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By N. Campbell, W. T. Orvine

The metalliferous deposits of British Columbia are largely confined to that portion of the Cordilleran province lying west of the Rocky Mountain trench. Massive sulphides in the coastal area carry important copper •values together with lead and zinc and are composed mainly of pyrite which replaces schists or shear zones. The massive sulphide ore of the interior, on the other hand, contains lead and zinc with little copper. Pyrrhotite rather than pyrite is... the dominant metallic and deposition took place through selective replacement of sedimentary beds.

Jan 1, 1960

By B. A. McKee, T. Adamcewicz

For a capital expenditure of only $46,000, Caland Ore Company has successfully converted its three dry grinding center peripheral discharge rod mills to dry grinding ball mills. The conversion has resulted in a significant capacity increase, operating cost reductions and in-plant environmental improvements. This paper describes why and how• the conversion was made.

Jan 1, 1972

By G. A. Pinsky, Pickard M. K

"IntroductionTWO METHODS of mucking have been used in sinking C shaft, the five-compartment production shaft of the Yellowknife property of Giant Yellowknife Gold Mines, Limited:(a) Band mucking during the original sinking in 1949 and 1950 (l); and(b) Mechanical mucking with the Cryderman shaft mucker during the recent deepening in 1954.This paper briefly describes the recent deepening and compares the performance figures of the two sinking operations.PlanningProduction planning in 1952 showed that it would be advisable to deepen C shaft in 1954 to provide for three new production levels and the installation of an underground crusher. To complete the required shaft work it would be necessary for a shaft crew to deepen the shaft about 500 feet, to partly excavate three level stations and a crusher station, and to cut a station for the loading pocket. Figure 1, a vertical section of the lower part of the shaft, shows the details of the deepening programme.During the planning period, Giant had a rather small supervisory staff and at the same time was experiencing a heavy labour turnover. As it was obvious that production would suffer if the sinking crew were recruited at the mine, it was decided that the merits of contracting-the shaft sinking to an independent contractor should be investigated."

Jan 1, 1955

By G. G. Hatch

FOLLOWING World War II there was an urgent need for the development of domestic sources of ilmenite to take care of the expanding needs of the titanium dioxide pigment industry. In addition, there was the interest by the pigment manufucturers and others in titanium metal. Prior to the war the pigment industry in the United States had obtained its major tonnage of ilmenite, analyzing 55- ?60 per cent Ti02, from India. However, as a result of the shipping situation which developed during the war, the pigment manufacturers had to consider the use of lower grades of ilmenite located on this continent .and several companies undertook extensive exploration programmes to locate and develop such orebodies. Probably the most significant deposit that was found as a result of these ?programmes was the orebody .at Allard Lake, Quebec, owned by the Quebec Iron and Titanium Corporation. This ?Company was formed in 1948 by the Kennecott Copper Corporation and the New Jersey Zinc Company to mine this ilmenite ore and treat it in electric furnaces to produce titanium dioxide slag for the pigment industry and iron for the steel industry.

Jan 1, 1956

By A. M. Elmahdy, T. Hirajima, M. Farahat

"Separation of molybdenite from chalcopyrite is mainly achieved through flotation technique to raise their grades up to 25% to be extracted in smelters. However, molybdenite recovery and grade obtained from this process is not satisfactory in most cases due to the natural hydrophobicity of both minerals. The influence of conventional heat treatment on pure chalcopyrite and molybdenite minerals was investigated. X-ray diffraction, TG-DTA and XPS techniques were applied before and after heat treatment. The results showed phase changes for both minerals. Magnetic separation experiments of single and mixture of both minerals at several magnetic intensities were made. For single mineral experiments, 100% molybdenite recovery was obtained at all experimental conditions as non-magnetic fraction whereas ca. 100% chalcopyrite recovery was achieved under certain conditions. In case of 1:1 binary mixture, 87% and 83% molybdenum and copper recoveries, respectively, were obtained. The increase in chalcopyrite magnetic recovery is related to the formation of more magnetic phases as confirmed by characterization techniques.The objective of this study is to increase the magnetism of chalcopyrite to make its separation from molybdenite by magnetic separation possible and to understand the mechanism behind it. These results indicate that it may be possible to upgrade molybdenite ores using heat treatment followed by magnetic separation to the required grade by smelters which is difficult to attain by froth flotation and the other techniques."

