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By Derek H. C. Wilton

"The Nain Province (NP) of northern Labrador is a >600 km long by =100 km wide Archean craton that has undergone relatively little mineral exploration until economically signifcant concentrations of orthomagmatic nickel sulphide were discovered by Diamond Fields Resources (DFR) at Voisey’s Bay. Due to the great time span between crust formation andfnal intrusive activity (ca. 3.9 Ga to 1.27 Ga),there were, however, numerous metallogenic events within the NP.The NP was intruded by the ca. 1.3 Ga to1.2 Ga Nain Plutonic Suite (NPS) composite anorthosite-granite complex. The NPS dividesthe NP into the southern Hopedale Block (90 km by 150 km) and the northern SaglekBlock (375 km long by =50 km wide). These two blocks appear to represent two distinct Archean cratonic nuclei, each with its own distinct metallogenic history. The NPS is a coalesced assemblage of composite intrusions which include anorthosite, troctolite, norite, gabbro and granite.The Hopedale Block contains the Hunt River and Florence Lake greenstone belts, and the Weekes Amphibolite which represents remnantsf the older Hunt River greenstone belt. Geologically, these belts have some potential to host komatiitic Kambalda-style nickel, volcanogenic massive sulphide (VMS) and meso -thermal lode gold mineralization. The unconformity between Paleoproterozoic cover sequences and the trondhjemite-tonalite-granodiorite (TTG)suite which engulfed the greenstones was the locus for lead-zinc-bearing quartz-carbonate veins. Minor fracture-hosted uraninite showings are also present in the TTG.The Saglek Block is a high-grade gneissterrane with deformed Archean supracrustal sequences but no greenstone belts. Within the gneiss are variably-sized enclaves that range in composition from anorthositic to ultramafic; some of these latter xenoliths contain abun-dant fuchsite. There are also three small anorthositic to ultramafic meta-igneous complexes present in the gneiss near Okak Bay.Some Archean meta sedimentary and maficgneiss supracrustal sequences contain iron-oxide and sulphide members. The sulphide-bearing Tasiuyak parag neiss defines the cra-tonic suture between the NP and Churchill(Rae) Province. Along the cratonic suture between the NP and Churchill Province from Ramah Bay north are remnants of the Archean(or Paleoproterozoic) Hutton Anortho site Suite. Ultramafc layers within the suite contain chromite and elevated Ni values.Three ca. 2.0 Ga supracrustal sequenceswere deposited in small fault-bounded basins within the NP. The Snyder Group contains pyrrhotitiferous massive sulphide horizons. TheMugford Group contains SEDEX-like massive sulphide blocks in a debris fow and ultramafic sills with unusual PGE concentrations; alaskitic granite cutting basement gneiss to the group contains stockwork-like pyritiferous quartz veins. The Ramah Group contains numerous MVT-style zinc-lead sulphide occurrences.The Reid Brook Intrusion of the NPS contains enormous and high-grade nickel-copper-cobalt massive sulphide bodies at the Voisey’s Bay deposit. Exploration in the northern portions of the NPS in 1995 has indicated the presence of other potentially economic nickel sulphide horizons."

Jan 1, 1996

By E. D. Fox

Introduction The financial statement of the hypothetical Gold Mining Company, which forms the background of this survey, was designed for the Institute with the express abject of having it assessed in respect to Profits by the several taxing bodies representing the Federal and Provincial Governments, which comprise the Dominion of Canada. On the completion of the figures, copies were sent to the several Ministers of Mines, accompanied by a request that they be submitted to their taxing authorities and assessed accordingly. The response, while it was not general, was very favourable, and at all times we were treated with the utmost courtesy and patience, and what has been set forth in the compilation bears the authentication of the various government officials who are immediately concerned with taxation. The data itself constitutes a fairly comprehensive digest of taxation as it directly applies to gold mining profits in Canada. The Hypothetical Balance-Sheet (See Exhibit A) In the balance-sheet schedules 1 and 2 (Exhibit A), income is divided between taxable and non-taxable classifications, and here it should be noted that the division contemplates only the assessment for Dominion income tax. The same applies to the factors of exchange and depletion. Therefore, in making comparisons, it is to be borne in mind that the set-up for assessment to the Provinces, that is, Manitoba and Alberta, will stand as if the gross non-operating income is taxable, with the reservations as shown in the notes below the schedules.

