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By T. G. Ewart

INTRODUCTION FOR THE purpose of this paper, western bituminous coal is defined as steam coal produced in Alberta and southeastern British Columbia for sale primarily to railways and industries. Before examining present and future markets of this industry, it is proper to review briefly financial and operating conditions within the industry. The report of the Royal Commission on Coal, 1946, supplies financial data from which some conclusions may be drawn. In 1944, the industry as defined above had share capital of $24,886,696. In the fifteen years 1930 to 1944, inclusive, the industry produced: 44,364,211 tons of coal. The profit on this tonnage amounted to $4,678,382.58, which represented 10.6 cents per ton of production. Miscellaneous earnings increased the amount available for dividends to shareholders to a total of $8,487,952.41, which is equal to, 19.1 cents per ton of production. Dividends actually paid in this fifteen-year period amounted to $12,332,040.64, which represented an annual average rate of 3.40 per cent on share capital. It is worthy of note that, in 1944, the net current position of the industry, including investments, was $8,753,874.51. The writer believes that the financial position of the industry with respect to capital, current financial position, and net earnings, has not significantly changed from the fifteen-year period out-lined above. The figures quoted indicate the following situation: (1) The western bituminous coal industry is adequately financed. (2) The industry has followed a conservative dividend policy and has accrued funds for contingencies. (3) The industry has sold its production at very reasonable prices as evidenced by its moderate earnings per ton of production.

Jan 1, 1951

By J. D. R. Neilsen

The objective of the research conducted and presented herein was to determine the effect of pre-established free gas saturation on the sweep efficiency of an isolated inverted five-spot well pattern. The investigation concluded that the ultimate recovery of an isolated inverted five-spot may be slightly increased by establishing a free gas saturation prior to water flooding; however, of more significance is the extreme deviation of the pattern's performance after water break-through from that commonly obtained from developed well patterns. The rapid "water-out" characteristic common to both linear floods and floods conducted in developed well patterns was not evidenced in the isolated inverted five-spot. Instead, the wells continued to produce oil long after breakthrough until ultimate areal sweep efficiencies of four, five, and six hundred percent were obtained prior to the water-oil ratio becoming excessive.

Jan 1, 1962

By L. Zeng, Q. Feng, Z. Qiu, L. Ou, Central South University

It is well-known that the use of nanobubbles can significantly improve the flotation efficiency of ultra-fine particles. However, this is mainly focused on coal and phosphate rock flotation. In the field of nonferrous metal processing, the related research is few. In this paper, a small laboratory mechanical cell associated with a specially-designed nanobubbles generator was used to investigate the effects of nanobubbles on enhancing ultra-fine scheelite flotation. Nanobubbles were created and based on the hydrodynamic cavitation principle through Venturi tubes. Comparative flotation tests were performed using different tubes to evaluate the nanobubbles impact on the ultra-fine scheelite particle flotation recovery. In order to better understand the nanobubbles enhanced ultra-fine scheelite flotation, nanobubbles potential and size distribution were measured. The effect of nanobubbles on the particle aggregation and scheelite particles potential were also studied through the turbidity tests, microscope tests and zeta potential measurements. According to the results, the mean size of nanobubbles was about several hundred nanometers, and the surface of nanobubbles was of highly negative charge in alkaline conditions. The flotation recovery of ultra-fine scheelite particles was increased in the presence of nanobubbles. The zeta potential measurements indicated that the repulsive forces between scheelite particles decreased when nanobubbles existed. Through the turbidity tests and microscope tests, the promotion effect of nanobubbles on particle coagulation could be verified more directly. The existence of nanobubbles in flotation system promotes the particle aggregation, thus increasing particles apparent size and particles capture by bubbles, which may be the fundamental reason why nanobubbles enhance ultra-fine scheelite flotation.

