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By H. C. Gunnings, C. O. Swanson

"The Sullivan mine; at Kimberley in southeastern British Columbia; is the largest silver-lead-zinc mine in the Empire and one of the largest in the world.The original discovery was made in 1892 by four prospectors. Until 1899, when the branch line of the Canadian Pacific railway from Cranbrook to Kimberley was completed, little work was done on the property. In 1900, systematic development was started, and during the next 3 years 5,000 tons of ore was shipped to the smelters at Nelson and Trail. By 1903, some 300,000 tons of ore was developed, and a smelter was started at Marysville, about 5 miles from the mine. However, this smelter closed down in 1907 because of metallurgical difficulties after treating 75,000 tons, and the property came under the control of the American Smelting and Refining Company. An option on the property was taken in 1909 by the Consolidated Mining and Smelting Company of Canada, who exercised their option in the following year. During the next 5 years by selective mining and sorting 188,000 tons of high-grade ore was produced and shipped to Trail. This tonnage came from the upper levels, about 4,600 to 4,800 feet in elevation. At the same time, deep drilling down to the 3,900-foot level showed the presence of an immense body of complex ore. In 1915, the main adit-the 3,900-foot level-was started, and by 1919 this had been driven a distance of 2 miles to develop the ore above this level. Meanwhile, progress was being made in overcoming the milling problems. An interesting account of this work was written by the staff ( 4). In 1923, the first unit of the present concentrator was erected, with a capacity of 2,500 tons a day, and thereafter the rate of production increased rapidly. In 1934 it was around 8,000 tons a day, and to date a total of about 30,000,000 tons of ore has been sent to the mill. In recent years, a considerable part of the production has come from levels between the 3,900-and 3,350-foot, which were opened by an internal incline shaft started in, 1930. In 1942, tin was added to the products separated at the concentrator."

Jan 1, 1954

By Tony B. Szwilski

"The efficiency of operation and life of an advancing longwall coalface depends, to a great extent. on the face-end roof strata conditions and the stability of the gateroads. The factors that influence the rate of closure of gateroads are examined, in particular the gateside pack and the coal rib (crush) pillars. The performance of mechanized packing systems is briefly discussed. Gateroad deformation surveys were carried out at two coal mines to determine the influence of the rib pillar width on gateroad stability; also, the influence of the gateside pack on the immediate roof and floor strata is analyzed based on strata bed displacement measurements from instruments installed in the gateroad and pack-hole of a longwall advancing face operating in a thick seam (7.55 m). Concluding, an evaluation of the fac e-end systems examined is given and recommendations made f or the most suitable rib pillar width. face-end geometry and roof strata reinforcement.IntroductionKevword s: Coal mining, Pillars, Rib pillars, Ground control, Longwall mining, Gateroads , Packing systems, Roof control. The face-end region of a longwall advancing face is the center of mining activity, being the turn-around point for the coal cutting machine. and the place of gateroad formation and movement of special face-end supports. The design of face-end layouts can be aided by knowledge of strata control parameters, such as the effective loading of the immediate roof strata , convergence of the roof and floor, magnitude and distribution of fractures in the roof strata around the face-end , optimum placement of supports, coal seam thickness and strength characteristics, geometry of layout and interaction from neighbouring workings. Generally, the gateroad is formed by one of three face-end methods: (a) advanced headings, (b) in-line system (gateroad formed at the face) or (c) conventional ripping with or without stable elimination (also halfheading). The quality of gateroad is influenced principally by the face-end system employed, standard of gateside pack and width of pillar. A good standard of gateroad is generally achieved by employing the half-heading face-end system, the gateside pack and coal rib pillar having comparative support/ yield (stiffness factor) characteristics. However, the halfheading is often not favoured due to face operation restrictions."