Jan 1, 1934

By A. Sokolov, E. Hasikova, V. Gostilo, V. Titov

Introducing online X-ray fluorescence (XRF) analyzers in the mining and processing industries can lower costs and improve the representativeness and speed of analysis. The applicability of the CON-XTM industrial conveyor XRF analyzer for continuous measurement of potassium content in process materials was demonstrated at various stages of potassium muriate (MOP) production. The CON-X analyzer produced reliable and accurate results for sylvinite ore (27–36% KCl), MOP cake after flotation (88–97% KCl), and NaCl residue (1.5–5% KCl). Tests of the analyzer at an MOP-producing plant showed a < 0.5% difference between online and laboratory results.

Jan 1, 2014

By A. F. Brock

Introduction During the past ten years, shaft sinking has been going on continuously at Inco and new shafts and shaft extensions have been sunk under a broad diversity of conditions. The Murray mine and the Stobie section of the Frood-Stobie mine have?been opened and a main hoisting and supply shaft has been sunk at each of these mines; No. 2 shaft at Murray was sunk initially from surface to 1,960 feet and is now being extended; No. 7 shaft at Stobie was sunk from surface to 3,105 feet. No. 2 shaft at Garson has been extended from 2,200 feet to 3,200 feet in depth. At Levack, No. 2 shaft is being extended from 1,860 feet to 2,850 feet for ore hoisting from the 2,650 lev el. At Creighton, No. 6 shaft, collared on 52 level, was sunk 1,740 feet to a total depth of 5,563 feet below surface. It is the deepest Inco working. At Creighton, also, No. 7 shaft is being sunk from surface to the 30 level to handle the ore from caving operations. Ail Inco main hoisting and supply shafts sunk during the past twenty years have been vertical rectangular shafts equipped with two cages and two ore skips. The cages are standard and interchangeable for all shafts except Garson No. 2; they are single-deck, 13 ft. 4 in. by 5 ft. 2 in. inside and are designed to carry a maximum material load of 16,000 lb. The man load is 48 men. Skip capacities at the several shafts vary from 8 to 15 tons. Forty-two hundred feet bas been established as the standard vertical lift, and the permanent hoisting equipment at each shaft is designed for eventual hoisting from that depth.

Jan 1, 1950

By B. Wasmund, M. Y. Solar, I. Candy

The nickel laterite industry is divided into two camps when it comes to the grade of the ferronickels produced. One group, led by Falcondo and Cerro Matoso, markets high-grade ferronickels in the range of 35 to 40% nickel, while another group, led by SLN and the Japanese smelters, favour lower grades in the range of 20 to 25%. Because the ores processed by these smelters vary widely in terms of nickel content and iron to nickel ratios, it is probably more accurate to classify these smelters in terms of their iron recovery: Falcondo and Cerro Matoso smelt at lower reduction potentials and thus recover only 15 to 30% of the iron in their ores, while SLN and the Japanese smelters are very reducing and recover 45 to 65% of their iron. Low reductions generally imply higher slag losses and lower nickel recoveries, but also lower power and reductant requirements; higher reductions, the reverse. The question is, therefore, whether an economically optimum ferronickel grade exists for processing any given ore. This paper proposes a methodology for determining this optimum grade and concludes that nickel laterite smelters should favour low reductions and production of high-grade ferronickels.