Jan 1, 2016

By C. O. Campbell

THE recognition by C. W. McKee, field engineer for Springer Sturgeon Gold Mines, Limited, in the fall of 1940, of the economic possibilities of a small outcrop of baryres near Pembroke, in Hants county, Nova Scotia, followed by aggressive exploration and development by the Company, has placed Canada for the first time in its history in the position of becoming a major producer of barytes and its products. In past years, production of this mineral in Canada has been unimportant. Thus the coral output from 1885 ro 1933, inclusive, amounted to only 41,027 short tons, following which there was no production until 1939. Deposits in Nova Scotia, and particularly in the Lake Ainslie district, Cape Breton, have been the main source of supply, with a production between 1866 and 1925 of 31,689 tons. Following the examination of the outcrop of baryres near Pembroke by Mr. C. W. McKee in October, 1940, the area surrounding it was trenched, and, as this work gave encouraging results, a diamond drilling programme was commenced. A grid system was laid our and sixteen holes aggregating 2809.3 feet were put down, spaced at 100-foot intervals, the deepest hole being 300 feet. This drilling outlined a body of high-grade baryres over 600 feet long and 200 to 250 feet wide, with an average depth of 120 feet and estimated to contain well over one million tons of ore. The limits of the body were reached on the west, north, and southwest, but the drilling was suspended before the eastern limit was determined. Quarrying operations, and construction of a 100-ton mill, were commenced in February, 1941. The mill was placed in operation on May 29th, and on June 15th, eight months after the initial discovery, the first shipment of 2,500 long rons of milled baryres was made to Trinidad, British West Indies.

Jan 1, 1942

By I. A. Menshikh, S. A. Kotov, N. L. Shinkarkin

All the cycle for conversion of natural and reprocessed uranium of ROSATOM’s “TVEL” Fuel Company is concentrated at the Siberian Chemical Plant. Conversion capacities are located on two sites, i.e. the Radiochemical Plant, which refines feedstock, and the Conversion Plant, which produces uranium oxides and uranium hexafluoride. Liquid radioactive waste arising in the process, after pretreatment, is transferred to a dedicated national operator for underground disposal. Environmental strategies pursued by the Fuel Company involve the introduction of process solutions intended to eliminate liquid radioactive waste and convert it into a solid phase. In the 5–7 years coming, work will be performed to refurbish and upgrade conversion facilities of the Siberian Chemical Plant that will principally change its radioactive waste management scheme. This paper describes the current waste management scheme and sets out planned schemes for management of natural and reprocessed uranium waste, which will be implemented in the refurbishment of conversion facilities of the Siberian Chemical Plant. The new technologies for the management of liquid radioactive waste from uranium conversion described in the present paper have an undeniable advantage over the current technology mainly due to significantly less environmental harm.

Jan 1, 2020

By Ian M. F. Arnold

"Occupational health programs and their role in improving the quality of working life in the mining industry are discussed. Attention is directed to some problems peculiar to the Canadian mining industry. Factors affecting program development are reviewed, as well as parameters affecting cost-benefit analyses.IntroductionThe quality of working life in the mining industry is a more important consideration than in many other industrial environments because of the very nature of the undertaking. It was a strange paradox of the 1960s that preventive maintenance programs for machinery and equipment were well accepted, whereas the concept of ""preventive people medicine"" was basically ignored. Fortunately, there seems to be a swing toward the development of occupational health programs in many sectors of the business community; however, there is a noticeable lack of consistency and uniformity for thought among the members of the mining industry. The blame for this lack o f progress in the occupational field cannot be entirely attributed to the industry, but must also rest with (for the most part) apathetic and inadequately trained physicians. This latter problem is slowly improving with the growing recognition that a well-planned and executed occupational health program may improve the quality of working life for mining employees and their families.There are a number of factors which relate to occupational health in mining, and its effect on working life quality. Included among these are:1. Community isolation.2. High accident risks.3. Occupational disease risks.4. Production demands and the state of the economy.5. Government regulatory requirements.6. Travel demands.These, and others, reflect on all levels of the mining industry. To examine how these factors can be moderated by an occupational health program, it is necessary to first review the rationale for such a program and some of the costs related to it."

