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By D. A. Trotter

"This paper traces the main advances in mine lighting from neolithic times to the 1960s. The earliest lights consisted of reeds or strips of wood soaked in grease. As man's knowledge increased, the oil lamp, the candle, kerosene, acetylene and finally electricity have allowed him to see where no natural light could penetrate. These advances in technology, however, did not come easily. Many false starts were made and great dedication was required by a few lighting pioneers to overcome the many technical difficulties that were encountered. The lighting of coal mines in particular caused unique problems, as there was the ever-present threat of methane explosions. Advances in mine lighting will continue, but these advances are only possible because men like Davy, Wolf, Marsuat and Edison paved the way.IntroductionMan's first efforts at mining consisted of merely picking rock off the surface of the earth. The sun was his only source of light. The early mines of the Neolithic age were simply vertical pits, 5 to 8 m deep. In order to follow an orebody, miners began to dig horizontally from the bottom of these pits, and as work progressed the need for additional light became apparent. With the discovery of the light-giving properties of fire, man was no longer dependent on natural light. Figure 1 gives an impression of the earliest artificial mine lighting used.Early Evidence of Mine LightingCarbonized residue from wood chips which had been inserted into rock cracks can be found in early Neolithic workings. The mines at Krzemionki Opatowski in Poland contain very narrow low tunnels that were lit in this fashion and were worked from 2300 to 1800 B. C. The wood had to burn downward to provide light and because wood burns poorly in this position, the chips were probably soaked in animal fat to make them burn more easily."

Jan 1, 1982

By A. Y. Smith, R. J. Allan, E. H. W. Hornbrook, R. W. Boyle, W. Dyck

"HYDROGEOCHEMICAL METHODS in the Canadian Shield can be based on analyses of the following :(1) spring waters and their precipitates;(2) stream and river waters;(3) lake and muskeg waters;( 4) ground waters from drill holes, wells, faults, etc.;(5) waters issuing from diamond drill holes, faults, shear zones, etc. into mine workings and open pits; also analyses of precipitates associated With these waters.The first four can be utilized in both reconnaissance and detailed surveys. The last is suitable only for detailed work.For hydrogeochemical methods of prospecting to be effective, the following conditions must be present. 1. Natural waters must come into contact with mineral deposits and remain in contact with them long enough for the solution of detectible amounts of ore, gangue or indicator elements. 2. Dispersion patterns must be present in the hydrologic systems in order to trace the elements back to their source. These patterns may take the form of trains (e.g., increasing amounts of elements upstream toward t he source (s), Figure 1 ) or halos (e.g., increasing amounts of elements in bodies of water toward the source (s), F igures 2 and 3)."

Jan 1, 1971

By C. Hudson, D. Tremblay, A. Frey

"A discussion of the design, challenges and successes associated with the commissioning of the gravity recovery circuit at Canada’s newest open pit gold mine - Atlantic Gold’s Moose River Consolidated Project in Nova Scotia, Canada is presented. An overview of the project, its historical significance and overall flowsheet is provided with special focus given to the design and selection of the gravity circuit equipment including the scalping screen, gravity concentrators and the novel intensive leaching technology selected for the project. The performance of the gravity circuit is benchmarked against the feasibility study process design specifications and the outcomes are discussed. Challenges encountered during commissioning are also presented, including the use of third-party automation and the effects of screen sizing on overall gravity circuit performance. Mechanical modifications made to the Sepro Leach Reactor for the Moose River project are also discussed. A detailed technical review of the mechanical and operational aspects of the Sepro Leach Reactor is provided with key operational data on leach times, recoveries, reagent usage, solid-liquid separation, pregnant solution quality and its influence on bullion purity.INTRODUCTION Atlantic Gold Corporation’s Moose River Touquoy Mill in Nova Scotia, Canada was commissioned in the fourth quarter of 2017 with commercial production declared in March of 2018. The 2 Mtpa process plant uses a conventional, gravity-CIL process. This site was previously mined in the 1870s. Interest waned in the early 1900s but resumed in the 1930s and the mine was brought back into production in 1935 until an underground mine collapse in 1936. This mining district became famous after CRBC radio commenced a ground breaking, around the clock, broadcast of the rescue operations. Over 100 million people listened to the broadcast from Canada, the United States and the United Kingdom. These broadcasts changed radio, transforming it from a medium for music to on the spot, breaking news reporting. The mill was constructed by Ausenco on a fixed price EPC contract in the historic Moose River gold mining district, 95 km north-east of Halifax by road. The mill will process ore from the adjacent Touquoy pit for the first 5+ years of operation; after the Touquoy reserves are exhausted, the mill will process ore trucked 37 km from the Beaver Dam deposit for an additional 5 years."