Jan 1, 2016

By Ahmad Ghahremaninezhad, Denver H. Cowan

Much of today’s gold is locked within sulphide minerals. These sulphide minerals, including pyrite, need to be subjected to oxidative pre-treatment in order to leach the refractory-gold using traditional methods. Typically autoclaves employing high temperatures between 180?225 ºC, and extremely high pressures between 1,500?3,200 kPa, are used for the oxidative pre-treatment. However, the autoclaves themselves are very expensive, costly to operate and maintain, and produce excess sulphuric acid. This paper studies the atmospheric oxidation of pyrite in ferric sulphate solutions. In general, pyrite oxidation under atmospheric pressure can result in high elemental sulphur production, i.e. less acid generation. Activated carbon has displayed an ability to catalyze the process, achieving reasonable kinetics. The reaction kinetics were investigated by altering acidity of the leaching solution, temperature, catalyst ratio, sparged oxygen and agitation. A combination of X-ray diffraction, scanning electron microscopy, optical microscopy, X-ray fluorescence, inductively coupled plasma mass spectrometry (ICP-MS), and atomic absorption spectroscopy (AAS) were used to monitor the kinetics of the process and elemental sulphur yield. The purpose of this investigation was to determine optimal operating conditions that maximized kinetics of the atmospheric oxidation while maximizing elemental sulphur yield.

Jan 1, 2015

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 Anton Gronningsater

AT the present time we hear a great deal about organization of labour, collective bargaining, workmen's councils, and company unions; about C.1.0. with its principle of vertical unions and A.F.L., largely based on craft unions; and about provincial and federal laws for protection of labour's right to collective bargaining. What we perhaps hear too little about is corresponding organization of the employers, although it recently is mentioned more frequently. I will only mention W. H. Davis, Chairman of the United States War Labour Board, who has had and is having plenty of experience in this field and has also studied labour conditions in Europe-in Sweden for instance. He has repeatedly expressed the opinion that where employer-employee problems are involved, a thing badly needed in America is organization of employers as well as employees to get some order in the present chaos. With this I agree. I believe a strong organization on one side necessitates a correspondingly strong organization on the other side; that has at least been the experience in the industrialized countries in Europe. I happen to be fairly familiar with conditions in Norway, where they have struggled with these problems for fifty years, and a talk on the history, development, and present state of employer-employee relations in that country might perhaps be of interest as giving a general picture of the development of such relations in the northwestern European countries as a whole. The talk was originally given to the Fourth Year students in Mining and Metallurgy at the University of Toronto. I have changed it somewhat to fit a different audience, but I hope you will make allowances if you now and then are reminded of the school auditorium. I will try to be as objective and factual as possible, but it is probably unavoidable that some of what is said is coloured by personal opinion.

Jan 1, 1943

By W. J. Kempson

In recent years, substantial progress has been made with respect to the definition and control of the primary energy requirements in underground mines. Little has, however been done to develop a more detailed understanding of how to limit the various pressure losses which are intrinsic to shaft systems. This is in spite of the fact that more than half of the pressures generated by the ventilation fans in deep level mines are dissipated as pressure losses within the shaft system. This paper presents research which has been completed to optimise the pressure losses which occur in shaft systems as a result of the ventilation air flowing through them. In this regard, the response of various shafts to the ventilation air flowing through them was measured. These results were evaluated against the current theory for the calculation of shaft pressure losses. Finally the results of the measurements and calculations were used to calibrate a Computational Fluid Dynamics model of the shaft systems. This model was then iterated to allow meaningful conclusions as to the specific make up of the shaft equipment which contributes the most to pressure losses in shaft The results of the above analysis demonstrated that the current theory used for the evaluation of these pressure losses is deficient. The paper discusses these conclusions and the specific ramifications of the analysis. Finally, the understandings gained with regards to the above research are applied to the design and layout of equipment in mine shafts. In this regard, the shape and orientation of the shaft steelwork is evaluated and it specific interaction with the piping and conveyance is evaluated. Coming out of this evaluation are specific recommendations for the design of future shaft systems. These recommendations are based on the above models and offer specific savings on the lifetime operating costs of shaft systems.

