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By Sunil S. Gandhi

"The Mountain Lake deposit is a tabular sandstone-type uranium deposit, hosted by the basal unit of Middle Proterozoic Dismal Lakes Group. Uranium occurs mainly as sooty pitchblende disseminated in stratiform lenses within gently dipping quartzose sandstone. It is associated with copper sulphides, pyrite, hematite, and traces of nickel and cobalt arsenides and of silver.Exploration HistoryUranium showings on the PEC claim group were discovered during 1969 by an airborne radiometric survey carried out over the Dismal Lakes-Great Bear Lake area by Aquitaine of Canada Limited (Bizard and Salat, 1969). Some drilling was done in the vicinity of the showings in 1975 by the company under a joint venture with Eldorado Nuclear Limited but the results were not encouraging (Hassard and Woollett, 1975). During 1972, Trigg, Woollett and Associates Limited conducting surveys for Imperial Oil Limited, discovered numerous high-grade radioactive boulders scattered over a distance of several kilometres north and west of the showings, and the area north of the PEC claims was staked as the YUK claims (Ahuja, 1974). A systematic study of the boulder distribution and Pleistocene geology suggested a source additional to the showings. More intensive exploration followed, and in 1976 drilling just north of the PEC claim group boundary intersected the main deposit at a depth of 75 m to 150 m, beneath overburden up to 60 m thick. Part of the deposit extends into the PEC claim group which is under exploration by the Aquitaine-Cominco Joint Venture.The following brief description is based on the presentations in 1978 by F. Hassard of Trigg, Woollett and Associates Limited at the Geoscience Forum in Yellowknife, and by S.S. Gandhi of the Geological Survey of Canada at the Mineralogical Association of Canada Uranium Short Course in Toronto."

Jan 1, 1986

"THE GOLD MINING REGION of Timmins - Val d'Or, astride the Ontario-Quebec border, has long suffered the effects of rising costs during the period when the U.S. price of gold was fixed at $35 per ounce. The federal government, through such assistance programs as that set up under the Emergency Gold Mining Assistance Act (E.G.M.A. ) in 1948, has subsidized the gold mining communities of Canada for a total of over $300 million to March 31, 1972. Of this, the Timmins - Val d'Or ""gold belt"" has received more than twothirds, almost $220 million. In spite of these continuous subsidies, only 12 gold mines are still producing in the Timmins - Val d'Or belt, whereas 71 mines have received subsidies for some period since 1948. The vital question is how the communities previously supported principally by the mining of gold will survive in the long run, as many of the older mines either are already depleted or are quickly becoming so. With the rising price of gold on the 'free market in recent months, prospects look a little brighter for the time being. Even with the increased official price of U.S. $38, which made the maximum government subsidized price about $48 per ounce, gold mines have not sold any gold to the government since January 1972 and some stopped doing so months before that. The populace of the region has not been enthusiastic about relocation nor about extensive retraining programs in the past and probably will not be in the future. So, when the remaining gold mines become depleted, the old problems of community depression will remain."

Jan 1, 1973

By K. D. A. Whaley

Abstract -The Captain North Extension deposit consists of five sulfide lenses hosted in cherty and chloritic metasediment that is bounded by quartz-eye rhyolite and laminated rhyolite . Lens 2 consists of sphalerite and galena with silver-rich tetrahedrite in chert. Lens 3 contains massive pyrite, with chalcopyrite and minor gold, gradational to minor pyrite in a chloritic metasediment . The other lenses are unexplored. The sulfides occur as beds, fracture infills, and disseminated grains. Reserves are estimated at 207 555 tonnes grading 7.38% Zn, 2.76% Pb, and 91.81 g/t Ag. The deposit is isoclinally folded, dips steeply west, plunges 50 degrees south, and is faulted out to the north, where drag folding has reversed the plunge. Minor cross-faults contain talc and sericite. High sphalerite but low pyrite abundances result in poor responses to standard electromagnetic techniques. Lens 3, which contains more pyrite than Lens 2, responds better to induced polarization and allows detection. Geochemical anomalies are found in a nearby swamp and stream, but an impervious till cover inhibits the development of soil anomalies.

Jan 1, 1992

By P. H. Willis

Since the 14th CMMI conference, held in Edinburgh in 1990, at which a paper was presented by the author (Willis, 1990) reviewing the role of integrating new technology as a survival strategy for South African gold mines, considerable change has occurred in the South African mining industry. This paper reviews the current state of the industry and provides an update on the technologies discussed ten years ago. It reviews available technology and provides a broad economic assessment of these technologies if they were to be introduced in an integrated mining system with a focus on deep level mining below 3000 m. It also reviews possible future technologies currently being researched and developed by CSIR: Division of Mining Technology (Miningtek).