Jan 1, 2019

By Seher Ata

"Virtual reality, a three-dimensional computer generated environment, has become recognized delivery system for many forms of education. This article describes the application of virtual reality to mineral processing education. An interactive mineral processing visualisation module has been developed at University of New South Wales (UNSW), Australia. The module provides students with an overview of a base metal concentrator, details about each stage of the process, as well as revealing how the mined ore progresses from stage to stage. The module also involves developing a number of instructional based plant layouts and flowsheets in the virtual environment that are intended to assist the user in understanding the essential components of the base metal concentrator.INTRODUCTIONVirtual Reality (VR) is the creation of an artificial environment that is experienced through sights and sounds provided by a computer (Squelch, 2001). The simulated environment is achieved through a host of technologies such as three-dimensional graphics, audio feedback and special peripheral devices to produce interactive environments.VR has been used in diverse fields including medicine (Riener & Harders, 2012), entertainment (Hsu, 2011), military (Manojlovich, Prasithsangaree, Hughes, Chen, & Lewis, 2003), manufacturing (Zimmermann, 2008; Jiang, 2011), and chemical processing (Schofield, Lester, & Wilson 2005; Squires, Andersen, Reklaitis, Jayakumar, & Carmichael, 2014). VR is also becoming recognized delivery system for many forms of education, including engineering education (Bell & Fogler, 1996; Bell & Scott, 1998; Shin, 2002). For example, virtual laboratories have been designed and developed to teach students fundemental features of the heterogeneous catalytic mechanisms and absorption columns (Bell & Fogler, 1995), the multi-phase and multi-component blast furnace iron making process (Babich & Senk, 2009) and to guide students to identify various safety measures while working in real laboratory (Bell & Fogler, 1996)."

Jan 1, 2016

By R. A. Crouse

The Tanco pegmatite at Bernie Lake, in the Lac du Bonnet mining district of southeastern Manitoba, is a unique deposit of Li, Rb, Cs and Ta, with substantial reserves of Be and several industrial minerals. This paper summarizes the present state of understanding the regional geology, structural setting, zoning, mineralogy and geochemistry of the pegmatite, and the mining and ore-processing methods used in its exploitation.

Jan 1, 1979

By J. Armitage, J. Erskine

Feed level and thickness measurements are essential in the optimization of an electric arc furnace. A precise measurement of the feed thickness and level gives operators the ability to increase the smelter efficiency and reduce the maintenance cost. Hatch has developed a radar system which is an affordable, low maintenance, and accurate level measurement system. The radar units can be installed across the furnace to measure the feed level and the feed thickness can be calculated with one slag level sounding. The present paper describes the development of radar systems as a process optimizing tool by furnace controls. The authors will discuss the challenges involved in installing eight radar units on the roof of a six-in-line electric furnace.

