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By Derek E. McBride

"Exploration work in the Beardmore - Tashota area has led to a reinterpretation of relationships between gold mineralization and the geologicalevolution ofthe area. The host volcanic rocks form two parallel volcanic belts connected by a much smaller cross-cutting band, which trends northeast from Beardmore to Tashota. This connecting band consists of mafic and felsic volcanic, plus clastic sedimentary rocks in a sequence conformable with the contact of the Onaman Lake Batholith to the east. A metamorphic aureole or incorporated xenoliths are lacking along this major contact and the only intrusive relationship observed is chilling between mafic dikes and a cold host granite in proximity to it. Granite dikes are totally lacking in the volcanic succession, or the overlying sedimentary sequence. A major part of this sequence consists of a polymict basal conglomerate with granite boulders and volcanic clasts in a fine-grained chloritic matrix. The nearest source for these boulders is the Onaman Lake batholith.Gold mineralization in significant economic quantities (+ 50 000 ounces) occurs at the top or above the mafic volcanic succession as quartz bands. In the Northern Empire Mine, the band is conformable, folded, boudinaged and the mineral zoning shows a relationship to variations in the host rock, not structural overprinting. In general, where the host mafic tuff is medium-grained, the quartz band is thicker, up to a metre wide, and carries economic grade; where the tuff is finer-grained and bedded, the band is very thin and low grade.Stratigraphic control and metal zoning shows that the mineralization formed as part of the development of the volcano- sedimentary succession. The other major deposits in the area (Leitch and Sturgeon River) have a similar structural history suggesting that they are also syngenetic in terms of the stratigraphic development. Regionally, these deposits were emplaced prior to any significant tectonic deformation but at the end of the mafic volcanic event.The mafic activity was related 10 a period ofextension which caused the volcanic troughs to develop along centres of rifting. The hiatus at the end of this event permitted extensive hydrothermal systems to form and deposit siliceous exhalite bands within sedimentary or terminal mafic volcanic environments in promixity to major thermal sources. Subsequently, the Kenoran Orogeny deformed the entire succession into upright folds with a sub-vertical schistosity. Evidence shows that the deposits have remained intact since deposition."

Jan 1, 1987

By R. A. Horn, S. M. Telfer

"Canada has a per capita GDP second only to Japan among the G7 countries and a positive trade balance which ranks third among the world's major economies. International trade represents a very large part of the national economy and as a proportion of GDP is larger than that of all the other G7 countries with the exception of Germany. On the negative side the Canadian current account deficit relative to the size of the economy is significantly worse than that of all major industrial countries, due mainly to the cost of servicing an immense foreign debt and to a large and worsening negative trade balance in manufacturing.The outflow of money may be reduced by increasing the productivity and competitiveness of those sectors of the economy in which Canada already has a leading competitive position and which have the potential for further growth. The mining industry is uniquely qualified in this respect in that Canada is the western world's largest producer of metals and mineral products and has the geology and the exploration skill to replenish reserves assuming that an adequate level of investment is maintained. In 1989 the minerals industry contributed $8 billion to the country's balance of payments and with the exception of forestry is the only sector of the economy which has shown consistently increasing foreign earnings over the long term.In recent years there has been a decline in exploration in Canada and a significant increase in countries such as Chile. The demand for hard currency to finance the development of the newly emerging capitalist economies of the CIS and Eastern Europe is also driving these countries to seek foreign investment to allow them to exploit their natural wealth more efficiently. Canada is therefore facing growing international competition for risk capital and in the future its trade surplus will probably decline in the face of lower cost foreign production.Canada rightly exercises a high level of environmental control on its mining operations; however a significant deterrent to investment is the fundamentally unjust application of the many provincial and federal environmental laws, under which a mining company, even if it takes every measure to protect the environment, runs the risk of eternal and unlimited future liability. If this situation is not rectified the effect will be an increase in global pollution as mines in countries with more lax application of law and regulations controlling environmental damage replace those of Canada. Tax benefits and incentives are a more efficient means than arbitrary regulations in minimizing environmental damage."

