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Australian coals tend to be young in geological age and high in ash by world standards; preparation of the coal before marketing is almost universal. On the basis of float and sink data from 39 locations in the Eastern Australian coalfields, the coals are placed in four categories representing increasing difliculty in their washability characteristics. These seem to be related neither to the geological age nor the geographical position of the deposit and Hunter Valley coals, for example, span all categories. The influence of crushing on the washability of Australian coals is briefly considered and from limited data it is concluded to be appreciably smaller than for British or North American coals. A strategy for the float and sink analysis of Australian coals is proposed and the influence of washability characteristics on current trends in the selection of separating processes for coking and steaming products is discussed.

Jan 1, 1979

By James Pirie

"The major Archean gold deposits in the Red Lake greenstone belt, which have produced over 374 million grams of gold since 1930, occur near the top of the lower komatiitic to tholeiitic mafic to ultramafic metavolcanic sequence. The upper calc-alkalic mafic to felsic rocks form three discrete and separate ediftces overlymg this lower sequence.The gold deposits are classified according to their stratigraphic or lithologic associations into:1) mafic-volcanic-hosted deposits;2) felsic-intrusive-hosted deposits; and3) stratabound deposits.Group 1 and to a lesser extent Group 2 deposits occur within zones of alteration several square kilometres in extent. The nature of this pervasive alteration can be characterized by comparison of petrochemical data from the altered rocks and their fresher equivalents some distance away. The altered rocks have substantial addition of SiO2> CO2, K2O, As and Sb and subtraction of Na20, CaO, MgO and total Fe. Cr, Ni, Co and Zr appear to have been relatively immobile. Hydrothermal alteration and gold deposition probably accompanied early fumarolic activity and continued during subsequent deformation the metavolcanic sequence, with gold eventually being mobtltzed and concentrated into major vein structures to form the present orebodies. The smaller Group 2 deposits formed by emplacement of felsic intrusions into already altered, anomalously gold-bearing mafic metavolcanics, with the heat from the intrusions setting up parasitic hydrothermal systems which mobilized the gold and deposited it along with minor sulphides in fractures in the cooling intrusions."

Jan 1, 1982

By Francis J. Fratttali, Verda McLendon, Stanley J. Green

"INTRODUCTION During the first phases of the war emergency the shortage of aluminum prompoted the Bureau of Mines to investigate methods for using low-grade bauxites of high silica content and also clays as raw-material sources of this strategic metal. The Bayer process treats low-silica bauxites to provide the industry with a major portion of the purified alumina, which contains very low percentages of silica and other impurities. One of the methods investigated in the laboratories of the Bureau of Mines for low-grade materials is the lime-soda sinter process, which was studied on a pilot-plant scale. In this process, the alumina content of the alumina-bearing minerals Bs made water-soluble by sintering the raw material with limestone and soda. Simultaneously, the siliceous material is rendered insoluble. The sinter is extracted with an alkaline liquor, and the resulting extract liquor is treated as follows to recover the alumina: (1) Autoclaving with lime to remove silica as a zeolitic complex and (2) treatment with CO2 to precipitate alumina as the trihydrate (A1203.3H20). Figure 1 is schematic flow sheet of this process.As the process is cyclic, it is necessary that nearly all of the soda and alumina remaining in the plant liquors after carbonation be recovered. Upon passing through one cycle, these liquors contain 14 to 15 percent NaCO3 2 to 5 percent NaOH, 1 to 3 percent A1203, minor amounts of silica, and, with certain materials such as Pennsylvania diasporic clays, 0.5 to 1.0 percent Na2S04. Approximately 50 percent of the Na20 in these liquors must be returned, as soda ash, to the dry-grinding and raw-materials blending operations. Previous work (6)5/ on sulfate-free solutions demonstrated that two methods for recovering Na20 were feasible, namely: (1) Salting out Na2C03.H20 by evaporation of the carbonated solutions and (2) crystallizing Na2C03.10H20 by cooling the concentrated carbonated solutions."

Sep 1, 1947

By Courtney A. Young

Cyanide is a fast-acting, highly toxic substance but, at the same time, is deemed essential for sustaining life as well 'as our standard of living. In this manuscript, the facts about cyanide are presented beginning with a brief history and definition and ending with a discussion on cyanide alternatives. Other topics include speciation, physical characteristics, toxicity, manufacturing, cyanogenics, cyanide cycle, separation, destruction, and markets including those outside the mining industry. Emphasis, of course, is placed on gold production by leaching and how it is influenced by ore type, mineral characteristics and economics as well as its advantages and disadvantages.

