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By D. L. Putnam

Snap Lake Mine ?? Complex dyke ore body ?? Underground operation ?? 1.1 million tonnes per annum ?? 1.2 carats per tonne ?? On-site diesel power generation ?? Supply by ice road and air ?? Milestones ? Construction commenced in 2005 ? Commissioning 2007 ? First diamonds August 2007

May 1, 2008

By S. G. Hardcastle, C. K. Kocsis

"Worldwide, metal mines are going deeper. For example, in Canada there are six such mechanized mines planning production at 3000 m (10 000 ft). Working at such depths challenges all aspects of mining including the provision of ventilation to supply an equitable working climate for personnel and machinery.This paper explores the overall challenges of supplying ventilation in Canada’s deepest mines and how the volumes required could be minimized. This is essential because it must be remembered that ventilation and refrigeration are not only costly items to supply, but the magnitude of their cost is also very sensitive to the volume supplied. For the primary ventilation system this is obvious because of the cubic relationship between volume and cost.In deep mines, the main function of ventilation is the removal of heat transferred from the strata and generated by the mining machinery, and the air volumes supplied are designed accordingly. The second consideration is the removal of other pollutants that could be harmful to humans such as diesel and explosive fumes. However, the need for ventilation at its present design levels could be reduced. This paper discusses the implications of such technologies as: tele-remote mining and alternatives to diesel equipment on the magnitude of the volume supplied; ventilationon- demand which recognizes ventilation as a costly and limited resource; plus other aspects, such as the benefits of controlled recirculation, local cooling, and possibly heat rejection back to the strata to gain further advantage from new developments.Furthermore, this paper advances the need to be able to design ventilation systems more cost effectively and how such new advances as process simulators can be used in conjunction with ventilation simulators to explore the diverse options that could affect the air volumes required and provide more realistic economic data upon which to base design decisions."

Jan 1, 2004

By W. T. Irvine

Introduction The property of the Britannia Mining and Smelting Company is on the east side of Howe sound, some twenty miles north of-Vancouver. The camp is served by two settlements, one at Britannia Mines townsite, approximately three miles from the water's edge at an altitude of 2,100 feet, the other at Britannia Beach, on Howe sound. The first discovery of copper ore on the property was made in 1888, but it was not until 1905 that production started. From that year until the end of 1944, production had totalled 732,414,420 pounds of copper and 261,126 ounces of gold from six orebodies, known as the Victoria, Empress, No. 5, Fairview, Bluff, and Jane. No. 8 orebody, with which this paper is concerned, was discovered in 1937 by diamond drilling from the 4100 level, some 300 feet above sea level. Development of this orebody to the end of 1944 had included the sinking of a shaft from the 4000 to the 5250 level, and a limited amount of stoping. This work has delimited the orebody from the 3800 to the 4950 level and has indicated upwards of 1,000,000 tons of copper-zinc-gold ore. It is planned to commence production in the near future, while continuing exploration of the orebody at depth.

Jan 1, 1946

By W. J. Langford

"Conventional design criteria assume that the fracture strength of a structural material exceeds its yield strength. Fracture below the design load is not expected, y et many structures have failed in this way. The causes of the fractures are almost always discontinuities such as cracks and welding defects. Linear Elastic Fracture Mechanics (LEFM or simply 'fracture mechanics') provides an analytical framework for assessing the influence of sharp defects on the load-bearing capability of a structure. Fracture mechanics techniques have reached the point of acceptance by ASME Design Codes for nuclear components, and ASTM Standards now include well-defined rules for measuring fracture toughness. Starting with a simple equation which relates applied stress and crack size, the influence of the material's thickness and yield strength can be calculated. Thus, the size of defect which will cause failure under the applied stress may be determined. Armed with this information, the metallurgist can assess the safety of a structure from the viewpoints of non-destructive testing standards, construction standards and conditions of operation throughout its service life."