Aug 1, 2013

By N. Saracoglu, J. P. Golightly, R. H. Wallis, J. J. Brummer

"In January 1974, the Minerals Division of Canadian Occidental Petroleum Ltd. made the strategic decision to add uranium to its active exploration commodities and through compilation studies selected northern Saskatchewan as the most attractive and cost-effective exploration area in Canada. In August 1974, 100 sq. miles were staked adjacent to Gulf Minerals' Rabbit Lake deposit and east of the Esso Minerals Midwest boulder train. Initial exploration was based on geologic models of the Rabbit Lake deposit.In the summer of 1975, surface surveys delineated radon anomalies which were drilled that winter and found to overlie anomalous concentrations of uranium in the regolith which forms the upper unit of the crystalline basement. Within the crystalline basement, one hole intersected graphite and pyrite with anomalous nickel-cobalt-arsenic. Geochemical and radiometric surveys followed in the summer of 1976. Drilling in the winter of 1977 intersected several zones of graphite and also anomalous, but uneconomic, uranium abundances. Also in 1977, Dahlkamp and Tan (1977) described the coincidence of graphite and uranium at Key Lake and ground EM surveys on CanadianOxy claims detected graphite conductors beneath 250 ft of Athabasca sandstone. Inco Limited joined the project in April 1977 as a 50% partner. The project area was then surveyed using the airborne INPUT EM method, which detected 84 miles of conductors, with associated graphitic metasediments. On the ground these were located with MaxMin surveys, and follow-up drilling located the ""Tent"" Lake uranium zone.In 1978, the Midwest and Dawn Lake discoveries were announced, 7 miles and 2 miles west of the Joint Venture (J.V.) claims; and, in part for this reason, the 1979 winter drilling was concentrated on the deeper west side of the property. Exploration hole 102-79 intersected altered and uraniferous rocks, but stepout holes were barren. Drill hole 153-79 tested an under-snow three-station radon anomaly east of hole 102-79 and intersected 33 feet of 7.51 % U3O8, confirming the disco very of the McClean North zone. The geophysical grid of the McClean North conductor system was extended and detailed a strong, continous conductor to the south, called McClean South. This was drilled in January 1980and hole 1004-80intersected 22 feet of 2.95% U3O8."

Jan 1, 1983

By Gaston Gendreau

CETTE PRÉSENTATION traitera des différentes phases des opérations de la mine du Mont-Wright depuis ses débuts jusqu'à présent. A une brève description de la géologie du gisement, suivra un exposé des méthodes d'exploitation de la mine et du genre d'équipement utilize.

Jan 1, 1977

By Zhen Lei

In Alberta, Canada, heavy industrial projects are constructed using a prefabrication approach: spools and pipes are produced in the factory, and are assembled into modules that are transported to the industrial plants for installation by mobile cranes. Planning the onsite mobile crane operations is critical to the project budget and schedule. However, due to the large magnitude of industrial projects, manual heavy lift planning is tedious, and the results are not particularly responsive to site changes. This paper introduces an integrated mobile crane management system developed by PCL Industrial Management Inc., in collaboration with the University of Alberta, which investigates crane location selection and path checking for field module assembly. The project information is stored in a database, and the proposed system retrieves data, performs the calculations, and records the results back to the database; the calculations involve automatically selecting locations for the mobile crane, considering the crane capacity, lifting range and utilization. Lift paths for modules are checked for feasibility based on selected locations, satisfying the site and crane configuration constraints, and crane walking paths are planned if needed. The designed system is tested in an industrial project to validate the effectiveness of the system.

Aug 1, 2013

By A. Lopez-Valdivieso

Particle size enlargement processes play an important role in solid/liquid separation, and in beneficiation unit operations. In the latter, not only the size of the formed aggregates but also their surface properties are very important. Oil agglomeration has a special place among such processes: it is a selective process in which hydrophobic particles are agglomerated into hydrophobic agglomerates which can be recovered by flotation. This explains the broad applications of oil-assisted beneficiation processes not only in the beneficiation of fine coal, but also in agglomerate flotation of many different types of ores, and in coal/gold agglomeration.

Jan 1, 2004

By Robert J. Shank

This paper describes the Federal Government assistance available for northern mining development. The paper commences with a discussion of why the Federal Government should give assistance to northern mining development. It then uses a hypothetical case of a company which has a property it wants to develop to list the sectors within the . Federal Government that would have to be consulted in order to obtain federal financial assistance. The paper also outlines the type of information a company must be willing to provide the government in order to qualify for such assistance.

