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By C. A. Lorenson

THE Marmoraton mine is located a mile southeast of Marmora, a village in Hastings county, Ontario, 130 miles east from Toronto and 143 miles west of Ottawa. Highway No. 14 from Belleville intersects Highway No. 7 at Marmora and the branch line of the Canadian National railway between Trenton and Bancroft passes through the property just east of the open pit. HISTORY AND GEOLOGY The Marmora orebody appears as the whorls of a thumb print on the aeromagnetic survey map released by the Ontario Department of Min.es early in 1950, the survey of the district having been made in 1948 and 1949, under the joint auspices of the Department of Mines and the Geological Survey of Canada. The 'anomaly' appeared to have interesting possibilities, so Bethlehem representatives carried out a ground survey and began drilling the property in June, 1950. A total of 40 holes, aggregating 37,000 feet, were drilled to delineate the ore-body. The Marmora orebody is a re-placement of Precambrian limesto.ne with zones or bands of magnetite interlaid with metamorpl1ic rocks and cut by later intrusives. The ore and associated Precambrian rocks are overlain by 100 to 150 feet of flat-lying Palaeozoic limestone. It is a low-grade deposit averaging 33 per cent iron and requires concentration to raise it to 65 per cent iron grade.

Jan 1, 1958

By R. J. McLeod

"Grinding at Giant Yellowknife is done in two stages. The first stage consists of two ball mills in closed circuit will: mechanical classifiers, the classifier overflow goes to flotation. The tailings from this flotation circuit are separated into slime and sand portions, the slimes go to an additional flotation circuit while the sand portion goes to the secondary grinding mills.Milltronic automatic sound control units were installed on each of the two primary ball mills and put into operation September 3, 1966. After about two months adjustments to the control units the operators were taken off the grinding circuit on November 1, 1966. The operators duties were taken over by the automatic control units while miscellaneous work was taken over by the helpers in the mill. The labour saving by the installation is approximately $2250.00 per month.After a short period of operation it was apparent there was a slight change in grind. The screen analysis of the primary classifier overflows for the period May to August 1966 averaged 62.23% minus 200 mesh while for the period September to December 1966 averaged 62.0% minus 200 mesh. This is a slight coarsening of the grind. The change in the primary grind has manifested itself also in the screen analysis of the final grind. Before automation the final grind was 80% minus 200 mesh, while after automation it was 7 5% minus 200 mesh. A change of grind was also noted in the flotation concentrates. Before automation the screen analysis of the concentrates was 35% plus 200 mesh and 50% minus 3 25 mesh. A ft er automation it was 35% plus 200 mesh and 47 .5% minus 325 mesh. In other words the grind got coarser or perhaps we should say there was less overgrinding. Another significant change took place in the assays of the slime and sand portion of the primary flotation tailings. It was usual under manual control for the slime portion to assay higher in gold than the sand portion. The reverse is now true."

Jan 1, 1967

By P. L. Li, B. X. Song, C. H. Wang, T. Wang, Z. Hu

"The treatment of an oxidized copper-gold ore by stage cyanide addition was investigated. For cyanidation, free cyanide ion concentration can be an indicator of whether there is copper dissolved in cyanide solution, and maintaining the free cyanide ion concentration lower than 1.0 g/L could be an effective way to prevent copper dissolution and reduce cyanide consumption. For that purpose, stage cyanide addition was introduced to control free cyanide ion concentration within the range from 0.8 to 1.0 g/L. Cyanidation tests results indicate that gold extraction was still acceptable at reduced cyanide consumption with a lower copper extraction. Based on the experimental study, industry application works at Beiya concentrator of Yunnan province, China were successfully conducted. When the raw ore contains 2.95 ppm Au and 0.75% Cu, by stage cyanide addition method, the gold extraction was still 93% at reduced cyanide consumption of 2135 g/t, which was only half of one addition method, and the copper extraction dropped to only 5%, which indicated that dissolution was prevented for almost 75% of the malachites.INTRODUCTIONCyanide with its competency to form a strong complex with gold, is the most preferable lixiviant for gold leaching. However, cyanidation is not inherently a selective process since many other minerals present in the ore are also readily soluble, especially the copper minerals. Muir (2011) reported that every 1% reactive copper present in the ore consumes about 30 kg/t NaCN, which can have detrimental effects on the process efficiency and economics due to high cyanide consumption, reduced gold leach rates and poor gold recovery."