Jan 1, 2008

By K. Barbetti

"The carbon-in-pulp (CIP) process has been the dominant gold recovery process since the early 1980s. CIP has proven to be very adaptable for a wide range of ores and circuit configurations. The key performance indicator for CIP circuits is the minimisation of soluble gold losses to tailings, however, it is also important to operate the circuit efficiently (maximising gold loadings on carbon and minimising carbon inventory). Over the last 30 years the Curtin Gold Technology Group has studied CIP circuits as part of an on-going collaborative industry funded project (the AMIRA Gold Processing Technology Project). In the early years the project undertook basic research into understanding activated carbon, and its management in the circuit. More recently the development of process models and instrumentation has provided additional tools to assist operators. The results show that while most CIP circuits operate well, there are still significant opportunities for further cost savings, or additional revenue. This paper reviews the observations arising from this work, including key requirements for good carbon management, the results of benchmarking and industry surveys of carbon circuit over 20 years, the value of process modelling of CIP circuits to establish operating parameters, and the use of automated instrumentation to better optimise carbon control in the circuit.INTRODUCTION The introduction of activated carbon to recover gold from cyanide leach solutions in the last quarter of the 20th century was the most significant development in gold ore processing since the advent of cyanidation seventy years before. Replacing the Merrill–Crowe zinc cementation step with carbon-in-pulp (CIP) or carbon-in-leach (CIL) circuits provided a process that allowed the treatment of lower grade and problematic ores (e.g. high-clay ores), at lower capital and operating costs, and higher metal recoveries. The CIP circuit was first developed in the 1950s at the Carlton Mill, Cripple Creek, Colorado. All the components of the modern CIP process came to fruition at the Homestake Mine in South Dakota in 1973 (Fast, 1988). From the late 1970s onward a variation of CIP, carbon-in-leach (CIL) which combined the leach and adsorption stages, became the preferred circuit design in most parts of the word."

Jan 1, 2017

By T. W. Wlodek

Abstract A simplified method of fatigue testing full-dimension, as-rolled, non-machined, mining drill rods is very desirable to the mining and steel industries in the classification of steels available on the market, through the evaluation of their fatigue limits and endurance strength. In this paper one such simplified method is presented and analysed. The preliminary results show many advantages of this method, such as simplicity and constancy of loading. The type of loading applied more or less simulates the working conditions of the outside fibres of the mining drill rods. Additional advantages of this method are the possibility of testing under dry and wet conditions, its quietness, and its ease of operation. Specially designed adaptors and specially applied techniques of fixing and preparation of samples make possible the breaking of a quarter-octagon hollow drill rod in a free length of uniform section in a rotating beam machine. At first glance this seems to be difficult to achieve. In the first preliminary test three different lots of steel were used. S-N curves under dry conditions were determined. These curves permit of the classification of the drill rods on the basis of the fatigue limit and endurance strength of the outside fibres of the metal, which is dependent to a greater or lesser extent on the effect of surface decarburization, surface imperfections, and special surface treatments. The average slope of the S.N curve in the damaging zone, and the fatigue limit in equal tension-compression rotating bending, were determined for SAE 1080, chromium-molybdenum and nickel-chromium-molybdenum mining drill rods. INTRODUCTION The fatigue limit and the endurance strength of mining drill rod steels are of interest to both the mining and the steel industries. These industries are greatly interested in lowering the cost of mining by reducing the consumption of these steels per ton of ore exploited.

Jan 1, 1951

By A. Warczok, T. A. Utigard

"Slags from smelting of copper concentrates contains from 1 to 15% of copper. Copper is present in the form of copper or copper matte inclusions of size from 2 to 1000 micro, and as dissolved cuprous oxide. Removal of the copper requires the slag reduction, primarily reduction of magnetite and co-reduction of cuprous oxide. Thus, the kinetics of the slag reduction play an important role in copper recovery. Instantaneously, at the contact of carbon and a slag the gaseous film is formed. The magnetite and cuprous oxide reduction is going through a gaseous film, separating the slag and carbon of a coke or electrodes. The thickness of a gaseous film grows to a critical value and gas bubbles, containing CO and CO2, are created and rise up in the slag. Results of measurements of kinetic of the slag reduction with graphite showed high value of activation energy, close to the value of activation energy of Boudouard reaction. Strong temperature dependence of the reaction rate points out the thermal instability of the reacting system. It was found that the slowest process in the reduction stages determines the loop of CO and CO2 transfer and magnetite diffusion to the slag/gas film boundary. Strongly endothermic Boudouard reaction seems to cause thermal instability on the reaction surface. So, heat transfer to the reaction surface is very important. Due to low thermal conductivity of a slag the convection dominates in the heat transfer. So, any slag stirring accelerates the rate of reduction and coalescence of metallic copper or copper matte inclusions."

