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By H. C. Horwood

INTRODUCTION THE Argosy Gold Mines, Limited, which joined the ranks of active Ontario gold producers during the summer of 1936, holds a group of 21 claims on Casummit lake, in the Patricia portion, district of Kenora, northwestern Ontario. The Company is developing and mining goldbearing quartz veins that occur in a series of greywackes and slates of probable Keewatin age. The writer made a geological examination of the property and the surrounding area for the Ontario Department of Mines during the early part of the field season of 1936. This paper is a report on the general geology, structure, and ore deposits at the mine and is based almost entirely on data compiled during the examination. HISTORY Mineralization was first discovered on the property in May, 1929, by A. F. Hewitt, who, with J. A. Borthwick, decided that the country had prospecting possibilities and commenced work in April. Mr. Hewitt staked, and with his partner, J. Ziyone, still holds the group of claims lying immediately east of the present Argosy holdings. Mr. Borthwick staked six claims, K.R.L. 9,681 to 9,686, inclusive, adjoining Hewitt's on the west and later added claims K.R.L. 9,733 to 9,740, inclusive, to his holdings. F. Fiskness, who was also prospecting in the region, discoveted No. 1 vein on Borthwick's claims, and with his two partners, L. Parth and H. Jones, staked claims K.R.L. 9,758 to 9,763, inclusive, to the northwest of Borthwick's and Hewitt's ground. In July, 1929, the Casey Mountain Operating Syndicate, which held ground to the northwest, secured an option on Borthwick's claims. The Fiskness-Parth-Jones property was added in January, 1930, to protect the west dip of the veins. During the winter of 1930-31, the veins were explored by diamond drilling, No. 2 for a length ?of 900 feet and a vertical depth of from 51 to. 375 feet? and No. 3 .t~ a slope depth of 175 feet. I~ August, 1.931, after the msrallat10n of a miming plant, the Casey Summit Gold Mmes, limited, was incorporated to take over the property from the Syndicate. The Maple leaf Mines optioned a controlling interest in the stock in August, 1933, and on September 17th, 1934, brought a 50-ton amalgamation mill into production. From early in October to December 27th, 1934, when the mill was closed down, 4,094 tons of ore were treated to yield 887.89 ounces of gold and 87 .26 ounces of silver( ! ).

Jan 1, 1937

By Chas. F. Jackson

The work of the Mining Division is divided among seven sections, each in charge of a supervising engineer, as follows: 1. Metal-mining methods section, the supervising engineer of which is also supervising engineer of the Southwest Experiment Station at Tucson, Ariz. 2. Metal-mining research section. 3. Nonmetal-mining section. 4. Coal-mining section. 5. Mine-ventilation section. 6. Mineral-industries survey section. 7. Electrical section. The names of the sections indicate broadly the fields covered by each, and in the following, pages the objectives and type of work of each section will be summarized briefly and their active problems listed. The work clone during the fiscal year 1937 will also be summarized.

Jan 1, 1937

Diversity; what a wonderful topic. Diversity; the condition or quality of being diverse, different, varied to the point that the very word diversity means different things to different people. As one example of diversity the American Science Magazine (April, 1994) contained a light-hearted interview with Dr Noitall who was pushing his case for diversity.

Jan 1, 1996

The Louvicourt Mine is located 600 km north of Montreal in the province of Quebec, Canada. The owners are Aur Resources Inc (30 per cent), mine operator, Novicourt Inc (45 per cent) and Teck Corporation (25 per cent). It is an underground mechanised operation with a total work of 290 employees. Since 1994, the mine production is 11 120 456 tonnes at 3.60 per cent Cu, 1.51 per cent Zn, 26.07 g/mt Ag and 0.96 g/mt Au. At a rate of 4300 tonnes per day 365 days per year. Louvicourt Mine is a copper operation since 80 per cent of our revenue is from copper. The mining method is transverse blasthole stoping, mining primary and secondary stopes. The stope dimension is 15 m wide by 30 m high and 10 m to 80 m long for primary stopes. The secondary stopes are limited at 25 m long. Close to 100 000 metres of production drilling per year is required for 115 mm and 165 mm diameter holes. Backfilling is done with pastefill from the start of the operation in 1994. The binder ratio is 4.5 per cent in primary and two per cent in secondary stopes (80 per cent slag and 20 per cent cement). Development requirement to maintain production was 5000 m from 1996, 1997, 1998, 4200 in year 1999, 3200 m in year 2000 and an average of 2500 m in 2001 and 2002. Typical 6.0 m + 4.3 m, 4.9 m + 4.6 m and 4.5 m + 4.6 m headings. In addition more than 1500 metres of development will be excavated in/under paste backfill before 2004. A total of 60 mobile units are required among which for lateral development (three two boom electric hydraulic jumbos û AC Boomer 322, four electric hydraulic roofbolters û Maclean MEM-928 and AC Boltec PL350 and two anfo loader truck û Dux) and for production (four ITH drills û MTI, one electric hydraulic longhole drill û AC Simba H1357, eight LHD û AC-Wagner ST8-B, 1 LHD ST-1000 and two haulage 30 tons trucks û Dux. The 1 January 2002 reserves are 4.1 M tonnes grading 3.1 per cent Cu and 1.9 per cent Zn at an NSR (Net Smelter Revenue) of $US 53. The operating mining costs were at an average of $US 23 from 1996 to year 2000 and $US 25 in 2001. The operating costs ranged from a low of $US 0.41 per pound of copper in 1999 to a high of $US 0.49 per pound of copper in 1998.

