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By Thornton L. Neathery

The low-grade talc deposits in Tallapoosa County, Alabama, are associated with a mafic-ultramafic rock complex that is part of a widely distributed schist and gneiss group. These rocks form a synform structure overlying Inner Piedmont lithology. Paragenetic sequence of the Tallapoosa talc is interpreted as enstatite-anthophyllitetalc. Talc occurs as massive boulders formed by the alteration of enstatite-anthophyllite and as finely disseminated discrete particles in the enclosing saprolite matrix. Weathered rock reaches depths as great as 60 feet. The quality and quantity of the talc, however, are variable. Mineral analyses of the talc-bearing samples, by petrographic grain count, indicate a talc content of 16 to 26 percent. Most of the talc occurs as plates or scales that are moderately stained with limonite. Fibrous talc also occurs in the deposits and is often mistaken for anthophyllite asbestos which is intimately associated with the talc. The size, shape, and occurrence of the talc deposits precludes any method of min¬ing other than open-cut. A small-scale mining operation began in the district in 1969. Potential capacity of the operation is 5, 000 tons per year. Inferred reserves, based on field investigations, are placed at approximately 8 million tons. Approved for publication by the State Geologist, Geological Survey of Alabama.

Jan 1, 1970

By Thomas Van Riper

Newmont Mining Corporation started as one man's investment vehicle. William Boyce Thompson, Newmont's founder, was already a millionaire many times when he incorporated his existing Newmont company in Delaware in 1921. The initial stake in the company was $8 million in capital contributed by Thompson and several close associates. In its infancy the company was truly a holding company. It did not operate or manage any properties. This situation changed drastically over time. By 1939 Newmont was actively mining 12 gold mines in North America. The following year, the first copper mine that Newmont ever managed directly, came into full production in South Africa. The period after World War I1 was a glorious one for Newmont. Plato Malozemoff took the helm of the company, and expanded its operations over the next 30 years into copper in Arizona, oil and gas in the U.S. and the North Sea, into domestic coal and thankfully, into significant gold operations.

Jan 1, 1989

By Babu K. V., Samyukta P.

The energy demand in India is expected to show increasing growth in the next few decades. The oil companies in India are revamping the existing oil refineries as well as constructing new refineries across the country to meet the energy demands. Most of the refineries in India are located along the coastal region because of the ease of transporting crude materials. Considering the criticality of the structures as well as soil conditions in the coastal region, pile foundations are used in refinery plants. In India, non-displacement piles in the form of bored cast-in-situ piles are used to support structures. In a few circumstances, displacement piles in the form of driven cast-in-situ piles are also being used to support critical structures. This study presents the performance of non-displacement and displacement piles for similar ground conditions at the same project location. The pile load test results have shown that the settlement observed for displacement piles is lower than compared to non- displacement piles for a given loading and soil conditions. This shows that the performance of displacement piles is slightly better in comparison with that of non-displacement piles.

Sep 1, 2022

By Michel Boisvert

Noranda Metallurgy is presently completing construction of the new Noranda Converter (NCV) at its Home Smelter in Rouyn-Noranda. This capital investment of CDN$56M is the continuation of the Emissions and SO2 Reduction Program that was initiated in the late 1980s with the acid plant for Reactor off-gas treatment. The Patented Noranda Converter was developed and pilot tested at the Home Smelter in the early 1990s. The project will replace the Peirce-Smith Converters and enable sulphur fixation to be 'increased from 70% to over 90% by 2002 with an accompanying reduction of dust emissions to the atmosphere. The construction site is an extension of the present Noranda Reactor area. A number of existing facilities including the acid plant and process air supply were used to minimize the capital cost of the project. This paper provides a brief history of the Noranda converting process, the Home Smelter Emissions and SO2 Reduction Program, ,project implementation and construction, a description of the different facilities, and preparation of human resources for start-up.

