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By Anish Kumar

Keywords: Ultrasonic velocity, Poisson?s ratio, Elastic constants A new correlation has been established between two independent elastic properties, ultrasonic shear wave velocity and Poisson?s ratio, in a wide variety of isotropic solid materials, such as pure metals, ceramics, polymers and intermetallics. It has been shown for the first time that Poisson?s ratio decreases with increase in elastic moduli, E & G and ultrasonic velocities. This new correlation between two independent elastic constants may lead to the reduction in independent elastic constants for isotropic solid materials from two to one, at least for a given alloy system with different microstructural conditions.

Jan 1, 2005

By L. S. Darken

IN the study of reactions occurring in liquid iron, alone or in contact with a liquid oxide or slag phase, it has been found that the experimental data over a limited range of concentration can in some cases be repre-sented satisfactorily by the simple equilibrium expression K - (p1)p1 (p2)p2 . (R1)r1(R2)r2 . where (P) denotes the concentration of a product and (R) the concentra-tion of a reactant in the reaction r1R1 + r2R2 + . . . Some of the reactions for which it holds are listed in Table 1. For others, however, the simple equation apparently does not hold. This has been attributed to an improper method of expressing concentration (for instance, weight per cent instead of mol fraction); or it has been supposed that the solutions are not ideal in the sense that the activity of a com-ponent is not proportional to its true mol fraction, But it may be that the problem has been oversimplified by neglecting some molecular species actually present; that is, by considering only the ostensible simple com-ponents and thus leaving out of account possible compound formation. It is the purpose of the present paper to point out how, in a group of related cases, a reasonable consistent assumption relative to the presence of a compound makes it possible to express the experimental data satis-factorily by the simple equilibrium expression when this compound is taken into account, and to bring into harmony data referring to different reactions in liquid iron. There are several a priori reasons for believing that solutions in liquid iron should not deviate far from ideality, provided that the concentration of solute is not too great and is expressed in proper terms. The factors that commonly lead to nonideality in systems at ordinary temperature as ionization or the occurrence of polar and nonpolar molecules-are presumably less effective in metal and in slag systems at high temperature. Again, the type of equation commonly used to express the value of

Jan 1, 1940

Alabama ranked 19th in the Nation in nonfuel mineral value1 in 1994, down from 18th in 1993, according to the U.S. Bureau of Mines. The estimated value for 1994 was $576 million, a 2.5% increase over that of 1993. This followed a 3.5% increase in 1993 over that of 1992. The State accounted for a little less than 2% of the U.S. total. Nonfuel mineral production in Alabama consisted entirely of industrial minerals; no metals were mined in the State. Bauxite materials mined in the State are a natural mixture of bauxitic clay and bauxite having very low iron oxide content and are primarily used to make refractory (high temperature resistant) products, rather than in the production of primary aluminum. In descending order of dollar value, the top four mineral commodities produced in Alabama were crushed stone, portland cement, lime, and construction sand and gravel. These commodities accounted for almost 88 % of the State's total non fuel mineral value, while crushed stone and portland cement together represented almost 65 % of the total. In estimated mineral production for 1994, Alabama remained first in common clays and first of only two States that produced bauxite; third in lime, kaolin clays, and fire clays; seventh in portland cement and salt; and was one of the top seven States that produce bentonite clays. The State dropped from third to fifth in masonry cement. Production of talc and pyrophyllite resumed in 1994. Compared with 1993, the value of crushed stone, lime, construction sand and gravel, common clays, kaolin clays, fire clays, bauxite, and talc and pyrophyllite increased. Decreases occurred in portland cement, masonry cement, industrial sand and gravel, and dimension stone.

Jan 1, 1995

By H. R. Pierce

A gas well has a certain definite capacity to deliver gas from the gas sand through the producing string of pipe. This capacity depends upon the pressures in the sand; that is, a well will deliver gas at a rate of flow which is determined by the formation or "shut-inn pressure in the sand and the back pressure at the face of the sand in the well. The three factors, rate of flow, formation or "shut-in" pressure, and the back pressure, for a given well, can be written into a fundamental relation which is strictly applicable only to that well. This relation can be used to determine the capacity of the well to deliver gas from any formation pressure against any back pressure held at the f ace of the sand in the well. Studies have been made of the deliveries of 400 gas wells operating under different conditions of pressure, Most of the wells which have been studied are in Osage County, Okla.; however, several representative studies have been made on wells in southern Louisiana, southern Texas, the Texas Panhandle, and West Virginia.

