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By G. L. Smit

The Buffelsfontein Gold Mining Company is situated in the Klerks-dorp district of the Province of the Transvaal in the Republic of South Africa, approximately 100 miles west of Johannesburg. Gold production commenced in January 1957 and Uranium treatment of residue slimes as a by-product started in July 1957. The mining property is 5435 mining claims in extent, the equivalent of 7,988 acres or 12.5 square miles. The mine was initially exploited by the Pioneer Twin Shaft System, consisting of a 26 feet diameter down-cast shaft and a 22 feet diameter up-cast shaft, sunk in the north-west area of the mine to cater for the hoisting and ventilation requirements for a milling rate of 150,000 tons per month.

Jan 1, 1964

By Alessandra Savazzini dos Reis

A crescente preocupação em relação às áreas de proteção ambiental e ao alto consumo de argila, matéria-prima da cerâmica vermelha, ocasiona a indisponibilização progressiva de reservas de argilas no Brasil. Com isso, vê-se a necessidade de incorporar resíduos na massa argilosa para confecção de produtos de cerâmica vermelha. A indústria de cerâmica vermelha brasileira consome cerca de 10 milhões de toneladas de argila ao mês para produção de telhas e blocos. Na própria olaria são gerados resíduos, tal como, o resíduo de massa cerâmica crua originado na etapa de conformação das peças. Este trabalho visa incorporar o resíduo de massa cerâmica crua na massa argilosa usada em cerâmica vermelha. O resíduo foi caracterizado por meio de ensaios de FRX, DRX, limites de Atterberg e distribuição de tamanho de partículas. Corpos de prova feitos com massa argilosa e resíduo em teores variando de 10% a 90% (massa) foram conformados, secos à 110ºC, queimados à 900ºC em forno industrial e submetidos a ensaios de absorção de água, porosidade aparente, massa específica aparente e resistência à compressão. Os resultados evidenciaram que as propriedades cerâmicas avaliadas nos corpos de prova da massa argilosa incorporada com o resíduo atendem aos valores das argilas-padrão brasileiras para cerâmica vermelha.

Aug 17, 2017

By Arno C. Fieldner, Howard I. Smith, J. W. Paul, SAMUEL SANFORD.

Many mine samples of coal are analyzed each year in the laboratories of the Bureau of Mines. The analyses are made in connection with investigations relating to fuels belonging to or for the use of the United States Government, the causes of accidents in coal mines, the geologic relations of coal beds, and the character and the value of the coal and lignite in the public lands. The systematic collection and analysis of such samples in connection with fuel investigations was begun in 1904 at the Government fuel-testing plant at the Louisiana Purchase Exposition, and was under the direction of the United States Geological Survey for six years. Descriptions of the coal samples collected between the beginning of this work, July 1,1904, and the transfer of the fuel-testing and mine-accident investigations to the Bureau of Mines, July 1, 1910, were compiled and published in Bureau of Mines Bulletin 22.a Descriptions and analyses of samples collected during the fiscal years 1911 to 1913 were published in Bureau of Mines Bulletin 85.b The present bulletin presents analyses and descriptions of samples collected during the fiscal years 1913 to 1916. In order that the material in this bulletin may be used to supplement that presented in Bulletins 22 and 85, the same plan of geographical classification has been followed, the analyses and descriptions of the samples being grouped in alphabetical order according to the State, county, and town near which the mines or prospects sampled are situated.

Jan 1, 1918

By W. S. Fyfe, G. V. Albino, Ekawat Sitthithaworn

The mineralisation is associated with a composite diorite to quartz monzonite stock of Permian to Triassic age that intrudes Devonian carbonate strata. In the intrusive rocks it is associated with potassic alteration and in the carbonate wall rocks it is hosted by prograde garnet-rich and retrograde epidote-rich skarn. Both porphyry and skarn mineralisation include disseminated and fracture-controlled mineralisation, the latter probably accounting for the major part of the contained minerals. Copper, gold, silver and zinc are strongly positively correlated within the mineralised zones, although there are small differences in metal ratios between the different ore types; molybdenum appears to be negatively correlated with copper and gold. Ore minerals include chalcopyrite, magnetite and pyrite in porphyry-type mineralisation and bornite, chalcopyrite, pyrite, magnetite and lesser haematite in skarn.