Jan 1, 2016

By R. Hendricks

"IT IS a pleasure for me to appear before yon today and to have this opportunity of reviewing with you recent developments in the world lead and zinc industry. To provide essential background material, I propose reviewing the period from 1950 to the present, a period which has undoubtedly been the most hectic in the long history of the industry.In capsule form, the pattern for this period is one of repeating cycles of boom and recession, of failure through research to develop adequately new markets and new uses for lead and zinc, of surplus production and growing inventories, of price instability, and lastly, of an abdication in some sections of the industry of responsibility for control of its own destiny by turning to governments for support in time of stress. This is not a pretty picture but, as the 1950 decade ends, there are signs of a new maturity and of a growing determination on the part of the industry to put its own house in order.The difficulty suffered by the world's lead and zinc industry in the current decade originated with the support extended to it in 1950 by the U.S. Government at the time of the Korean conflict. Recalling the shortage of base metals in World War II and fearing that the Korean conflict might develop into World War III, the U.S. Government in 1950 adopted a policy to encourage the production of lead and zinc, both domestically and abroad by means of development loans and long-term floor priced purclu.se contracts."

Jan 1, 1960

By R. D. Brown

In the spring of 1977, Revenue Canada announced its intention to proceed in 1978 with a plan to impute a taxable benefit on interest-free and low-interest loans provided to employees. Such loan arrangements are often an important aspect of the compensation packages provided by many companies to their employees. Since the original announcement, there have been many submissions to Revenue Canada opposing this change, and the Finance Minister has now brought down a compromise solution with the introduction of a proposed amendment to the Income Tax Act. The amendment, which would not take effect until the 1979 taxation year, would require an employee, a shareholder or a related person to include a benefit in income measured as the difference between the interest on any such loan computed at bank prime rate and any interest actually paid. Only the amount of such a benefit in excess of $500 in a particular year would be required to be included in income. Of particular interest is the exclusion from these benefit rules of loans up to $50,000 in respect of the purchase of a house on the relocation of an employee and loans provided for the purchase of shares of an employer corporation.

Jan 1, 1978

By R. J. Mitchell

"High narrow backfills of significant strike length approach the stress conditions associated with a free standing wall but this lower bound design approach is not considered efficient for earth structures. This paper considers the design of high narrow backfills using upper bound limit analysis, retaining wall theory with backfill arching and centrifuge model tests. Complex toe support situations pertaining to operational factors at Falconbridge's Lockerby Mine are investigated. It is shown that the susceptibility of high narrow fills to toppling is much lower than anticipated from the retaining wall analysis and that toppling can be avoided by a suitable toe support. It is also concluded that adhesion between the fill and an adjacent pillar can markedly increase the stability of the fill. INTRODUCTIONFalconbridge's Lockerby Mine pillar projects will expose cemented tailings backfills to heights (H) up to 55 m. The exposed backfills may have strike lengths (L) greater than the heights but are relatively narrow, having widths (w) of up to 12 m. The bulk cement content of the fills varies from 8.3% (12.1 T:C) to 3.0% (33.1 T:C). Exposed faces may have up to a metre of overhang due to stope overblasting, as shown in Figure 1. These fills have a solids specific gravity of close to 3.0 and were placed at a pulp density of about 68%. The tailings have a fairly uniform grain size with 32% less than 0.075 mm (200 sieve) and about 12% slimes (less than 0.02 mm sizes). The fill exposed by early pillar removal will be backed by adjacent, near vertical, ore pillars. Future pillar removal may expose similar fills which are not supported by an adjacent ore pillar but which will be backed by either an open void or by uncemented backfill. Furthermore, these fills may be undercut when the pillar slot is driven, further reducing stability (case 3, Fig. I) or a wedge could be left to help support the fill (case 2, Fig . 1). This paper presents limit equilibrium analyses for these various backfill conditions in a 22: 1 T:C fill and com- pares the results to data from centrifuge model studies at a scale factor of A= 157 as indicated in Figure I. Prototype fills have a 6 m deep cone plug of 16:1 T:C which is accounted for in the comparison of centrifuge model test with analytical results."