Jan 1, 1998

By CIM Mineral Resource, Mineral Reserve Committee

The CIM Estimation of Mineral Resources and Mineral Reserves Best Practice Guidelines (MRMR Best Practice Guidelines) were prepared by the Canadian Institute of Mining, Metallurgy and Petroleum's (CIM) Mineral Resources and Mineral Reserves Committee (CIM MRMR Committee) to update an earlier version that was accepted by CIM Council on November 23, 2003 (CIM, 2003). These 2019 MRMR Best Practice Guidelines supersede and replace the November 23, 2003 version of the MRMR Guidelines. These 2019 MRMR Guidelines are not intended to be prescriptive and are not intended to provide detailed and exhaustive instructions for preparation of Mineral Resource and/or Mineral Reserve (MRMR) estimates. Rather, they are intended as general guidance to assist professional geoscientists (or equivalent) and engineers (or equivalent) in preparing high quality estimates of MRMR that incorporate sound geoscientific, engineering, evaluation and design practices. They are based on well-established estimation and mine planning principles and are designed to provide general guidelines of best professional practices employed in the preparation of MRMR estimates. Although the 2019 MRMR Best Practice Guidelines are intended for use by Canadian-based mining/exploration practitioners, many of the concepts and practices presented herein are in general agreement with current industry practices in jurisdictions with membership in the Committee for Mineral Reserves International Reporting Standards (CRIRSCO). For this document, persons preparing MRMR estimates are called Practitioners. Preparation of MRMR estimates should be carried out by Practitioners who either hold the status of Professional Geoscientist (or equivalent) or Professional Engineer (or equivalent), or who prepare the estimates under the supervision of a Professional Geoscientist (or equivalent) or Professional Engineer (or equivalent). For the purposes of this document, all references to reporting describe such necessary reports and related documentation that are created as part of the normal-course work flow of preparing MRMR estimates for internal purposes. For clarity, all public disclosure of MRMR estimates made by, or on behalf of, an issuer and intended to be, or reasonably likely to be, made available to the public in a jurisdiction of Canada must comply with the requirements of National Instrument 43-101 Standards of Disclosure for Mineral Projects (NI 43-101), as amended from time to time. At least one Qualified Person (QP) must take responsibility for each part of the estimation process when publicly disclosing the results of MRMR estimates. The intended audience for these 2019 MRMR Best Practice Guidelines includes Practitioners at all levels of skill and experience, government agencies, academic institutions, and the public.

Nov 29, 2019

By Shelby Z. Palya

"The Bureau of Mines was established in the public interest to conduct inquiries and scientific and technologic investigations concerning mining and the preparation, treatment, and utilization of mining-substances; to promote health and safety, in the mineral industries; to conserve Material resources , and prevent their waste; to further economic development; to increase efficiency in the mining, metallurgical, quarrying, and other Mineral industries; and to inquire into the economic conditions affecting those industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the Bureau to ""disseminate information concerning these subjects in such manner as will best carry out the purposes of this Act.""In accordance with this directive, the Bureau reports the findings of its research and investigations in its own series of publications and also in articles that appear in scientific, technical, and trade journals; in proceedings of conventions and seminars; in reference books; and in other non-Bureau publications. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make the kind of list and index presented in this special publication both necessary and valuable. This issue describes reports and articles published during the period January 1, 1975, to December 31, 1979. It supplements the 50-year list of Bureau publications issued from July 1, 1910, to January 1, 1960; 2 the 50-year list, of articles by Bureau authors published outside the Bureau from July 1, 1910, to January 1, 1960; 3 the 5-year lists of publications and articles, from January 1, 1960, to December 31, 1964,, from January 1, .1965, to December 31, 1969,5 'and from January '1, 1970, to December 31, 1974; and the annual ,lists of Bureau publications and articles from January, 1 to December 31, 1975,7 from January 1, to December 31, 1976,8 from January 1 to December 31, 1977, and from January 1 to December 31, 1978."

Jan 1, 1981

By Y Yang

This paper discusses various issues surrounding the metallurgical control for furnaces, especially focusing on processes with long time-constants and æmetallurgical memoriesÆ. Examples will focus on furnaces accepting particulate and sometimes ill-defined feeds, eg submerged-arc furnaces, blast furnaces, secondary scrap smelting operations, recycling operations, waste incinerators, etc. Generally, because of the usually higher metallurgical time constant of these furnaces, these reactors have to be controlled in a feed-forward manner by the use of a hybrid of æblack boxÆ or empirical and ægrey boxÆ semi-empirical first principles metallurgical modelling and simulation techniques in a supervisory metallurgical control capacity.