Jan 1, 1998

By John D. Ridge, Betty S. Moriwaki

The significant chromite producers listed in Table I11 are not major steel producers, with the exception of the USSR. After manganese, chromium is the most important alloying metal in steel. It would not be surprising to find a direct relationship between steel production and chromite imports. The precise connection is concealed by the other uses of chromite and the grades of steel produced by the various countries involved. In addition, the amount of ferrochromium made for export must figure in any calculation. Norway, a producer of considerable amounts of ferromanganese, imports significant quantities of chromite for ferrochromium manufacture. Most of the ferrochromium is exported to European steel- producing nations. Sweden imports only half as much chromite as Norway but makes far more chromium-bearing steel. Thus Sweden has far less ferro-chromium for export, although it supplies about 2000 tons per year to the U.S. and probably some- what more to such chromite-poor steel producers as Germany and Belgium-Luxemburg.

Jun 1, 1955

By A J. Morrison, K Demir, J Kohmuench, K Runge, C Evans

The Eriez HydroFloat® is a flotation device capable of recovering significantly coarser and lessliberated particles than is possible using a conventional mechanical flotation cell. Originally developed for industrial and bulk mineral beneficiation, the HydroFloat® is attracting increasing interest as a means of increasing the required grind size for metalliferous ore flotation. Doing so would reduce the costs of processing complex ores, either by decreasing the energy required to grind the flotation feed or by increasing the throughput achievable with a given comminution circuit. Processing coarser particles would also result in coarser waste streams, potentially improving the mechanical and hydraulic performance of the waste dams that they are sent to. Recent work at pilot – and industrial-scale has proven the potential of the HydroFloat® technology to achieve these gains in metalliferous applications. However, in order to realise the full potential of the HydroFloat® technology, it is necessary to understand not just its performance but also the drivers for that performance. Doing so will allow the design and operation of HydroFloat® devices to be optimised for different ores and applications. For this work, a HydroFloat® pilot rig was deployed to a coppergold plant in Australia and was used to investigate the effect of stream and operating conditions for treating the tailings stream of one of the plant’s rougher flotation cells. Under each set of operating conditions, samples were taken of the HydroFloat® feed, tailings and concentrate streams, and processed to yield the grade and recovery achieved by the device. At the same time, the bubble size and bed behaviour inside the device were measured. This paper presents preliminary relationships observed between the operating conditions and the performance of the HydroFloat® cell, and thus suggests a range of possible drivers for the measured coarse particle flotation performance.

Aug 24, 2022

Mining was the first economic activity carried out in Cuba, by the colonial conquerous, i.e. gold extraction from rivers and use of asphalt to calk their ships; however, due to different historic reasons only a limited development took place in this field during the colonial domination. During the republican period beginning early in this century, other interests lead to a larger scale exploitation of some known deposits. From the beginning of the century up to the triumph of the Revolution in 1959, not less than the following figures were extracted of some Cuban minerals: Refractory Chromium 3,300,000t Manganese 7,650,000 t Copper 9,000,000 t Iron 22,000,000 t Nickel 150,000 t (Ni oxide and sulphide These productions were practically directed to cover the demands of the U.S., industry and some-times these Cuban ores were almost the sole suppliers of the market.

Jan 1, 1978

In 2007, a total of 7,199 sand and gravel mining operations reported employment to the Mine Safety and Health Administration (MSHA).1 ? Sand and gravel mines were the largest mining sector, comprising 48.4% of all mining operations. ? Sand and gravel mines were found throughout all 50 states and Puerto Rico.

Aug 1, 2009

By Lloyd R. Nelson

Experimental results of three-phase mixing in a physical model of a CCRL for metals refining are presented. The system was operated above a critical lower liquid height-to- width ratio (H,/W) of unity, with adequate bottom gas injection through a line of central, single tuyeres (Q,/A = 7.5 cm/min, or c = 17 W/m3) to sustain levels of interphase transport considered appropriate to an industrial pyrometallurgical refining operation. The application of a thermal tracer technique to elucidate both longitudinal mixing and interphase heat transfer is discussed. The results indicate that even under conditions of significant bottom gas injection, it should be possible to maintain acceptably low longitudinal mixing 1 (D, < 20 cm /s and D,/uL < 0.1) in the CCRL. Interphase mass transfer coefficients of the order of 0.004 cm/s are predicted from the measured interphase heat transfer coefficients (h = 1.3 to 2.0 kW/m2K), using the heat and mass transfer analogy. Adequate rates of rehning are predicted for an industrial CCRL operated under such conditions.