Jan 1, 1989

By Serge Ouellet

Résumé Six modèles métriques de remblai cimenté en pâte (RCP) ont été suivis durant 120 jours par l?utilisation de deux méthodes géophysiques non-destructives : la résistivité et la micro-sismique. Les RCP étaient constitués de trois résidus miniers et de deux proportions de ciment (3% et 6% en poids). En parallèle, des cylindres de RCP étaient utilisés pour évaluer périodiquement l?UCS. La résistivité augmentait quasi-linéairement de 28 à 120 jours pour tous les RCP investigués. Des variations de résistivité selon le type de résidu et le pourcentage de ciment ont été observées. Une équation empirique a été dégagée entre l?UCS, la résistivité, le temps, la densité relative et le rapport eau/ciment (E/C). La mesure de la vitesse des ondes de cisaillement a permis de dégager une équation mathématique de type exponentielle qui relie la résistance mécanique sans correction préalable par les paramètres de la recette de RCP. La réalisation de ce projet avait pour but de dégager la meilleure approche non-destructive afin d?estimer la résistance mécanique des remblais en chantier minier. Sur la base des résultats obtenus, les deux méthodes utilisées ont donné des résultats probants afin d?estimer la résistance mécanique et les deux méthodes sont donc à même d?être utilisées en chantier souterrain. Abstract Six scale models of cemented paste backfill (CPB) were followed during a 120 days period using two nondestructive geophysical methods: resistivity and micro-seismic. CPB were made up of three mine tailings and two cement proportion (3% and 6% by weight). In parallel, CPB cylinders were used to periodically evaluate uniaxial compressive strength (UCS). Resistivity was increasing nearly in straight line from day 28 to day 120 for all CPB models. According to the tailing type and cement percentage, resistivity variations were observed. An empirical equation emerged from UCS, resistivity, time, specific gravity of tailings and, water/cement ratio. The use of shearwave velocity allowed to identify a mathematical exponential equation related to mechanical strength without prior correction of the CPB?s formula parameters. The purpose of this project was to identify the best non-destructive approach in order to evaluate the mechanical strength of backfill in a mine site. On the basis of those results, both methods gave conclusive results in order to estimate mechanical strength and both methods can be used in underground operations.

Feb 1, 2008

By A. G. Roach

Introduction This paper deals with the operations and plant of the Craigmont Corundum Project, formerly of Wartime Metals Corporation but now under the Mines Section of the Resources Development Branch of the Department of Reconstruction and Supply. Corundum is recovered by the re-treatment of an old tailing deposit at Craigmont, Ontario. Crude concentrates so produced are shipped to the plant of the American Abrasives Company, Inc., at Westfield, Mass., for final processing and distribution to the abrasive industry. The plant was recently described in a paper entitled Craigmont Corundum which was presented by the writer before the Chicago meeting of the A.I .M.E. in February, 1946. General The Project is located on? lots 4 and 5, concession XVIII, township of Raglan, Renfrew county, Ontario, near the village of Combermere, which is on Highway 62. The property is about 135 miles from Ottawa. The general area enjoys a pleasant climate with moderate summer temperatures, though the winters are rather severe, the mercury frequently falling to - 35 deg. F. The excellent boating, fishing, and hunting have made the district a favourite resort for tourists. Lumbering is the main industry. Some farming is carried on, but the soil is poor and much of the land is hilly and rocky. There are no other operating mines in the immediate vicinity, though several 'industrial minerals', including mica, feldspar, nepheline, beryl, socialite, and others have been produced in the area. The district is drained by the York and Madawaska rivers and is generously dotted with large and small lakes. The general elevation is about 1,000 feet above sea level, though numerous hills rising several hundred feet give a rolling appearance to the landscape.

Jan 1, 1946

By J. B. Sabey, V. R. Degner, D. MacGillivray

"Hydrodynamics principals are applied to the design of a natural air ingestion flotation machine for coarse solids applications. Preliminary laboratory test data and subsequent operating plant flotation kinetic performance evaluations are reviewed. INTRODUCTIONThe concentration of potash (sylvite, KCI) from halite and other salts using flotation is well understood and practice a with much success. Reagent schemes and plant circuitry for obtaining the desired product recovery and grade have been established with proven performance. These flotation circuits normally process the medium and finer size particles, less than 30 mesh (600 microns).However, often the potash market trends specifically demand a coarse product size. This emphasis, accompanied by the existing high losses of coarse (+30 mesh) potash in flotation circuits, creates the need for development of a flotation machines specifically designed for coarse potash beneficiation.This technical challenge was undertaken by the WEMCO Research and Development Group. The specific objectives of this flotation machine development program were ( l) to achieve an ""Ultra Coarse Flotation Machine"" capable of adequately suspending and transporting particles in the 4 - 30 mesh (4.75 - 0.6 mm) size range at solids concentrations of 30% or greater and (2) ascertain metallurgical performance of this machine.This paper covers the development (both theoretical and mechanical/ hydrodynamic), the field test program and results, a discussion of applicable flotation kinetics, and conclusions of this ""Coarse Potash Flotation Machine"" development project."