Jan 1, 2000

By Eleanor Abshire

This bibliography is the second in a series that covers the current technical literature relating to the metallurgy of zirconium. The rapid advance in zirconium technology makes it mandatory that abstracts be prepared and compiled as soon as possible to have maximum value; therefore, the information in this volume is not arranged chronologically. As a service to research and production groups, succeeding bibliographies will be issued as new acquisitions accumulate in the Zirconium Information Center sponsored by the Department of the Navy, Bureau of Ships and the Bureau of Mines at the Bureau's Northwest Electrodevelopment Laboratory, Albany, Oreg. The initial volume, Information Circular 7771, Bibliography of Zirconium, covering 969 abstracted reports and 645 United States and foreign patents, was published in April 1957.

Jan 1, 1958

By A. U. Seybolt, R. E. Honnemon

THE purpose of this communication is to present activity data of nickel in the Ni-A1 binary system that was obtained for oxidation studies in this system. This data has been calculated from previous aluminum activity data at 1000°C1,2 by two types of Gibbs-Duhem integrations. These results should be of particular current interest to oxidation studies of aluminide coated nickel-base superalloys3 as well as other problems. The aluminum activity of Steiner and Komarek1 is plotted in Fig. 1 as a function of composition in Ni-A1 alloys at 1000°C. The dashed parts of the aluminum curves represent our approximate extrapolations from the directly measured regions. In the terminal solution regions (a and L phases) standard parabolic solution functions of the following form are assumed: where i is the component subscript, Ki is a constant at a fixed temperature, and xi is the atom fraction. The resultant nickel activity curve at 1000° C from the Gibbs-Duhem integration4 of the aluminum data is shown in Fig. 1. The solubility ranges of the phases present in the Ni-A1 binary at 1000°C are also denoted at the bottom of Fig. 1. Corresponding values of the nickel activity, aNi and yNi, are listed in Table I at useful compositional intervals. including phase boundary values. The aNi and yNi data listed in Table I are subject to the uncertainties present in the experimental aluminum activity data1 and to deviations from parabolic solution behavior in the terminal solutions. The errors introduced into aNi and yNi due to the parabolic solution assumption are expected to be relatively small (<20 pct of the values given) in all the phases except the liquid phase. Some deviation from parabolic solution behavior in the liquid phase is indicated

Jan 1, 1970

By Juan Mendoza Marsano

"El presente texto revela las primeras transacciones de la venta del oro en el Perú -en tanto se determina su precio a través de un acuerdo denominado""on the spot"", donde el vendedor ofrece sus mercaderías a uncomprador y se acuerda un precio pagado con dinero al contado y de inmediato. Hasta 1914 el precio del oro estuvo determinado o fijado por la denominación de las propias monedas circulantes de oro y sus monedas equi- valentes. Sin embargo, la primera determinación del oro en el Perú surge en Cajamarca, 1553. Posteriormente se describe la circulación de este durante la Colonia, los diferentes métodos de transacción y las especificaciones del contratos de oro, así como los factores que influyen en el precio del oro."

Nov 1, 1978

By A. Galibois, M. Fiset, T. Vo Van

"RÉSUMÉUn groupe de 22 objets prov enant des Forges du St-Maurice a été étudié de façon systématique par analyse chimique et examen métallographique afin de préciser leurs caractéristiques et d&apos;en évaluer la qualité métallurgique.La plupart des échantillons de fe r forgé et d&apos;acier sont hétérogènes tant au niveau structural que composition chimique. L&apos;examen de quelques produits fin is a mont ré qu &apos;on appliquait des traitements superficiels bien que le contrôle métallurgique fût plutôt empirique.AbstractA group of 22 specimens originating from ""Les Forges du St Maurice"" has been systematically studied by chemical analysis and metallographic examination in order to determine their characteristics and to evaluate their metallurgical quality.The bulk of the forged iron and steel samples are heterogeneous from both their microstructure and their chemical composition. Observation of a few finish products has permitted to establish that surface heat treating was applied although its metallurgical control was rather empirical."