Jan 1, 2000

By G. W. H. Norman

"The La Corne molybdenite-bearing veins, discovered in 1915, lie halfway between Amos and Val d'Or near the southwest corner of La Corne township, Abitibi county, Quebec. The Molybdenite Reduction Company, which carried on operations during 1927 to 1930, sank a 200-foot inclined shaft to develop the property and produced about 22 tons of concentrntes from a 30-ton mill during 1929. Hollinger Consolidated Gold Mines, Limited, carried on further underground exploration in 1930. The Molybdenite Corporation of Canada drilled a part of the property in 1938 to 1939 and produced 1 ton of concentrates in 1938. Wartime Metals operated the property from 1942 to July 15, 1945. At this time the mill was enlarged to treat 200 tons daily. Molybdenite Corporation of Canada since July 15th, 1945, have continued the operation of this property and have revised the mill flow-sheet in order to produce both a bismuth and a molybdenite concentrate.The production for the period 1942-1946 is as follows:Total molybdenite production from the mine in the 1942 to 1946 period was about 4,127,400 lb.The La Corne deposit occurs at the northwest contact of a small mass of biotite granite with biotite schist. The form and extent of the biotite granite mass is concealed by a wide sand plain that extends northwest and west from the deposit and overlies bed-rock except in four small outcrop areas. These are spaced 1,000 and 2,000 feet apart along a narrow strip extending 5,000 feet south from the mine. The outcrops suggest that the granite must be at least 1,500 feet wide and 3,000 feet long northeastward. Where exposed in the mine workings the contact dips 70°N.W., but is not a sharply defineable feature due to the presence of numerous granite dykes and tongues in a zone of biotite schist 100 feet wide along the margin of the granite. The biotite schist in the few outcrops that flank the north and south sides of the granite strikes northeast and dips 60° to 70° S.E."

Jan 1, 1954

By Stuart J. Schofield

Introduction The study of the ore deposits of British Columbia is one of fascinating interest not only from a scientific but also from a commercial standpoint and certain wide problems in connection therewith have interested me for some years. Several of these problems have been set forth in papers presented before this Institute on previous occasions. In 1918 it was pointed out that the commercial ore deposits of British Columbia, with one exception, were associated with the granodiorite batholiths of upper Jurassic age. This was followed, in 1922, by a discussion of the ore deposits of British Columbia in which the mineral belts of the province were defined and named, showing a zonal arrangement of ores in which the Pacific coast deposits are characterized by the presence of copper, while the interior belt is marked by the presence of silver, lead, and gold. Methods Of Investigation In reading various reports on the economic geology of British Columbia one is struck with the fact that the mineral veins may be arranged as a system and further examination will show that such a system follows two main directions, one northeasterly and the other northwesterly, both related in origin to the same force.

Jan 1, 1925

By Ernest Becker

Golder Associates provided overall radiological direction and assistance to the client in their interactions with the Canadian Nuclear Safety Commission and operational radiation protection services for the remediation of a calciner that had been used to process uranium. The project was somewhat unusual in that the radioactivity from within the calciner room was removed from the site and the cleaned steel recycled. The presence of yellowcake within the process equipment required stringent radiation protection measures. This project was completed successfully with minimal radiation exposures to the workers and the effective protection of the environment.