Jan 1, 1994

By Robert Dickson

Princess colliery is operated by Old Sydney Collieries, Limited, a direct descendant of the General Mining Association of London, England, which, in the first quarter of the nineteenth century, pioneered in coal mining in Nova Scotia. The coal worked is a 5 ft. 6 in. seam known generally through the Sydney coalfield as the Harbour seam but referred to locally as the Sydney Main. Entry is made by shafts, 680 feet deep, sunk in 1871 on a headland forming the northern entrance to Sydney harbour. From them extend the main roadways of the colliery, a distance of 700 feet to the shore line and a further distance of 14,700 feet in submarine areas to a total length of 15,400 feet. It was the first colliery in Nova Scotia designed to work submarine areas. Lateral development extends across a frontage of 16,000 feet and the submarine area from which the coal has been extracted is slightly over 6 square miles. There yet remains sufficient territory ahead of the workings to assure a future life to this colliery estimated at over 80 years at the current rate of production. In this area the seam dips at 6 to 7 per cent and face workings have reached a depth of 1,690 feet below the sea level. Until 1923 extraction of the coal was by room-and-pillar, followed by the drawing of the pillars. At that date the superincumbent strata had reached a thickness of 1,400 feet, resulting in heavy weighting on the roof and severe side pressure on the coal ribs. In combination with a soft, heaving pavement this created a set of conditions involving great difficulties and expense in keeping open places driven in the solid sufficiently long to permit recovery of the coal in the pillars by methods and equipment then available. The operator was forced to resort to extraction by longwall as the only economical method of winning the coal.

Jan 1, 1948

By A. H. Onur

Spontaneous combustion of coal is a significant hazard in underground coal mines. It causes serious problems for miners for many years after the fact. It threatens workers? lives and causes economic losses for companies. It disrupts coal production and makes it necessary to abandon the main drift where the spontaneous combustion occurred. Coal fires have to be prevented before they occur; otherwise they are very hard to control. Precautions thus have to be taken in potentially risky areas. For coal to spontaneously combust, it needs 3 elements: fuel, oxygen and heat. If one of them is missing, the fire cannot occur. The best way to prevent spontaneous combustion is to prevent contact between coal and air. Coating of the coal surface with an air-proof lining material would be a practical and useful solution to prevent spontaneous combustion of coal. In the scope of this study, a lining material for coating the coal surface was designed at laboratory conditions. Lining material to be used for preventing coal fires should be airproof, cheap, sufficiently strong, have low rebound, be water- and heat-resistant, and easily obtained and applied. It should also be safe for human health when in contact with mine ventilation. By considering these obligations, 3 kinds of gypsum (plaster, satin plaster, molding plaster), as well as lime, cement and fly ash and different mixtures of these materials were applied in laboratory conditions to form a lining material. Samples of lining material were subjected to uniaxial compressive strength tests to determine their behavior against roof loads. Although there is no need to carry any roof load, the lining material has to be sufficiently strong to stay in place on the applied surface. If the lining material is broken, coal and oxygen can react again. Air permeability and curing time of the mixtures were also tested in laboratory conditions. Then the tested mixtures were applied on a wall with a pump to test the applicability of mixtures. After all tests were performed in laboratory, the most suitable mixture was determined as the optimal lining material to prevent coal fires.

Aug 1, 2013

By P. H. Willis

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

Jan 1, 2000

The Carboniferous sedimentary rocks of southwestern Newfoundland merit investigation because of petroleum, salt and gypsum possibilities and indications of base metallization along the equivalent of the Horton-Windsor con-tact. In this paper, Lower Mississippian (Anguille) strata are divided into three formations: (1) the Cape John below, (2) the Snakes Bight and (3) the Seacliffs. A correlation between these formations and the Craignish, Strathlorne and Ainslie formations of the Horton group? in western Cape Breton Island is suggested. The criteria for the Anguille subdivision are essentially lithological, but preliminary study of included spore assemblages suggests more precise interformational correlations between Anguille and Horton sequences. The re-measured lower portion of the type section of the Codroy group is presented to define more clearly the stratigraphic position of numerous gypsum and limestone beds. Because of rapid facies changes within the Codroy group a simplified two-fold division into upper and lower units is proposed on the grounds of

Jan 1, 1964

By D. B. Dreisinger, M. R. Tavakoli

"Vanadium has been produced from a variety of sources. This metal is known to make aqueous solutions of complex speciation as a function of vanadium concentration and pH. Considering the method of leaching, the impurities in the pregnant leach solution, and the planned vanadium product, different extractants and flowsheets can be applied for solution purification. This paper reviews the purification of vanadium leaching solution using organophosphorus, solvating, and amine extractants. This review focuses on vanadium separation from iron, molybdenum, and uranium, which are often present in vanadium resources such as primary ores, fly ashes, and spent catalysts.RÉSUMÉ Le vanadium est produit à partir de diverses sources. Ce métal est connu pour permettre des solutions aqueuses de spéciations complexes en fonction de la concentration du vanadium et du pH. En tenant compte de la méthode de lixiviation, des impuretés dans la solution mère de lixiviation et du produit de vanadium planifié, divers agents d’extraction et schémas de traitement peuvent être mis en oeuvre pour purifier la solution. Le présent article étudie la purification de la solution de lixiviation du vanadium au moyen d’extractants organophosphorés, solvants et aminés. L’étude cible la séparation du vanadium du fer, du molybdène et de l’uranium, lesquels sont souvent présents dans les ressources de vanadium telles que les minerais primaires, les cendres volantes et les catalyseurs usés."