Jan 1, 1995

By D. Harrington

Most of those in the Health and Safety Branch, Bureau of Mines, necessarily participate in activities associated with essentially all phases of the mineral industries, including coal and noncoal mines, quarries, smelters, metallurgical plants, and various petroleum operations. One of the strictly war activities of the branch - the Explosives Control Division, which administers the Federal Explosives Act of December 26, 1941 - has functions that require contacts not only with nearly all phases of the mining and allied industries but also with those engaged in scores of other occupations that manufacture, store, use, or possess explosives, or many of the ingredients of explosives. The field men of the Health and Safety Branch (approximately 300 in number) Are occupied full time in health and safety activities and annually make thousands of contacts with people in the mineral industries as well as the plants in which they work. From these they formulate several thousand written reports containing sources of thousands of conclusions and recommendations aimed at reduction of health end safety hazards in these industries. Although such activities have been greatly increased during the war and immediate pro-war periods, they have been in effect to a considerable extent since the Bureau of Mines was created in 1910.

Jan 1, 1944

By Alberto Encinas

El presente texto describe el proyecto de explotación racional realizado en 1977 en la isla aurífera de Madre de Dios. El objetivo de este trabajo es justificar la adquisición de una retroexcavadora mediante un crédito del Banco Minero del Perú como una contribución al propuesto desarrollo de la minería aurífera.

May 1, 1978

By William H. Schiffbauer

This paper details the computer hardware and software integrated to provide computer-assisted control and monitoring of four different coal mining machines. The backbone of each system is a U. S. Bureau of Mines integrated distributed microcomputer control network called BOM/NET. The network provides connections for intelligent sensors and systems that provide for navigation, diagnostics, and computer control. Many different computer systems using various operating systems (including RMX I, UNIX, VXWORKS, DOS and DCX51) have been connected to the network and each have had complete network functionality. A description of the network&apos;s integration to Joy&apos; 16CM, a Joy 14CM, a Jeffrey 102, continuous mining machines, and a custom built auger machine is provided. The networks for the Joy 16CM, the Joy 14CM, and the Jeffrey 102 have been installed and extensively tested at the Bureau&apos;s surface test facility. The Jeffrey 102 system has also been tested in a highwall coal seam. The Joy 14CM will soon be tested underground.

Located 350 km west of Sydney and 20 km outside Orange, NSW, lies the Ridgeway Gold Mine û NewcrestÆs flagship Underground Gold Mine. Key to success at Ridgeway has been the fast tracked development of the 3.8 km, 1 in 5.3 conveyor decline which houses the 850 t/hr conveying system feeding the dedicated Ridgeway Concentrator, built adjacent to the existing Cadia Hill Concentrator. Eroc was contracted to develop the steep conveyor decline, drawing on its personnel and experience from past metalliferous, tunnelling and coal mining projects to complete the ambitious schedule within 12 months. This paper deals with the complexities and experiences in safely delivering what is understood to be one of AustraliaÆs steepest declines of any substantial length in a metalliferous mine.