Jan 1, 1984

By Arístides Sotomayor

El presente texto señala la importancia del oro a nivel financiero y minero ya que los inversionistas suelen utilizar este metal para obtener ganancias debido al mínimo riesgo existente en la pérdida de su valor comparado con otras divisas. Así, se estima que en el Perú, existen 480 unidades mineras de oro, de las cuales 28 concentran cerca del 90% de la producción nacional, como la Minera Yanacocha, Minera Barrick, Compañía de Minas Buenaventura, Consorcio Minero Horizonte, Aruntani y Aurífera Retamas. Entre las dos regiones que producen mayor cantidad de oro está: Cajamarca y La Libertad ( 38%) y la tercera región es Arequipa, seguida por Madre de Dios (9%).

May 1, 2016

By Nicholas P. Callas

This report presents research results obtained in the investigation of deviation control of boreholes in the rotary drilling process. The approach taken in this research is the passive method of placing stabilizers in the bottom-hole assembly to control deviation. Extensive use was made of the drill string mechanics theories of Lubinski and Woods. Analog, digital and hybrid solutions to variety of boundary value problems were investigated in order to determine the best models for bottom-hole assemblies. Field drilling data was analyzed and the results obtained from various models were compared to the actual drilling results. Various accomplishments of this work have been published in open energy industry literature, with more publications to follow.

Jan 1, 1981

The rocks of Waihi and the surrounding district are almost entirely rhyolitic and ande5itic in character. Sedimentary rocks, with the exception of some surface deposits of clay loosely compacted conglomerate, etc., and one or two thin and broken beds of a very poor lignite, occasionally changed by igneous agencies into a bituminous coal, are almost absent. In the shafts sunk by the Waihi and Grand Junction companies outside the outcropping andesitic area of the Martha Hill, more than one old surface or lake bottom has been passed through. At these points layers of sand, consolidated volcanic mud and tuff, accompanied by numerous broken fragments of imperfectly silicified wood have been enccuntered, but these occurrences may, for the purpose of this paper, be neglected.The youngest rock of the district are rhyolites, probably of Pliocene age. At least three distinct classes of rhyolitic lava, each possessing features of unusual interest, may be made out. None of these, however, is gold-bearing. The youngest flow, a light-coloured, fine-grained rock, is remarkable owing to its enclosing at times fragments of carbonised wood, varying in size from mere specks up to quite large pieces of almost pure charcoal. Rhyolitic tuff is also met with. The rhyolites cover a large extent of nearly flat country east, south, and west of Waibi, here and there rising into barren, stony hills.Below the rhyolites, geologically speaking, but for the most part. forming hills which bound the rhyolitic plain, or rise out of it as isolated patches, come ahdesites of older...

Jan 1, 1902

By J. Durkin

The Bureau of Mines has conducted field studies in coal mines throughout the United States to determine the effectiveness of electromagnetic techniques in locating miners trapped underground following a mine accident. Data from these tests have been used to generate models of expected signal and noise distributions as found above these mines. These distributions have aided in placing the expected performance of a through-the-earth electromagnetic communications technique into a probabilistic framework. Results show that at a 10% false-alarm rate, the expected probability o detecting a miner&apos;s signal" from a depth of 1000 ft is 54% at 500 ft it is 95%. These depths exceed the actual depths of 90 and 50%, respectively, of United States coal mines. Sensitivity studies have shown that at depth of 1000 ft, the probability of detection will improve approximately 2% for each dB of increase in signal-to-noise (SNR) ratio.

By R. W. Raymond

THE sudden death of Dr. Drown, on Nov. 17, 1904, brought to multitudes the pang of personal loss. Of all those who, as students at Lafayette College, the Massachusetts Institute of Technology and Lehigh University, were brought under his influence, not one can have forgotten him, and all will now acknowledge, with an unfading gratitude, what they owe in professional equipment to his wise, clear, skillful guidance, and in character to his sympathetic, stimulating personality. Outside of this wide circle, the experts of both hemispheres will lament the departure of one who, in his department of scientific inves¬tigation, both knew what work was needed, and how to do it so that it needed not to be done again. The older members of the American Institute of Mining Engineers will remember with gratitude the part he took, as Secretary from 1873 to 1884, in promoting the interest of that organization, and in shaping the plan and policy which it has followed with such noteworthy success. And, in addition to all these (though partly included among them), there are a host of friends; who can scarcely think of the public loss by reason of their own. Thomas Messenger Drown was born March 19, 1842, at Phil¬adelphia, Pa. His parents were natives of New England; and. he was the youngest of their three sons. He received his preliminary education in the public schools and the High School of Philadelphia, from which he was graduated in 1859. Be-

Jul 1, 1905

By R. J. Goodman, P. Lafleur

This paper presents a current interpretation and projections of recent statistics on raw materials availability based on familiarity with the Canadian steel industry and its development. Problems and opportunities are recognized and discussed.

