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By A. R. Chambers

At the 1924 Annual Meeting of the Institute, held in Toronto, the writer presented some notes on the occurrence of salt at Malagash, Nova Scotia, together with a few remarks on the uses of salt. The development of these salt mines has attracted considerable attention to the district, and it may be of interest at this time to call attention to some of the newer uses of salt, and to give a brief account of the genesis of the Maritime salines, As it is not proposed to treat the subject in technical detail, and the paper is written in a lighter vein than is usual in contributions to your Transactions, you will please overlook any variations from a strictly technical method of presentation. The world's supply of salt is obtained in three principal ways: (1) By flooding shallow areas, or pans, with sea water, allowing the water to evaporate naturally by the heat of the sun's rays, and collecting the residue of solid salt. This method is employed, for example, at Turks Island, B.W.I. (2) By mining the rock salt in its natural state, and preparing it for market by a grinding process. This is the method adopted at Malagash, which is the only place in Canada where salt is actually mined. (3) By drilling a hole into an underground salt deposit, forcing fresh water clown the hole, and, after it has become saturated with salt, pumping the brine to the surface and recovering the salt by evaporation. This is the method pursued by the Canadian Salt Company, the Dominion Salt Company, and other producers in Ontario.

Jan 1, 1929

By Francois Mignard

With a limited global steel production growth, automotive application market shows interesting volumes and trends especially in emerging countries. The recent period has again enabled Siemens VAI to confirm a position amongst leading suppliers of new plants serving high-end steel production in particular for unexposed and exposed automotive material. With a series of recent plant references in operation and under construction, relevant answers to such sustained level of performances are highlighted along the downstream processes. Designed for a wide range of applications, Siemens VAI processing lines includes advanced technological and state-of–the art equipment, among them, Solid state laser welder, Pickling Tunnel tanks, Skin pass mill and Tension leveller, Side trimmer with dynamic width adjustment, and new generation of Automatic surface inspection systems. With a continuous aim of driving improvements, Siemens VAI has also developed Global Quality Monitoring solutions notably through advanced software which provide just-in-time warnings and assist steel makers in the daily operation of their lines. As lifecycle partner, Siemens VAI offers solutions and services in metallurgical expertise from metallurgical modelling, through physical simulation on rolling, annealing and galvanizing processes, and enables Siemens to accompany our customers along with their project definition till fulfilment of highest market requirements.

Jul 30, 2018

By N. Kuroda

A realistic simulation model has been used for designing longwall mining, especially for solving operational problems. This paper describes background, development, validation and some applications of the simulation model for mining people who are unfamiliar with O.R. or computer technique, as a simple planning tool. The following items were established: logical analysis and algorithmic design for practical longwall mining, structure of hypothesis behavioral organism, input parameters, using practical knowledge and operational statistics of the mechanized longwall system experienced for many years.

Jan 1, 1982

By John O. Atkins

[Experiments were conducted by the Bureau of Mines on five types of simuated lunar rock (dacite, tholeiitic basalt, vesicular basalt, pumice, and uluth Gabbro) to study the effects of various simulated lunar environments n their strength and deformational properties. Specimens were tested in an ltrahigh vacuum (UHV) system at pressures ranging from atmospheric down to 0-11 torr and at temperatures of -130°, 20°, and 135° C. All tests were onducted with a servocontrolled testing machine. Rock specimens tested at 0° C in UHV exhibited significantly higher compressive strength and Young's odulus than those tested at 20° C in atmospheric pressure. The magnitudes f increase are related to the porosities and permeabilities of the rock pecimens; high porosity and permeability allow better outgassing and thus nprove surface cleanliness in UHV. The compressive strength generally ncreases but Young's modulus decreases as test environments change from 20° C i UHV to 135° C in UHV. No significant difference was observed in the iysical properties measured at 20° C in LTV and -130° C in UHV. Anisotropy i strength and Young's modulus exist both in UHV and at atmospheric condi¬'.ons with the same symmetry pattern. The orientations of the principal axes iy, however, change from the atmospheric to UHV condition. The results idicate that rock fragmentation in lunar environment will require more ergy than that at 20° C in atomospheric pressure.]

