your article on page 202 of the August 1993 Journal refers. I was surprised to read that this grant was first introduced in 1984 as it was awarded to me (albeit under the auspices of The Institution of Mining and Metallurgy, London) as long ago as 1964, and I spent two very profitable months in Sweden at that time. Training in job-skills * A South African mine is leading the way in providing alternative job-skills to staff in a bid to upgrade services in local communities and create greater economic empowerment. In recent months, 85 employees of the Associated Manganese Mine (ASSMANG) in the Western Cape have learnt skills as diverse as candlemaking, shoemaking, concrete-product manufacturing, and brick production through a newly established community training centre.

Jan 1, 1993

By G J. Butler

Since 2005 BHP Billiton Iron Ore has been working with the consulting company Runge to implement the software XPAC Advanced Destination Scheduler (ADS) in life-of-mine studies. The Mt Whaleback mine, being the single biggest open cut iron ore mine in the world, presents some special challenges in scheduling. The biggest challenge has been the slow run time and difficulty in targeting all ore and waste requirements. The high waste to ore strip ratio means that much of the cost of mining is tied up in waste dumping. It is therefore very important to schedule waste efficiently. At Mt Whaleback there is an additional challenge of managing two types of waste: inert and environmentally sensitive pyritic material. This paper shows how the XPAC destination scheduler is configured to achieve efficient and repeatable waste scheduling results at the Mt Whaleback mine. It also discusses proposed improvements to the process. The overall ore and waste schedule is configured to target mining parameters, crusher feed and grades. The schedule is run in two stages. The first stage is ore mining. The waste that needs to be mined is locked in a sequence. The second stage is the waste scheduling. The waste destination scheduler uses three inputs: source waste parcels locked in a sequence, a haul road and a waste dump block model. The process involves setting some rules for dump progression and haul path selection. These can be validated. The schedule is then run to target the shortest travel time. The results of scheduling are graphical and numeric and can be transferred into many different formats for reporting. The graphical result shows face positions in time that can be used for detailed dump design. The numeric results are used to estimate truck fleet size, fuel consumption, labour and equipment financials. The process has been successful in reducing the project time line, increasing the ability to do more scenarios and increasing schedule accuracy, transferability and repeatability.

Jan 1, 2007

By Pietrobon M. C, Ralston J, Smart St C R

In an on-going study of the chemistry of base metal sulphide flotation, the effect of the inclusion of cyanide in the reagents suite has been studied, with special reference to ore from Pasminco Mining's Elura mine. Cyanide has been variously described as an iron sulphide depressant, a preventor of sphalerite activation and as an activator of galena. In the case described here, the cyanide appeared to act as an enhancer of the galena flotation performance, raising the lead recoveries by 25 per cent but leaving the sphalerite and pyrite responses unaffected. The lead rougher flotation performance with and without cyanide was investigated over a wide range of redox potentials (0 mV to 400 mV SHE). In all cases, the inclusion of the cyanide brought about an increase in the galena recovery and was responsible for a faster rate of galena flotation during the initial stages of the beneficiation. A surface characterisation study (XPS) of the lead flotation stage, with and without cyanide, indicated that the reagent interacted specifically with the galena and pyrite minerals. It was possible to correlate the surface absorption of the cyanide on the lead and iron sulphides with improvements to the flotation performance using the combination of surface spectroscopy and laboratory flotation Testwork.

Jan 1, 1991

By Frank E. Chase

Preventing pillar squeezes, massive pillar collapses, and bumps is critical to the safe and efficient recovery of coal during room-and-pillar retreat mining. To help prevent these problems, the U.S. Bureau of Mines (USBM) has developed the Analysis of Retreat Mining Pillar Stability (ARMPS) computer program. ARMPS calculates stability factors (SF) based on estimates of the loads applied to and the load-bearing capacities of, pillars during retreat mining operations. The program can model the significant features of most retreat mining layouts, including angled crosscuts, varied spacings between entries, barrier pillars between the active section and old (side) gobs, and slab cuts in the barriers on retreat. It also features a pillar strength formula that considers the greater strength of rectangular pillars. The program may be used to evaluate bleeder designs as well as active workings. A data base of 110 pillar retreat mining case histories has been collected across the United States to verify the program. It was found that satisfactory conditions were very rare when the ARMPS SF was less than 0.75. Conversely, very few unsatisfactory designs were found where the ARMPS SF was greater than 1. 5.