Jan 1, 1983

By J. McCreedy

"The addition of Portland cement to hydraulic sand fill has resulted in the production of stable and self-supporting cemented sand fill. The use of cemented fill in the mines of The International Nickel Company has resulted in substantial economies in timber requirements, de-creased dilution of ore and greater flexibility in mining methods.Coupled with special mining techniques, it has permit-ted mining by both cut-and-fill and shrinkage stoping methods to much greater depths than heretofore. The use of cemented sand fill has permitted revisions to undercut-and-fill mining which have significantly improved the efficiency of this method.Automated mixing systems have been developed for preparing cemented sand fill in surface sand plants on a continuous throughput basis. Control of cement-sand mixtures is obtained by the use of a mass flow measuring system and weighing cement feeders."

Jan 1, 1966

By Wael Abdellah

Mine haulage drifts are the primary access to the mining blocks of an orebody in a multilevel mining system of a tabular ore deposit. The stability and functionality of haulage drifts are thus crucial to the success of a mining operation. Drift instability could lead to serious consequences such as injuries, production delays and higher operational cost. In this paper, the performance of the haulage drift stability is evaluated on the basis of the primary rock support system comprising 1.8 m resin grouted rebars in the drift walls and 2.1 m long bolt in the back. Two failure criteria namely the extent of Mohr-Coulomb yield zones around the drift, and linear elastic brittle shear failure are adopted and compared, with respect to lower level and same-level mining and filling sequence in the vicinity of the haulage drift. The case study is one of the #1 Shear East zone of the Garson Mine in Sudbury, Ontario. Random Monte Carlo (RMC) technique, which has been previously established to assess the haulage drift stability, is employed in this investigation. The RMC technique is used in conjunction with finite difference modelling software FLAC for random assignment of model input parameters in the FLAC grid. Deterministic model results reveal the drift behaviour in terms of deformation (convergence) and mining-induced stress distribution. Comparison between the two different criteria is carried out to determine which method is most suitable in evaluating unsatisfactory drift performance. The results are presented in terms of probability of instability and categorized with respect to failure condition and mining step. It is shown that the brittle shear failure condition based on linear elastic response calls for enhanced support system at a later mining step than what Mohr- Coulomb yielding condition does. The paper presents a detailed discussion of the stochastic analysis results.

Jun 1, 2012

By J. G. Pearson, F. H. MacDougall, A. G. Galley

The difference in age, host rock lithology, alteration and style of mineralization indicates a fundamental difference in the format ion of gold deposits in the Flin Flon and Amisk Lake areas. The Flin Flon area contains early quartz-sulfide-gold veins fo rmed within intermittently active fractures and later plutonic hosted deposits thought to be generated in a porphyry system. In the Amisk Lake area two types of gold occurrences are recognized: I) gold-quartzcarbonate- sulfide veins within or flanking fault zones and 2) structurally and stratigraphical ly controlled zones of dissem inated and vein type sulfide-gold mineralization within extrusive and intrusive rhyolite and dacite porphyries. Both types of deposits are set within supracrustal rocks. are accompanied by intense alteration haloes and were formed prior to the major deformation event suggesting an early, epigenetic hydrothermal origin.

Jan 1, 1986

By J. P. Harrison, R. Roostaei

"In this paper we investigate the consequences of using conventional triaxial peak strength criteria in the polyaxial stress conditions that occur around the end of a long circular underground opening. A series of 3d boundary element analyses were performed using Examine3D to determine the stresses induced around the tunnel in different in-situ stress conditions. To discuss the applicability of a triaxial strength criterion in failure prediction, strength factors were computed for both the Ottosen polyaxial strength criterion and the triaxial Hoek-Brown criterion. Assuming that the Ottosen criterion is an accurate indicator of strength factor, the discrepancy from this value due to the Hoek-Brown criterion is the error in prediction.In order to simultaneously show the error in prediction and actual strength factor, a quantitative bivariate colour scheme is used to visualize the results. This allows rapid identification of regions with large error, and where either unsafe or overly conservative conditions occur. We show how the inappropriate use of triaxial criteria rather than polyaxial criteria leads to an under- or over-estimation of strength factor, and can result in uneconomic or unsafe design. Extending the analysis to different in situ stress regimes shows how the in situ stress conditions affect the assessment."