Jan 1, 1974

By D. Harrington

Every few weeks United States newspapers of 25 or 30 years age ran scare-heads telling of some mine disaster, which was a first-page attraction for a day or two and then was forgotton until another disaster occurred a few weeks later. Interspersed with these disasters were the so-called sniping mine accidents, causing the death of one or two mine workers. The summation of all types of mine fatalities usually exceeded 3,000 a year. In the period 1906-10, inclusive, there wore 84 major explosion disasters (or about 17 per year) in united States coal mines; the fatalities resulting from those disasters numbered 2,388 for the 5-year period. These frightful catastrophies helped to cause the total number of fatalities in our coal mines for the 5 years (including the fatalities from major explosions) to reach the enormous total of 13,288, an average of 2,658 per year. In addition, some hundreds of other typos of mining accidents swelled the annual fatality list to upwards of 3,000. This admittedly deplorable condition created so much Nation-wide comment that Congress was impressed with the necessity of having something done by the Federal Government with a view to trying to halt at least sonic of the excessive loss of life in our mines; in consequence, the Bureau of Mines was created and began to function in July 1910.

Jan 1, 1935

By N. F. Faria, F. Monteiro, B. O. Taiwo, A. Palangio, D. Fonseca, J. Manuel

This paper explores the interpretation and application of Particle Size Distribution (PSD) curves in optimizing blast design and enhancing downstream operations. The study looks at important factors like D50, D80, fines content, and the uniformity index to show how PSD curves affect the efficiency of different mining processes. The first section of this paper discusses the impact of blast design parameters such as burden, spacing, and explosive energy on the resulting PSD, highlighting their significance for downstream operations like crushing, and material handling. The section concluded that proper alignment of PSD with downstream size classes, like primary crusher inlet sizes, among others, can result in substantial cost reductions and productivity gains. The second part presents a case study from dstgroup aggregate quarry in northern Portugal, utilizing fragmentation analysis to evaluate blast performance and promote continuous improvement. The section specifically examines the effect of stemming material size on blast fragmentation, comparing the impact of using aggregate with a D80 of 12.32 mm versus a D80 of 21.94 mm. The D80 value represents the particle size at which 80% of the stemming material is smaller, making it a critical parameter in evaluating the stemming's effectiveness in confining explosive energy. The drilling and blasting designs were meticulously planned using O-PitDev and O-PitSurface software to ensure accuracy in blast parameters and layout. To assess the fragmentation resulting from these different stemming material sizes, the study utilized WipFrag 4 software. The software allowed for precise measurement of particle size distribution after the blast, as well as a detailed comparison between the two stemming sizes. Results from the analysis indicate that using bigger-sized stemming material led to improved blast confinement, which in turn resulted in better fragmentation compared to the smaller-sized material. The reviewed blast videos demonstrate that the larger aggregate effectively contained the explosive energy within the borehole, thereby reducing premature venting and directing more energy towards breaking the surrounding rock mass. This led to finer fragmentation with D80 = 1240.1 mm, D50 = 685.9, and Dmax = 2580 mm, which is advantageous in downstream operations like crushing and milling. On the other hand, the smaller stemming material (D80 = 21.94 mm) did not confine the explosive energy as efficiently, resulting in coarser fragmentation (D80 = 1327.37 mm, D50 = 750.76, and Dmax = 2370 mm) and reduced overall blast efficiency. These findings highlight the significant influence of stemming material size on blast performance and fragmentation outcomes. 

May 4, 2025

By Susan G. Bilhorn

A number of studies have been conducted in active and inactive mine environments using continuous monitoring and data acquisition systems to detect various parameters. In addition to the information obtained for research purposes, these monitoring systems can provide a means to remotely collect required information (such as radon daughter concentrations and air velocity) and control various conditions (such as fan operation and air door position) in numerous working sections of an active mine. Selection of detector locations and placement, which are critical to obtain the information and control desired while not inhibiting mine operations and influencing the detector readings, are covered in this paper.

Jan 1, 1984

Jan 1, 1942

By d&apos, D. V. Andrea

Nine rock properties were determined for rocks coming from 49 locations and having a wide range of compressive strengths. Plots of the nine rock properties versus each other were prepared. A stepwise multiple linear regression analysis was performed to obtain several equations for predicting compressive strength. Both linear and curvilinear relationships were assumed between compressive strength and the other rock properties. The prediction equations had multiple correlation coefficients ranging from 0.947 for an equation with 1 variable (point load tensile strength) to 0.986 for an equation with 25 variables. Of the properties tested only point load tensile strength could be used alone to estimate compressive strength with fair accuracy.