Jan 1, 2016

By J. Doucet, C. Price

In an industrial setting, operational changes are continually introduced, driven by new technologies or changing economics. Because of day-to-day variability, quantifying the impact of these changes based on metallurgical performance requires long trial periods to achieve statistically significant results. Tools and techniques developed by the mineral processing group at McGill University have allowed for direct measurement of process variables (e.g., bubble size, gas and solid holdup). Two case studies are described where direct measurement techniques were used to evaluate: a) a new rotor stator mechanism; and b ), the introduction of a new frother type. Application of these methods has accelerated the evaluation of process changes and improved confidence in results.

Jan 1, 2009

By F. J. Alcock

The Appalachian region of Canada comprises the three maritime provinces; Nova Scotia; New Brunswick; and Prince Edward Island; and that; part of the Province of Quebec lying south and east of Logan's fault. This; major thrust runs in a gently curving line from lake Champlain to Quebec; city and thence down the valley of the St. Lawrence to pass between Anticosti; island and Gaspe peninsula. To the northwest lies the St. Lawrence; Lowland division of the Interior Plains geological province; a region underlain; largely by early Palxozoic strata; which for the most part lie horizontal; or with low dips; where faults occur they are predominantly of the normal; type; and only locally are the beds cut by intrusive rocks. To the southeast; on the other side of the fault zone; an entirely different set of conditions is; encountered. There; Lower Devonian and older strata stand at high angles; are sheared and thrust faulted; and are intruded in many places by granitic; igneous bodies. The present paper is designed to outline briefly the geological; and structural history of this geological province and to emphasize; the part that structural conditions have played in connection with mineral; deposition.

Jan 1, 1954

By H. R. Butler, R. N. Browne

"The International Nickel Company of Canada Limited consumes some 33 ½ millions of gallons of fresh water and reuses more than 100 millions of gallons of water daily. The continuing search for suitable recycle methodology has enabled the Company to put one 25,000 TPD mill on line utilizing recycled water entirely and a second 35,000 TPD mill is under construction which will likewise employ the concept of recycled water. Future milling plans are aimed at the replacement of all fresh water with recycled water, including sewage effluent and mine waste water.WATER REUSE AT INCO’s SUDBURY MILLSAs man searches unexplored horizons for new and economic industry, he must be constantly and acutely aware of the presence or absence of that precious commodity without which Industry, indeed Man himself, could not survive -- W A T E R. The water requirements of the world today are magnanimous, considering that in 1960 the estimated consumption in the United States was over 300 billion GPD (l) or more than 1,700 GPD per person(5) The magnitude of the problem can be visualized as one considers that three times this quantity of water will be required in the United States by the year 2000, when the dependable supplies of water are estimated to be only two-thirds of that required(2). How, then can we continue to wreak such havoc on that life-sustaining substance - WATER?"

Jan 1, 1970

By J. S. Brock

Magnetic, electromagnetic and gravimetric surveys have played an important role in the mineral exploration leading to the discovery of three major massive sulphide deposits in the Anvil-Vangorda area of the Yukon Territory. During 1964 and 1965 a saturation prospecting program, relying heavily on the integrated use of airborne and ground geophysical survey techniques, led to the discovery of the Faro deposit, which was subsequently proven to be a 63-millionton lead-zinc orebody. Locating the Faro deposit, the largest found to date in this overburden-covered region, involved an exploration sequence requiring the selection of a favourable geologic environment, aeromagnetic and electromagnetic surveys, property acquisition of anomalous areas and detailed ground geophysical surveys, followed by rotary drill testing, detailed gravimetric surveys and diamond core drilling.