Jan 1, 2002

By K. Y. Vasioutchkov, Y. F. Vasyuchkov, B. M. Vorobjev

In general a term "unconventional mining or "non-traditional mining technology" getting more and move familiar to the mining engineering media. There are several alternating terminological combinations such as "in situ mining", "borehole mining", "shaftless mining", "mineless mining", "geotechnology" etc.; specific terms denote particular method of unconventional mining technology: "underground coal gasification in situ", "underground coal combustion in situ", "borehole hydraulic coal mining" and others. Principal scheme of unconventional coal mining technology is shown in [Figure 1:] One of the greatest potential for coal utilisation during the beginning decades of on coming cetury is the synthetic fuel-gas derived from coal as a product of coal gasification. It is quite logical to enrich this gas before burning it with natural gas, that is methane, contained in coal measures. Thus it is reasonable to suggest a new concept of unconventional coal mining and utilization technology featuring integrated methane drainage with coal-gas combined cycle. Proposed unconventional technology of coal mining is characterized with: - opening up a coat deposit through boreholes, drilled from the surface and used for coalbed methane drainage as well as for coat gasification in situ; - aggregation of methane producing and coal gasification station on mining side with thermo power plant on the electric power generation side in one integrated industrial enterprise. The further improvement of the conventional coal mining technologies both surface and underground could give only insignificant results in economical, ecological and social aspects, but would not be able to provide basic requirements of the XXI-st century. Significant increase in economical efficiency, cardinal humanization of coal mining and basic improvements in environment protection would be achieved through introduction and implementation of innovative or unconventional coal mining technology. These considerations are applied on both coal production and coal utilization sides as far as coat based energy generation is concerned. Now a general opinion is widely spread that an application in the same manner of the traditional technologies of coal mining and electric power generation would inevitably cause further irreversible damage of the global eco-system, notwithstanding the certain environment protection measures being taken. Keeping the recent pace of the eco-system degradation the whole our civilization would be in danger. Thus the solution of this problem is to be found in developing, promoting and implementing in industry unconventional coal mining and modern advanced clean coal technologies. Coal reserves with favourable conditions at shallow depths are -being rapidly depleted in all countries with developed coal industry. So in nearest future more coat will be mined from deeper levels with higher operational expences and with lower labour productivity. For example in Russia only 20% of proven coal reserves can be specified in quality as easy mined reserves, i.e. coal reserves with a good minability. Unconventional (borehole in situ) coal mining enables us to mine difficult coal reserves, deposited under unfavourable geological conditions with higher economical and socio-ecological efficiency than that in conventional coal mining, in view of these the basic principles and concepts of coal mining and coal utilization for energy generation should be reconsidered taking into account the latest achievments in underground coal gasification/combustion, coalbed methane extraction, clean coat technology and advanced developments in environmental engineering. The authors have developed a new concept of ecologically clean and resource saving coal-gas electricity, protected by a patent of Russian Federation (1995). The main principles and technological features of these conceptual technologies are explained hereupon. It should be a break through into a coal mining technology of new generation, which is known as unconventional coal mining technology. Under current global energy policy, transection to the new generation of coal mining technology is inevitable. Now we are standing at the treshhold of the coat&apos;s regeneration based on integrated unconventional coal mining and innovative coal fueled electric generation technologies.

Feb 24, 1997

By Marwan M. Mohammed, Hani S. Mitri, Wilfrid Comeaul, Baoyao Tang

In many parts of the world, rockbursts have become a major problem of mining at depth. As orebodies are being mined deeper, rockburst phenomena have become familiar to deep hard rock mines. Rockbursts are generally characterised by sudden release of energy in a volume of highly stressed rock, which can cause local violent failure of the rock mass around the opening. One method of controlling these failures is to precondition the rock mass by detonating fully confined explosive charges at the appropriate locations. This method known as destress blasting, was first tried in the deep South African gold mines (Roux et al., 1957), and was widely used later in Canada, United States, France, Poland and Japan.

Jan 1, 1999

By Robert E. Gray

The vat leaching operation at the Yerington Mine was started in October, 1953. The original plant facilities consisted of primary and secondary crushing, eight leaching vats, precipitation launders, sulfuric acid plant and the necessary maintenance, warehouse and administrative facilities. By 1961, 35,000,000 tons of oxide ore had been removed from the mine exposing the underlying sulfide ore body. A 5,000 ton per day concentrator was constructed and put into operation to treat the sulfide ore in November, 1961. The original crushing plants were used for both oxide and sulfide ores. By adding a third crushing shift for six days per week, the treated ore was increased from 12,000 to 17,000 tons per day. To balance the oxide and sulfide ore reserves, the concentrator was expanded to 13,500 tons per day in 1967. Again, no additional crushing facilities were added. It was anticipated that the treatment rate of oxide ore would be reduced from 12,000 to 9,000 tons per day. Instead, the addition of two crushing shifts per week, and improved operating procedures, increased the treated ore to 26,500 tons per day, 13,000 tons to the vat leaching and 13,500 tons to the concentrator.