Aug 1, 2010

By Sepulvedam Jaime E., Levi Guzmán Rivera

"Grinding media consumption rates and their dependence on key operating conditions in semiautogenous grinding mills is analyzed on the basis of a detailed mathematical model recently developed by Moly-Cop´s specialists which describes and takes into account the three primary media consumption mechanisms, namely: abrasion/corrosion, surface spalling and impact ball breakage. The influence of key mill operating conditions – such as ball filling, discharge grate opening, mill speed, lifter profile, and ball quality – on their corresponding grinding media consumption rates is explored via a variety of model simulations, discussing in every case the independent contribution of each of the indicated consumption mechanisms to the estimated total ball consumption rate.INTRODUCTIONA thorough understanding of the independent contribution of each grinding media wear mechanism is extremely important, especially in semi-autogenous grinding (SAG) operations where macrowear (spalling) and ball breakage cannot be ignored or neglected. The high impact conditions imposed in modern SAG milling environments has created serious challenges for grinding media manufacturers since their products must be able to perform with minimal breakage and surface spalling.GRINDING MEDIA WEAR MECHANISMFor SAG milling operations, at least 3 different mechanisms have been identified as the main contributors to the observed overall grinding media consumption, here referred to as: abrasion / corrosion, ball breakage and surface spalling.Wear by Abrasion/CorrosionThe abrasive/corrosive wear mechanism has been discussed in depth in previous publications (Benavente Hector, 2007; Guzman Levi, 2014; Sepulveda and Morrow, 2014). The most widely accepted approach to mathematically characterize the consumption (wear) kinetics of grinding media in rotary tumbling mills is known as the Linear Wear Theory (Prentice, 1943; Norquist, 1950; Sepulveda, 2004) which claims that—at each instant 't' after a grinding body enters the mill load—the rate at which the body loses weight is directly proportional to its surface area exposed."

Jan 1, 2016

By John F. Gartner

"Traditionally, the geologists of Canada have been occupied with the tasks of finding new mineral bodies, locating gas and oil fields or hunting for economic deposits of industrial minerals. A very minor percentage of graduate geologists have applied their skills to solution of the ""urban blight"" or employing their understanding of ""Nature"" for the optimum use of land by mankind. However, things are changing quickly. The role of the geologist in the planning process is being established. It is an exciting time! Geologists are now being consulted on a wide range of urban planning problems. These vary, tor example, from assessment of the geological environment for the new communities of Erin Mills and Meadowvale, which will have total populations in excess of 100,000 people (truly a satellite city), to a complete geological/ geohydrological assessment of the new sanitary landfill for the city of Guelph.Use of geologic techniques and methods for urban studies must be enhanced with certain skills not taught, in the past, to the geologist. These include airphoto interpretation, soil mechanics, geohydrology, municipal engineering and highway engineering to mention a few. The geologist has the unique training to assess the natural environment and to discover, warn and explain the implications of man's attempt to command his environment."

Jan 1, 1972

By M. Tanaka, H. Narita, K. Morisaku

"The selective separation of palladium (Pd), platinum (Pt), and rhodium (Rh) from a hydrochloric acid solution by solvent extraction was investigated using amide-type extractants, i.e., N,N,N’,N’-tetra-n-octyl-thiodiglycolamide (TDGA) and N-n-hexyl-bis(N-methyl-N-n-octyl-ethylamide) amine (BisAA). The separation experiments employed two separation schemes: (1) extraction of Pd with TDGA and that of Rh and Pt with BisAA; and (2) extraction of Rh, Pd, and Pt with BisAA. Separation scheme 1 achieved the highly selective separation of each metal. For separation scheme 2, Rh can be recovered prior to Pd and Pt, despite having a lower selectivity for Pd/Pt than separation scheme 1. INTRODUCTIONThe recent increase in the use of platinum group metals (PGMs) in industry (especially auto catalysts containing palladium (Pd), platinum (Pt), and rhodium (Rh)) has lead to their increasing waste; therefore, improvements in the recovery techniques for PGM have received significant attention. In metal refineries, PGMs are mainly separated and purified by solvent extraction (Cox, 2004). The extraction process used in INCO’s Acton precious metal refinery is one of the most famous commercial processes and is utilized worldwide. In this process, silver is first removed as a residue (AgCl), and then gold, Pd and Pt are extracted from hydrochloric acid (HCl) solutions using dibutylcarbitol (DBC), dialkylsulfide (DAS), and tri-n-butylphosphate (TBP), respectively. Finally, Rh remains in the raffinate (Barns & Edwards, 1982).The development of a successful solvent extraction process depends on the choice of the appropriate extractants. We have studied the extraction of PGM using N,N-disubstituted amide compounds (Narita, Tanaka, Morisaku, & Abe, 2004; Narita, Tanaka, Morisaku, & Tamura, 2006; Narita, Tanaka, & Morisaku, 2008a, 2008b). They are relatively stable against acids, and their metal extractability can be improved by changing the side chain length and/or introducing additional donor atoms like sulfur and nitrogen. We have recently found that thiodiglycolamide and an amide-containing tertiary amine have good extractabilities for Pd and Rh, respectively."