Jan 1, 2015

By The Staff

BEFORE going into detail on the subject to be presented, a brief outline of the Company&apos;s earl y history would not be out of place. Prospecting and mining on a small scale was started in 1876 on the site of the present open pit at Thetford Mines. The property was purchased from the Crown in 1878 and Johnson&apos;s Company was incorporated in 1885. It is owned and operated today by descendants of the original shareholders. Many employees, through their fathers and grandfathers, have service records dating back three generations. The principal asbestos deposit at Thetford Mines is pear-shaped, with surface dimensions of about 2,200 feet in length by 1,300 feet in maximum . width. Its long axis strikes northeast and the dip is nearly vertical, but irregular in detail. It is known to extend to a depth 1,200 feet below the original surface, but its area at that depth has not been determined. Ownership of this deposit is divided among three active Companies: the Asbestos Corporation, Limited; Bell Asbestos Mines, Limited; and John-son&apos;s Company. Johnson&apos;s Company owns a section about 1,000 feet in length and 500 feet in width, bounded on the northeast by the King mine of the Asbestos Corporation and on the northwest by the Bell pit. On Johnson ground, there was originally a large outcrop o~ asbestos rock which dipped toward the south below overburden. This was mined until recently by open pit, the overburden being stripped off as far southward from the original outcrop as was economically possible. As the. pit was deepened, within side walls maintained at a maximum safe slope, its floor area, of course, became progressively smaller, and eventually the pit would have wedged out against the Bell property line. It became necessary, there-fore, to introduce some other method of mining before production became seriously curtailed by a shrinkage of the pit area.

Jan 1, 1941

Automation Defined ?Using self-operating equipment to reduce human exposure to the mining environment and routine or repetitive work.?-Atlas Copco Terminology: ?Manual Operation ?A vehicle being operated by a person ?in the cab?. ?Radio Remote Control (RRC) ?A vehicle being physically operated by a person through a Line Of Sight (LOS) or Video-Remote equipment. ?Tele-Remote Control ?A vehicle being physically operated by a person at an operator station which is not necessarily located near the vehicle?s working area. ?Autonomous Operation ?A vehicle under self control with the possibility of human supervision and override.

Oct 1, 2010

By A. A. Millar

THE output of coal from the Province of Alberta reached its peak; in the year 1928, when 7,334,179 tons were produced. Following this, a steady decline was recorded, and in 1930 a low mark of 4,564, 290 tons was made. Since that time, however, the tendency has been upward, and this year (1937) 5,551,682 tons were produced, compared with 5,696, 375 tons in 1936 and 5,462,973 tons in 1935. The value of the output in 1937 was $14,434,969, against $14, 720,004 in 1936. The coals of Alberta have been classed under three heads, viz., domestic, sub-bituminous, and bituminous The domestic (or lignite) and the sub-bituminous coals are used chiefly for domestic purposes, with the possible exception of the smaller sizes and the output of the two stripping pits at Stereo and Coal Valley The bituminous output is used mainly by the railways, for locomotive purposes, which, in 1937, accounted for 80.6 per? cenr of the total sales of bituminous coal. A fair proportion is sold for stationary engine and steam purposes and, in 1937, 25,000 tons were used in making briquettes at plants operated by the Canmore Coal Company, Limited, and Brazeau Collieries, Limited. The International Coal & Coke Company, Limited, used 99,500 tons in their plant at Coleman, for making coke. The bulk of the 66,000 tons of coke produced was sold for use at the smelter at Trail, B.C.