Jan 1, 1978

By A. E. Gran

"QIT -Fer et Titane Inc. currently produces and markets four main products: a titania slag named SORELSLAG for the white pigment production, a high purity pig iron known as SOREL-METAL mainly used in the ductile iron casting industry, an ilmenite ore for blast furnace applications called SORELFLUX and high quality steel billets SORELSTEEL employed in the wire rod fabrication. Moreover , QIT also manufactures high quality iron and steel powders labeled ATOMET for the powder metallurgy industry through its wholly owned affiliate. Quebec Metal Powders Limited. The company operates. rock ilmenite mine near Havre St. Pierre and produces its slag and ferrous products from its metallurgical installations located in the Sorel/Tracy region. QIT. born in 1948 from a joint-venture between Kennecott Copper Corporation and New Jersey Zinc Company, was acquired from BP Minerals by RTZ Corporation PLC in 1989 and remains its wholly owned subsidiary ever since.lImenite is a mineral rich in both titanium and iron oxides. QIT's proprietary mineral enrichment and electric smelting processes permit the concentration of the ilmenite ore and the separation of its main constituents to produce a 80% TiO2, slag and a high purity molten iron which is further transformed into iron ingots (pigs), steel billets, iron and steel powders.QIT's ilmenite deposit is located in the Lake TIo-A1Iard area, 43 km inIand from Havre St. Pierre, a community on the north shore of the St. Lawrence River some 960 km from Montreal. The orebody, covering some 542 000 m2, consists primarily of coarse-grained ilmenite (FeO.TiO2) with disseminated fine lenses of hematite (Fe2O3). The worthless mineral (gangue) associated with ilmenite is mainly anorthosite, a complex silicate. QITs mining operations are carried out using conventional open pit methods in a 500 m by 600 m horse-shoe shaped mine with nine benches developed. Primary blasting is performed on a weekly basis during the mining season. Blasted ore is trucked to the crushing station to be broken down to 15 cm and 7.5 cm sizes, respectively, by means of a primary jaw crusher and a secondary cone crusher. Minus 7.S cm ilmenite is then loaded into hopper cars for the 43 km trip to the Havre St. Pierre terminal where it is stockpiled and reclaimed by under-ground conveyor chutes to a ship loading tower at the dock. The crushed ore is shipped to QIT's smelter located in Sorel in 40 000 tonne carriers from April to December."

Jan 1, 1995

By N. E. Izatt

Molecular recognition technology (MRT) has a wide range of applications in the hydrometallurgical and chemical processing industries for the selective removal of iron as well as various other impurities from a variety of streams, including aqueous solutions through a wide pH range, as well as organic solutions. An example of a commercial application is provided for the removal of iron from an aluminum chlorohydrate stream. In this example, MRT has a selectivity for iron relative to aluminum which is significantly higher than that of ion exchange resins. A discussion of MRT capabilities for other impurities and streams is also provided.

Jan 1, 2006

By Patricia J. Dillon

Established in 1997, Prospectors and Developers Association of Canada Mining Matters (PDACMM) is a registered charitable organization dedicated to providing Earth Science education to grade school students. Through the development and distribution of educational programs and materials, PDACMM informs students of Canada?s geology and mineral resources as well as promoting awareness of the importance of rocks, minerals, metals and the mining industry. PDACMM also co-ordinates with other charitable organizations and government agencies to provide support or to work in tandem with them and reach as many young people as possible. Although PDACMM became a charitable organization in 1997, it actually has its? roots in 1994 when the Grade 7 program Mining Matters/Une Mine de Renseignments was developed to help teachers bring geology and mining into the classroom. Over 2100 of these resource kits were distributed to teachers across Ontario during the period 1995 to 1998. This unit won national recognition when it received the prestigious Partnership Focus award from the Conference Board of Canada for ?promoting science literacy for the world of work?. Due to the phenomenal success of these kits, a Grade 4 kit entitled Deeper and Deeper/Aller au Fond Des Choses was developed in 1998 in response to the opportunity provided by the new Ontario curriculum released at that time. Over 2600 of these kits were distributed throughout Ontario and there is a substantial waiting list of teachers hoping PDACMM will be able to raise enough money for another print run.