Jan 1, 1981

By S. Banisi, J. Marois, A. R. Laplante

"This paper compares the behaviour of gold and ore in the grinding circuit of Hemlo Mines Ltd. Particular attention is given to grinding kinetics, classification behaviour, and liberation. For grinding kinetics, laboratory grinding of gold flakes and silica, 840 µm to 1200 µm in size (14/20 mesh), was also performed to provide a standard for comparison and to study in a controlled environment the mechanisms of breakage, folding , smearing and impacting.Grinding kinetics were characterized at laboratory scale with breakage and selection functions. The breakage function showed that 75% of gold disappearing from the 840 µm to 1200 µm class reported to the 600 µm to 840 µm; this figure is much higher than for silica (46%) or most other minerals, and implies that comparatively fewer fine fragments are produced from the breakage of gold flakes, on account of gold's malleability. The selection function of silica was four times that of gold. At plant scale, the ratio of the selection function of ore and gold increased from 6 for at 50 urn to JOO pm to 20 at 500 um to 1000µm.Observation of original flakes and their fragments with the scanning electron microscope showed that the main mechanism of ""grinding"" from the 840 µm to 1200 µm to the 600 µm to 840 µm class was folding rather than actual breakage. This was confirmed by a measure of individual flake weight. The postulated breakage cycle is that relatively globular flakes become increasingly serrated through grinding; they can then regain their original shape through folding and reflattening into cylindrical and spherical shapes, as the majority does; however, some fragments will at this point undergo actual breakage. Photograhic evidence is presented to support the proposed mechanisms.Smearing of gold unto silica was observed when silica was ground after a gold, and embedding of silica into gold flakes when gold was ground after a silica. Both mechanisms occur whenever gold and harder minerals are jointly ground, and result in ""unliberation"" of gold. It is postulated that smearing of gold onto other minerals plays an important role in explaining how gravity recovery can increase over-all gold metallurgy, especially when used ahead of flotation.Classification of gold in the primary hydro cyclones takes place at a much finer cut-size than ore, 20 µm vs 57 µm. This and the slower grinding kinetics result in high gold circulating loads in the primary loop, 6700%, and a gold content in the primary cyclone underflow (PCUF) is twenty-four times that of the ore. The gold size distribution for primary cyclone overflow is much finer than that of the ore, although they are essentially similar in the PCUF.Liberation, or more accurately ""gravity recoverability"", was assessed with a 7.5 cm (3 in.) Knelson concentrator. It varied between the thirties for the primary mill discharge and two cyclone overflows, to highs of 89% and 92% for the PCUF and secondary mill discharge."

Jan 1, 1991

By A. E. M. Warner, A. Vahed, P. J. Mackey

In the decade 2002 to 2012 some 6.7 million tonnes of new copper concentrate production capacity was brought on line, corresponding to 2 million tonnes of contained copper. This increase in concentrate supply necessitated the commissioning of a number of new copper smelters as well as the modernization and/or expansion of existing plants to meet the demand. This paper gives an overview of the copper extractive industry, reviews recent copper production trends and changes in the copper industry, including an examination of pyrometallurgical and hydrometallurgical technology developments. WorleyParsons has supported a number of the projects involved in these developments and this role is briefly discussed. The paper introduces a number of ideas related to possible future directions of the copper industry.

Jan 1, 2014

By Doug Ashbury

Diamond Miners? Challenges ? Remote ? 300 kilometres from Yellowknife ? Sub-Arctic conditions ? permafrost, climate ? No power ? No all-weather roads ? Ore bodies difficult to find ? Caribou, fish of special concern ? Communities with low education, little experience, but high expectations ? Major investment required ? Diavik C$1.3 billion

Apr 1, 2005

By Bennett McLaughlin

The Penna Shaft is the deepest single?lift shaft in North America. AGNICO-EAGLE started sinking the Penna shaft in 1995 with a hoisting plant capable of hoisting 1 800 tonnes per day from a 2 240-metre deep shaft. Exploration success at depth lead to the replacement of the existing double drum hoist by another double drum hoist capable of hoisting 7 000 tonnes per day. The use of another double drum hoist, instead of a Blair Multi-Rope winder, to hoist 24,5-tonne skips was only made possible by lowering the safety factor. This paper describes recent experiences at Penna and in South Africa, and examines the possibility of extending the double drum hoisting system to a depth of three kilometres.