Jan 1, 2012

By K. Adham

Iron chloride pyrohydrolysis (ICP) is used as an efficient way to fix iron as an oxide, for sale as a by-product or for safe disposal. Iron chloride is reacted with water at elevated temperatures to yield iron oxide and hydrogen chloride. Both the steel industry and synthetic rutile producers make extensive use of ICP. Two technologies are available for ICP: fluidized bed (FB) and spray roaster (SR). Both technologies are energy intensive. Here, fluid beds and spray roasters are compared with respect to their fuel and electrical energy consumptions. Roaster size and oxide product characteristics are also considered. Process models are prepared, using the METSIM® software, and specific energy consumptions are compared. The results will help the industry decide which technology best suits its goals and at what energy cost.

Jan 1, 2006

By D. Mills, W. J. Brantina

"Mechanical and magnetic characteristics of ferromagnetic materials were investigated by a pulsed ultra-sonic technique. Two instruments, the Ultrasonic Attenuation Comparator (Sperry) and the standard type Reflectoscope (Sperry) were used for measurements of the attenuation of the ultrasonic pulse. The effects of elastic tensile and compressive stresses on the attenuation of annealed and cold worked material are described. In addition, the effects of plastic de-formation, relaxation and aging processes and different ultrasonic test frequencies are reported. The results for Armco iron, SAE 1020 steel, SAE 4340 steel and AISI 420 stainless steel are shown. Under the test conditions, the attenuation was found to be largely a sum of two components; a ""dislocation"" component associated with the losses accompanying the oscillations of dislocation line segments and a ""ferromagnetic"" component associated with the microeddy currents generated by magnetic domain wall oscillations. Either of these components might be dominant depending on the nature of the particular specimen and the test conditions. Finally, the possibilities of using ultrasonics in residual stress determinations, in fatigue studies and in the study of the ductile-brittle transition in ferrous materials, are briefly discussed."

Jan 1, 1960

By H. Clare Horwood

"In the Red Lake area in northwestern Ontario the relationships between general structures and structures containing ore deposits are among the most unusual and most interesting of any in the Precambrian Shield. The more important orebodies, which are in the central-eastern part of the area, occur in a variety of rocks on the northeastern, eastern, or southeastern sides of a series of granite stocks. Other deposits in the western part of the camp also are structurally associated with granite masses .The relationships were determined in the course of general and detailed geological mapping by detailed analyses of the fracture patterns in the rocks adjacent to the orebodies. In every case it was found that the structures containing the ore were produced by compressive stresses from the direction of intrusion of the granite masses( 2).The Red Lake area lies in the Patricia part of the district of Kenora and is accessible by boat from Hudson or by airplane from Kenora, Sioux Lookout, or Winnipeg. A road from Vermilion lake, on highway No. 17, was opened in August, 1947.The first discoveries of mineralization in the area that proved to be of economic importance were made in 1925 by Lorne Howey and George McNeely for Haileybury interests and by Ray Howey and W. F. Morgan for Mcintyre-Porcupine Mines, Limited. Both prospecting ventures were organized because of information presented by Bruce(l) in his map and report for the Ontario Department of Mines. The discoveries, which were both along the same structure, a quartz porphyry dyke, later developed into the Howey and Hasaga gold mines. Other discoveries were made at intervals as a result of prospecting and development work on ground staked for its location."

Jan 1, 1954

By E. S. Moore

In the townships of Genoa and Marion, Subdury Mining Division, Ontario, there is a group of twenty-three mining claims known as the Jefferson claims. They are controlled by the Jefferson Mining Corporation and they were staked in 1908 by W. E. Smith, formerly of Sudbury, Ontario, and now of Smith & Reitz, a law firm of Minneapolis, Minnesota. These claims were staked for iron ore and in 1910 about 4000 feet of diamond-drilling was done on them. During the drilling operations galena and sphalerite ~were found in the iron formation in cores from holes, Nos. 2 and 3, claim W. D. 717, Genoa township. This discovery lead to a search for galena and sphalerite in the vicinity and a streak of rock containing these minerals was found in the iron formation a short distance to the east of. the drill holes. A shaft was sunk on this outcrop in 1912 to a depth of 8 feet and bottomed in an attractive lens of galena. Stripping revealed other small exposures of galena and sphalerite in the iron formation.