May 1, 2002

By W. A. Bell

The Carboniferous system of rocks in the Maritime Provinces include as workable mineral and organic substances, gypsum, anhydrite, salt, coal, building stones, grindstones, limestones, brick-clay shales, fire-clay shales, oil shales, etc. The system is, therefore, pre-eminently of economic value to the provinces in which it occurs, and the more knowledge we may gain concerning it, the more we may be prepared to aid in the development of these useful substances. For this purpose it is not sufficient to state that the ground upon which we stand is underlain by Carboniferous rocks. In-discriminate digging or drilling will not open many new mines of wealth, however difficult it may be to dampen the optimism of gamblers. For mineral wealth has not been scattered in the rocks haphazard, now here, now there, but its distribution has been the result of natural earth forces acting at intervals throughout the countless millions of years that have elapsed since our planet was born. As regards the majority of metalliferous deposits, the earth forces involved have resulted in the penetration of surface or sub-surface rocks by molten rock-matter and associated mineral solutions from deep-seated sources. But the economic Carboniferous deposits that have been mentioned are themselves types of bedded surface rocks rather than immigrant deposits, and their formation and geological history is closely related to that of the rocks with which they are interbedded.

Jan 1, 1924

By E. O. Magnusson

THE orebodies of the Preston East Dome mine show a considerable variation in size,? shape, dip, and ground condition. They vary from small and large irregular masses being mined by shrinkage, cut-and-fill, and square set-and-fill mining methods to narrow veins being mined by open stoping. Standardization of mining operations has necessarily been difficult. This considerable variation in mining condition prompted the development of a bonus system which would give more equitable bonus payments through-out the mine than those obtained by the usually accepted methods of calculating mine bonus. PRINCIPLES ON WHICH THE SYSTEM IS BASED Under an incentive bonus system, performance (efficiency) and a price per unit of work done are inter-related. It is in the application of this? principle to working conditions .in the Preston East Dome mine that the system to be described differs from the standard methods of calculating mine bonus. It was found that the method of paying a fixed price per unit of work done, under the 'contract' system, gave satisfactory results in development, less satisfactory results in timbering, and results which were not satisfactory in stoping. Under the fixed price system, bonus payments, in timbering and stoping particularly, were very erratic and did not necessarily represent fair payment for the work done. A fixed price in development is satisfactory because the work done, and the conditions under which the work is done, are uniform. The drilling and blasting cycle is completed in one shift, the size of heading is con-trolled, and a minimum number of holes are required in order to obtain a satisfactory break. The performance possible under these conditions has been found to be confined to a fairly narrow range. By performance in development is meant the efficiency of the working crew as expressed in terms of the two variables of feet of advance per round and pounds of ex-plosives consumed per foot of advance. A change in rock formation, how-ever, may alter to a marked degree the performance possible, quite independent of the skill and energy of the working crew. The changes in working conditions that affect development performance from the standpoint of bonus calculation are usually easily apparent and are satisfactorily met by establishing several fixed prices.

Jan 1, 1944

By Y. Huang

Corrosion of GaAs in aqueous electrolytes is a major limitation in implementing GaAs-based photoelectrochemical solar energy conversion systems, In this work, the corrosion behavior was investigated by electrochemical methods and surface analysis approaches, in both H2SO4 and NH3?H2O solutions, Open-circuit measurements showed that the cleaned GaAs surface was very sensitive to water/air, Impedance measurements for n-GaAs showed that an inductive loop only appeared at a high corrosion rate because a reaction intermediate is the oxidant for a further decomposition step in combination with chemical reaction with water, The results suggest that the same corrosion/decomposition mechanism occurred on n-GaAs in the two solutions, When the surface-hole concentration was low, the hole injection or generation process was the rate-determining step, At large reverse bias on n-GaAs, with high-hole concentration, the corrosion rate was limited by a Faradaic adsorption process, involving an adsorbed intermediate, The different surface compositions after corrosion in the two solutions can be explained by the dissolution of As(0), Further oxidation of As(0) to As(III) in NH3?H2O solution is still slow, as suggested from X-ray photoelectron spectroscopy (XPS) analysis,