Jan 12, 1993

By Sam S. Taylor

[The discovery of many oil fields in Illinois since 1936, and their rapid development have brought the problem of brine disposal to the foreground in that State. The ultimate magnitude of the problem is not yet known, but already it is treat enough to warrant technical investigation. The Bureau of Mines, therefore, has made a general survey of the methods of handling oil-field b brines in Illinois rend has studied in detail three subsurface disposal systems.]

Jan 1, 1940

By NEWTON B. KNOX

IN Bolivia, mining is still the principal economic activity, as it was before and during the Spanish Colonial period. Tin, tungsten, antimony, copper, lead, zinc, gold, silver, sulphur, and a little bismuth are produced. The Andes mountains are divided into two main ranges in Bolivia; the Western range marks the border with Chile and the Eastern range forms the backbone of the country; in the North it drops rather abruptly eastward, to the plains of the Beni, whereas in the South it splits and is separated from the Chaco flatlands by a series of folded mountain ranges. In general the mineral deposits are found within the Eastern range or in the hills that rise from the high plateau between the ranges - really parts of the Eastern range partly submerged by recent sediments. The mineral belt is thus over 500 miles long and about 100 miles wide and includes most of the principal centers of population and the most important means of communication. The region is mountainous and the roads are bad; furthermore labor is a serious problem, for the land is poor and the agricultural population is never far from hunger. The floating supply of miners is limited and soon exhausted in any emergency like the present.

Jan 1, 1945

By Orica

Unlicking the Possibilities ISEE Digital Detonator Workshop New Orleans, LA Wednesday, February 4, 2004

Jan 1, 2004

By W. D. Macleod

This paper describes a mineral dressing process for the upgrading of tin ores. The process described is called 'agglomeration' and. is similar in many respects to flotation. Many variables have been examined experimentally both on batch and continuous operations and are reported upon herein... Using a Mt. Pleasant tin ore, assaying 0.5% Sn, an upgrading to 8% Sn, with a recovery of 95% could be obtained by this process.

Jan 1, 1966

By B. I. Ferber

Toxic and explosive atmospheres are discussed, along with some of the instruments commercially available for their detection. No attempt has been made to evaluate the accuracy of anyone device. This circular has been prepared primarily to aid mine inspectors in selecting suitable instruments for underground gas detection.

Jan 1, 1972

By Greg Beckstrom

On Oct. 1-3, SME?s Twin Cities chapter (SME TC), in cooperation with the University of Minnesota ? Duluth?s Precambrian Research Center (UMD-PRC), cohosted a symposium on silica sand mining and processing. The conference was held at the Earle Brown Heritage Center near Minneapolis. The symposium was followed by a day-long field trip to operating mines, processing plants and loading facilities located in southwestern Wisconsin. Speakers and attendees at the symposium included university professors, industry experts, regulators, mining company representatives, equipment suppliers, consulting engineers and service companies. Approximately 320 people attended the conference. In addition, about 50 people who oppose mine development and the oil and gas industry showed up to voice their displeasure with the event and those companies that operate in this space.

Jan 1, 2012

By Carl Fisher

A microseismic roof fall warning system was field tested in Western and Eastern coal mines in the United States to better define the capabilities and limitations of the microseismic method in predicting roof fall Microseismic event and energy type data were obtained and documented for twenty-three coal mine roof falls. Field test results indicate that both the microseismic event and energy methods, as applied in this development effort, have a high probability for successful application in a commercially practical roof fall warning system. Based on the results and experience obtained during field testing, a commercial prototype microseismic roof fall warning system was designed and constructed. Although it was the intent of the program to field test the commercial prototype system, delays in equipment fabrication and contract time limitations did not permit field testing.