Jan 1, 1929

Despite the media's use of the mining industry as a whipping boy over its perceived attitude towards the environment, the facts remain that the only legislated requirement in the SA Statute Books for any form of environmental impact-assessment prior to development is to be found in the Minerals Act in the form of an EMPR. Not only is our industry complying with this requirement, but moves are afoot to set up environmental management systems for existing operations in preparation for seeking accreditation under ISO 14001 when published towards the end of this year. On how broad a front are we advancing? ? Is the industry equipped to handle these challenges? ? Does it have the determination to overcome its problems? ? Do we realise that failure may mean the loss of markets overseas to competitors who can meet the international standards? ? Where are the shortcomings and when must our efforts be focussed?

Jan 1, 1996

By R. C. E. Bray, Peter Price

"The property of Pamour Porcupine Mines, Limited, is in the eastern Porcupine area, about 12 miles northeast of Timmins. It covers parts of lots 3-6 (inclusive), cons. 5 and 6, Whitney tp., Cochrane district, Ontario. It is an amalgamation of the old La Palme, Three Nations, and Porcupine Grande properties.The first discovery on the Pamour was made in 1911. During 1911 to 1914 a small shaft was sunk on the Three Nations vein to the 200-foot level and a 100-ton stamp mill was put in operation, but only a small production was achieved. The property remained idle from 1914 to 1923. In 1924 some diamond drilling was done along the Keewatin-Timiskaming contact with some encouraging results, but the gold mineralization encountered was too low in general at the price of gold then prevailing to warrant further · work. The increase in the price of gold revived interest in the area, and the above noted amalgamation was effected in 1934. Options were taken and successively dropped by two large mining companies. Following this, exploration both on the surface and underground was started by Quebec Gold Mining Corporation, Limited. Diamond drilling in the early part of 1933 showed considerable ore in conglomerate and greywacke to the east. In the middle of 1935 Noranda Mines, Limited, assumed control and management. A new shaft was sunk and the property was ·equipped with a mill having an initial capacity of750 tons a day. This was subsequently enlarged to 1,500 tons a day.From the commencement of milling (May 16, 1936) to the end of 1946, 5,025,545 tons of ore having an average grade of 0.1327 oz. a ton ($4.64 at $35 an oz.) have been mined and milled."

Jan 1, 1954

By A. H. Winckers

"CAMIRO, The Canadian Mining Industry Research Organization, formerly known as MITEC, is a collaborative research organization of Canadian Mining Companies. It is comprised of Exploration, Metallurgical Processing and Mining Divisions.The Metallurgical Processing Division (MPD) has the mandate to contribute to the profitability, competitiveness, safety and growth of the Canadian mining industry by improving the efficiency and effectiveness of mineral processing and extractive metallurgy in an environmentally conscious manner through the development of innovative technology by managing cooperative industry focused research programs.Current membership includes about ten Canadian mining companies. Past research has largely focused on base metal mineral processing. The Division wants to expand its research base to include all areas of mineral processing and extractive metallurgy.Past performance and plans for the future will be highlighted in the presentation."

Jan 1, 1998

By Alla D. Mah

No experimental heat-of-formation value has been reported in the literature for cerium sesquioxide. The heat of formation of bismuth sesquioxide has not been determined in recent years, and the older value was subject to large uncertainty. Accordingly, the heats of combustion of cerium sesquioxide and bismuth metal were measured by the Federal Bureau of Mines. The heats of formation were: ?H°298.15 = -427.01 ± 0.70 kcal. /mole for cerium sesquioxide and ?H°298.15 = -137.16 ± 0.30 kcal./mole for bismuth sesquioxide. The free energy of formation was estimated for cerium sesquioxide and accurately calculated for bismuth sesquioxide. The data were compared with values in the literature.