May 1, 2003

By Bruce A. McFarlane

"I WOULD LIKE TO SAY how honoured I am that I have been invited to participate in this panel discussion. I have taken the liberty of narrowing my topic somewhat so that instead of speaking on the Sociology of Professions as a whole I will speak on one aspect of it, that is, on Manpower Problems in the Minerals industry of Canada, with some reference to a new social role for the professionals engaged in this industry. This probably means that I will be encroaching on areas covered or to be covered by other speakers, but I hope that when I do so I will do so from a slightly different vantage point. That is, from a sociological perspective rather than from a historical, industrial, business or professional perspective. I plan to divide my discussion into three areas, namely: (i) problems of ownership and control; (ii) environmental problems; and (iii) manpower and recruitment problems. I do not plan nor am I able to provide clear-cut solutions to the various problems I raise under these three headings. Rather, I hope that my discussion of the problems may form the basis for an extended discussion here and elsewhere. Because of the limitations of time, I will only briefly discuss the first two problem areas noted above – (i) ownership and control and (ii) environmental problems - and I plan to concentrate on the manpower issue."

Jan 1, 1972

By R. S. James, S. P. Goff, A. E. Armitage

"Abstract - Oxide-facies banded iron formation in the Third Portage Lake area is hosted by ultramafic and calc-alkaline volcanic rocks and related sedimentary rocks of the Archean (2.8 Ga) Woodburn Lake Group, 80 km north of Baker Lake. These rocks record at least two phases of metamorphism/ metasomatism. Greenschist facies metamorphism, in the temperature range of 370°C to 520°C and at pressures above 2.3 kbar, has affected all rocks on a regional scale. Later mineralization and alteration of banded iron formation (BIF) and associated volcanic rocks resulted from metasomatic fluids which carried Mg, K, Ca, S, As, Cu and Au. These fluids were confined to ductile to brittle, cross-cutting and layer-parallel micro-shears developed in the thickened hinge region of a shallow plunging recumbent fold. Metasomatic reactions yielded cummingtonite + biotite-bearing assemblages which are associated with strongly mineralized iron formation. Pyrrhotite is the dominant sulfide phase and occurs within ductily deformed iron formation where it pervasively replaces magnetite. Minor fine-grained chalcopyrite and arsenopyrite generally occur as inclusions within pyrrhotite and recrystallized magnetite, and rarely as individual grains. Pyrite is restricted to brittlely deformed iron formation, and to the contact between iron formation and altered ultramafic rocks, where it is associated with quartz veins. Pyrite typically replaces pyrrhotite. Native gold is associated with both pyrrhotite and pyrite, but higher gold concentrations are associated with pyrite. Grunerite/Ca-amphibole + stilpnomelane and sparse pyrrhotite and pyrite characterize weakly mineralized iron formation. Within adjacent ultramafic rocks, metasomatic reactions yielded assemblages of interlayered Ca-amphibole + biotite, and talc + Ca-amphibole + carbonate + biotite. K-Ar geochronology on metasomatic biotite from mineralized BIF yielded a 1791 ± 32 Ma age.An epigenetic model is favored for the emplacement of gold. The age of the gold mineralization in the Third Portage Lake area is uncertain, but may be Proterozoic based on the preliminary isotopic age and by analogy with Proterozoic gold deposits elsewhere in this part of the Churchill Structural Province."