Jan 1, 1986

By J. U. MacEwan

THE basis on which the modern metallurgical industry is operated is the endeavour to attain maximum return in purchasing power for the least expenditure of energy. This has always been the general objective of the industry, as of all industries. In recent years, however, it has received a new emphasis. Today, as never before, increased attention is being directed to the detailed study of plant operations and the application of scientific knowledge and of business principles in order to achieve the maximum efficiency. This new emphasis is the result in large part of the new problems and conditions with which the industry has been confronted, chief among which are the following: (l) Development of new ore-bodies and the treatment of complex ores. (2) Necessity of achieving a greater degree of purity in some of the metals in order to meet the newly discovered demands for some of the industrial metals. (3) Discovery of new markets for many of the metals, either in pure form or in the form of alloys. ( 4) Change in values, absolute or relative, of some of the important metals. (5) Increasing scale of investment in expensive plant and equipment, which makes imperative most efficient utilization if total unit costs are to be kept to a minimum. (6) Increasing scale of operations in some important branches of the industry, which also makes essential maximum efficiency in organization, administration, and operation. The success with which the metallurgical industry has met the problems created by these changing conditions has been due primarily to the following factors: (1) Results of research and experimental work carried on by universities, government laboratories, and many private corporations in the industry itself. (2) Closet study of every detail of plant operation, both from the technological and from the economic point of view, with the object of increasing plant efficiency. (3) Interchange of information and experience amongst the operating companies. It is only by the concerted efforts of numerous investigators and experimenters that the underlying fundamentals of plant operations can be learned. The exchange of results permits their easy assembly and correlation with maximum benefit to the whole industry. Unnecessary duplication of research and experimental work is avoided and the industry as a whole is able to reap the fruits of this work with the maximum of-speed and efficiency. (4) Advances made in recent years in so-called 'scientific management' in industry as a whole and the application of the principles learned to the metallurgical industry. A review of the modern trends in extractive non-ferrous metallurgical processes illustrates the afore-mentioned new conditions and problems, and gives some idea of the methods by which they have been and are being surmounted.

Jan 1, 1937

By Charles A. Taschereau

Burkina Faso ? Formerly known as Upper Volta; Country is landlocked and dry (Sahel sub-Sahara zone); ? Among poorest countries in the World, according to the United Nations Human Development Index (in 2005, 178 out of 179 countries; in 2009 173 out of 179); ? Population 13,9 Millions; Life expectancy is 51.4 years; Fertility rate 6.47 children/woman; Average age is16 years; literacy rate 23.6% and GDP per capita $1,213; ? French is official language; Politically stable country; very low criminality rate; corruption level low. Multiparty elections since early 90s; Legal and political systembased on French civil law system; ? Country just opened a few years ago to International mining companies, with a new mining code and investment code; ? No experienced labour; ? All new codes and laws; no established practices; Very limited economic development, mining is already main product of exportation and the country will become with Essakane a mineral economy (over 50% of total exports from mineral sources);

May 1, 2010

By W. G. Spencer, E. Sulis, P. M. Tiley

"Dome Mine's No.8 shaft is located about 1 km northeast of Dome's No.3 shaft and mill complex in South Porcupine, Ontario.No.8 shaft was brought into production in 1984 to hoist ore and waste for the complete mine as well as to service the mine from the 1600 level and below. Access above 1600 level is provided by No. 3 shaft.The rectangular shaft has six compartments consisting of two skips, a cage, counterweight, manway, and a service compartment. The over-all size of the shaft is 14 ft 7 in. by 20 ft by 7 in. (Fig. 1). A 7th compartment for shaft deepening is incorporated in the bottom 500 ft of shaft. The shaft is 5470 ft deep. The loading pocket is located at 5300 ft and the dump 61 ft below the collar.Surface facilities consist of a concrete headframe and a structural steel hoistroom which houses the cage and production hoists . The service hoist is a 12-ft diameter double drum, with one 1750 HP DC motor, and the production hoist is a 15-ft diameter double drum with twin 1750 HP DC motors.Both hoists have a single clutch and a single reduction gear train built by Orenstein & Koppel, and equipped with Canadian General Electric drives. The cage hoist is equipped with a disc pinion brake.The skips were originally aluminum 14-ton capacity, Rolla-chute design with steel liners on three sides and 4 in. of rubber on the back, to absorb the loading impact. The original guide rollers consisted of fixed 10 in. pneumatic tires. The face-to-face units were eventually replaced with larger airplane-type tires mounted on a spring loaded pivot arm."