Jan 1, 1965

By William E. Lamont

The Mineral Resources Institute (MRI) of the School of Mines and Energy Development (SOMED), University of Alabama conducted studies to determine the potential for upgrading the Eastern Devonian shales by flotation. Results of those studies indicate that flotation concentrates containing 150 liters of oil/t (36 gal/t) can be produced from shale containing 50 liters of oil/t (12 gal/t) as determined by Fischer Assay with good recovery of the kerogen. Organic carbon and trace elements such as molybdenum, vanadium and uranium also are concentrated with the kerogen. Kerogen concentration was found to be a function of the size of grind.

Jan 1, 1983

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

Jan 1, 1942

By D. Van Orden, Y. Kamiya, R. Lee, E. Ilgren

Crocidolite is a well-known causative agent for mesothelioma. However, studies have shown that the pathogenicity of the fiber from different mines varies considerably and it has been postulated the parameter that appears most likely to account for this variation is fiber width although this has never been formally confirmed. To date, crocidolite appears to be the only asbestos mineral for which an epidemiological study comparing the risk of mesothelioma in a population exposed to ‘thin’ fibers with another exposed to ‘thick’ fibers of the same species may be carried out. Finnish anthophyllite, South African amosite, and African Transvaal crocidolite can also be classified as thick fibers, and there is a paucity of mesotheliomas in populations exposed to them compared to those exposed to thin Cape crocidolite. No thin occurrences of these minerals are known. Our previous study looked at crocidolite from several sources. The present study considers the amphibole anthophyllite found in many places in the world. This mineral, regardless of source, does not show the same variation in fiber width found with crocidolite from different areas. All anthophyllite fibers that have been mined may be classified as thick and populations exposed show very low levels of mesothelioma. We suggest the most likely explanation is related to the fiber width distribution and a concomitant reduction in the ‘Stanton fiber size’ fraction.

Jan 1, 2012

By David B. Reger

New discoveries of gas in the southern counties featured the petroleum industry in West Virginia during 194;. Drilling for oil increased slightly over 1944 and a small increase of initial production resulted. Out of 28 wildcats drilled, there were 16 gas discoveries and 12 dry holes. No commercial oil was found in the 28 wells.

Jan 1, 1946

By J. A. Mielczarski

An infrared external reflection spectroscopy (ERS) technique has been developed to study the structure of the adsorbed layer of ethyl xanthate formed on copper and natural chalcocite (Cu2S) electrodes. The infrared technique provides information concerning the identity and the orientation of the adsorbed species at monolayer and submonolayer coverages. X-ray photoelectron spectroscopy (XPS) studies have also been conducted to monitor changes at the surface. The results show that the first oxidation peak on the voltammograms for copper and the first and second oxidation peaks on the voltammograms for chalcocite electrodes are not characteristic of a chemisorbed xanthate species, which is contrary to what has been reported by other investigators previously. As evidenced by the XPS spectra, there was an increase in sulfur relative to copper on the copper and chalcocite surfaces over the potential region where these oxidation processes occur. The spectroscopic results (ERS, XPS) indicate that the second and third (on copper) and the third and fourth (on chalcocite) oxidation processes recorded on the voltammograms are due to cuprous ethyl xanthate adsorption. The orientation of the adsorbed molecules of xanthate was observed to change with increasing surface coverage. Therefore, it has been concluded that xanthate can modify the copper and chalcocite surface in two different ways. At lower potentials, xanthate is a source of sulfur for the formation of a sulfur-rich surface. At higher potentials, an adsorption layer of cuprous ethyl xanthate is formed. Contact angle measurements show that both of these processes of xanthate surface modification lead to an increase in the hydrophobicity of the substrates.