Jan 1, 2015

By Hyung Sup Choi

The preparation of high-purity zirconyl compounds was studied in order to develop an economical process for obtaining pure zirconium via the caustic fritting of zircon sand. The direct dissolution of caustic frits with concentrated hydrochloric or nitric acid at 80c. followed by the addition of a small amount of acidified gelatin, gave high-purity zirconyl chloride or nitrate. The addition of a small amount of gelatin caused a mutual flocculation between colloidal silica and gelatin. The precipitation of this silica floc markedly lowered the content of silica in the product. The silica content of the compounds (or solution) so produced, generally less than 100 ppm., was sufficiently low for tributyl phosphate extraction for nitrate solutions. It was found that the degree of purification de-pends not only on the procedures employed but also on the nature of the frit itself. Silica was more effectively eliminated from the fritted product produced at higher temperatures, and less silica was present in the com-pound prepared from the frit produced in a shorter heating time. In order to ascertain the nature of the

Jan 1, 1965

By Jaeheon Lee, Junmo Ahn, Isabel F. Barton

"Newmont’s Mike prospect, currently undeveloped, is a blind Cu-Au(-Zn) deposit on the Carlin Trend, containing >8.5 M oz. Au, 1027 M lbs. Cu, and 809 M lbs. Zn as Carlin-type gold and polymetallic Cu-Zn minerals in Paleozoic lower-plate carbonates and shales. This project was undertaken 1) to examine the effectiveness of different lixiviants for leaching the Mike supergene Cu-Au ores via bottle roll tests, and 2) to determine what ore minerals resist dissolution in each leaching agent by comparing the mineralogy and chemistry of head and tail samples. Sulfuric and sulfurous acids were used to leach copper and cyanide was used to leach gold. Thiourea, glycine, and other lixiviants were used to leach both base metals and precious metal. QEMSCAN and SEM study of six samples of different ore types and grades indicate that the Au occurs as varieties of native gold, including auricupride and electrum. Major Cu minerals are native Cu, cuprite, malachite, chrysocolla, and conichalcite (Ca-Cu arsenate), with locally significant Cu in jarosite and goethite. Gangue mineralogy is dominated by quartz, sericite, chlorite, alunite, smectite and kaolinite, K-feldspar, and iron oxides (sensu lato). Results of bottle roll tests and leach residue mineralogy will be presented and discussed at the conference.INTRODUCTION Resource and Geologic Setting The Mike deposit is a large, blind Cu-Au(-Zn) deposit in the Maggie Creek district of the Carlin Trend of Nevada, USA, near the Gold Quarry mine (Figure 1). The mineral inventory, based on drilling, is 8.568 Moz. Au, 1027 M lbs. Cu, and 809 M lbs. Zn at average grades of 0.72 g/t Au, 0.34 wt% Cu, and 2.13 wt% Zn (inventory for a cone at $400/oz Au and $0.80/lb Cu by Norby and Orobona, 2002)."

Jan 1, 2017

By G. W. Poling, G. W. Hawthorn

"""Unassayable gold and platinum group metals"" have come into vogue in the 70sand 80s in certain jurisdictions as a means of perpetrating fraud. Usual arguments are that a particular ore is not amenable to ""conventional fire assaying"". Explanations for unassayable gold usually revolve around: evaporation of micron-size gold; vaporization of organic gold complexes; volatization of gold halides; alloying of gold with PGM's which prevents fusion or alloying which prevents collection .This paper reviews several of the myths and truths of gold and PGM assaying with the knowledge that not a single mine operatesin thefree world producing gold from unassayable ore.INTRODUCTIONAccurate analyses of exploration data and estimation of ore reserves are two of the most important functions of professional geologists and engineers in mine development. The problems encountered become particularly acute when dealing with precious metal values where very low grade deposits (in the range of 0.0 I Troy oz per ton or - 0.2 ppm (g/t) by weight) sometimes are economic or constitute ""ore"". To emphasize this ""scarcity effect"", a gold assay of 0.4 g/t (0.01 T oz/st) would result from the presence of a single 420 J.tm (35 mesh) gold flake (which weighs I milligram) in a 5 kilogram siliceous sample.The current high gold price and the prospects of high profit margins awaiting exploitation of even very low grade gold deposits, has spawned a sizeable group of incompetent or fraudulent gold assayers. These ""assayers"" will often report significant precious metal values where no such values occur. Failures of legitimate assay labs to confirm these ""significant"" assays are often attributed, by the charlatan, to their capability of detecting ""unassayable gold"" while the check assayer cannot. Geologists and engineers lacking detailed knowledge of sampling and assaying techniques are often hard-pressed to convince a gold-fever aroused company executive or investor-client to abandon a property on which attention-grabbling values have been reported, often by more than one laboratory. Professionals engaged in such evaluations must acquire an understanding of contemporary precious metal sampling and assaying techniques . Only then can they determine whether misrepresentation of values have been perpetrated"