Jan 1, 2015

By O. Hall

STOPING at Noranda" is a sequel to "Mining at Noranda". "Mining at Noranda", presented in 1937 (1), sketches Noranda's history, metallurgical problems, exploration, mining methods, mining details, pillar extraction, and costs. "Stoping at Noranda" deals in greater detail with our stoping, the use of sub-level drifts instead of benches, and the drilling out of the stopes with jointed rock drill steel and diamond drills. Sun-LEVEL DRIFT STOPING: Sub-level drift stoping is almost universal throughout the mine and is the standard sroping method in both sulphide ore and rhyolite flux ore. The features that have led to the adoption of this standard are: (1) Continuous symmetrical drilling in sub-level drifts with no delay for blasting. (2) Large-tonnage blasts Saturday night after the drillers have left. (3) Comparative freedom from gas and smoke during the working days. ( 4) The daily safety achieved by having all stope drilling done in drifts. (5) The safety and security achieved by drilling out stopes, floors, and pillars before there is any weighting or cracking.

Jan 1, 1939

By Grant Small, Jessica Kinal, Christopher J. Greet

"The conversion from an electrochemically reactive grinding media (forged steel) to a more electrochemically inert alloy (high chrome white iron) not only reduces the wear rate of the grinding media, but also has an impact on the grinding chemistry. Typically the grinding chemistry becomes more oxidising, with less reducing Eh values and more dissolved oxygen in the pulp. There is also a decrease in the EDTA extractable iron, which is an indication of the change in the media corrosion. These changes are indicative of alterations in the surface chemistry of the minerals that the operator is trying to separate. For porphyry copper ores the changes in the pulp and surface chemistry not only affect the copper sulphide minerals, but also impact the iron sulphides (i.e. pyrite and pyrrhotite). Generally, with more oxidising pulp chemical conditions during grinding there is an increase in the oxidation of the iron sulphides which renders their surfaces hydrophilic, thereby depressing flotation. This leads to improved selectivity for copper sulphides against iron sulphides.INTRODUCTIONPorphyry copper deposits are the dominant source of copper that is mined today to satisfy global demand. These style of deposits typically contain one percent copper mostly as chalcopyrite, but may contain other copper bearing minerals (for example, bornite, chalcocite, azurite, malachite), small quantities of pyrite and quartz. Porphyry copper deposits also contain economically significant quantities of gold, silver and molybdenum. Interestingly, the majority of the world’s porphyry copper deposits are concentrated along tectonic plate boundaries (Figure 1)."

Jan 1, 2016

By H. Fuchs, W. Hilger, E. Prosser

"The Lone Gull discovery of Urangesellschaft Canada Limited was made in 1974 as a result of extensive exploration activities for unconformity related uranium deposits in the Baker Lake area of the Northwest Territories. The structurally controlled mineralization is hosted in Aphebian metasediments and intrusive granitic stocks located approximately 2 km south of the unconformity between the Lower Proterozoic Aphebian and the Middle Proterozoic The/on Formation.The original discovery was made with a helicopter mounted radiometric system during systematic prospection over the unconformity. Diamond drilling was first carried out in 1977 and continued, with an interruption in 1981, to the present. A total of 25,500 metres and 199 holes have been drilled and outlined three ore zones. Preliminary geological reserves are estimated at some 16 million kgs. U30 8 at an average grade of approximately 0.4%.IntroductionUrangesellschaft initially entered exploration in Canada as a participant in joint ventures in 1968, and was incorporated in Canada in 1974 as Urangesellschaft Canada Limited. Subsequently, UG was among the first companies to apply exploration criteria developed from the Athabasca Basin, namely the Middle Proterozoic unconformity over Archean/ Aphebian basement, for selection of exploration targets in the geologically similar Thelon Basin.The Baker Lake area in the Keewatin District of the Northwest Territories was selected from the extensive Thelon Basin because it had the best accessibility (Fig. 1). The hamlet of Baker Lake located close to the geographical centre of Canada, is largely an Inuit settlement with a population of approximately 1,100 inhabitants. The distance from Baker Lake to the Lone Gull property is about 80 km. Baker Lake is connected to the tidewater of Hudson's Bay via Chesterfield inlet and is serviced by scheduled domestic flights several times weekly from Churchill, Manitoba, about 650 km to the south."