Jan 1, 2002

By G. P. Marino

The "conductivity ", Kr, of a spherical void in a linear temperature gradient due to radiation is calculated by integration of the general expression for diffuse radiation between two gray surfaces of arbitrary orientation. The spherical geometry allows an exact evaluation of the phenomenon without resorting to up-proximate expressions for the radiant heat flux. The resulting expression for Kr is three quarters of the approximate value obtained by Loeb. IN the determination of the thermal conductivity of porous materials such as sintered UO2 and ThO2 fuel pellets, the magnitude of the thermal conductivity in the pores due to radiative heat transfer across the pore, Kr, may be important in assessing the total conductivity of the pellets. Loeb' has calculated Kr for various pore geometries by approximating the net flux of heat between two surfaces of temperature difference AT as 4eT~AT and obtained: K,=4yoet3odp [1] where a is the Stefan-Boltzmann constant, E is the emissivity of the radiating surface, To is the average absolute temperature of the region across which radiation occurs, dp is the largest dimension of the gap in the direction of heat flow, and y is a geometric factor. That is: y = 1 for laminar pores and cylindrical pores with axes parallel to the heat flow direction, y = 2/3 for spherical pores, y = /4 for cylindrical pores with axes perpendicular to heat flow direction. It was the purpose of this work to obtain an exact expression for K, in spherical pores by integration of the general expression for the net heat transfer between two incremental areas on the surface of a spherical pore. This procedure yields a value of Kr 3/4 of that obtained by Loeb. I) CALCULATION OF Kr Fig. 1 illustrates the general geometry which defines the problem. The total emissive power for a gray body is given by: E = EoT4 [2] where E is the radiated energy per unit area of the radiation surface per unit time, T is the absolute temperature, o is the Stefan-Boltzmann constant (o = 5.67 X lo- '' watt per sq cm-"K1), and E is the emissivity of the surface. Although Eq. [2] gives the exact expression for the total emissive power of any gray body, all practical problems involve the net exchange of thermal radiation between a body and surrounding bodies. The two major considerations in the solution of such problems are a) shape and relative position of the surfaces and b) the emissivities of the surfaces. In this work it shall be assumed that all incremental areas on a pore have the same emissivity and, further, that little or no reflection occurs (i.e., the radiation hitting a surface is either absorbed or transmitted). Thus, the solution of the stated problem requires only that consideration a be satisfied. Consider two incremental surface areas dA 1 and dA2 of the same material in a general orientation to one another. Let dAl be at temperature TI and dAz be at T2. Fig. 2 illustrates the geometrical parameters involved. That is, 71, is the normal of dA, n2 the normal of dA2, r the line connecting the centers of each area, 81 the angle between nl and r, and Q2 the angle between 7,2 and r. Using Eq. [2] and the Lambert cosine law of diffuse radiation it is easily shown that:293 WdAf- dA, = ecr T*------^fpi------" dAidA2 [ 3a 1 and

Jan 1, 1970

By Paul M. Tyler

Graphite occurs in many places in the United States, but previous to 1914 the domestic production amounted to only 15 to 20 per cent of the natural graphite consumed in this country. Including artificial, graphite, the proportion was about 25 per cent. During the World War the production of both natural and artificial graphite increased until, in 1918 it, contributed more than one-half of the available supply, and since 1919 the proportion has not fallen below 40 per cent. Except during the war period, however, this apparently increasing independence has not been due to any large increase in production from domestic mines. It simply reflects a larger output of artificial graphite and reduced imports of Ceylon lung and chip, grades which have never been produced in substantial quantity in the United States. DOMESTIC DEPOSITS3 American graphite deposits, though numerous and often large, are characteristically low-grade. They constitute an abundant source of potential supply, but in normal times they have proved relatively costly to work, and even at the same price the various products have never been able wholly to displace certain imported qualities, notably crucible grades from Ceylon and pencil graphite from Mexico.