Jan 1, 1976

By G. E. Agar, W. B. Kipkie, V. K. Drylie

"This paper describes mineral processing test work on drill core samples from an ilmenite deposit in Terrebonne County just north of Montreal.Mineralogical examination showed that the intimate associa¬tion between ilmenite and hematite precluded their separation. The maximum concentrate grade was therefore limited to 22.9% Ti. Liberation of gangue from the hemo-ilmenite grains occurred around 400 µm, a size which proved to be too coarse for recovery by flotation.Other physical separation techniques, such as elec¬trodynamic, magnetic and jigging, were tried in order to take advantage of the relatively coarse liberation size. An all-flotation procedure and a combination of jigging and flotation yielded similar separations.IntroductionInco Metals Company, through its subsidiary Canico, optioned an ilmenite deposit in Terrebonne County, just north of Montreal, and conducted a drilling campaign to confirm previous geological assessments of the deposit and to provide core samples for mineralogical study. Parts of these core samples were used for mineral processing studies, which will be described in this report. The objective was to identify suitable upgrading procedures, to determine the optimum combination of concentrate grade and recovery, and to provide suitable batches of concentrate for further treatment."

Jan 1, 1980

By W. E. Roscoe

"Mineral exploration properties are those on which an economically viable mineral deposit has not yet been discovered. Such properties are bought, sold, optioned and joint ventured on the basis of their perceived potential for the existence and discovery of a viable mineral deposit. The intrinsic value of an exploration property is therefore based on the exploration potential. One measure of the exploration potential is the amount that can be justified to spend on exploration for a viable deposit.The appraised value method uses a cost approach to value exploration properties. It is based on the premise that an exploration property is worth the meaningful past exploration expenditures plus warranted future costs to test remaining exploration potential. Results of past exploration work are analyzed in order to retain only those past expenditures that are productive in terms of identifying remaining potential. Warranted future costs comprise a reasonable exploration budget to test that potential."

Jan 1, 2002

"9.1. IntroductionThe application of the electron microprobe for in-situ analysis of platinum-group minerals (PGM), first reported by Borovskii et at. (1959) and Genkin (1959), has resulted in a large and growing number of analyses of unidentified PGM. Figure 9.1 charts the increase in the number of reported unnamed PGM from 3 in 1959 to a total of 140 by 1979. All these minerals, with the exception of UN1968-5 and UN1976-1, were analyzed with the electron microprobe.There has been no recognised or consistent manner for reporting these unidentified PGM. The term ""unnamed"" has been used for PGM that are considered to be new species without a name as well as for PGM which have not been exhaustively compared to named and unnamed PGM in order to determine whether they are unique. Many of the so-called unnamed PGM are only unnamed because of poor microprobe analyses or because larger than usual elemental substitutions (e.g. Bi for As) made it difficult to calculate the true stoichiometry. Some of these unnamed minerals have been unnecessarily reported with non-stoichiometric formulae, as discussed by Cabri (1980). Better analytical data should reduce the number of such proposals.Another unfortunate practice, possibly used to by-pass the scrutiny of the Commission for New Minerals and Mineral Names, I.M.A., is to report a ""new"" mineral by referring to it by a name made up of its constituent elements. This has been deplored on a number of occasions (cf. discussion in Fleischer et at., 1976, p. 179), but some journals continue to publish such material. The Commission on New Minerals and Mineral Names has not recognised such ""names"" and these PGM are therefore included in this chapter with other unnamed minerals.A further example of inconsistency in reporting unnamed minerals is the report of a specific ideal stoichiometry with no further details (not even an analysis!); sometimes with a note that this will be reported in greater detail in due course. I have also been guilty of similar optimistic statements and, unfortunately, it is not always possible to follow through. Some authors give data on unnamed minerals in such a discrete manner that their reports are sometimes missed in literature searches."