Jan 1, 1986

By Roy O. Ifill, W. Charle Cooper, Alan H. Clark

"Queen’s UniversityIn representative, run-of-mine samples from the Panel and New Quirke mines of the Elliot Lake uranium district, Ontario, brannerite, ametamict uranous titanate, occurs in microscopic grain-aggregates which display wide variations, both in textural habit and in the relative proportions of brannerite, titania polymorphs and/or “uraniferous titania”. As is widely documented, much of the brannerite occurs as trellis-like arrays of laths and needles pseudomorphing rutile oranatase. In some cases, the laths and needles are cemented by coffinite. Brannerite, with an average composition of (U0.629Th0.039Ca0.20)(Ti2.199Fe0.13)O69contains =3 wt% Th and is distinctly Ti-rich relative to the ideal composition, UTi2O6. Much of the Si reporting consistently in electron microprobe analyses (between 1 wt%and 5 wt%) is tentatively attributed to contamination by the quartz-sericite matrix, and a minor proportion is attributed to the presence of coffinite intergrowths. “Uraniferous titania” (average par-tial composition by weight: 10.8% U, 0.3% Th,32.9% Ti) is considered to represent an intermediate stage in the conversion of titania to brannerite.The leaching behaviour of brannerite in its different modes of occurrence was studied qualitatively by the rotating-disc (polished section) method in H2SO4and HCl solutions at 25° to70°C. Redox potential was not measured. The progress of the dissolution of the individual brannerite crystallites and grain-aggregates was monitored by optical and scanning electron microscopes. Regardless of its morphology and texture (laths or needles, reticulate or blocky),brannerite is not readily leachable. Regardless of the process conditions, the rate-controlling step appears to be the initial leach-pit formation. These pits expand radially through the aggregate as leaching proceeds. This dissolution mode is independent of the relative amounts of brannerite and titania, i.e. the type of grain-aggregate. Secondary coffinite intergrowths are readily leachable and enhance the overall leaching kinetics of brannerite by accelerating leach-pit formation. These data provide, for the first time, information on the controls on the leaching of the uraniferous phases which dominate the lower-grade ores in the Elliot Lake district."

Jan 1, 1996

By M. Goto, F. Kubota

"In this study, we show the successful separation of rare earth metals, which are indispensable elements for the high-tech industry, from a solution containing a metal mixture by using a liquid-liquid extraction and liquid membrane based on ionic liquids. We employed newly synthesized N, Ndioctyldiglycol amic acid (DODGAA) as an extractant for rare earth metals. The DODGAA exhibited a high affinity for rare earth metals such as Y, Nd, Eu and Dy and the extraction efficiency was greatly enhanced in ionic liquids (ILs). Furthermore, stripping of the metals was readily achieved by using an acid solution. INTRODUCTIONRare-earth metals have important applications in cutting-edge technologies employed in the electronics, information technology, and automobile industries. As Japan does not have many natural metal resources, maintaining a steady supply of imported rare-earth metals is important. The total amount of rareearth metals imported into Japan was 19,000 tons/year in 1996, and this amount increased to 40,000 tons/year over the following decade (Kramer 2010). Japan is now one of the world’s major importers of rare-earth metals (Kramer 2010). However, more than 90% of the rare-earth metals imported into Japan come from China, the world’s leading supplier of rare-earth metal resources, due to their low costs. This situation made us realize the importance of a second resource of rare-earth metals: “urban mines” or discarded electronic waste. Rare-earth metals are generally separated from their natural ores by solvent extraction. However, since urban mines have different metals and the concentrations of rare-earth metals are usually low, highly efficient separation and recovery methods are required for rare-earth metals.Recently, ionic liquids (ILs), which are molten salts at room temperature, have attracted considerable attention since they are novel, environmentally friendly solvents (Kubota & Goto, 2006; Han & Armstrong, 2007). The use of ILs in liquid-liquid extraction of rare-earth metals has been reported (Kubota et al., 2012). In some cases, the IL-based systems showed better extraction ability and selectivity than those showed by the conventional organic solvent extraction systems(Nakashima et al., 2003, 2005; Hirayama et al., 2008; Fang et al., 2012). Therefore, more efficient solvent extraction processes by using ILs can be developed. In this study, we investigated solvent extraction processes in which ILs are employed and discuss the possibility of using ILs in the separation and recovery of rare-earth metals from electronic waste."