Jan 1, 1993

By Weiren Lin

The Mw 9.0 Tohoku-Oki, Japan earthquake occurred on 11 March 2011 produced a maximum coseismic slip of >50 m near the Japan Trench. To investigate why the plate boundary fault between the subducting Pacific Plate and overriding North American Plate which caused the earthquake had such unprecedented large coseismic displacement and slipped to the trench, Integrated Ocean Drilling Program Expedition 343 called Japan Trench Fast Drilling Project (JFAST) drilled three boreholes at Site C0019 through the earthquake fault about one year after the earthquake. Borehole C0019B dedicated to loggingwhile- drilling (LWD) penetrated ~850 meters below seafloor (mbsf) at a water depth of approximately 6890 m. The plate boundary fault is located at ~820 mbsf in the borehole and has been identified as the slip zone during the Tohoku-Oki earthquake. Borehole wall resistivity images obtained from LWD show that drilling induced borehole breakouts are available in a wide depth range above the fault but are not available below the fault. Breakouts are reliable indicators of the orientations of current maximum and minimum horizontal stresses and can also be used to constrain the horizontal maximum and minimum stress magnitudes. As results of breakout analyses, the maximum horizontal stress orientation highly varied in the upper part of the borehole, but has a clear preferred orientation in a northwest – southeast direction in the deeper part just above the fault. This orientation is approximately parallel to the direction of the Pacific Plate subduction. Stress magnitude constraints indicate that the post-earthquake stress states in the hanging wall are either in or close to the normal faulting stress regime. By inferring the pre-earthquake stress state and comparing with the constrained post-earthquake stress state, a significant coseismic stress change was interpreted. The stress change suggests an active slip of the frontal plate-interface consistent with coseismic fault weakening and a nearly total stress drop.

Jan 1, 2015

By M. D. Everell

Le Centre de Recherches minérales (CRM), qui est un organisme de recherche appliquée du ministère de l'Energie et des Ressources du Québec, a été créé en 1969, dans le but de procurer un support scientifique et technique à l'industrie dans le domaine des mines et de la métallurgie. Pour atteindre ses objectifs, le CRM met à la disposition de l'industrie un personnel spécialisé et compétent dont une quarantaine d'ingénieurs et de scientifiques. Etant donné la nature même de l'industrie minérale, ce personnel est très versé dans l'étude des problèmes diversifiés des domaines de la technologie minière, du traitement des minerais, de la métallurgie extractive et de l'analyse minérale. Ce Centre de recherches met également à la disposition de l'industrie une usine-pilote permettant de reproduire les résultats du laboratoire au moyen d'un appareillage de type industriel, d'obtenir des échantillons en quantité suffisante pour une exploration du marché et de familiariser du personnel avec les opérations normales de l'industrie. Certaines de ses contributions récentes au développement de l'industrie minérale du Québec seront présentées.

Jan 1, 1985

By D. K. Storer, W. Lee, S. Tkach

"A microcomputer-controlled multi-probe K-40 monitoring system was developed internally for the Phase II mill at the Lanigan potash mine. The K-40 probes were mounted in a variety of positions in several process streams, ranging from dry ore on a conveyor belt to brines and slurries. A description will be presented of the objectives, the equipment and the difficulties encountered in correlating results.IntroductionThe successful control and optimization of most metallurgical processes involves monitoring not only physical parameters such as flow rate and temperature, but also the chemical compositions of critical streams. Composition has proven difficult to measure on -line in industrial scale processes. However, in potash processing there is a convenient chemical parameter that has long been utilized to measure in situ the concentration of potassium chloride (KCl). Potassium has a long-lived isotope which is slightly radioactive. K40 decays by beta elimination to Ca40, ultimately radiating a characteristic gamma-ray photon. This gamma emission when detected by scintillation counter can be used to estimate the concentration of potassium in a process stream."