Jan 1, 1961

Production from a major, deep orebody requires the construction of two 6 m diameter, 1000 m deep ventilation shafts over the next three years. Further ventilation upgrades have foreshadowed an additional 1500 m of 6 m diameter shafts beyond that. After reviewing the construction alternatives it was decided to raisebore the first shaft in one pass using Western Mining Corporation's 121R raiseborer and the Wirth sequential head. The significant cost and speed of construction potential of 6 m raiseboring justified the risks associated with this new technology. Large diameter sequential head raiseboring has only been carried out in South Africa. Over the last three years many lessons have been learnt and the technology has progressed to being considered feasible. Operating practice and the optimisation of raiseboring performance for specific ground conditions are the areas requiring further work. The development of large diameter raiseboring in South Africa and the site preparation and initial operation at Z.C. Mines are described. Comment on actual operating experience includes the geotechnical investigations, the raiseborer foundations, cuttings disposal and the drilling of the pilot hole which has progressed to beyond 450 m. Unforeseen difficulties with the verticality of the pilot hole and with mud losses illustrate the types of problems that can be expected.

Jan 1, 1988

By D. Pennington

Ground-water levels and subsidence have been monitored over a longwall panel of a deep coal mining operation located in western Pennsylvania. The monitoring network includes eleven ground-water monitoring wells completed to measure water level changes in separate shallow and deep aquifer zone-, and 50-foot surveyed subsidence stations parallel and perpendicular to the panel centerline. Monthly monitoring data were collected during the premining, mining, and postmining tine periods. Aquifer testing and borehole geophysical logging were conducted during premining, and post-mining conditions to document any changes in aquifer properties and ground-water flow patterns. Results indicate ground-water declines were located with respect to the mining face and mined longwall panel. Dewatering of the deep aquifer zone caused a significant water level decline in deep wells; however, the shallow aquifer zone was isolated fro major impacts by an aquitardal layer during, the, one-year period. Transmissivity data were greatly impacted by fracturing, in the highly anisotropic aquifer system. Borehole geophysical logging indicated changes in ground-water flow patterns and zones of increased fracturing from subsidence.

Jan 1, 1984

By Robert Lee Stahl

Comprehensive field tests were made by the Bureau of Mines at the Schwartzwalder mine near Golden, Colo., to determine whether surface geophysical techniques could be used to detect and delineate faults in uranium deposits. The tests included seismic refraction, magnetometer, electrical resistivity, airborne infrared thermal scanning, and airborne photography. Of the several geophysical techniques tested in the field, horizontal resistivity profiling with electrode spacings in the range of 10 to 15 feet was most diagnostic of faults. The method is quick, inexpensive, and accurate and can be easily used by mining company personnel to detect and delineate faults.

Jan 1, 1974

By Richard B. Berg

Chlorite veins in the Silver Star district (40 km southeast of Butte) were of little interest to those who were mining gold and silver in the late 19th century. It wasn't until 1975 that unusually pure magnesian chlorite of the variety clinochlore was identified from a ?talc? claim in this district. In 1977 tests by Cyprus Industrial Minerals showed that this chlorite was suitable for use in ceramics. Mining begun in that year continues. These replacement veins of chlorite in Precambrian quartzofeldspathic gneiss differ from the metalliferous veins to the northwest in both attitude and mineralogy.

Jan 1, 1982

By Hale Y. M

Multielement reconnaissance geochemistry coupled with ground scintillation gamma ray measurements has been used to investigate the dispersion patterns of uranium and other major and trace elements in the arid Palmyrides region of central Syria. This region occupies an interplatform depression in the northern part of the Arabia Plate, upon which sediments up to 10 km thick have accumulated. Outcrops of strongly fractured Mesozoic and Cenozoic rocks form two major mountain belts, the northern and southern Palmyrides, between which is located the closed Ad-Daww basin, with a thick Neogene and Quaternary clastic cover. Among the various lithologies, phosphorites are well represented. Uranium and associated elements have been incorporated into the Upper Cretaceous and Lower Palaeogene sediments, especially the phosphorites, which are well represented in the region. These elements are derived from three possible sources, namely, sea water, Lower Cretaceous volcanism and metalliferous fluids leaking along taphrogenic lineaments. In and around the phosphorites, numerous traces of secondary uranium mineralization occur. Over 500 geochemical samples of outcropping rock, wadi and playa sediments, overburden and groundwaters were taken over an area of approximately 9000 sq km. Most samples were analyzed for 25 major and trace elements by nebulization ICPAES; for As, Sb, Bi and Se by hydride generation and ICPAES; and for U, Th and La and other REE by neutron activation analysis.