Jan 1, 2012

By Guojun Wang, Zejun Chen, Wenchang Liu

Al/Mg/Ti laminated metal composite sheet (LMCS) can combine the merits of each of metal components, and obtain excellent performances. It incorporates the advantages of high strength, light weight, easy melt and atomization, and good space adaptability to substitute for the bumper Al sheet of Whipple shield structure for space debris shield. The Al/Mg/Ti LMCS was fabricated by hot roll bonding technology in a certain sequence. The manufacturing process and parameters were analyzed and studied, including the first rolling reduction, roll boding temperature and stacking structure of each metal. The microstructure of dissimilar metals and bonding interface were characterized and analyzed. The optimized manufacturing procedures and parameters were presented based on the microstructure and mechanical properties of LMCS. The research results offer some guides and references for controlling the shape of bonding interface, optimizing the annealing process, improving the mechanical properties of Al/Mg/Ti LMCS.

Jan 1, 2015

By H. M. Giegerich

"INTRODUCTIONThe Red Dog Project in Alaska is being developed by Cominco Alaska, a subsidiary of Corninco Ltd. of Canada, and the Nana Regional Corporation, one of the 12 native corporations created by the Alaska Native Claims Settlement Act of1971.The State of Alaska is also a very key part of the project through its financing of the transportation system for Red Dog. Red Dog will be the third, and largest, of Cominco's Arctic mining developments in the past thirteen years, after the Black Angel Mine in Greenland, which started up in 1973, and the Polaris Mine in the Canadian Arctic, which began production six years ago in 1982.Red Dog is one of the world's great mineral deposits, with a unique combination of large size, high-grade, and a waste-to- ore ratio less than I: I, which will make it the world's largest, and one of the lowest cost zinc producers, when at full production. The present mineral reserve is estimated to be 85 million tons , at a grade of 17.1010 zinc, 5% lead, and 2.4 ounces per ton of silver. Based on the current production forecast, this will give a mine life of almost 50 years, and the deposit is still open in two directions, although the structure is becoming thinner at depth. As well, there is a satellite zone about one mile south of the main deposit which could contain up to another 8 million tons of mineral at Red Dog grades or better. This is not presently included in the reserve due to potential processing difficulties.In relation to other zinc deposits, Red Dog is the second largest ever discovered, smaller than the original Broken Hill deposit in Australia, but larger than Cominco's own Sullivan Mine in British Columbia, which is number three. It is quite possible that, when the area is adequately explored, Red Dog will be number one."

Jan 1, 1989

By Richard R. Walker, John J. Watkins, Allen C. Amos, Matulich. Angelo

THE KIDD CREEK MINE is located within the Abitibi greenstone belt, near its west end, in an area known as the Porcupine mining camp (Fig. 5). The Abitibi belt, long known for its many major gold and base metal deposits, is the largest Archean (early Precambrian) greenstone belt within the Canadian Shield. In the Porcupine area, the greenstone belt is composed principally of Keewatin (older Archean) basic to intermediate volcanics, with subordinate felsic volcanics developed• locally. Greywacke, mainly of volcanic derivation, occurs associated with and overlying these volcanics. Timiskaming (younger Archean) sediments, principally coarse clastics, unconformably overlie the Keewatin volcanics and sediments. The reader is referred to Goodwin and Ridler (1970) •r. for a more comprehensive description of the Abitibi belt.

Jan 1, 1974