Jan 1, 1990

By W. C. Whittaker

Introduction When one thinks of a coal stripping deposit, the picture that usually comes to mind is that of a more or less flat seam from two to twenty feet in thickness overlain by ten to fifty feet of overburden, in suitable ratio for economic operation. This is the usual type of stripping deposit and is quite a common occurrence in various parts of the prairie provinces. Rather unusual types of coal stripping deposits are being presently worked as open-cut mines by Sterling Collieries, Limited, and the Co al Valley Mining Company, Limited, at Miles 47 and 48 on the Alberta Coal Branch, some 150 miles south west of Edmonton. These deposits are of interest chiefly because they represent turned-up and greatly thickened sections of the Mynheer seam, and as such they present their own problems, peculiar to the commercial exploitation of a seam of this type. The area in which these deposits occur was originally owned by the Pacific Pass Collieries, whose operations, however, were confined to under-ground mining at Lovett, some eight miles to the southeast. It was not until l918 that the value of these deposits was realized, when the Company now known as Sterling Collieries, Limited, opened their pit at Mile 47. At the inception of the work, coal was loaded directly into the railway cars by men using wheelbarrows. In 1920, a tipple was built, after which the coal was loaded by steam shovel into mine cars, hauled by steam dinkeys, and loaded over the tipple into railway cars. In 1922, the Coal Valley Mining Company entered the field at Mile 48, with an entirely mechanical equipment, and at the present rime these two are the only stripping properties in Alberta using mechanical equipment both for the removal of overburden and the loading of the coal. These Companies have operated continuously since that time, and have to date mined and shipped 4,000,000 tons of coal, and moved some 5,255,000 cubic yards of stripping. The present annual coal output for the two mines is about 240,000 tons.

Jan 1, 1935

By Barry D. Simmons

"A well-defined approach is essential to ensure the long-term success of a regional exploration program. Teck's approach in eastern Canada is designed to fulfill corporate objectives while recognizing certain unique parameters for exploration in the area. The elements of this approach include clearly defined objectives, technical considerations and personnel policies, all of which are equally important. The goal is a significant discovery before the mid-l990s and the company is confident that this target will be achieved.IntroductionAs one of Canada's oldest continuously operating mining companies, Teck Corporation traces its roots to Kirkland Lake, Ontario, with the development of the Teck-Hughes gold mine in 1913, later supplemented by production from the Lamaque gold mine in Val d'Or, Quebec. Control of the company was acquired by Temagami Mining Company, part of the Keevil Mining Group, in 1959. Credited as one of the first discoveries made using airborne geophysics, the Keevil Group had recently found the small but very high-grade copper deposits at Temagami, Ontario. These developments in eastern Canada formed a foundation for remarkable growth and Teck's present status as one of Canada's most successful and respected mining companies.Teck currently operates successful mining ventures across Canada and has international exposure through its association with Cominco Ltd., M.I.M. Holdings Limited and Metallgesellschaft AG. Operations in eastern Canada, however, remain an important component of Teck's ongoing success. The David Bell and Williams mines at Hernlo, Ontario, are Canada's lowest cost and largest gold operations, respectively. The Niobec Mine at Chicoutimi, Quebec, is North America's only significant producer of niobium. Teck maintains a 45070 interest in Golden Knight Resources Inc., part owner of the successful gold mining operation in the Casa Berardi area of northwestern Quebec. As a significant shareholder in Aur Resources Inc. and as a part owner, Teck is participating in the development of the Louvicourt deposit, a major base metal discovery at Val d'Or, Quebec."