Jan 1, 1975

By Christina Pomee, John Parianos

"TOML’s ISA Contract comprises six areas (A-F) that span from 118° to 152° W and from 7° to 15° N or over 70% of the CCZ.During a 2015 exploration cruise, TOML scientists found that the a logging system developed by ISA (2010) was able to be adapted and enhanced, to describe in some detail the varied morphology of nodules both within the TOML areas and between them.The shapes and sizes of nodules seen were then found to relate to substrate type and setting, and thus likely thickness and long-term stability of the geochemically active layer. Consideration of the various processes that might influence growth helps constrain nodule formation further. The nodules effectively record the long-term geochemical conditions that lead to their formation.ISA (International Seabed Authority), 2010. A Geological Model of Polymetallic Nodule Deposits in the Clarion-Clipperton Fracture Zone and Prospector’s Guide for Polymetallic Nodule Deposits in the Clarion-Clipperton Fracture Zone. International Seabed Authority Technical Study: No. 6 ISBN: 978-976-95268-2-2"

Jan 1, 2017

By Charles Jones

IN the winter of 1902, while occupying the position of mining and examining engineer for the Mountain Copper Co., Ltd., of Keswick, Cal., I had occasion to discuss with the General Manager, among other things, the question of the enormous waste of sulphur in smelting cupriferous, pyrite ore, and to cast about for means to utilize this waste or to render the fumes innocuous to vegetation. The decreasing rate of production of California farms, the consequent need of fertilizers, and the opportunity thus offered to utilize large quantities of sulphuric acid in the manufacture of superphosphates naturally brought the subject to the practical and commercial side of phosphates. I was informed that the company had made efforts to find phosphates in the West, without success. I advised as a start placing inquiries for phosphate deposits on the Pacific coast in the current mining ,journals. This was done, with the result that in January, 1903, from an advertisement in the Mining and Scientific Press we got track of a deposit in Rich county, Utah, through T.J . Wilson, of the Southern Pacific railroad in San Francisco. As soon as snow in the mountains would permit, in May, 1903, I undertook an examination of the property, with the result of recognizing the importance of the find, in spite of its lack of facilities for transportation at a commercial figure. On June 15, 1903, I concluded my report by saying, "This may be one of the world&apos;s deposits of phosphates." On Nov. 17, 1903, I concluded my report for the season in the following words : " I have now no hesitation in saying that I believe the Carboniferous formation so largely developed in the Wasatch mountains of Utah and the mountains of the Great Basin will prove to be one of the greatest storehouses of phosphoric acid in the world."