Jan 1, 1995

Discussion of the paper of FRANK H. KNEELAND, presented at the New York meeting, February, 1914, and printed in Bulletin No. 97, January, 1915, pp. 61 to 65. B. F. TILLSON, Franklin Furnace, N. J.-I think it may be of interest in respect to the information we have received in regard to the danger of machinery in mining operations, to state that in the particular type of metal miming which the New Jersey Zinc Co. is doing at Franklin, during the past year, although there have been other accidents, that method of miming was free from any accident due to machinery underground. It may give a different light as to the relative degree of the importance of machinery as varying with different types of mining. ARTHUR WILLIAMS, New York, N. Y.-Mr. Kneeland's able presentation of this paper, it seems to me, bears out the suggestion which has been so frequently made that in this country we have a new profession, that of the safety expert or safety engineer, which calling, if properly carried out, would include also questions of sanitation. While Mr. Kneeland was speaking, it occurred to me that perhaps any one, however experi-enced he might be in mining generally, would pass through these mine shafts and these operating rooms, and the things which might cause accidents, which would cause accidents if the right conditions were to occur, would pass by entirely unnoticed by him, but when the safety expert goes into these places he sees these things which he immedi-ately recognizes as being spots of danger and provides means for their elimination.

Jan 5, 1915

By Michael Gauna, Christopher Mark

"Underground coal mining in the U.S. is conducted in numerous regions where previous workings exist above and/or below an actively mined seam. Miners know that overlying or underlying fully extracted coal areas, also known as gob regions, can result in abutment stresses that affect the active mining. If there was no full extraction, and the past mining consists entirely of intact pillars, the stresses on the active seam are usually minimal. However, experience has shown that in some situations there has been sufficient yielding in overlying or underlying pillar systems to cause stress transfer to the adjoining larger pillars or barriers, which in turn, transfer significant stresses onto the workings of the active seam. In other words, the overlying or underlying pillar system behaves as a ""pseudo gob."" The presence of a pseudo gob is often unexpected, and the consequences can be severe. This paper presents several case histories, summarized briefly below, that illustrate pseudo gob phenomenon:• Pillar rib degradation at a West Virginia mine at 1100-foot (335 m) depth that contributed to a rib roll fatality.• Pillar rib deterioration at a Western Kentucky mine at 570-foot (175 m) depth that required pillar size adjustment and installation of supplemental bolting.• Roof deterioration at an eastern Kentucky mine at 1300- foot ( 400 m) depth that stopped mine advance and required redirecting the section development.• Coal burst on development at an eastern Kentucky mine at 1700-foot (520 m) depth that had no nearby pillar recovery.• Coal burst on development at a West Virginia mine at the relatively shallow depth of 1100 feet (335 m) that also had no nearby pillar recovery.The paper provides guidance so that when an operation encounters a potential pseudo gob stress interaction the hazard can be mitigated based on an understanding of the mechanism encountered.INTRODUCTIONThe U.S. underground coal mining industry has conducted mining in multiple seam environments, where the active mining has underlying or overlying old workings at varying interburden distances, throughout its history. Often no serious consequences arise from the multiple seam mining. However, sometime mines have been confronted with hazards from underlying or overlying workings that include localized roof and rib failure, pillar system failures through propagating roof falls and floor heave, and also pillar bursts."

Jan 1, 2016

By Pradhan GK

Blasting is one of the most important operations involved in surface coal mining. The removal of over-burden waste in surface coal mines of India had experienced many improvements in terms of blasting, explosives selection, blast design, equipment selection, deployment. etc. Two case studies of very large surface coal mines have particular importance in their blasting operations. Both these units have been equipped with large capacity excavating machines, hauling units and also have some difficult mining situations. Blasting is done in benches in close proximity to human dwellings and over coal seams developed by underground methods with problems of high wall stability etc, as well. The various steps taken to improve the blasting operations ensure smooth operation of the equipment to meet the targetted coal production.