Jan 1, 1938

By S. K. Shaha, W. Kasprzak, D. L. Chen, J. Friedman, F. Czerwinski

The role of solutionizing conditions within the T6 heat treatment of the cast Al-Si-Cu-Mg alloy with micro-additions of Zr-Ti-V was assessed in terms of their influence on microstructure and mechanical properties. As a solution treatment, a single step process at 485 and 510oC and a two-step process at 510 and 525oC for varying time intervals from 0.5 to 9 h, were examined. In all cases, solution treatment was followed by isothermal aging at 150oC for 100 h. The microstructural analysis showed that the solution treatment changed the eutectic silicon morphology from needle-like, present after casting, to spherical shape in the T6 state and that the extent of changes was strongly influenced by temperature and time. The Cu- and Mg-rich phases completely dissolved during solution treatment while the Fe-containing phase, Al8Si6Mg3Fe, remained partially in the microstructure. The Ti, V and Zr containing phases, Al13Si2Ti3Zr and Al3Si26FeTiV10, present in as-cast state, were partially dissolved during solution treatment, reducing their size by 10 - 48%. The studied alloy reached the maximum ultimate tensile strength of 335 MPa and yield stress of 303 MPa for two-step solutionizing with a total time of 4.5 h. It is concluded that the two-step solution treatment resulted in higher tensile properties than the single-step process.

Jan 1, 2015

By Rosie Moore, Harvey Keats, Kerry Sparkes, A. J. Naldrett

"Abstract-The Voisey’s Bay Ni-Cu-Co deposit was discovered in late 1994 as the result of prospecting initiated in the summer of 1993. By July 1995, proven mineable reserves were 31.7 x 106 tonnes grading 2.83% Ni, 1.68% Cu and 0.12% Co, and current total resources in all categories are quoted to be in the order of 150 X 106 tonnes. The deposit is associated with a body of troctolite belonging to the Nain Anorthosite (1.35 Ga - 1.29 Ga) suite, which was emplaced across the boundary between the Proterozoic "Rae" Province to the west and Archean "Nain" Province to the east.The deposit can be described in terms of three geological settings. The "Ovoid" is a 600 m long by 350 m wide by 100 m deep lens of massive sulfide, covered by 10 m to 20 m of glacial overburden, and separated from the underlying country rock quartz-plagioclase-biotite gneiss by a breccia of gneissic fragments in troctolite known as the Basal Breccia Sequence. To the west of the Ovoid lies the "Western Extension", comprising disseminated and massive sulfides in a north-dipping sheet of troctolite which ranges from upper unmineralized troctolite down through troctolite with increasing amounts of sulfide (up to 50%), to massive sulfide (in some places only), and then to Basal Breccia Sequence. East of the Ovoid, the troctolite sheet broadens out into a troctolite intrusion, within which occurs the "Eastern Deeps", a zone of massive and disseminated sulfide up to 100 m thick that is currently being explored. The mineralization of the Eastern Deeps lies along the line of intersection of a feeder sheet with the base of the intrusion. The current interpretation is that the three geological environments represent different erosional levels through a single mineralized intrusion. In this model, the deepest erosional level lies to the west and exposes the feeder to surface, whereas the Ovoid represents the base of the intrusion at surface, and the Eastern Deeps the base of the intrusion overlain by 600 m to 900 m of troctolite. Sulfides and gneissic fragments were brought up by magma flowing quickly through the feeder, and settled out where the flow rate decreased as the sulfide-bearing magma mixed with magma already emplaced in the intrusive body."

Jan 1, 1996

By H. Groeneveld, C. A. Connally, P. J. Hoenmans, W. L. Mason, John J. Justen

"A miscible displacement pilot, using a slug of LPG driven by separator gas, was conducted in the Cardium Reservoir of the Pembina Field. The injection pattern was a 10-acre, inverted, isolated five-spot. Upon completion of the LPG-gas phase, an .experiment was conducted using a slug of water followed by gas. Calculated performance of the pilot is compared with actual performance. Equations are developed to cakulate the distribution of LPG into zones of varying permeability, to estimate the progress of the flood at different times in the various zones, and to estimate gas rates after breakthrough. The analysis indicates that permeability stratification was a dominant factor in con-trolling oil recovery and that oil was completely displaced from the swept pore volume. The results of the pilot indicated that miscible flooding is a practical means of pressure maintenance in this reservoir. The total recovery from the pilot area was good in spite of the early breakthrough of LPG. The effects of stratification were reduced by injecting a slug of water into the partially swept reservoir."