Jan 1, 1996

By A. J. R. Smith

"CANADA'S ECONOMY TODAY is about two-fifths larger than it was six years ago, as measured by the total volume of production of goods and services. Such an achievement has been a rare phenomenon in Canada's first one hundred years. Excluding the forced-draft expansions which took place under war-time conditions, perhaps only the first decade of this century recorded a performance of greater dimensions, when, with massive immigration, the opening up of the West and a powerful array of well-de-signed development policies, the country was looking forward confidently to a great future of nation-building in the twentieth century.What makes Canada's over-all economic advance since 1961 all the more remarkable is that six years ago there was virtually no one in this country who anticipated an expansion of such dimensions. Back in the buoyant conditions of 1956-57, perhaps such an achievement would not have seemed beyond our grasp. After 1957, however, Canada stumbled through an extended period of slow economic growth, high unemployment and substantial and widespread under-utilization of its productive capacity. By the early 1960's, conditioned by the emergence of substantial, persistent and pervasive slack in the economy, t h e r e were few Canadians bold enough to anticipate that their economy was about to embark on a Great Expansion. However, this •is, in fact, what occurred. Beginning early in 1961, Canada moved forward into a sweeping advance which grew into the longest and largest peacetime business expansion in Canada's first century as a nation -a truly great expansion by any standard of measurement. This strong thrust has moved Canada into the front ranks of over-all economic expansion among the industrially advanced nations in the 1960's."

Jan 1, 1970

By R. S. James, S. P. Goff, A. E. Armitage

"Oxide-facies banded iron formation in the Third Portage Lake area is hosted by ultramafic and calc-alkaline volcanic rocks and related sedimentary rocks of the Archean (2.8 Ga) Woodburn Lake Group, 80 km north of Baker Lake. These rocks record at least two phases of metamorphism/ metasomatism. Greenschist facies metamorphism, in the temperature range of 370°C to 520°C and at pressures above 2.3 kbar, has affected all rocks on a regional scale. Later mineralization and alteration of banded iron formation (BIF) and associated volcanic rocks resulted from metasomatic fluids which carried Mg, K, Ca, S, As, Cu and Au. These fluids were confined to ductile to brittle, cross-cutting and layer-parallel micro-shears developed in the thickened hinge region of a shallow plunging recumbent fold. Metasomatic reactions yielded cummingtonite + biotite-bearing assemblages which are associated with strongly mineralized iron formation. Pyrrhotite is the dominant sulfide phase and occurs within ductily deformed iron formation where it pervasively replaces magnetite. Minor fine-grained chalcopyrite and arsenopyrite generally occur as inclusions within pyrrhotite and recrystallized magnetite, and rarely as individual grains. Pyrite is restricted to brittlely deformed iron formation, and to the contact between iron formation and altered ultramafic rocks, where it is associated with quartz veins. Pyrite typically replaces pyrrhotite. Native gold is associated with both pyrrhotite and pyrite, but higher gold concentrations are associated with pyrite. Grunerite/Ca-amphibole + stilpnomelane and sparse pyrrhotite and pyrite characterize weakly mineralized iron formation. Within adjacent ultramafic rocks, metasomatic reactions yielded assemblages of interlayered Ca-amphibole + biotite, and talc + Ca-amphibole + carbonate + biotite. K-Ar geochronology on metasomatic biotite from mineralized BIF yielded a 1791 ± 32 Ma age.An epigenetic model is favored for the emplacement of gold. The age of the gold mineralization in the Third Portage Lake area is uncertain, but may be Proterozoic based on the preliminary isotopic age and by analogy with Proterozoic gold deposits elsewhere in this part of the Churchill Structural Province. Copyright"

Jan 1, 1996

By Ben D. Thompson

Cemented Paste Backfill has proven to be of critical importance to the operation of a number of Canadian mines, primarily due to the rapid backfilling rate this method permits. In order to improve the efficiency of this backfill system (i.e. optimize binder contents, fill fence design, and the employment of two stage filling strategies) there is a requirement to better understand its geomechanical behaviour. In response, in-situ experiments have been conducted in long-hole stopes to quantify the evolution of total earth pressures and pore pressures at a series of instrumented points within both the core of the backfill and close to fill fences. The deflection of fill fences as a result of paste loading has been measured and additional instrumentation has also been employed to measure cement hydration, negative pore pressures, and blasting induced vibrations within fresh and cured paste backfill. Installing geotechnical instrumentation within an open long-hole stope can be an extremely complex procedure and this paper details the methods that have been successfully employed. Preliminary results are presented, and the pressures induced by backfill with differing binder contents, at a number of different in-stope locations are considered.