Jan 1, 1929

By Sydney H. Ball

A QUARTER of a century ago, a pessimistic Belgian financier in conversation with the founder of the Belgian Congo, that great ruler, Leopold II, emphasized the danger to the colony should the synthesis of rubber be discovered. The king replied, "I do not worry. The Congo has had its ivory period; it now has its rubber period. Tomorrow it will have that of its mineral wealth; eventually that of agricultural products." That "tomorrow" arrived some twenty years ago. Through her mines the Belgian Congo has survived the present depression, and her mines for the next decade will safeguard her. The Congo, in turn. is the surest foundation industrially and financially of Belgium itself. In few, if any, political units is mining as dominant as in the Belgian Congo. In 1930, 1931 and 1932 mineral products represented respectively 67.9 per cent. 70.5 per cent and 59.3 per cent, of the total exports. In 1933 for each white person in the colony, there was produced about $1,675 worth of gold, diamonds, copper, tin ore and minor mineral products and in 1930 the per capita production, notwithstanding the larger population, was almost $2,000.

Jan 1, 1934

By DONALD H. McLAUGHLlN

Few factors have had more influence in maintaining the strength and stability of the United States than our persistent habit of providing .checks and balances to the dynamic powers of free enterprise on the one hand and to the controls and guidance exercised by the State on the other. .Indeed, it is this same concern for matching forces against each other that has given our republic its ability -to preserve a democratic basis of life for its citizens, and yet maintain a ,government that is able to protect the rights of all and to resist and minimize the danger of excessive concentration of authority. Our current efforts to clarify the nation's mineral policies and to define more clearly the role that the governmental agencies should play in conjunction with the functions of private -enterprise again reveal the desirability and advantages of maintaining our traditional controls. At times, the equilibrium has been temporarily disturbed by too great enthusiasm for one or the other of these basic concepts. Sooner or later, however, the balance has been restored by the healthy opposition that is always created by excesses of one sort. At the current stage in our history, the swing toward undue enlargement of the powers of the State seems to have gone dangerously far and we would be untrue 'to our traditional behavior if the group that must demonstrate the virtues of free enterprise did not rally to its support with the utmost earnestness.

Jan 1, 1949

By . José Arango O

El presente trabajo describe las nuevas técnicas de lixiviación aplicadas en Cerro Verde ante un posible desabastecimiento del mineral en un futuro y por ende, ocurra un alza de costos en el tota de la producción. En este sentido, se implementa nuevas técnicas en el el sistema como la lixiviación con curado, la lixiviación en capas delgadas y el retratamiento de los pads, las cuales prolongan la operatividad de sus plantas y mejoran el nivel de ingresos de divisas.

Nov 8, 1984

By Luis Quevedo

En el proyecto Pangui, localizado al sureste del Ecuador de las provincias de Morona Santiago y Zamora Chinchipe, se descubrió un cinturón de pórfidos de cobre con tendencia N-S y un skarn de cobre. Esta zona se localiza entre el flanco occidental de la Cordillera del Cóndor y las estribaciones orientales de la cordillera real cercanas al borde limítrofe con el Perú. La mayor parte del área está cubierta por selva y las pendientes son abruptas. En la zona no hay una buena infraestructura de carreteras. En este sentido, el presente texto describe las actividades de Gencor y Billiton durante 6 años, así como los resultados de un año de actividades de Corriente/Lowell en los proyectos Warintza, Mirador y Panantza.

Apr 24, 2001

By Alexander May

The U.S. Bureau of Mines investigated the application of oxidation-reduction potential (ORP) and pH measurements to environmental studies of mining and mineral processing wastes, and developed a computer program to estimate the concentrations of species of lead present in samples from a lead processing waste site. The methods and techniques for the ORP-pH measurements were investigated using known standard solutions made in the laboratory, samples from a ferric oxide waste disposal pond at a rutile production plant, and samples of well water and stream water from the lead processing waste site. ORP values were measured from 5 to 80 °C, from pH 1 to pH 12, and at various ratios of oxidant to reductant. The ORP-pH values can help identify valence values and species of ions present, including those of major, minor, and trace concentrations, and also indicate possible reactions at various pH values. The ORP measurements versus temperature yield data from which thermodynamic values can be calculated. The application and limitations of these measurements are discussed, and a brief discussion of the computational program to identify species of lead is presented.