Jan 1, 1990

"10.1. IntroductionAs discussed by Westland (1981), the six platinum-group elements (PGE) belong to the Group VIII transition metals, to which iron, nickel and cobalt also belong. The chemical similarity between these nine metals accounts for the fact that they tend to be concentrated together as a result of geological processes. These processes started to effect the distribution of these metals at the very beginning of the earth's history.The first line in Table 1 gives the concentration of nickel and certain other Group VIII transition metals in carbonaceous chondrites, those meteorites with a composition that is believed to reflect best the composition of our planetary system apart from hydrogen and helium. The second line is the estimated concentration of the same elements in the earth as a whole. It is seen that these two estimates are quite similar, the earth being perhaps 2 to 3 times richer in these particular metals than the planetary system as a whole. The reason for this is not fully understood, but it may be due to the earth being formed by the accumulation and capture of a greater proportion of iron (and therefore siderophile-rich) than stoney (and therefore siderophile-poor) planetesimals than the planetary system itself.The third line in Table 1 is the average composition of the crust of the earth. With the exception of iron, all of the Group VIII transition elements are rare in the crust, present at concentrations of It tOO to Itt ,000 of that of the bulk earth. This is because the outstanding chemical characteristic of this group of elements is their siderophile nature; that is, their tendency to alloy with metallic iron. Because of this, once the earth became molten very early in its life history, these elements dissolved in the molten iron present at this stage and were removed from the outer accessible parts as this dense liquid sank to the centre of the earth to form the core. Although iron was the main instrument of concentration of the Group VIII metals, its much greater over-all abundance and its ability to combine with oxygen more easily than the others in the group means that significant amounts still remain in the oxidized portions of the earth.The fact that most of the Group VIII metals are available to use in workable concentrations at all is that they are 5 to 30 times more concentrated in the earth's mantle than the crust, as shown in line 4 of Table I. There has been a constant, if slow, interchange of matter between the mantle and the overlying crust throughout most of the earth's history and, under certain circumstances, this interchange has given rise to economic concentrations of metals."

Jan 1, 1979

By E. L. Garton

The Bureau of Mines for a number of years has been conducting an investigation of crude petroleum from producing fields in the United States and the Western Hemisphere and has published a series of reports on these fields. Analyses of crude-oil samples from many oil fields of Oklahoma are given in Bulletin 2913. Analyses of 21 representative crude oils from various producing zones of the Oklahoma City field are given in this report. A close study of the analyses reveals very few differences in the general characteristics and chemical properties of these oils.

Jan 1, 1932

By A. D. Garman

This paper presents one of a series of digests of foreign mining legislation and court decisions which is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate mines in various foreign countries . This interpretation of the laws of El Salvador has been prepared from the best available information in Washington , but is released subject to correction and amplification , if necessary , by the proper American diplomatic and consular officers to whom it is being referred through the courtesy of the Department of State . Under the terms of the Code of Commerce ( arts . 12ff . ) , foreigners living in El Salvador can engage in business on the same terms as nationals . This involves ( = $434.00 ) - except for those with a working capital , of less than a thousand pesos inscription in the merchants ' register , which can be refused only in case of manifest disability of a permanent nature .

Sep 1, 1930

By Caroline Gomes de Oliveira

A busca por materiais que atendam as demandas ambientais que vem surgindo com o passar dos anos abre um importante mercado para a aplicação de fibras naturais. Além de biodegradáveis e provenientes de fontes renováveis, as fibras naturais possibilitam a produção de materiais compósitos de baixa densidade e com boas propriedades mecânicas. Para aumentar ainda mais essas propriedades, estuda-se o uso de tecidos de fibra natural em vez das fibras alinhas. As principais vantagens desta nova configuração são o reforço em mais de uma direção ao mesmo tempo e o fato de serem mais compactos, viabilizando a incorporação de uma fração maior de material de reforço. O presente trabalho investigou a resistência ao impacto de compósitos de matriz poliéster reforçados com tecido puro de rami, que é uma das fibras lignocellusosicas mais resistentes encontradas até hoje. Os corpos de prova foram reforçados com 1, 2 e 3 camadas de tecido e foram ensaiados num pêndulo de impacto Izod. Concluiu-se com base nos resultados que o aumento da fração volumétrica de tecido aumenta a resistência ao impacto dos compósitos.

Aug 17, 2017

By Jorge Rodríguez V

El presente trabajo plantea una alternativa al sector cuprífero en tanto ofrece tecnologías que representen un valor agregado de los productos que se obtienen y un valor de uso intensivo Para logar este resultado, la recuperación del cobre se realizaba a través de la vía hidrometalúrgica, donde se empleaba la reducción por contacto con chatarra de fierro. Sin embargo, los trabajos actuales utilizan los solventes para la producción de sales de sulfato de cobre, logrando operaciones de selectividad de iones y concentración de los mismos. En consecuencia, el texto es describir los principales aspectos de investigación (batch y contínuas) para la producción de oxisales de cobre a través de soluciones cosechas de lixiviación de minerales oxidados de cobre.

Aug 26, 1988