Jan 1, 1991

"Desde 1950 en el Perú, el examen pre-ocupacional es un requisito para la inserción laboral dentro de la industria minera. Es por ello que la empresa se encargaba de la realización de la evaluación directamente. Posteriormente se designó dicha labor a un personal no facultativo, conllevando riesgos de salud futuros para el trabajador y por ende, a la producción de la empresa. En este sentido, el presente texto señala algunos de los aspectos de política preventiva de salubridad, donde sea el profesional médico, quien realice una promoción de salud y diagnóstico precoz de la enfermedad, protegiendo así la vitalidad del trabajador. Entre las principales funciones del personal médico a realizar tenemos: las contínuas visitas médicas al lugar del trabajador, desarrollar una permanente capacitación de actividades de higiene industrial, delimitar enfáticamente una orientación preventiva de su trabajo, etc. De otro lado, el trabajo muestra una descripción del formato médico (datos, historia ocupacional, antecedentes patológicos, sintomatología, examen clínico, inmunizaciones, clasificación de actitud) que debe considerar el examinador, para obtener un conocimiento conjunto del estado de salud del postulante y potencializar las capacidades del trabajador para la industria minera. De tal forma que se logra integrar en un solo documento médico, los resultados de los exámenes y se prescinde de la necesidad de contar con grandes archivos, facilitando el seguimiento de los casos."

Jul 20, 1957

By James N. Prudden

Measurable physical characteristics of placer deposits include geological, geomorphological, sedimentological and mineralogical features which produce the complimentary ingredients with which one can formulate an economic evaluation of these complicated deposits within the confines of a well established geological model. Heavy mineral suite composition and character will change downstream from the provenance area and will compliment the related depositional environment. Careful attention to gold particle characterization during the exploration phase can indicate new source additions, enhance deposit evaluation methods and greatly assist in maximizing metallurgical efficiencies. Failure to recognize and measure these important features very frequently leads to frustrated and unrewarding placer evaluation goals. Increased general acceptance of sedimentology in the gological appraisal of ore bodies has progressed into the science of clastic sedimentalogy using measurable parameters to evaluate minable units. This branch of geology has developed as a tool in locating, defining, and mining alluvial concentrations of valuable heavy minerals. The repeatedly successful application of this valuable tool in conjunction with other classical geological methods can be directly related to the development of a geological model which formulates the distribution of detrital gold. This use of multiple geological techniques permits the transfer of routinely derived data to management. Standardized nomenclature permits the transmission of uniform information thereby promoting credible property evaluation. This approach enables organizations to critically assess large numbers of potential mining targets for definitive feasibility studies. Sedimentology must play an integral role in the evaluation of any alluvial deposit. The sampling problems associated with particulate gold are well known and frequently cause perplexing evaluation problems. Consequently, properly directed and executed

Jan 1, 1987

By James H. Aase

Selected glacial lake clay deposits in Minnesota were sampled, tested, and evaluated to determine their suitability for use as a bonding agent in iron ore pellet manufacturing. Preliminary tests conducted on clay samples obtained from five ancient glacial lake basins identified the clays in the Lake Agassiz glacial lake basin near Cook, Minn., as having the greatest bonding potential. An auger drilling program was conducted to obtain substantial quantities of representative material for detailed testing. The drilling indicated the presence of large clay reserves in excess of 500 million tons within the 12-square-mile area investigated. Bench scale tests indicated that the bonding properties of Cook area clays, when activated with relatively small quantities of sodium carbonate monohydrate (Na2C03?H2O), imparted excellent strength characteristics to iron ore pellets. Larger scale continuous pelletizing tests were made to confirm the bench scale results. These tests indicated that use of 1 percent activated clay alone as binder gave the iron ore pellets an overall strength slightly lower than with 0.75 percent bentonite, considered the industry standard. Use of 0.5 percent activated clay plus 0.5 percent bentonite produced better pellet strength qualities than use of 0.75 percent bentonite alone, without increasing the silica plus alumina content. The data from both bench scale and larger scale continuous tests suggest that the Cook, Minn., clays can be utilized after activation either alone or in combination with bentonite at an economic advantage over present pelletizing practice with bentonite.

Jan 1, 1968