Jan 1, 1980

By T. C. Craig

For the year 1934, there were 382 oi1 wells completed for a total initial of 146,965 bbl. Fifty-three wells were deepened for a total increase of 8363 bbl., bringing the total volume of new oil to 155,328 bbl. As of Jan. 1, 1934, the daily potential of the field as determined by the Texas Railroad Commission was 159,740 bbl. Of this amount 26,429 bbl. is "marginal oil," and 2682 bbl. is exempt on account of water. In December, 1934, the daily potential was established by the Railroad Commission as being 297,501 bbl. with a daily allowable of 56,800 bbl. Of this amount 31,993 bbl. is "marginal oil," and 2183 bbl. is exempt on account of water. There has been no field-wide test made during the year, and as a result the rated potential of the field is in all probability much higher than the actual potential. As each new well comes in, a five-day test is made under the supervision of the Railroad Commission. The potential thus established is added to the field potential and shares its pro rata part of the market outlet, which is the allowable production, no allowance

Jan 1, 1935

By Tomek Ulatowski

INTRODUCTION In 1974, Industrial Miners Mexico, S.A. (IMMSA), agent for the borrowers, was the largest privately-held mining, smelting, and refining company in Mexico (accounting for 32% of Mexico's nonferrous metal and coal production in 1974), the fourth largest company in terms of sales, and the second most profitable company in Mexico, excluding government wholly-owned and operated industries. The company was engaged in the mining, smelting and refining of coal, copper, fluorite, gold, lead, silver, zinc and related by-products for domestic consumption and export. A combination of favorable factors led IMMSA to propose an investment plan amounting to US$286 million for 1974 through 1978, of which US$150 million was to be financed. These factors included: Substantial profits in 1973 and 1974 Positive near-term outlook for metal prices Success of the reinvestment program in increasing productivity Substantial additions to proved reserves during 1973-1974 and Fiscal incentives provided by the Mexican government to stimulate investment in the mining industry. The primary purpose of the investment program was to construct a new electrolytic zinc refinery and to expand and modernize many of the company's existing mining and refining facilities. THE BORROWER Company History Compania Miners Mexico, S.A. was incorporated in the city of Monterrey in 1918 as a wholly-owned subsidery of ASARCO Inc. (formerly American Smelting and Refining Company, New York) for the purpose of mining and processing non-ferrous metals and related products. In compliance with the Government's Mexicanization program, ASARCO Inc. divested itself of 51% of its equity in Compania Miners Asarco, S.A. on June 30, 1965. Subsequently, ownership in the divested share was apportioned as follows: 15% ownership in Compania Miners Asarco, S.A. to a group of private investors, and 36% in trust for subsequent public sale. The company's name was changed to Asarco Mexicana, S.A. in 1965. Mexican ownership in Asarco Mexicans, S.A. was increased to 51% in 1967, following the purchase of the 36% share ownership held in trust, and then to 66% in 1974 when ASARCO Inc. divested itself of an additional 15% of its holdings in Asarco Mexicans, S.A. Following its 1974 divestiture of 15% of Asarco Mexicans, S.A., ASARCO Inc's ownership in Asarco Mexicana, S.A. was reduced to 34%. In 1974, the company changed its name for the second time to Industrial Miners Mexico, S.A. (IMMSA). Fiscal Agreement IMMSA entered into a fiscal agreement with the Mexican government in 1969. The agreement, which was renewed in 1974, provided for 100% of the production and export tax corresponding to the federal government with a minimum of 50% of the amount refunded to be reinvested in fixed assets. Further, the agreement permitted the company to

Jan 1, 1985

I have headed this paper with a question and for the impatient among you ûthe answer is no we have not run out of developments but, and it is a big æbutÆ, we need to be innovative and ahead of the game or ænoÆ will be æyesÆ before we know it.Why do I believe that our future lies in innovation? Thirty years ago, knowledge doubled every 14 years. It is now doubling every seven years. In 1965, Gordon Moore, one of the founders of the chip maker Intel, made an observation that growth in memory chip performance is doubled every 18 months which became known as MooreÆs Law. Now there is fibre law, where the transmission line capacity doubles every nine months and storage capacity, under disc law, doubles every 12 months. What does this mean? Well, firstly there is a massive rise in information flow and availability with no limits in growth for at least the next ten years. Secondly, unlike our grandfathers, we are most unlikely to be employed by the same firm for our working career - we may not even have the choice to stay with the same company. In a phenomenon Richard Foster and Sarah Kaplan (2001), borrowing from Schumpeter, termed æcreative destructionÆ, companies are unable to sustain market-beating levels of performance for more than ten to 15 years. In the 1920s the turnover rate of companies in the United States was 1.5 per cent, so a company could employ almost three generations from the one family. A company had a half life of 60 years. In other words, you could well be in the same working environment as your grandparents. Today the churn rate is estimated to be eight to ten per cent. A company has a half life of five to six years. So for large companies, as an employer or employee or as a contractor, your working environment has a 50 per cent chance of changing in five years. Innovation is the driver of this rapid rate of change. Innovation is not for the faint hearted (Cutler, 2001) but it is the core for success in the global economy. The rate of change in our world is not going to decrease. We must learn, not only to manage change, but to enjoy the process of changing û to ride the tsunami of the knowledge economy.