Jan 10, 1913

By J. W. Sandelin, L. S. Birks

The group five metals, vanadium, niobium, and tantalum all show cold-rolled textures of {100)(011) and {112)(0ll) with a preference for the (100) in vanadium and niobium and for the {112) in tantalum. Recrys-tallization texture of (100) and (111) was reported1 for vanadium after annealing (no temperature stated). For tantal~m ,~ annealing below 1200°C strengthened the (112) texture but the (111) texture increased and was predominant as the annealing temperature was raised to 2500°C. Annealing niobium up to 1100°C strengthened the ( 100) texture and developed a weak (111) texture.&apos; In the present work niobium has been annealed up to 2000°C. Nearly 70 pct of the grains showed {111) texture with only a weak (112) component and an insignificant (100) component remaining. In addition, double-crystal rocking curves were used to follow the increase in crystal perfection of the grains with increased annealing time. Material and Treatment. Samples i by 4 in. were sawed from & -in.-thick cold-rolled niobium sheet obtained from Wah Chang. Chemical analysis of the material showed it to be 99.4 pct pure with tantalum as the major impurity. Individual pieces were annealed for 2, 15, 30, and 60 rnin in a vacuum of 10&apos;* Torr using an rf generator. They were etched until the grain boundaries were well-defined, Fig. 1. Average grain size varied from 1 mm for 2 min annealing to 2 mm for 60 rnin annealing. Experimental Results. Preferred Orientation. The orientations of 97 of the 117 grains in the specimens of Fig. 1 were determined by back-reflect ion Laue patterns. A General Electric 10-cm-diam cylindrical camera was used rather than the conventional flat camera in order to record more of the low-index spots. The method proposed by Forest, Barton, and schieltz4 was used to transform the cylindrical film patterns to standard stereographic projections. Table I gives the compilation of data. Even 2 rnin anneal at 2000°C is sufficient to yield a strong (111) preferred orientation, and the percentage of grains with this orientation increases steadily with annealing time at the expense of all other orientations. Crystal Perfection. X-ray topographs were taken of each specimen in both the (111) and (112) orientation using the method described by Birks and Grant.&apos; As the anneal time increases, the grains become larger and the individual reflections become slightly more uniform in intensity, indicating an increase in crystal perfection. For a more quantitative measure of crystal perfection, it was necessary to measure the double-crystal rocking curve. The spectrometer employed was a Gaertner instrument of Compton design. LiF was chosen for the first crystal because the (400) reflection with d spacing of 1.05 AU is a good match to the (222) niobium reflection with d spacing of 0.95 AU. CuKp radiation was used in order to further reduce the d spacing mixmatch correction.&apos; A variable aperture was placed between the LiF and the niobium specimen so that a single grain or even a small portion of a grain could be examined. Fig. 2 shows typical rocking curves for the four annealing times. For the 2-min specimen, a single peak is observed with 10&apos; of arc full-breadth at half maximum. As the annealing time is increased to 15 or 30 min, several sharper peaks of 40 to 80" breadth can be seen within a single grain. After 60 rnin anneal only a single peak of about 30" is observed. Table I1 shows the corrected rocking curve breadths and the dislocation densities, ND. The latter were calculated from the equation7 where W is the corrected rocking curve breadth at half maximum in radians and b is the effective Burger&apos;s vector. For (110)(111) slip in niobium, b is 2.86 AU. Discussion. The annealing of cold-rolled niobium at 2000°C causes rapid preferential growth of grains with {ill} orientation. After only 2 rnin annealing time, 35 pct of the grains have the (111) orientation, and after

Jan 1, 1968

By Chen Song

Keywords: Co3O4, Cobalt Compounds, Morphology, Urea, Homogeneous Precipitation Depending on experimental condition, precipitation from cobalt nitrate and chloride solution in the presence of urea yield dispersed cobalt compounds with different chemical compositions and morphologies. The effects of concentration of cobalt solution and urea, agitation, on precipitation morphology were investigated experimentally. Generally in closed systems the particles are identified as cobalt (II) basic carbonate with needle type shape. In open system, spherical and plate-like precipitations of cobalt (II) basic cyanate are formed. The chemical formula of cobalt compounds was confirmed. They are CoII,III(OH)0.83(CO3)0.49 Ay?0.14 H2O (in tightly-capped reactor: A stands for NO3?, Cl?; y[A]molecular weight < 12.9) and CoII,III(OH)0.83(NCO)XAy?0.14 H2O. (in open reactor A stands for: NO3?, Cl?; 42 x + y[A]molecular weight < 44.82). The main reason was that the primary particles had different chemical compositions for the effects of the different kinds of anions and stoichio-chemical compositions of the primary particles. The effect degree of the anions depended on the co-existing anion radius in the reaction solution. According DTA-TG analysis of the cobalt compounds, the latter particles transform to Co3O4 powders on calcining. The shape of the Co3O4 particle with porous character has inheritance with precipitation. In this paper, it concludes that the particle formed by the principle of nucleation-aggregation in aqueous solution. The process of aggregation has played an important role in formation of particles. During calcination, the aggregation would be destroyed partly.

Jan 1, 2005