Jan 1, 1989

By T. E. Smith

"This paper describes the application of a motor-driven flywheel unit, known as a peak shaver, to compensate for the cyclic load fluctuations of a large electric dragline installed at Pine Point Mines, near Great Slave Lake in the Northwest Territories. Of particular interest in this application is the fact that the power system supplying the dragline is a relatively small isolated system, with the major generating source approximately 170 miles from the mine.The cyclic load fluctuations of the dragline are theoretically capable of producing a maximum swing of up to 11 megawatts, which approaches nearly 50% of the installed generating capacity. To reduce these load fluctuations to acceptable limits various alternatives were considered, leading to a decision to install a peak shaver to optimize the operations of both the mine and the power system. Without the peak shaver, the dragline operations would be severely curtailed and additional diesel generation would have to be run at considerable expense, otherwise the power system frequency fluctuations would be totally unacceptable. With the peak shaver, power and frequency fluctuations are kept within tolerable limits, and optimum economic operation of the diesel generation is obtained.The paper outlines the steps leading to the selection of the peak shaver as the compensating device, describes the equipment installed and gives details of operating experience with the dragline/peak shaver combination since installation early in 1979. This .peak shaver is the first of its kind in North America, the only other peak shaver installation being in Australia.IntroductionPine Point Mines Limited owns zinc-lead mining and milling operations located at Pine Point, Northwest Territories, 5 miles south of Great Slave Lake (Fig. I). The company is staffed and managed by Cominco Ltd., which has a 69% interest in Pine Point Mines.Mining activity in the Pine Point area was first recorded in 1898, when the Yukon gold rush was on, but when the zinc/lead showings in the Pine Point area did not yield much in the way of gold, interest in the area soon waned. Cominco Ltd. first acquired some claims in the Pine Point area in 1928, but interest was sporadic until the early 1950s, when extensive exploration indicated rich pockets of zinc/lead ore near the surface. Pine Point Mines Limited was formed in 1951, with Cominco acquiring a majority interest in the company."

Jan 1, 1980

By G. Capobianco

"The coal industry is an important part of Canada's economy - as an energy source, employer, and generator of export earnings. Coal comprises 71% of our fossil energy and with rapidly advancing handling and burning technology will clearly play a major role in our national energy mix, eventually as synthetic gases and liquids.International coal markets are very competitive and Canada is disadvantaged by long rail hauls to port, and a heavy tax burden. However, high mine productivity has allowed us to increase our markets.Currently, domestic markets are dominated by coal use for electrical generation, a market with significant growth opportunities.Strong growth is expected in export thermal markets, while metallurgical coal demand is projected to show little or no growth in the medium term. IntroductionThe coal industry is a vital part of the Canadian energy scene .• Coal supplies 17% of Canada's energy.• On a per capita basis, Albertans use more energy in the form of coal than they do oil and gas.• The value of Canada's exports of coal last year was equal in value to all the cars we imported from Japan.• Coal is our largest single export to our seco nd largest trading partner, Japan.• The value of coal produced in Canada exceeds the value of any other single mineral produced in thi s country.• In Alberta, the safety record for coal mines is on a par with that of department store clerks.• The coal industry employs about 25% of the total number of people employed in all metal mines in Canada, directly and indirectly accounting for about 50 000 jobs.Coal comprises 71% of Canada' s hydrocarbon energy resources on a crude oil equivalent basis . This is more than double our oil sands resource and dwarfs our conventional crude oil and gas resources (Fig. I). In the short term, coal as a solid fuel plays a significant part in the Canadian energy scene. In the longer term, coal, in the form of electricity and eventually liquids and gases, has a tremendous role to play. In 1986, Canada produced 57.8 million tonnes, slightly down from the record high of 60.8 million tonnes in 1985. Our exports in 1986 were 26.0 million tonnes, a growth of 53% in three years."