Jan 1, 1979

By Sami Hindstrom, Travis Orser, John Starkey

"A great deal of effort has been expended in the last 11 years by the authors and others to identify the correct power required to grind ore in a SAG mill, by developing ore hardness variability functions for the ore body to be mined. This paper describes the next step in the SAG design process, which is choosing a SAG mill to accomplish the required specified design performance.At the test work stage, each ore hardness data point is a unique and discreet bit of information that represents the energy required to grind the ore represented by that sample at optimum SAG conditions. When the design criteria are set, it is now considered necessary that the required power draw in the mill chosen be provided at optimum conditions as well.Based on actual 3-ft diameter pilot plant results, we can now show that the grinding efficiency and throughput drop when the optimum load limit is exceeded. Future work is expected to show a similar reduction in efficiency when exceeding optimum speed. Providing specified power by exceeding these optimum conditions is not adequate and leads to a lower cost but underperforming SAG mill.It is possible in some cases to modify a SAG circuit to force it to perform better, but this often takes time, much effort and costly modifications. In most cases the capital spent on a properly sized SAG mill may prevent production losses that would be many times greater over the extended start up period. This is the direct result of choosing the proper SAG mill at the start.INTRODUCTIONThe sequential steps required for the design of any grinding circuit, have changed dramatically in the last seven years. Previously, it was considered necessary to do six foot diameter SAG mill pilot plant tests on representative samples of minus six inch ore (F80), in order to understand design requirements. It can now be shown that this method is costly and not likely to produce the desired result because it is difficult to recover six-inch material from deep within a new mine. The representative nature of the sample is often compromised when the sample is selected."

Jan 1, 2003

By C. T. Bischoff

Introduction Air conditioning is a term which has come into common use only during our generation. By definition, it means the positive and accurate control of temperature, humidity, movement, purity, and component constituents of the atmosphere within an enclosure. Claiming such results for Noranda's ventilation system, or for that of any other large mine, at present would be an idle boast. However, we are working toward that end with considerable success. Modern underground ventilation at Noranda dates back about six years. The later development of air conditioning is in its fourth season, but still in the experimental stage. Various ingenious methods have been devised to cool mines which, because of climatic or geological conditions or depth, are excessively warm. A few installations have been made to warm intake air during the winter months where this is necessary. However, the method currently in use at Noranda is unique in that it accomplishes both ends by one process. This method utilizes the freezing and melting of ice to equalize year-round temperatures. Mining Methods While a discussion of mining methods at Noranda is not proposed in this paper, a brief summary may be in order. The Horne mine of Noranda Mines, Limited, has been developed by six shafts, four of which are now active. The most recent, an internal shaft, extends to 6,000 feet below surface, but all of the ore mined to date has come from above the 3,000-foot level. Figure 1 shows a model of principal ore bodies. The area mined is relatively small in plan, considering its vertical extent and the tonnage per vertical foot. Most of the ore lies within an ellipse about 600 by 1,000 feet. While this has certain advantages, the mining of such massive orebodies has presented many problems.

Jan 1, 1947

By Ralph H. Cleland

Introduction The mines of northern Ontario have entered the class of deep mines. It has often been asked: How deep can operations be carried on? What will the temperature be? This paper is a résumé of a brief survey of rock temperatures made by the Ontario Department of Mines during the year 1932. Present temperatures were recorded and the geothermal gradients that now exist were determined. No alarming situations were found, but many interesting ones have been noted. Northern Ontario mines are fortunately situated as compared with most deep-level mines of the world. The mean yearly temperature, as determined from meteorological records of the Federal Department of Marine, is from 33 to 38 degrees Fahrenheit. The tables on the next page show the temperature range in and about our mining camps ( l ). As no exact figures were obtainable for Kirkland Lake, the data for Iroquois Falls, which is about 50 miles northwest, were taken as applicable there. The figures for Timmins were checked against those of Cochrane and Iroquois Falls and found to be very similar, so that the Cochrane data may be used for the Porcupine camp. The yearly mean temperature is considered to be 33.5 F.