Jan 1, 1973

The dissolution of chalcopyrite has received a significant amount of attention. The predominant paradigm of investigation is that its rate of dissolution is limited or passivated by a surface coating or film of material. The common candidates for such a passivating coating are numerous: polysulfide coating, metal deficient layers, copper sulfide coating, bornite layers, jarosite precipitates, and elemental sulfur films. While this line of explanation, that is, the explanation based on passivation, seems to have won some form of consensus with researchers, there is another explanation for the results that can account for all the results observed. Crundwell (1988) proposed that the solid state properties of chalcopyrite, in particular, the semiconducting properties, are responsible for the observed behaviour of chalcopyrite. The purpose of this paper is to outline the semiconductor mechanism of dissolution, and to show how this mechanism accounts for all the observed phenomena recently reported in the literature. The paper outlines the semiconductor mechanism of dissolution, shows how this mechanism accounts for the dissolution

Jan 1, 2014

By G. F. Raymond, W. P. Armstrong

"At the time of this study, the Valley mine was producing 23 000 tonnes of ore per day from a large, low-grade porphyry copper orebody. Sulphide mineralization, principally bornite and chalcopyrite, occurs in a stock work of quartz veins in one phase of the Guichon Creek batholith. The property was explored from 1967 to 1982, and was placed in production in 1983.Using a three-parameter lognormal approximation developed by G.F. Raymond at Similkam een and Mount Isa Mines, a geo- statistical conditional probability ore reserve was estimated prior to mining. Comparisons with blasthole kriging and milled ore for the first 17 months of production showed close agreements at all cut-offs between conditional probability estimates and mineable ore. This was not true of either kriging or polygon estimates. An important part of this work was identifying and correcting for bias in both exploration and blasthole samples.IntroductionCominco's Valley lake deposit is a large, low-grade, porphyry copper orebody in the Highland Valley of British Columbia. Total indicated plus inferred ore reserves are 700 M tonnes at ore grade of 0.47070 Cu. At the time of writing, ore milling is at a rate of 23 000 tI d through the old Bethlehem mill. Mining is in 10m horizontal benches using 9.8 m3 shovels and 90 tonne trucks. Since this paper was written, Valley and nearby Lomex have been combined into Highland Valley Copper with a combined oreproduction of about 120 000 tI d.Copper mineralization, principally bornite and chalcopyrite, is regularly distributed throughout the deposit as disseminated low-grade within a granodiorite host rock, and as higher grade veinlets within a stock work of near-vertical quartz veins generally 10 cm or less in width. It is likely that problems with sample variability and sample bias are mainly related to mineralization within quartz veining. Valley geology has been described in detail by Allen and Richardson and by Osatenko and Jones (2). The exploration sampling program and identification of diamond-drill sample bias have been discussed by Armstrong and Newman'»."

Jan 1, 1988

By D. C. Carter

"The Nova Scotia Department of Mines and Energy located a drillhole at Riverside Corner, Hants County, Nova Scotia, to examine the stratigraphy, structure and potash potential of the Kennetcook River gravity low. This evaporite-related gravity anomaly is one of the largest virtually unexplored gravity anomalies in Nova Scotia. The drillhole intersected a structurally complex sequence o flower Windsor Group ('B' Subzone) evaporites. Downhole geophysical wireline logs were used, in conjunction with detailed lithological descriptions, to interpret the structure and stratigraphy of the sequence. Similar application of total gamma ray, density, caliper and neutron-neutron log responses allows stratigraphic correlation of Windsor Group carbonate marker units separated by up to 35 km in Cape Breton. This work confirms the value of downhole geophysical logs as a tool in the exploration of evaporite deposits regardless of the presence or absence of high quality core. INTRODUCTIONThe exploration methodology for evaporite (specifically salt/potash) deposits in eastern Canada (and worldwide) is relatively simple: identify a negative gravity anomaly within a favourable geological setting, Windsor/Cordroy Group sediments in eastern Canada, and drill it (Anderle, 1980). Although this is an obvious oversimplification of the necessary expertise in the planning and complet ion of an exploration program, those familiar with potash exploration drilling can attest to the risks and expense, in terms of time and problems , associated with the location and drilling of diamond-drill wildcat holes. Potash exploration programs in eastern Canada, their results and inherent difficulties, have been documented by Anderle et al. (1979), Cooper (1981), Dekker (1982), Carter and Boehner (1986), Carter (1988) and Carter and Anderle (in prep .).Downhole geophysical wireline logs have become an important tool in the stratigraphic and structural interpretation of evaporite sequences in eastern Canada and, in many cases, represent the only information recovered or the only information available due to the drilling method (rotary) and/or the long term instability of evaporite cores. This paper documents examples of downhole geophysical log responses which, combined with detailed lithological examination of drill core, or in the absence of core, are used in the interpretation of the complex lithology and structure of a deformed evaporite deposit. Geological and geophysical data from the Nova Scotia Department of Mines and Energy (NSDME) Riverside Corner 85-1 drillhole are presented here as a partial case history and prime example of the use of this method to interpret the complex structure of an evaporite deposit. Drilling of NSDME Riverside Comer 85-1 was conducted in late 1985and early 1986by the Department (Carter and Boehner, 1986) under a program to assess the potash potential of selected areas of the province as part of the Canada-Nova Scotia Mineral Development Agreement 1985-89. A reinterpretation of a portion of the available data from two exploration drilling projects on Cape Breton Island in the Canso-Bras d'Or area is also presented (see inset, Fig. I). Several drillholes have intersected the Windsor Group evaporite sequence in these areas and the available geophysical logs are a valuable tool in the interpretation of the structure of the deposits. However, no attempt has been made to present or discuss the detailed geological investigation and comparison of these two deposits. They are presented here as an example of the reinterpretation of existing data and their application to stratigraphic correlation and structural interpretation of complex evaporite deposits. Further work is necessary to document the stratigraphic and structural correlation of these two areas."