May 1, 2009

By G. W. Davies

"IntroductionThe development of British Columbia's northeast coal deposits, represents the single biggest industrial undertaking in British Columbia's history.As a result of this development, several thousand jobs were created, hundreds of millions of dollars in new tax revenue and billions of dollars in new foreign exchange began flowing into Canada.The Northeast Coal Development began in 1981 with the signing of sales contracts to ship a total of 6.5 million tonnes of metallurgical and additional quantities of thermal coal annually to Japan over a 15-year period. The current long-term agreements contain provisions for extension to 20 years.The sales contracts with a group of Japanese steel mills were signed by two Vancouver-based mining companies, Quintette Coal Limited and Teck Corporation. The agreements followed years of exploration and negotiation beginning in 1968.The first shipment of coal from Quintette and Teck's Bullrnoose Mine was transported by BC Rail and Canadian National Railways to the Ridley Island coal port in the fall of 1983."

Jan 1, 1992

By John H. Fowler

"Barytes is one of the major components of drilling fluids used in oil and gas well-drilling. This mineral's close association with the petroleum industry bestows it with a commodity status not enjoyed by many other industrial minerals. Approximately 85% of world barytes production is used as a weighting agent in oil and gas well drilling while the remaining 15% is consumed mainly in the manufacture of barium chemicals, glass and as a pigment, filler or extender.Barytes mining began in Nova Scotia around 1865 and has continued until the present. Currently there are three barytes producers in the province one exporting pharmaceutical-grade barium sulphate and the other two supplying drilling mud-grade barytes to the offshore. Several barytes exploration and development programs are underway with excellent possibilities that Nova Scotia deposits will supply a significantly larger share of the drilling mud-grade barytes used in east coast drilling programs.Currently there is renewed interest in barytes activities in Nova Scotia because of its use as a weighting agent in drilling flu ids used in offshore oil and gas drilling programs.This paper reviews the use of barytes by the well drilling industry; outlines the history of barytes mining in the province, progressing to present-day exploration, development and production activities underway in Nova Scotia; and concludes with the market potential for Nova Scotia barytes."

Jan 1, 1986

By C. W. Drury

It is practically fifteen years since stellite was first introduced into industry, and since then the progress made in its manufacture has been so rapid and the number of successful applications so varied that it was considered a review of the more important phases would be of general interest. Stellite is a cobalt-chromium-tungsten alloy, containing approximately 2. 75 per cent carbon. The high percentage of carbon is necessary for the requisite hardness and resistance to wear at ordinary temperatures, whereas the tungsten is essential to impart hardness at a red heat. Chromium imparts hardness and strength, and cobalt renders the alloys more resistant to oxidation. The metals cobalt and chromium are completely soluble in all proportions, both in the liquid and solid state, the equilibrium diagram showing a minimum in the solubility curve at approximately 50 per cent cobalt and l,340°C. Cobalt and tungsten are completely soluble up to 40 per cent tungsten, which is beyond the limit of the; tungsten content of stellite alloys. In the presence of carbon, carbides are formed, which are essential in stellite possessing good cutting or wearing properties.

Jan 1, 1930

By B. C. Legg, G. L. Tiley

"Many of the ore bodies presently being developed are in remote locations and are, or will be, served by electrical power supply systems of limited capacity.The largest single components of the electrical systems of an underground mine are usually the production hoist drives; the power demands of these drives vary continuously throughout each hoisting cycle.Before 1970mine hoists were driven by either wound rotor induction motors or DC motors in conjunction with motor generator sets.Static Power conversion equipment now costs less to purchase and install and is claimed to be more efficient than motor generator sets. On the debit side, however, it can adversely affect the hoist motors, it operates at relatively low power factors, and it produces harmonic currents.This pa per discusses the effects of static equipment on both DC motors and AC power systems, and evaluates the relative consumption of the three classes of drives."