Jan 1, 1933

By T. Holmes

Investigations reveal that the throughput difference between a perfect production day and the average is often on the order of 40%, and that bulk solids handling system deficiencies are the largest (>50%) class of lost opportunities. Root causes for underperformance of elements in material handling systems can often be traced back to the detailed design and even study-stage oversights. To reduce or eliminate bulk solids handling problems in an existing system requires an analysis of troublesome handling equipment – for example, a concentrate transfer chute that experiences plugging, poor flow to the furnace, unacceptable dust generation, and spillage. These problems often lead to significant maintenance costs related to downtime and personnel time. Understanding the cause and cost of flow issues is the first step in troubleshooting the problem. Next, measuring the material’s flow properties is critical to providing design data required to develop a comprehensive scientific solution. In the case of a new installation, the design data is required to properly design the system right first time and prevent flow problems from occurring so that the new equipment works correctly from start-up. This paper highlights the cost of material handling problems and discusses the best approach to evaluate material handling system deficiencies. A case study is given of how Anglo American's operation in Barro Alto Brazil enjoyed a 5-month payback from a bulk solid transfer chute debottleneck project. INTRODUCTION When operating a plant or designing a greenfield or brownfield operation, the intent is to have perfect production days (PPD) each and every day. Money is made by moving material through the plant in a controlled manner to produce the desired product. Mining operations and copper concentration processes are at the most basic level a practice in bulk solids handling (BSH). Unfortunately, many of the project planning steps are overlooked, particularly related to BSH. Investigations reveal that the throughput difference between a PPD and the actual average is often on the order of 40%, and that BSH system deficiencies are the largest (>50%) class of lost opportunities (Wellwood, 2017). Root causes for underperformance of elements in material handling systems can often be traced back to the detailed design and even study-stage oversights. BSH issues are essentially baked into the fabricated plant and left to operations to accept the deficiencies and deal with them for the life of the mine. These deficiencies then become part of the normal operation of the mine and plant.

Jan 1, 2019

By C. P. Browning

Copper, as far as we know, was the first metal used by man, and due to the fact that it occurs in many places in the 'native' state, and also to the ease with which it may be shaped, it has played an important part in the evolution of civilization. Copper tools with inscriptions dating back to 6,000 B.C. are known in Egypt, where the metal probably got its start as a useful material in human hands. Just how far back the use of copper in Canada dates is difficult to say, but it was in use by the Indians in the Lake Superior country long before the arrival of the first white man. For many generations the Eskimos also have used copper derived fr0m deposits of the native metal found in the Coronation Gulf district. Due to the metal's many unique qualities, imperishable with age, ancient implements and utensils are apparently as good today as when they were made, having withstood the onslaught of time probably better than objects of any of the other base metals. Copper alloys so well with other metals that today it is second only to iron in its industrial value. Even at the beginning of the eighteenth century the world's production of copper was probably not more than seven thousand tons a year, with Great Britain producing three-fourths of this. One hundred years ago the mines of the United States, Chili, Mexico, Canada, South Africa, Australia, and Tasmania, which now produce about nine-tenths of the copper of the world, were totally undeveloped. Ln 1926 the world production of copper was approximately 1,658,000 tons, which was seventy thousand tons greater than in the preceding year; but growing demand absorbed the increased production, so that the stock of rough copper throughout the world is comparatively small. Of this huge tonnage of the metal, Canada produced four percent, two-thirds of it emanating from British Columbia, nearly one-third from the Province of Ontario, and the balance from Quebec.

Jan 1, 1927

By Lynn M. Gould

Syncrude Canada operates the largest oil sands crude oil production facility in the world and produces over 13 percent of Canada?s total oil requirements. To do this, Syncrude mines the oil sand in open pits, extracts the raw oil known as bitumen from the sand using water-based processes and upgrades it into sweet light crude oil by fluid coking, hydroprocessing, hydrotreating and reblending. The final product, Syncrude Sweet Blend (SSB) is sent by pipeline to three Edmonton area refineries and then to pipeline terminals which ship the SSB to refineries in Canada and the United States. As parts of the Mildred Lake Base Mine reached their economic life, they were replaced with new facilities at the Aurora satellite mine. Aurora is situated on Oilsand Leases 10, 12, and 34, 35 kilometres northeast of the Mildred Lake facility. (Figure 1) In 2000 the first hydrotransport low energy extraction production train started up at Aurora. A second production train is scheduled for start up in 2003. Open pit mining at Aurora occurs using two hydraulic shovels, two cable shovels, and trucks ranging from 320 ton to 380 ton payload capacities.