Jan 1, 1988

By W. S. Fyfe

Gold is mobilized and precipitated in a wide variety of environments ranging from those of weathering and biological phenomena, to pluton emplacement to deep metamorph ism . But it appear that pervas ive leaching of large rock volumes fo llowed by the focussed di charge of typically low salin ity flu ids is frequently involved. There are great gaps in our knowledge, particula rly with re pect to gold in very high temperature fl uids generated at near Moho depths. But uch flu id may play an important part in Archaean pluton associated lode gold deposits whe re ultra high temperature fluids, rich in C02-CO-COS, may be associated with magma underplating and crustal assi mil ation processes (sag subduction) associated with very den e ult ramafic magma . Other environment with great potential include those of major thru t fau lt and strike slip fa ult s where large quant ities of fluids are mobilized .

Jan 1, 1986

By M. Abumiya, N. Onodera

Stabilization of arsenic via the precipitation of large-sized scorodite (FeAsO4·2H2O) particles usually involves the use of expensive autoclave systems operated under high temperature and pressure conditions. Alternatively, DOWA developed a novel scorodite synthesis process (DMSP®) wherein the Fe(II) ions in solution containing As(V) ions were oxidized by O2 gas under atmospheric pressure. In this process, crystalline scorodite particles were formed via the formation of a gel-like precursor containing Fe(II). Based on this concept, in this study, we have demonstrated the synthesis of scorodite particles by the addition of Fe(III)-containing solution to the experimental solution containing Fe(II) and As(V) ions, without the O2 gas oxidation process. Ferric sulfate (Fe2(SO4)3) was used as the source of Fe(III) ions. Results indicate the precipitation of scorodite particles, comparable to that of the O2 gas oxidation method.

Jan 1, 2014

By F. M. Doyle, G. Sidhu, A. J. Dussault, A. Raygani

There is a growing demand for rare earth metals for use in high strength permanent magnets, most notably Nd2Fe14B. Rare earth metals are extremely reactive, with reduction potentials around -2.5V SHE, and are conventionally produced by molten salt electrolysis. The current work was done to investigate an earlier report of electrodeposition of a neodymium ferroalloy from aqueous solution, to determine whether this approach could be an environmentally and economically competitive commercial approach for producing feedstock for permanent magnets. Such a process would be analogous thermodynamically to the Castner- Kellner process, in which aqueous sodium chloride brine is electrolyzed in cells with mercury cathodes. Metallic sodium forms an alloy (amalgam) at the cathode, thereby lowering the activity of the metallic sodium significantly below unity and making the reduction potential of sodium significantly less negative than the standard reduction potential. Here we report the effects of Nd/Fe ratio in the electrolyte, current density, temperature and two different complexing agents, glycine and cysteine, on the composition and morphology of the electrodeposits, along with current efficiency. The energy needed to produce neodymium as Nd:Fe alloys by aqueous electrodeposition was compared with values estimated for production by molten salt electrolysis and the thermodynamic energy requirement.