Jan 1, 2010

By Madan M. Singh

It is estimated that through 1975, there were 1.69x109 m2 (418 000 acres) of urban land threatened by potential subsidence due to mining with a value of over $12 billion (19;3 dollars; USBM, 1979). With increased coal production to meet the energy needs of the nation, both these figures may be expected to increase. Hence greater attention to controlling surface damage due to subsidence is merited. In fact, the Surface `lining Control and Reclamation Act of 1977 (SMCRA) (Public Law 95-87) mandates that underground coal mining operators "adopt measures consistent with known technology in order to prevent subsidence causing material damage to the extent technologically and economically feasible, maximize mine stability, and maintain the value and reasonably foreseeable use of such surface lands, ..." The term "subsidence," as used in this paper, implies the total phenomenon of surface effects associated with the mining of minerals, and not only vertical displacement of the surface as is sometimes inferred in the literature.

Jan 1, 1984

By J. Drew Potts

The U.S. Bureau of Mines identified respirable dust sources and controls on four continuous auger mining sections, two with relatively low dust levels and two with high levels. Factors adversely affecting dust levels included auger equipment design, continuous haulage, and low seam height. Dust controls included ventilation practices and spray systems. Maximizing airflow seemed to reduce dust levels most. Air leakage and shock loss can be reduced by constructing stoppings with brushed-on mortar containing fiberglass and by keeping areas between curtains and ribs free from obstructions and storing equipment not essential for face activities in outby crosscuts. Curtain configuration, setback distance, and installation can also affect dust levels. Use of both blowing and exhausting curtains is the most effective configuration. Setbacks from the face should not exceed 15 ft. Installing brattice curtains at least 5.5 ft from ribs, when entries are 26 ft wide, minimizes velocity head. Installing curtains tightly against the mine roof and floor helps maintain a forward airflow movement in the center of the mine heading; curtain overlap can create a tighter seal. The wet-auger spray system also effectively controls dust, provided the mine is already exercising good ventilation practices.

Jan 1, 1989

By Jennifer S. Riefenberg

The U.S. Bureau of Mines conducts basic and applied research related to predicting, eliminating, and/or controlling rock bursts in underground hard-rock mines and coal bumps in underground coal mines. An important element in this research is the development of a reliable and efficient microseismic source location technique. This report presents the results of a Bureau study to develop and evaluate a new algorithm to locate microseismic events based on the Simplex method, a powerful linear programming technique. The technique was tested on both field data and simulated data. Microseismic event source locations obtained with this new Simplex-based algorithm were shown to have less error than those locations obtained using a least squares method. It was concluded that the Simplex approach to source location of microseismic events can be used effectively in microseismic monitoring.

Jan 1, 1989

By Thomas M. Barczak

This U.S. Bureau of Mines report is intended to assist coal mine operators in the selection of longwall supports by providing advanced guidelines for performance testing and standardized test documentation to facilitate support comparisons. These advanced guidelines culminate in a series of proposed tests to evaluate (1) support resistance characteristics, (2) stiffness characteristics, (3) leg mechanics, (4) stability, (5) load transfer mechanics, and (6) structural integrity. The Bureau has conducted extensive studies on shield mechanics to identify boundary conditions that induce loading in support components, which is often not included in current testing techniques. This report discusses influential parameters that affect support behavior and provides insight into how components are loaded and what conditions produce the most severe loading. Testing philosophies and techniques in both active and static frames are discussed. Proper methods for determining support resistance are described and instrumentation requirements for advanced performance testing are provided.

Jan 1, 1989

By Robert R. Walden, LeMont West

K ENTUCKY'S first acid-grade fluorspar flotation Kmill, shown in Fig. 1, was placed in operation Aug. 1, 1952, by the Pennsylvania Salt Manufacturing Co. at Mexico, Ky. During 1951 a critical shortage of acid-grade fluorspar developed and it became necessary for the company to produce part of its fluorspar requirements. In 1951 the company purchased the Crider and Lennen metallurgical fluorspar mill and an adjacent stockpile of tailing at Mexico, Ky. The tailing, assaying about 26 pct calcium fluoride, originated from log washer and jig mill concentrators in the area. As the mill did not have a fluorspar dryer or convenient rail facilities, the company leased the Burleson concentrator at Marion, Ky., where these facilities were available. At Marion, Ky., on the Illinois Central Railroad, dry acid-grade fluorspar is transported direct to the company's Calvert City, Ky., hydrofluoric acid plant. The Mexico flotation plant was reconditioned and designed to produce acid-grade fluorspar from the jig tailing stockpile. The new plant flowsheet is shown in Fig. 2. The ore feed, old tailing, which contains 10 pct of waste rock and coarse gravel assaying approximately 8 pct CaF,, is bound together by sticky clay