Jan 1, 2002

By J. R. Patts, J. P. Rider, J. A. Organiscak, A. B. Cecala

"NIOSH recently completed a 15-month study at an underground limestone mine crusher booth which evaluated three research parameters: (1) the effectiveness of a single-filter filtration and pressurization system for improving the air quality inside the operator booth, (2) comparing the effectiveness of ? > 99 and ? > 95 experimental prototype filters in the system, and (3) evaluating the use of three different pressure monitoring devices to determine the performance of the filtration and pressurization system over time. The protection factor was quantified monthly using particle counters in the respirable dust range (0.3–10 µm), and gravimetric dust samples were gathered at the beginning and end of the overall study. Under static conditions and after outlier removal, the single-filter filtration unit installed offered a protection factor between 8 and 216, depending on the filter type and loading condition. The particle counting analysis shows that the ? > 95 filter offers a protection factor greater than 4-times that of the ? > 99 filter when evaluated over 60 minutes. The booth pressure monitors provided data that proved to be a valid indicator of system performance over time. INTRODUCTION Designed and installed correctly, enclosed cabs, operator booths and control rooms offer mine workers protection from physical hazards, such as flying rock, debris, and noise, as well as a more comfortable environment in regards to temperature and humidity [1]. But while it may be easier to quantify whether the A/C unit is working (measuring the temperature) or observe whether the cab offers protection from flying debris, it can be somewhat more difficult to quantify its performance in reducing respirable dust hazards. For over 15 years, NIOSH has been conducting applied research to improve the air quality inside of enclosed cabs of mobile equipment [2-5]. This work has led to the identification and mathematical modeling of enclosed cab filtration systems [6]. The same principles that govern the performance of filtration systems on mobile equipment are applicable to stationary enclosures such as operator booths and control rooms [1, 7]. Stationary enclosures are similar to enclosed cabs; however, the volume of the work area can be significantly larger. In addition, workers who perform their duties in stationary enclosures tend to stay within the room for a greater percentage of the day, as opposed to workers on mobile equipment who may enter and exit frequently. Structural integrity can be easier to maintain as well, as there is typically less vibration and stress placed on these compartments as compared to mobile equipment. In addition to offering protection from dust and flying debris, enclosures must ensure that workers have a healthy supply of fresh air to avoid elevated levels of CO2, which are known to cause headache and dizziness, impairing cognitive function. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) states that enclosures should have no more than 1,100 ppm of CO2 when outside levels are 400 ppm [8]. In addition, the American Society of Agricultural and Biological Engineering (ASABE) recommends a minimum airflow for enclosed cabs of at least 42.5 m3/hr (25.0 cfm) per person [9] to ensure an acceptable level of CO2."

Jan 1, 2017

By Jack L. Henry

A laboratory and a pilot-plant-scale investigation has been conducted by the Bureau of Mines to examine possible sources of nitride defects in the production of magnesium-reduced titanium sponge. The production of alpha-stabilized nitride inclusions in hot-rolled titanium plate from air contamination of sponge during its manufacture has been experimentally demonstrated. Magnesium-reduced sponge prepared from air-contaminated magnesium or when contaminated by an air leak during reduction, vacuum distillation, or inert gas sweep, shows very large variations in nitrogen content. Refractory nitrides, delta TiN and epsilon Ti2N have been identified in this sponge. The highest incidence of inclusions resulted from sponge that was reduced by air-contaminated magnesium and from sponge subjected to air contamination during the vacuum distillation cycle and during helium sweep. Air contamination of sponge during the reduction cycle was not nearly as effective in producing inclusions. Tests showed that color and texture may not be reliable criteria for locating defects during sponge inspection. Maintenance of good vacuum-tight integrity, filtration of molten magnesium prior to charging into the reduction retort, and mechanical attrition of sponge to pulverize and disperse nitrides are suggested as practices to lower inclusion incidence in commercial titanium ingots.