Jan 1, 2014

"The Code was developed in 2004 through the Collaboration Agreement between Institution of Mining Engineers of Chile (IIMCh) and the Ministry of Mining (Chile) in Dec 2002. It is an amalgamation of current practices with respect to standards and procedures for exploration prospects, mineral resources, and reserves for the purpose of public reporting. Certification is required to prepare and issue information on mineral assets according to the guidelines that regulate the technical, economic, and environmental aspects that satisfy the conditions set by the Chilean capital and financial markets.The Mineral Resources Committee of the Instititution of Mining Engineers of Chile (IIMCh) is pleased to introduce theCode for the Certification of Exploration Prospects, Mineral Resources and Reserves which is the result of a Collaboration Agreement between the IIMCh and the Ministry of Mining established in December, 2002.This code synthetizes the present practice of the mining industry in regard to standards and procedures applied to exploration prospects, mineral resources, and reserves with the purpose of reporting publicly on financial instruments based on these mine assets in the capital markets. These standards follow general criteria already adopted and applied by capital markets in those countries characterized by a very dynamic and well developed mining sector such as Australia, Canada, Southafrica, United Kingdom, and others. The work done by the Mineral Resources Committee of the IIMCh has had the recognition of the Combined Reserves International Reporting Standards Committee (CRIRSCO) that leads the establishement of an international code in these matters. CRIRISCO is an entity formed by representatives of the countries previously mentioned, a representative of the Society of Mining Engineers of the UStates and a representative of the IIMCh. The Institution thanks the Ministry of Mining, the representatives of these Ministry in the Mineral Resources Committee, and specially the Minister of Mining, Sr. Alfonso Dulanto Rencoret due to the genuine support given to the IIMCh in the preparation of this Code.The Institution also thanks the Superintendencia de Valores y Seguros (SVS) because of the help given continuously to the Committee as well as by the interchange of opinions and suggestions received during the preparation of this document."

Jan 1, 2003

By J. Walker, G. E. Kim

Since May of 2000, Mogas Industries, in partnership with F.W. Gartner Thermal Spraying Co. and using the services of Perpetual Technologies, has invested time, energy, and resources towards developing novel ball valves for high-pressure acid-leach (HPAL) service. In addition to developing new valve designs, an aggressive coatings development effort has been undertaken to improve the protective quality of the coatings so as to enhance the performance and extend the life of valves in severe HPAL conditions. In 2001, Mogas Industries qualified and applied a nanostructured titanium oxide (n-TiO2) coating for gold and nickel/cobalt HPAL services. The n-TiO2 coating provided dramatically superior protection against abrasive and erosive wear, fared very well against high-pressure autoclave corrosion testing, and has performed well in HPAL service.

Jan 1, 2004

By Charles Kingsley

THE PRESIDENT (DR. C. B. KINGSTON, member C.l.M.M.) expressed regret that neither of the authors of the paper was able to be present to submit the paper in person. In their absence, it would be introduced formally from the Chair. It was a clear, straightforward account of a fine piece of shaft sinking, cleverly conceived and boldly executed. He referred briefly to the distribution and nature of the Dome ore-bodies and stated that, for both the miner and the metallurgist, the mine had provided a wide range of problems of unusual interest. Discussion on the paper was then invited. MR. THOMAS PRYOR said the paper was most opportune, because the subject of internal shafts did not appear to be fully treated in current mining literature. Many members were not familiar with Canadian gold deposits and it would be of interest if the authors could give a brief description of the location of the ere deposits of the Dome mine. This information would doubtless explain why a new internal shaft was needed in a position which required such an exceptionally long cross-cut to connect it to the main hoisting shaft to surface. It would also add to the value of the paper if the authors would give some idea of the duty expected of the new shaft in terms of tons of rock hoisted and of trips engaged in the transport of men and materials, and it would be helpful if figures could be given of the total capital cost of the hoists and subsidiary excavations at the shaft top, and of the cost per foot for sinking and lining the shaft below the collar. Turning to details of the paper, one was favourably impressed by the care given to the provision of a good travelling way for men in the main cross-cut, as shown in Figure 1. It was by no means always that one could walk in comfort and safety in a working where there was a 20-in. ventilating pipe in the roof.