Jan 1, 1988

By Natalie White, Joel Asp, Allyz Kramer

"Minnesota has robust reclamation standards and have proven results in the taconite mining industry. Reclamation of overburden spoils, lean ore spoils and fine tailings from taconite production has generally been successful on the Iron Range, using a low input standard reclamation practice. Success at reestablishing vegetation on these landscapes is likely due to fairly favorable chemical and physical properties (e.g., few limitations due to acidic generating materials, metal toxicities and water and nutrient holding capacities). However, coarse tailings reclamation has proven more difficult, presumably due to lower nutrients and challenges with moisture holding capacities. Research efforts conducted since 1990 have struggled to develop a reclamation strategy for coarse tailings that meets the Minnesota Mineland Reclamation Rules, Chapter 6130. However, new breakthroughs in scram mining technologies are producing fine and coarse tailings that have not been encountered nor reclaimed in northern Minnesota. Scram mining in Minnesota is defined as those mining operations that produce natural iron ore concentrates. Innovative research is underway to investigate and determine successful reclamation strategies to reclaim scram mining tailings from these scram mining operations. The research program is conducted through collaboration with SEH, Prairie Restorations, Inc. (PRI) and Mining Resources, LLC with funding support from the Iron Range Resources and Rehabilitation Laurentian Vision Partnership minescapes grant program.The research program was divided into three phases:Phase I. Bench-scale testing to identify successful treatments to reclaim and restore scram tailings through evaluating surface soils amendments, viable seed mixes and plant germination, growth and densities. Phase I was completed in early 2015.Phase II. Field-scale pilot trial to test larger scale effectiveness of the treatments deemed successful in Phase I and test various vegetative assemblages and planting techniques focused on the unique challenges with scram tailing basins. Phase II was completed in late 2016 with a summary monitoring report.Phase III. Produce a technical report of results for the research undertaken in this study, as well as compile prior reclamation results used during previous Minnesota iron mining reclamation projects on tailings basin applications. Phase III was completed in 2017 with a summary monitoring report and recommendations."

Jan 2, 2018

By William E. Hughes, Roderick K. Davey

The objective of this chapter is to review and discuss interpolation techniques commonly in use in the mining Industry today, including simple examples. This chapter will not attempt to compare the relative accuracy of each technique as this subject has adequately been covered by several authors (Knudsen and Kim, 1967; David, 1974; and Barnes, 1979) When appropriate, methods will be compared relative to the results of simple examples and computational ease. The examples presented are based on metallic deposits. The techniques, however, are not restricted to metallic deposits and can generally be applied to nonmetallic ones. The purpose of interpolation, as applied to a mineralized deposit, 1s to extend the knowledge of the grade and geology of localized samples to an estimate of the grade and mineralogy of a larger block of ground or even an entire deposit. The word interpolation means to compute values between given values and is limited to that region between the known values. The distinction between interpolation and extrapolation is important and must be adhered to in the application of these techniques in general, the interpolation must be limited to the area enclosed by verified samples. The methods being discussed can be broadly broken into three categories. ( 1 ) geometrical methods, (2) distance weighting methods, and (3) geostatistical techniques.

Jan 1, 1979

By R. Hamilton

"Louvicourt mine began operation in 1994. It is located in northwestern Quebec, 20 km east of Val d’Or. The mine is owned by Aur Resources (30%), which operates the mine, Teck/Cominco (25%) and Novicourt (45%). By the end of 2002 there were approximately 280 employees working on the site, including contractors. Production averages 4300 tons per day, working a massive sulphide body located between 415 m and 920 m underground.Maintenance expenses represent 27% to 29% of the operating costs, and the maintenance personnel represents 34% of the total workforce (including electrical, mechanical and concentrator maintenance staff). Considering these figures, in addition to capital costs and indirect costs, such as energy (electricity, fuel, gas, etc.), it is worthwhile to pay attention to how things are done in order to protect such investment. Every task performed to help understand the impact of Louvicourt’s practices must to be seen as an investment in the reliability of its operation."

Jan 1, 2003

By Paola Lazari de Aguiar

A indústria automobilística, principalmente, tem exigido o desenvolvimento de novos materiais que permitam a redução do peso dos veículos devido ao impacto do peso no consumo de combustíveis e emissão de poluentes. Assim, novos estudos têm sido realizados visando a redução da densidade dos aços através de adições consideráveis de alumínio. Neste contexto, este trabalho discute e revê a possibilidade de projetar aços contendo teores consideráveis de alumínio, e outros elementos de liga como Mn e C, através da termodinâmica computacional e bancos de dados comerciais. Como verificação preliminar, foram avaliados, experimentalmente, alguns equilíbrios e medidas de frações de fases em um aço experimental e os resultados obtidos foram comparados com os valores calculados e informações da literatura. Os resultados indicam que, para uma ampla faixa de composições os bancos de dados comerciais disponíveis parecem adequados ao projeto destas ligas.