Jan 1, 1955

By R. W. Raymond

Edward Cooper was born in New York City, Oct. 26, 1824. His father, Peter Cooper, to say nothing of manifold reasoils for fame as an inventor and philanthropist, deserves to be remembered as a pioneer in the establishment .of public schools ; and it is not surprising that. he sent his son to one of the democratic institutions in which he was himself so ardently interested. From the public school Edward Cooper went to Columbia College, where he made the acquaintance of Abram S. Hewitt, who was first his tutor, afterwards his traveling companion, brother-in-law, business partner and life-long friend.' For twenty years I was the consulting engineer of the firm of Cooper & Hewitt, and also connected with the work of the Cooper Union, in which they were both deeply interested and faithfully active. On the basis of the intimate knowledge thus gained, I venture an estimate of Edward Cooper's character and career which, if not fully comprehensive, may facilitate a juster estimate than would be reached by the student of those data which the modesty of the man permitted to be placed upon public record.

Jan 1, 1907

By Roger C. Ilsley

The $2.1 billion Milwaukee Water Pollution Abatement Program (MWAP) requires the construction of several miles of underground openings at depths up to 350 feet for the conveyance and storage of sewage and storm water overflows. The system will include approximately 27km (17 miles) of deep tunnels ranging from 3m (10 f t.) to 9m (30 f t.) in diameter, 26 shafts and a pumping station cavern. The facilities will be located primarily in Silurian Age dolomites of the Niagara Group. The rock is characterized as competent with vertical to sub-vertical orthogonal jointing and predominantly thin shale bedding planes. The site investigation was carried out incrementally, commencing on an area wide basis, becoming site specific as facility plans were developed. To achieve cost savings through uniformity and continuity, a computerized data bank was established. Software was developed during the initial stages of the program for the production of borehole logs, structure contour maps, geologic profiles and summaries of data for statistical evaluations. This paper discusses in general terms the collection, compilation and presentation of data necessary for the characterization of the rock mass.

Jan 1, 1984

By Norman L. Wimmler

Active placer mining in Alaska began near Juneau in 1880, but the first gold rush did not start until 1896; then the discovery of the Klondike brought gold seekers from all parts of the world. A few of the newcomers were experienced miners, but the majority knew nothing whatever of placer mining. Even those who were placer miners of much experience found entirely new conditions, notably frozen ground, that presented many difficult problems. As a result, numerous methods of mining and of thawing frozen ground were tried. From these trials the practice described in this bulletin has been developed. All known placer fields in Alaska have been mined to some extent, and some have been virtually exhausted. In most districts, however, there remain large quantities of low-grade gravel and also some small isolated areas of comparatively rich gravels which could not be successfully mined because of adverse physical conditions. These districts are now the scene of most placer mining, including dredging, hydraulicking, drifting, mechanical methods of open-cut mining, and ground sluicing (or booming) followed by " shoveling-in."

Jan 1, 1927

By S McGregor, J Sharp, I Entezari, T Boulter

The piezocone penetration test (CPTu) is one of the primary screening tools used by the mining industry to evaluate whether tailings are susceptible to liquefaction (static or cyclic). Liquefaction analysis using the CPTu is influenced by the fines content of the soil, and most CPT screening tools empirically use the behaviour type index (Ic) to correct for fines. The issue with this approach is that such empirical relationships have been developed using data collected from natural soils and their applicability to different tailings deposits needs to be studied. In this paper, we explore the use of machine learning to develop a site-specific model to estimate fines content of tailings using gamma piezocone penetration testing (GCPTu) measurements. The results are then compared to the fines content derived from the soil behavior type index (Ic) proposed by Robertson and Wride (1998). A dataset of paired GCPTu and laboratory results were compiled and a support vector machine (SVM) algorithm was employed to calibrate a model to estimate tailings fines content from in-situ GCPTu data. We calibrated GCPTu data to geotechnical 75 μm fines content measured in the laboratory. The geotechnical fines content is the fines content as a percentage of solids. The development dataset was comprised of paired GCPTu-laboratory results collected in 2009-2019 from a mining area with predominately clay mineral and quartz sand tailings. Results show that the developed model predicts the geotechnical 75 μm fines content of the studied deposits with 7.8% error. The Ic based method estimates the fines content with 31% error. Evidently, the Ic method is not applicable to the studied tailings deposits. It is appreciated that many tailings fines do not contain clay, and that the success on this program may not be repeatable everywhere. However, the authors wish to point out that the application of site-specific machine learning algorithms may be used to significantly improve empirical geotechnical parameters.

Jul 1, 2021