Jan 1, 1939

During the past 10 years, research work to improve the survey of stope limits after mining supplied useful information, particularly for large open and sub-level stopes, regarding waste dilution caused by differences between final production limits and planned stope limits. However, the efficiency of this information to improve the overall efficiency of the mining process is limited, given that the impacts of inaccurate ore limits leading to dilution (sensu stricto) and ore losses haw not been considered adequately. Geological/sampling information should be optimized in terms of quantity and/or quality for the deposit characteristics and the constraints of the mining method used. As industry practice regarding the definition and recording of dilution is flexible and as ore losses frequently am poorly doc-umented, the use of these terms is reviewed. Simulations were carried out on two typical narrow gold deposits, based on an earlier study at Inco's Thompson mine regarding the impacts of wide to narrow delineation grids using recorded variations of vein geometry. Vertical to sub-vertical deposits of 3 m and 6 m widths mined by long-hole open stopes were considered. Deposits delineated by 7.5 m (25 ft) grids were taken as a base case and the impacts of less accurate limits in conjunction with long hole mining based only on a 15 m (50 ft) delin¬eation grid. The impacts of overestimation (dilution) and underestimation (metal losses) were considered separately, using the average error of +/-0.62 m recorded in the Inco study. The impact of less accurate information was much stronger on the narrower deposit: both dilution and ore losses diminished the net present value of the 3 m wide deposit by 39.27% and 45.41%, respectively, and that of the 6 m wide deposit by 12.84% and 11.55%. As the impacts of ore loss and those of dilution on the net present value am almost identical in these simulations, we could, in practice, assume a 50/50 split between dilution and ore losses in such a case. These results do no take into account the effects of local optimization measures taken at the mine production level (blasthole sampling near stope limits, etc.) The potential impacts of geological and sampling uncertainties in terms of lower NPV justify and require more systematic efforts to ensure that deposit appraisal work and feasibility studies are adequate to optimize company revenue and competitive returns to investors from mine production activities.

Jan 1, 2005

By M. Boher, J. Lehmann, M. C. Kaerlé

"In the production of high quality steel, the understanding of the interactions between liquid steel and refractories and of their effect on steel purity and cleanness are becoming more and more important.An experimental study has been per-formed in order to estimate the importance of the reaction between a MgO-based tundish refractory and an Al-killed steel. The results show a pollution of the liquid steel:•the silicon content of the liquid steel increases due to the reduction of the silica of the refractory by the aluminum contained in the steel; and•a reoxidation of the steel occurs and the formation of an oxide layer on the refracto-ry, mainly composed of spinel crystals and of Ca-aluminates is observed.The transfer mechanisms of the various elements are analyzed."

Jan 1, 1997

By R. L. Alexander

"Madawaska Mines Limited, incorporated in 1975 is the successor to Faraday Uranium Mines Limited. The history of the latter's mine development and corporate changes are outlined. This paper describes the geology of the Bancroft area and the rock types found in the mine, particularly the pegmatite which is the host rock for the uranium. The structure, mineralogy and distribution of the ore shoots are described with the method of grade control and mine development. The paper concludes with a summary of the production and mineral reserves.Location, Access, and PropertyMadawaska Mines Limited is located in Faraday Township, Hastings County, Ontario. The mine is in the N.T.S. quadrant 31 F/ 4, Bancroft sheet and near 46 degrees 01 minute latitude, 77 degrees 46 minutes longitude. The mine is one-half mile north of Highway 28, five miles (8 km) west of Bancroft, and is accessible by various highways from Toronto, Ottawa, Peterborough, and Belleville. (Fig. 1). A landing strip for small aircraft is located at the northwestern edge of Bancroft. Bancroft is a modern community with a population of 2,400. The company has the mineral rights to 2982 acres (1207 hectares) surrounding the mine workings and plant which are situated in the north parts of Lots 16 and 17, Concession XI, Faraday Township."

Jan 1, 1986