Oct 30, 2017

By R. J. R. Welwood, F. J. Grebenc

"Brunswick Mining and Smelting Corporation Ltd. (controlled by Noranda Mines Limited) operates two lead-zinccopper- silver mines approximately 20 miles inland from Bathurst, N.B. The principal No. 12 orebody is mined by underground methods; the second, the No. 6 orebody (6 miles away), is recovered by open-pit mining. No. 12 underground operations ar•e in two parallel massive sulphide orebodies about 400 ft apart, dipping at 75 to 80 degrees and plunging almost vertically. The initial mining phase involved longhole open stoping from the 1550 level to the crown pillar, with main levels at 150-ft intervals and sub-levels between at 75 ft. Stope dimensions average 120 ft long, 100 ft wide and 400 ft high, with alternate rib pillars as well as sill and crown pillars. Initially, ore was transferred through scram drifts below each stope by means of 125-hp electric slushers and 72-in. folding scrapers, being delivered to gravity ore-pass collection •systems feeding a primary jaw crusher below. Later, track and trackless drawpoints were utilized below most longhole open stopes and pillars. Rib pillars were recovered by longhole methods, with large blasts into a central slot and undercut, after adjacent stopes had been filled. Waste-rock stripping from No. 6 open pit has been supplied to No. 12 stopes as backfill, by means of gravityfill raises.In 1968, the decision was made to mine the remaining ore zones by mechanized cut-and-fill methods, utilizing Load-Haul-Dump equipment. Currently, approximately 60 per cent of No. 12 mine production comes from mechanized cut-and-fill mining. As before, backfill is supplied from No. 6 open pit stripping waste rock, which has been crushed to minus 6 in. The ultimate objective is to supply virtually all production requirements by mechanized cut-and-fill techniques. The No. 6 open pit, which commenced production in 1966, covers an area of 1,500 by 1,200 ft, equivalent to 41 acres approximately. Ramp roads are graded at 8.5 per cent. Each mining bench is 36 ft high and the ultimate pit will consist of 14 benches for a final pit depth of 504 ft. Present depth is 180 ft."

Jan 1, 1971

The Bureau of Mines is operated to assist in promoting economic development through increased efficiency in the mining, preparation, treatment, and utilization of mineral substances; to aid in conserving mineral resources through preventing waste; and to help the mining industry improve health conditions and increase safety. Accomplishment of those ends is sought through investigation of scientific, technologic, and economic problems of the, mineral industries and dissemination of resulting information. Building materials of mineral origin constitute an important product of mining, and the Bureau makes studies of these in the various fields mentioned. The following commodities come within this classification: Asbestos, anhydrite, asphalt, cement, clay and clay products, diatomite, dolomite, glass and mineral wool, granite, greenstone, gypsum, lightweight building materials, lime, limestone, magnesite, marble, sand, sand and gravel, sandstone, sand-lime brick, slate, soapstone, and trap rock.

Jan 1, 1937

By Mariana Beatriz dos Reis Silva

A influência do tempo entre passes na evolução microestrutural de dois aços austeníticos, F138 (sem nióbio) e ISO 5832-9 (com nióbio), foi investigada através ensaios de torção a quente em condições industriais. Análises foram realizadas através de microscopia ótica e eletrônica de transmissão, EBSD e microdureza. Menores tempos entre passes produziram menores tamanhos de grãos e de precipitados. Microestruturas mais refinadas induziram a maiores microdurezas. O aço ISO 5832-9 apresentou maior resistência que o F138. Precipitações de TiNbN, após o encharque, e de NbCrN e NbN (5%), durante o processamento, foram observadas no aço ISO 5832-9. Ambos os materiais sofrem recristalização dinâmica, partículas grosseiras (> 200 nm) atuaram como partículas de reforço e partículas menores (< 50 nm) no ancoramento dos contornos de grãos e discordâncias no ISO.

Jan 16, 2018