Jan 1, 2005

By K. Ihara, T. Yamaguchi, K. Matsumoto

"Al-Fe alloy sheets having layers with different strain components were produced by unlubricated hot rolling and the recrystallization texture formation during annealing was investigated in each layer. In this study, the strain component introduced by rolling was quantitatively evaluated by measuring degree of bending of an aluminum pin embedded in the sheet. The textures before and after annealing were investigated by the SEM-EBSD technique. It was clarified that, in the middle layer, where comparatively small shear strain was introduced, ß-fiber subgrains and cube {001}<100> oriented subgrains were formed before annealing, and cube oriented recrystallized grains grew after annealing. On the other hand, in the surface layer, where large additional shear strain was introduced, shear texture components and cube oriented subgrains were formed before annealing, and shear texture was retained even after annealing, while cube oriented subgrains did not grow and were encroached. It was suggested that introduced strain components influenced the recrystallization texture formation by inducing different distribution of the subgrain size, stored strain energy and orientation relationship with surroundings before annealing.INTRODUCTION The microstructure developed during the hot-rolling process of aluminum and aluminum alloys affect the mechanical properties of the final product sheets. Especially, the crystallographic orientation in the final product sheets affects the r- value and ears during deep drawing (Humphreys & Hatherly, 2004), then the texture control in the hot-rolling process is important. When the friction between the rolling roll and rolled sheet in the hot-rolling is large, both the rolling texture and recrystallization texture tend to be heterogeneous in the thickness direction. It is known in many rolled aluminum alloy sheets that the texture in the surface layer was different from that in the middle layer because of additional shear strain. It was reported that in the vicinity of the surface layer, where large additional shear strain was introduced, the shear texture <1 1 1>//ND and < 1 1 0> // RD which contain components of {1 1 1} <1 1 0> and {0 0 1} <1 1 0> developed during rolling, and the shear texture developed even after recrystallization annealing (Sakai et al., 2002). Particularly, it is thought that the <1 1 1> // ND texture contributes to improve the r-value and press formability (Inoue & Takasugi, 2007). Therefore, asymmetrical rolling and high friction rolling have been applied to improve formability of aluminum alloys by adding shear strain in the rolled sheets as deep as possible (Kamijo et al., 1972; Inoue et al., 2005). However, few researches have been focused on the microstructures and texture before annealing and thus, the detailed mechanism is still unclear how the texture after annealing is affected by the texture before annealing. In this study, the Al-Fe alloy of commercially pure aluminum was chosen as the first material to be studied in order to clarify the fundamental process of the recrystallization texture formation. The main purpose of this study is to clarify the effect of additional shear strain on the rolling and recrystallization textures in the hot-rolled sheets by analyzing the transition of microstructure and orientation distribution through recrystallization annealing."

Jan 1, 2018

By Keith Spence

"The notion of ""value"" has always been a subjective and contentious issue. Indeed, Value is in the eye of the beholder. There are varied methods and practices for valuing property, as there are industries in which they are applied. For example, there are ""replacement value"", ""insurance value, ""salvage value"", ""appraised value"", ""book value"" and ""fair market value"", to name a few, although in the mining industry, valuations usually refer to fair market value.In the Canadian mining industry, at present, there are no comprehensive regulations or guidelines that specify which approaches or methods are appropriate for use in the valuation of mineral projects. In January 1999, The Mining Standards Task Force of the Toronto Stock Exchange and the Ontario Securities Commission recommended that the Canadian Institute of Mining, Metallurgy and Petroleum establish a committee to review and advise on approaches and methodologies for the valuation of mineral properties. Among the approaches to be considered, are included the following: the Discounted Cash Flow Approach, the Cost Approach, the Option Pricing Approach and Market Comparables Approach. In addition, methodologies differ depending on whether the project is at the exploration stage or the producing stage.The CIMVal committee expects that its final report will form the basis for a standard Canadian Code for the valuation of mineral properties."

Jan 1, 2003