May 1, 2002

By S. D. D. Welsby

"A pilot-scale flotation column was used to evaluate four polyglycol frothers at Teck’s Highland Valley Copper Mine. The column was fed with flotation plant feed from the grinding circuit cyclone overflow. Frother dosage was changed by controlled addition to the column feed. Pulp, froth and metallurgical performance were assessed using gas dispersion measurements, water recovery and copper, molybdenum and gangue grades and recoveries. Ranking the frothers based on pulp and froth phase performance using gas dispersion measurements and water recovery yielded contradictory rankings. All of the frothers changed the froth structure in a similar manner such that, at the same structural conditions, they all gave the same degree of separation between water and entrained solids. The only difference between the frothers was what dosage was required to achieve a certain structure. Changes in pulp structure appeared to be related to the critical coalescence concentration (CCC) for each frother. Changes in froth structure were not completely described by the CCC and involved other factors, such as the hydrophobicity of particles in the froth. All of the frothers were capable of achieving the same metallurgical result, just at different dosages. Optimal dosages for the frothers were anywhere from the CCC, where copper and molybdenum grades were maximised, to 2 to 3 or 4 to 7 times the CCC, where copper and molybdenum recoveries, respectively, were maximised.INTRODUCTION Background Due to supply issues, Teck’s Highland Valley Copper (HVC) Mine replaced Dowfroth 250C, their auxiliary frother, with Huntsman Polyfroth W31. The primary criterion for selection was that the new frother gave the same performance as Dowfroth 250C, minimising disruption to the circuit. Frothers play a dual role in flotation, altering the bubble size in the pulp zone and the stability of the froth. A stronger or weaker frother, or a blend of both, will alter the balance between pulp and froth effects and, ultimately, metallurgy. Dowfroth 250C and Polyfroth W31 may not necessarily be the best frothers for HVC from a metallurgical standpoint. There may be a different frother or frother blend that could deliver higher recovery in the bulk roughers."

Jan 1, 2014

By S. E. Jackson, L. J. Cabri

Quantitative determination of gold at sub-ppm concentrations in sulphide minerals is an important component of deportment studies for sulphide-gold deposits. Laser Ablation Inductively Coupled Mass Spectrometry (LA-ICP-MS) analysis is preferred for this application because it rapidly and cost-effectively provides spatially resolved (<20 pm), low ppb concentration data for gold and other elements in mineral grains. Recent advances in LA-ICP-MS analysis include the development and application of elemental mapping. Raw signals from multiple line scans or lines-of-spots are deconvoluted and calibrated to generate elemental maps which provide detailed information on spatial variations of gold and other elements within and between grains.

Jan 1, 2011

By R. Charlier, G. Radioti, J. -P. Radu, S. Delvoie, F. Nguyen

"In order to investigate the fracturing of the bedrock and its possible heterogeneous distribution in situ, four boreholes equipped with double-U geothermal pipes of 100 m long were installed on the campus of the University of Liege (Liege, Belgium) over a surface area of 32 m². The bedrock, which starts at a depth approximately of 8 m, is quite fractured and consists mainly of siltstone and shale interbedded with sandstone.Different geophysical methods are applied at two different phases, after drilling the boreholes and after injecting the grouting material. The first approach consists in lowering an ultrasonic borehole imager (borehole televiewer; Zemanek, Glenn, Norton, & Caldwell, 1970), an instrument that acts as an ultrasonic transducer and receiver, into the boreholes to obtain high-resolution, continuous images with 360° coverage of the local geology and fracturing. Moreover gamma-ray logs of the four boreholes are obtained and inclinometry is conducted.After drilling the boreholes fiber optic cables are attached along the pipe loops and the double-U pipes are installed inside the boreholes. Then the grouting material is injected. The second approach consists in measuring the temperature along the fibers by applying the Distributed Temperature Sensing technique (Soto, Sahu, Faralli, Bolognini, Di Pasquale, Nebendahl, & Rueck, 2007). A laser pulse is injected into the optical fiber and the temperature along the fiber is determined by the intensity of Raman stokes and anti-stokes reemitted signals. Temperature evolution is measured during hardening of the grouting material. Local maxima of the temperature curve are probably due to a local lower thermal conductivity and/or a local larger quantity of grouting material due to gathering of fractures.A detailed fracture characterisation (position, opening, orientation, dip angle) is obtained based on the acoustic signal travel time and amplitude. The fractures are characterised by the same dipping and orientation but significantly vary in number and location in the four boreholes, despite the close distance between them. Gamma-ray data and observation of the cuttings during drilling result in rock identification through depth as well as in determination of the layer dipping. The inclination of the four boreholes tends to be perpendicular to the dipping. The combination of the two geophysical methods as presented provides information useful for the hydro-thermo-mechanical behaviour of the bedrock. The contribution of the thermal behaviour of borehole heat exchangers to bedrock investigation will be further studied by conducting Distributed Thermal Response tests (Fujii, Okubo, & Itoi, 2006). During the tests we will measure the temperature variation thanks to the installed fiber optics. These data will allow us to correlate any anisotropic thermal behaviour to the geological characteristics. The available information could be used for a detailed numerical model."