Jan 1, 1974

The purpose of this paper is to present the methods used in ground water control and the considerations that affected the development of these techniques. Production at Knob Lake is currently proceeding at depths which may be as much as 200 feet below the original standing water table. In order to produce a more saleable product and to improve operating and maintenance conditions, it is necessary to depress the water table below the mining level. Considerable success has been achieved by drilling deep wells in strategic locations and installing vertical tur-bine pumps at depths of up to 400 feet. This method is especially suitable for operation under severe winter conditions and has reduced the detrimental effects by a far greater extent than other methods of water control, Spring runoff is handled in open sumps, but all other water from four mines, with flows exceeding 16,000 g.p.m., is pumped all year 'round from about thirty-five wells. T HE Knob Lake operation of the. Iron Ore Company of Canada is located on the Quebec-Labrador border, 320 miles north of Sept Iles,

Jan 1, 1965

The purpose of this paper is to present the methods used in ground water control and the considerations that affected the development of these techniques. Production at Knob Lake is currently proceeding at depths which may be as much as 200 feet below the original standing water table. In order to produce a more saleable product and to improve operating and maintenance conditions, it is necessary to depress the water table below the mining level. Considerable success has been achieved by drilling deep wells in strategic locations and installing vertical tur-bine pumps at depths of up to 400 feet. This method is especially suitable for operation under severe winter conditions and has reduced the detrimental effects by a far greater extent than other methods of water control, Spring runoff is handled in open sumps, but all other water from four mines, with flows exceeding 16,000 g.p.m., is pumped all year 'round from about thirty-five wells. THE Knob Lake operation of the. Iron Ore Company of Canada is located on the Quebec-Labrador border, 320 miles north of Sept-lies, a seaport

Jan 1, 1965

By WILLIAM SLOAN

B RITISH COLUMBIA in its mining activities is going ahead by leaps and bounds both in development and production. Mineral production for 1925 was $61,492,242 in value as compared to $48,704,- 604 in 1924, or an increase of about 26.2 per cent. This is a new record. It is the first time in the history of mining in British Columbia that we have gone over the fifty million mark. But we have got in the habit of making new records. The year 1924, with its mineral production of almost forty-nine million was a new record. And I am confident that when the mining history of 1926 is written it will be found that we have established yet another new record and that we can report another 25 per cent increase over 1925. What is the explanation? It is not only that the world is settling down, and settling up, after the war. It is not only that in the rebuilding, the refashioning in which all nations are busily engaged, the metals that come from our mines are needed. More than anything else, at least as far as we are concerned, it is because British Columbia has the resources and the fact that the province has been fortunate in recent years in finding men with the enterprise and the vision required to push ahead the labor of their development. From the ranks of our own people in Canada we have prospectors who have faith, energy and requisite knowledge. They are combing our hills season after season and they are of the type of manhood that does not know the meaning of the word quit. More and more these men are learning the importance of the guidance furnished by geological reports, and to an ever increasing extent such reports, thanks to the valuable work of the Canadian Geological Survey, covering areas little known to man, are made available to them-but it is recognized that in the opening up of our Province, containing within itself 372,000 square miles, it is essential that we should have the cooperation of our cousins on this side of the line as well as of our fellow citizens of the Dominion and of the Mother Country.

Jan 1, 1926

By T. A. Lloyd

"This paper indicates the extent to which Canadian coal mine operators have taken advantage of developments in the science and technology of coal that would allow them to better satisfy changing market demands through improving the properties of their products. At some mines, no attempt is made to alter the coal from its as-mined condition, but at most mines grading into various size ranges and hand-cleaning of lump sizes is undertaken.Over-all, Canada Jags behind most of the other major world coal producers in the proportion of its coals being processed in wash plants. To some extent, this is due to the fact that a high proportion of the coal production satisfies market demands without such treatment. On the other hand, a few of the coal mines in Canada, which produce about 25 per cent of the nation's total coal output, have in operation some of the most modern coal beneficiating equipment available, including jigs, flotation cells, water cyclones, centrifuges, disc filters and thermal dryers."

Jan 1, 1968