Jan 1, 1976

By R L. Brathwaite

The gold-scheelite-quartz lodes of the Wakamarina valley were the most productive of the mesothermal gold-bearing areas in the Marlborough Schist. Most of the production came from the Empire City and Golden Bar mines which worked the Golden Bar lode. Only 134 m of its 1800 m strike length are accessible, in the No.2 level of the Golden Bar Mine. A fault has downthrown the Golden Bar Mine section by = 47 m and displaced it left-laterally by 18 m. The lode is a typical ribbon-banded mesothermal vein, averaging c. 1.75 m wide, and enclosing narrow horses of schist country rock. It is composed of bands of milky æbuckÆ quartz with thin laminae of schist. Scheelite occurs in short strings of grains within quartz on the footwall side of the lode and also in small quartz-carbonate veinlets in the foot wall and hanging wall schist. The lode quartz contains only localised traces of pyrite and arsenopyrite. They are more abundant in the wall-rock schist. &nbsp; The Golden Bar lode lies within a steeply dipping normal fault, which, on its footwall side, is adjacent to a 40 m-wide, shallow-dipping mylonite shear zone. Within 1 m of the lode, the shear foliation has been dragged down to nearly parallel the lode footwall. Wall rock alteration is manifested by a marked increase in K and Rb, which correlate with abundant illite/muscovite and K-feldspar within 2 m of the footwall of the lode. Amphibole, stilpnomelane, and pumpellyite show a progressive decrease towards the lode. As and Sb increase close to the lode, but are at background levels within the lode itself. Enhanced Cr (150-430 ppm) in the quartz, relative to the schists (~40 ppm), suggests that the source hydrothermal fluids passed through and leached mafic rocks, such as the metabasites from the hanging wall of the lode (~400 ppm Cr).

Jan 1, 1995

This paper discusses the social and economic impact of mining, and in particular goldmining, on New Zealand. The range of topics covered and their complexity has confined us in this paper to highlighting the main points of concern û a detailed report is under preparation. A major problem in undertaking this study was the lack of hard data on important environmental, economic and social issues and if there is to be effective planning in the area of natural resource use this situation must be rectified. The following conclusions were drawn: Goldmining was very important in shaping New Zealand&apos;s early social and economic development, providing wealth, employment and impetus for social change.Foreign investment and technology has been an essential element in New ZealandÆs economic development.Mining is a small industry at present by this must not be allowed to obscure its potential to broaden New Zealand&apos;s economic base and provide foreign exchange.With modern methods, development of mineral resources and environmental protection are not incompatible but certain unique and irreplaceable areas must be preserved.There are problems in evaluating mining and other projects because different groups hold different values, and arguments often hinge on the valuation of costs and benefits rather than the technical aspects of the analysis.Mineral exploration is a high risk business and the potential returns must be sufficient to attract capital if New Zealand&apos;s mineral resources are to be developed.A resurgence of goldmining will clearly have obvious benefits for Waihi but the local community must plan carefully for their future.&nbsp;New Zealand will also gain valuable foreign exchange required for higher levels of economic activity.

Jan 1, 1981

By Enzo Palumbo, Joël P. T. Kapusta, François Larouche

In light of the rapid deployment of bottom blowing smelting in China over the last ten years, one has to wonder why it has taken the copper industry so long to adopt ultra-high oxygen enrichment via Savard-Lee type injectors. As early as 1976, Kellogg and Henderson suggested, in their landmark paper on energy usage in the copper industry, that ‘maximum use of oxygen enrichment of process air’ was one of seven ‘energy saving features’ for copper matte smelting and converting. Yet today, shrouded injection and high oxygen enrichment has not been implemented in copper bath smelting outside China and Vietnam. In this paper, the authors explore the reasons why bath smelting processes such as the Noranda Reactor and the Teniente Converter still operate around 40% oxygen enrichment, while the bottom blowing SKS/BBS process typically runs at 65 to 75% oxygen, with all three processes producing white metal. Are there fundamental metallurgical explanations for this striking difference beyond the long-standing skepticism towards high oxygen shrouded injection and its perceived high implementation cost?

Jan 1, 2015