Jan 1, 1993

By John J. Laffin

"IN THE BOOK that has been rated the best seller of all time, it is predicted that man will earn his livelihood by the sweat of his brow. Apparently man has accepted the statement as a challenge and has been attempting to refute it ever since, as he continues to transfer the workload to his inanimate servants - the many types of machines and other labour-saving devices that are available to assist or perform for him in the normal tasks of the day. The history of the evolution of the use of energy takes us back to primitive man, who existed in a very low energy environment, the only energy available being his own muscle power. Although man took a great leap forward when he discovered fire, which was used for lighting, heating and cooking, he still depended upon his own muscles for power. Early man's greatest achievement was probably the invention of the wheel, which permitted him to utilize the muscle power of animals. While still in a very primitive state when viewed from the perspective of the twentieth century, man, with fire and the wheel, had achieved a standard of life far exceeding that of his predecessors. Looking beyond the very basic elements of human energy, fire and the muscle power of animals, we find the next additions of energy coming from man's mastery of other elements of nature. The Phoenicians utilized the power of the wind and the Romans adapted the energy of falling water to the water wheel."

Jan 1, 1972

By E. Paransky, M. Rigaud, G. Paschek, S. Palco

Some of the negative impacts of carbon addition on the strength of castables are yet to be overcome in order to fulfill its potential benefits for oxidation resistance. This paper reports the results of recent studies conducted at CIREP on the effects of different types of carbon additives on the thermo-mechanical properties of magnesia-based castables. Experimental techniques included measurements of the hot modulus of rupture (HMOR), hot modulus of elasticity (HMOE), as well as the wedge-splitting test (WST). The comparison of evolving microstructures was carried out employing scanning electron microscopy with microanalysis attachment (SEM/EDS) and X-ray diffraction (XRD). HMOR values of 12 MPa at 1300°C have been reached in MgO-Si02-C castables containing up to 7% carbon.

Jan 1, 2004

By O. Kangal, G. Önal, G. Bulut, A. Gül

The recovery of copper and cobalt from the ancient copper slags, located in Küre-Turkey, is investigated. Fayalitic type of ancient copper slags containing 1.41% Cu, 0.53% Co and 53.16% Fe were subject to the experimental study. Magnetic separation, gravity concentration and flotation test were conducted. The results of magnetic separation and gravity concentration were not satisfactory. However, a concentrate containing 9.57% Cu could be produced with 44.7% recovery by flotation. Copper and cobalt that remained in the flotation tailings was recovered by roasting with sulfuric acid followed by hot water leaching. Complete cobalt dissolution was observed in 1 hour of roasting at 150°C and 3:1 acid/slag ratio, whereas the copper recovery was 83%.

Jan 1, 2004

By V. K. Karra

A mathematical model for the performance of a vibrating screen is developed in terms of an oversize partition curve. This is a normalized curve for any assemblage of particles presented for screening when their size is normalized with respect to the 50 per cent passing size (d50 ) under the prevailing screening conditions. Based on the throughfall aperture (hT) of the wire mesh on the deck, the effects of oversize (% >hT), half-size under (% <0.5 hT), deck location and feed rate were evaluated using the existing screen sizing information. All these variables and also the near-mesh (1.25 hTx 0.75 hT) content (%) of the feed affect the d50. Performance data from different decks of a double-deck screen with various feed rates, size distributions and screen apertures were used to evaluate the near-mesh factor. Effects of wet screening and material bulk density are also incorporated in the model. This generalized model is useful for the simulation of a multiple-deck screen. It furnishes the sieve analysis information of all the deck output streams and therefore has a potential use in the over-all circuit evaluation when used in conjunction with relevant crushing and grinding performance models. An example illustrating the prediction capabilities of the model is given.

Jan 1, 1979

By A. Hussain

PAPER NOT SUBMITTED FOR PUBLICATION

Jan 1, 1987