Jan 1, 1960

By J. O'Leary, R. Cannell, D. Honsberger

"The Scully Mine deposit lies within the group of metasediments that together comprise the rocks of the Labrador Trough. The ore itself still retains the bedding characteristics of the parent rocks and on this basis has been divided into three main members, namely: Upper, Middle and Lower. The Upper and Lower both show many of the bedding characteristics of the cherty taconites of the northern U.S.A.; the Middle member is a coarse-grained friable specularite rock. The ore minerals are hematite (normally present in the specular variety) and magnetite, although the latter rarely occurs in concentrations greater than 20 per cent. Gangue minerals are quartz and the hydrated iron oxides. Manganese oxides also occur as accessory minerals. The outcrop area of the orebody is in excess of 2 square miles, displaying a complex pattern of faulting and folding, which has been formed as a result of at least two orogenic periods."

Jan 1, 1972

By Carl O. Nickle

"IntroductionIF I WERE ASKED what are the two most important single factors in shaping the growth of Canada to date, and in building its future, the answer would be: first, the treasure house of natural resources on and below the surface over the length and breadth of our country; and two, the pioneering spirit and 'get up and go' of many of our people. The two factors are inseparable. Without the pioneering spirit, the natural resources of land, forest, stream, and the subsurface would have continued •to be useless,. Idle assets. With the pioneering spirit, Canada's natural resources have been and are creating economic revolutions.Western Canada oil and natural gas rank high on the list of such revolutions. Calgary, your meeting place today, is the birthplace of this economic revolution, one that has already sharply altered the economy .of the middle half of Canada, particularly that of Alberta; is increasingly making its weight felt on the economy of all Canada; and is helping re-shape world thinking on sources of vital petroleum supply for both peace and war. Calgary is today the 'operation headquarters' for the great bulk of a huge exploration and development programme that now extends over a quarter of a million square miles of Canada's West. As a Calgarian, •therefore, I am particularly happy to have this privilege of talking about oil and natural gas to members of the C.I.M.M., who play a key role in the development of all Canada's varied natural resources."

Jan 1, 1952

By Marcondes Lima Costa

Abstract-The Amazon region is characterized by the development of deep chemical weathering represented by widespread lateritic covers and soils. Two distinct periods of laterite formation can be distinguished: mature laterites from the Eocene-Oligocene (and locally from the end of the Cretaceous), and immature laterites from the Pleistocene. The older laterites occur on plateau landscapes, and the younger ones on widespread hilly to flat lowlands. Both types show complete or truncated profiles, generally covered by deep yellow to brown topsoils. The mature laterite profiles contain high concentrations of gibbsite and/or aluminum phosphate, whereas the immature ones are poor in these minerals. The Amazon region is rich in mineral deposits related to lateritic profiles. Some mineral deposits are of primary origin but were concentrated to economic grades by lateritic processes. The most important ore deposits are of iron, aluminum (bauxite), kaolin, manganese, gold, nickel, copper and phosphate. These are mainly related to mature profiles. The wide spectrum of ore deposits and mineralogical and geochemical complexity of the Amazon laterites has been promoted by: (1) the prevalence of ideal conditions for laterite formation throughout much of the Tertiary; (2) the presence of varied basement lithologies due to contrasting geological environments; and (3) a variety of epigenetic alteration types. The lateritic profiles show a well-developed ore zonation which is related to specific lateritic horizons. Iron and gold deposits occur in the ferruginous horizon, which is nearest the surface; the central aluminous horizon hosts bauxites, aluminum phosphate, strontium and gold; and the lower clayey horizon contains deposits of manganese, nickel, copper and kaolin. Resistate phases which residually accumulate throughout entire profiles include titanium (as ilmenite and anatase), chromium (as chromite), tin (as cassiterite), yttrium (as xenotime), and niobium (mainly as ilmenorutile). Epigenetic alteration, caused by swamp environments developed above truncated lateritic profiles, has led to the formation of high-grade kaolin and refractory bauxites. The laterites in the Amazon region contain most of all known kinds of ore mineralization related to laterite processes.