Jan 1, 2015

By Kilmar Mine

The Kilmar dolomitic magnesite deposit~ in sourhwesr Quebec lie in Grenville Province sedimentary rocks that strike north and dip steeply west. The sediments comprise quartzitic, carbonate and argillaceous members. The middle or carbonate member hosts the magnesite and, like the two other members, has been intensely mewmorphosed. Magnesite occurs as lenticular shaped zones of altered limestone and is mixed with 5 to 30% dolomite crystals. Diopside, serpentine and mica are common accessory minerals. Magnesite appears to have formed from merasomarism of all or part of the carbonate member due to intrusion of hot magnesia-rich solutions. Magnesite is mined from a 490 m vertical shaf1 and is milled and burned into clinkers, which then are shipped 10 pyroprocessing industries around the world.

Jan 1, 1984

By Andy Cole

Barrick Gold recently implemented an oxygen roasting process to treat carbonaceous ore from its Goldstrike property in Nevada. One of the key project challenges was the design of the roaster gas cleaning system, which was driven by the requirements of a strict air permit and the need to achieve very high reliability. The roaster gas systems include multiple stages of wet particulate collection, a dual-alkali SO2 scrubber, mercury scrubbing, CO oxidation and NOx reduction. This paper describes the gas system, the influence of regulations on project implementation, and performance of the system.

May 1, 2002

By J. Visman

"SummaryThis paper is presented as part of a programme to show the steps taken by industry and others interested in supplying a solid fuel of constant quality to 'satisfy a consuming market. The paper deals with the general principles underlying quality control in coal preparation plants, namely, constant quality and close adherance to acceptance limits. It also describes how control of ash content is ""generally hampered by the problem of coal sampling .and the long duration of the ash analysis and how these difficulties may be overcome.Quality control can be effected in several ways. Thorough blending wll reduce variations appreciably, except those of long trend. The latter can be detected by automatic sampling and quick ash analysis. At present, under favourable conditions, a system of half-hourly ash determinations with an accuracy of 0.5 to 1.0 per cent can be realized, to the effect that trends with a 'wave length' of more than two hours cu be eliminated within the limits of accuracy of the ash figures. The general solution of the problem is a combination of blending, accurate sampling, quick ash determination, and statistical analysis of the pattern of ash distribution.The use of statistical methods of analysis, such as the t test and F test, is •discussed at some length in order to emphasize the importance of the correct evaluation of observational data if there is to be confidence in the validity of test results.General ConsiderationsCOAL, as a fuel, is too cheap for a long haul across the country. The limiting distance depends on the price of the local competitive fuels, and, as the price depends to a great extent on quality, so does quality, to the same extent, command the market."

Jan 1, 1952

By J. H. Nantel

Indications are that underground mining is gaining favour with large and small mining companies due to environmental and sustainability concerns. Dramatic changes to mine fill technologies will be needed in order to keep pace with these emerging trends. The industry will be compelled to gravitate toward zero discharge mining operations. Innovative handling of mine tailings will become a focal point in this effort. The challenges are to use a greater portion of the residues and to manufacture a fill with better properties. This is a tall order that can only be addressed through a systematic research and implementation process involving mining companies, universities, research organizations, manufacturers and governments. The mining industry has to be at the forefront of this technology push in mine fills for the future mines. It will also be called upon to lead the way in other research areas. The industry will have to partner with other technology providers: universities, government laboratories and consultants.

May 1, 2007