Jan 1, 1926

By M. Lebeuf, A. Dumais, C. Farsangi, N. Singh

The Nunavik Nickel project began ramp-up of a new ore body (Expo) in November 2014. This new deposit is significantly more competent than the previous ore type milled (i.e., the plant moved from a feed with a BWI of 12.2 kWh/t to predominantly material with a BWI of 19.6 kWh/t). Despite circuit changes made in advance of the Expo ore ramp-up (grinding media size, mill loading/power draw, and cyclone configuration) the throughput of the plant was bottlenecked at 90% of targeted throughput with multiple stoppages to grind-out the primary mill due to excessive circulating loads. During this time, the secondary milling circuit was under-utilised: therefore the focus for debottlenecking plant production became increasing the product size of primary milling. Given the scope of changes already made to the circuit, it was decided to test the mill in open circuit. The milling changes were modelled using the Molycop Tools package to identify potential problems. In the modelling and plant trial it was apparent that the ball size in the secondary grinding circuit was inadequate, resulting in pebbling. The power draw of the secondary mill was brought up to minimize pebbling and the average ball size was increased. The switch to open circuit primary milling permitted a significant augmentation in plant tonnage. While the overall grinding efficiency decreased using the open circuit configuration, the ability to increase throughput made it the clear operating choice.

Jan 1, 2016

By D. Fredlund

The decommissioning of uranium tailings facilities often requires the design of a suitable cover system. In northern climatic environments there is a portion each year that can be considered to be ?inactive? while the remainder of the year can be considered to be ?active?. There are numerous engineering design assumptions required when analyzing both the ?active? and the ?inactive? portions of the year. Cover systems are subjected to complex boundary conditions and nonlinear unsaturated soil properties. The proposed paper describes the steps necessary for the preparation and the analysis of a multi-year climatic database for the design of a cover system in northern environments. The paper also explains how climate can be classified and how observed variations from one year to the next can be taken into consideration in cover design. The results of climatic records at two different sites are used to illustrate conditions that need to be taken into consideration when designing soil cover systems.

Aug 1, 2010

By E. Mataradze

Statistics shows that the majority of accidents with fatal outcome are caused by methane and/or coal dust explosion. This leads to assume that contemporary counter-explosion systems of various designs cannot be considered effective. Considering the growing threat of methane explosion in the coming years along with the development of deeper levels, the improvement of a system for protecting people in underground opening appears urgent. This paper presents the results of the testing of the Automatic System from Methane Explosion in Coal Mines. The protective system consists of: i) a wireless device for the detection of explosions and activation of a protective system, and ii) an absorber with a pyrotechnic device ensuring the discharge of dispersed water. The protective system, at the command of the initiation signal, produces tailored dispersing water mist with droplet sizes in the range of 25?400 ?m along selected tunnel sections.

Aug 1, 2013

By F. Richards

"The property of the Cariboo Gold Quartz Mining Company; Limited; is in the Wells-Barkerville district of Cariboo mining division. It consists of a group of 106 Crown granted mineral claims and fractions; and extends for over 6 miles along what is termed the Barkerville gold belt. The main portal and mine camp are half a mile south of Wells; which lies at the northeast end of Jack of Clubs lake and is reached by a 55-mile motor road from Quesnel; the northern terminus of the Pacific Great Eastern railway.Gold-bearing quartz veins were discovered on the surface in various parts of the property by different prospectors as far back as 1877, but the work that led to the formation of the present company was performed by Al Sanders in the year 1926. Sanders dug trenches and drove small adits on quartz veins containing gold above what is now known as the Sanders zone. Very little underground work has been done beneath the earliest known discovery-the B.C. vein. The Cariboo Gold Quartz Mining Company was formed in the autumn of 1926. The total production of gold from its beginning in 1933 to the end of 1944 has been as follows:"

Jan 1, 1954

By PAUL L. DEAN

Industrial mineral deposits are widespread in Newfoundland and Labrador and a variety of commodities are produced. The province has the only pyrophyllite mine in Canada and also produces asbestos, gypsum, silica, barite, limestone, gemstones, cement and other structural materials. Large reserves of these and other industrial minerals are known and several deposits are likely future producers. Most producers are wellestablished and have large tonnages of ore reserves.

Jan 1, 1984

By J. A. Vezina

The effects of particle size distribution on metal extraction have been determined from pressure leaching Renzy Mines Limited concentrate with oxygen. Using a pulp density of 30 per cent solids, an oxygen pressure of 80 psig, a temperature of 230°F, a grind of 2.5 hours and a retention of 8 hours resulted in the almost complete dissolution of the nickel and the cobalt and the decomposition of over 96 per cent of the chalcopyrite finer than 20 microns. Only 11 per cent of the chalcopyrite coarser than 20 microns was reduced to smaller than 20 microns.

Jan 1, 1973