Jan 1, 1997

By Marcondes Lima Costa

The Amazon region is characterized by the development of deep chemical weathering represented by widespread lateritic covers and soils. Two distinct periods of laterite formation can be distinguished: mature laterites from the Eocene-Oligocene (and locally from the end of the Cretaceous), and immature laterites from the Pleistocene. The older laterites occur on plateau landscapes,and the younger ones on widespread hilly to ?at lowlands. Both types show complete or truncated pro?les, generally covered by deep yellow to brown topsoils. The mature laterite pro?les contain high concentrations of gibbsite and/or aluminum phosphate, whereas the immature ones are poor in these minerals. The Amazon region is rich in mineral deposits related to lateritic pro?les. Some mineral deposits are of primary origin but were concentrated to economic grades by lateritic processes. The most important ore deposits are of iron, aluminum (bauxite), kaolin, manganese, gold, nickel, copper and phosphate. These are mainly related to mature pro?les. The wide spectrum of ore deposits and mineralogical and geochemical complexity of the Amazon laterites has been promoted by: (1) the prevalence of ideal conditions for laterite formation throughout much of the Tertiary; (2) the presence of varied basement lithologies due to contrasting geological environments; and (3) a variety of epi-genetic alteration types. The lateritic pro?les show a well-developed ore zonation which is related to speci?c lateritic horizons. Iron and gold deposits occur in the ferruginous horizon, which is nearest the surface; the central aluminous horizon hosts bauxites, aluminum phosphate, strontium and gold;and the lower clayey horizon contains deposits of manganese, nickel, copper and kaolin. Resistate phases which residually accumulate throughout entire pro?les include titanium (as ilmenite andanatase), chromium (as chromite), tin (as cassiterite), yttrium (as xenotime), and niobium (mainly asilmenorutile). Epigenetic alteration, caused by swamp environments developed above truncated lateritic pro?les, has led to the formation of high-grade kaolin and refractory bauxites. The laterites inthe Amazon region contain most of all known kinds of ore mineralization related to laterite processes.

Jan 1, 1997

By Norman A. Grant

"Location and Transportation FacilitiesTHE BEAVERLODGE area of North Saskatchewan is on the north side of lake Athabasca, 500 air miles northeast of Edmonton.The main Eldorado operation and townsite are on the north •side of Beaverlodge lake, which is immediately north of lake Athabasca and is separated from it by only a mile long portage at Lodge bay. The once famous town of Goldfields. Saskatchewan, and the Box property of the Consolidated Mining and Smelting Company of Canada, Limited, are located on lake Athabasca nine mines from Beaverlodge townsite.Previously, all Eldorado freight was delivered by barge at the Lodge Bay portage, hauled across the portage, and across Beaverlodge lake by small Northern Transportation Company barges, which involved many handlings.In 1952 the port of 'Bushell' was established at Black bay. This is a particularly snug harbour, well protected from the main body of the lake and with good foundations for docking facilities. A Butler building, 300 ft. by 60 ft., and tank farms provide storage at the port. A •road from Bushell to the main Beaverlodge operation, a distance of twelve miles through rugged terrain, was built by the Saskatchewan Government. The cost was shared by the Saskatchewan Government, the Federal Government, and Eldorado and other mining companies.Along this road are located the properties of several enterprising mining companies and near the midpoint lies the ambitious budding town of Uranium. This road has made portaging unnecessary and palletized freight loaded at Waterways, Alta., is now loaded directly on trucks at Bushell and delivered to the point of consumption."

Jan 1, 1953

By E. Asselin

Electrochemical polarization experiments were conducted on alloy 625 in ammonia solution between 25 and 225°C and the results were compared with those of an oxygen solubility model. Results confirm that corrosion is under oxygen control, Normalized corrosion rates are determined based on the rate of oxygen diffusion to the corroding surface, and the corrosion rate at 200°C (-9.7 µA.cm-2) is roughly 24 times higher than the corrosion rate at 25°C (0.4 nA,cm-2), An oxygen-solubility model for Supercritical Water Oxidation (SCWO) conditions was generated using the Redlich¬Kwong-Soave (RKS) equation of state, Results of the model confirm many of the experimental observations from SCWO reactors which suggest that corrosion is at a maximum at temperatures just short of the critical point, The RKS/oxygen diffusion model predicts that the corrosion rate at 365° C is ?85 times higher than the corrosion rate at 25&apos; C. Given that a normalized corrosion rate is obtained, this type of model could be useful for selection of SCWO reactor materials.

Jan 1, 2005