Jan 1, 1992

By Richard J. Haslinger, C. Mark Rebagliati, James L. Oliver

Abstract - Exploration at the Specogna gold deposit has identified a geological resource of 65.0 Mt grading 1.63 g/t Au, which equates to 3 million ounces of contained gold. This resource is hosted in a low-sulfidation epithermal deposit of Miocene age that is localized along the northwesterlytrending Sandspit fault. The fault has juxtaposed Late Cretaceous mudstone of the Haida Formation to the west, with Late Tertiary coarse clastic sediments and lesser andesitic volcanic rocks of the Skonun Formation to the east. A plagioclase porphyritic dacite dike intrudes the Haida mudstone and Skonun sediments along the fault. Gold mineralization, in hydrothermal breccias, veins and stockworks developed mainly in Skonun sediments and dacite. These are formed in an 800 m long zone that roughly parallels the Sandspit fault. The gold zone is funnel-shaped in cross-section, approximately 300 m wide at surface, 220 m above sea level, and narrows to approximately 50 m, at sea level. The deposit lies within an elongate zone of moderate to intense hydrothermal alteration that, at surface, extends over a known area of approximately 2 km2. Its western extent is bounded by the Sandspit fault. There is an asymmetric alteration zonation, with a core of silicic-potassic (adularia) and smectite-illite clay alteration that is bounded to the east by argillic alteration. Similar zoning defined by the distribution of metals reflects the position of the main feeder conduit. Mineralization of altered wallrock is dominated by 1% to 4% auriferous pyrite and marcasite. Gold and silver occur as electrum; individual silver minerals have not been identified. Other sulfides are rare, and are identified only microscopically. The mineral suite is typical of low-sulfidation epithermal systems. Gold occurs in early, multi-phase, variably bladed and banded quartz veins and breccias, which are cut by barren, single phase, drusy quartz veins.

Jan 1, 1998

By C. M. Campbell

IN 1934 Newfoundland, after extravagant operation based on exaggerated ideas of what she had to work with, became bankrupt, ceased to be a self-governing Dominion, and passed into the hands of a Commission. Since the days of Dawson, Canadians have been taught that no country in the world is as rich as their own. This idea has become a religion; contrary views are heresy, and are suppressed even by technical organizations and government departments. Following the alleged habit of the ostrich, we have buried our heads in the sand and have refused to face the facts. This policy of "to have today and to hell with tomorrow" is now bearing fruit. After forty years of operation on the basis of unlimited natural wealth, with resulting over-expansion, wholesale depletion of capital assets, and huge borrowings, we are, now that our wealth has been shown to be very limited, face to face with the status of Newfoundland. Already, in this Province, commission government of bankrupt municipalities is not uncommon. The ostrich is referred to as the most foolish bird in the world. That is not the case-no ostrich ever hid his head in the sand. In the clear air of his home on the South African veldt, an area characterized by low bushes, he is a conspicuous object. When danger approaches, he lowers his head; matches his background, the bushes; and danger passes him by. This leaves the Canadian, with his head still in the sand, to fill the r61e cast for the ostrich. Fortunately, a few Canadians never did get their heads covered; others are getting them out far enough to see what is going on. Their comments are very much to the point. "Nowhere in the world," says Mr. Meighen, "has more harm been done to any country by an exaggeration of its resources and potentialities than has been done in Canada'.

Jan 1, 1941

By Morris J. Viljoen, Young. David R.

"Abstract -The zone of economic interest at H.J . Joel Gold Mine is the VS5/Beatrix Composite Reef, a quartz-pebble conglomerate of Archean age. The reef occurs at the base of the Eldorado Formation, Central Rand Group, of the Witwatersrand Supergroup. At !east three stratigraphically distinct conglomerates form this economic zone. In order of deposition these are the Footwall, Beatrix, and the VS5/Beatrix reefs. The Footwall and Beatrix reefs are equated with the Aandenk Formation with transport directions toward the northwest, whereas the VS5/Beatrix Reef is of Eldorado age, with transport directions toward the south. The change in the drainage direction was caused by a major basin-wide tectonic event that occurred prior to the deposition of the Eldorado Formation. The Beatrix Reef was formed in a proximal, braided, fluvial environment by a process of aggrading gravel bars between channelways. The VS5/Beatrix Reef was formed by the desegregation of pre-existing Beatrix Reef with the introduction of new material containing much shale detritus and is seen to have been deposited in a more ·distal, braided, fluvial environment, similar to the Beatrix Reef.The average gold concentrations are different for each conglomerate; the Beatrix at 32.1 ppm Au, the Footwall at 24.4 ppm Au, and the VS5/Beatrix at only 12.4 ppm Au. A sedimentary gold concentrating process related to higher energy braid channels was primarily responsible for these high gold grades. Not only the basal unconformity surface, but also, internal degredation surfaces, were prime sites for concentration. An understanding of the spatial distribution of these differing conglomerates and their braid channels forming the economic reef zone is necessary in predicting ore grades for future mining."

Jan 1, 1994