Jan 1, 1989

By D. D. Hogarth

"IntroductionThe Hull iron range, comprising the Forsyth, Scott , Baldwin and Lawless properties (Fig. I), is in Gatineau Park, on the outskirt s o f the city of Hull , and about 6 miles (10 kilometres) northwest of the Federal Parliament Buildings.The deposits have been known many years and described numerous times, although the history has been treated lightly in former publications. Total ore shipments have been calculated at 122,700 long tons, of which over 80% were mined before 1900 and 74% in two brief periods: 1870-74 and 1880-82. It is surprising that the period 1870-74 has been overlooked by most authors and 1880-82 ignored altogether. More surprising, the essential data for these two periods are contained in manuscripts of the Robert Bell collection, which must have been available to officers of the Geological Survey o f Canada.The period 1801-1874 ha s already been covered by the writer in ""Pioneer mines”, but much information has come to light since publication. The present paper is therefore based o n new data and a fresh appraisal. However, little additional data were found for the early history (1801-1854) or for the legal cases involving A.H. Baldwin, and these parts were mainly summarized from the relevant sections of the above-mentioned publication.GeologyThe ore deposits are all situated somewhat below the middle of a graphitic, calcitic marble horizon, here folded into a northeast-plunging synform. The Forsyth, Scott and Baldwin deposits are on the south limb of the synform; the Lawless is on the north limb. The marble is underlain by three non-carbonate groups: biotite gneiss with interlayered quartzite (top), granite gneiss and skarn (middle), and biotite-garnet gneiss (bottom). Below these groups is a lower horizon of graphitic, calcitic marble. The whole sequence is Precambrian and has been subjected to high-grade (Grenvillian) metamorphism, but, in the north, is cut by an unmetamorphosed Cambro-Ordovician diabase dyke. For further information, the reader is referred to the summary by Baird."

Jan 1, 1983

By J. E. Armstrong

"IntroductionT'HE PRODUCTION of gravel and sand may be considered to be the major mining operation in the Lower Fraser Valley of British Columbia. At least thirty pits are in operation with a yearly production probably in excess of two million yards and a value in excess of one million five hundred thousand dollars before crushing, washing, and sizing. The value of the finished products would probably be double the above figure.Since 1949, the writer and his co-workers have been engaged in the geological investigation of the Lower Fraser valley and adjoining Coast mountains for the Geological Survey of Canada. The study, which is not yet completed, includes both bed-rock geology and geology of the unconsolidated sediments lying above bed-rock. In a rapidly expanding industrial area, .an advance knowledge of the geology may• greatly aid in future 'planning, and in many cases may .prevent not only the wastage of large sums of money, 'but possible disaster. Some of the present and future applications in which geological information in the Lower Fraser valley should be of value are as follows: the development of domestic, irrigation, industrial, and municipal groundwater supplies; drainage for industrial sites,, roadbeds, and farmlands; flood control along the Fraser river and smaller streams in the area; the location of dam sites, of major tunnels for water supply •and sewage, of road-beds, of foundation sites for large buildings .and other engineering undertakings in which geology may aid; the evaluation of oil and gas •possibilities; the production of building stone; and the production of sand and gravel, the subject with which this paper is primarily concerned."

Jan 1, 1953

By Roland B. Hoag, Roger G. Webber

Sulphate concentration in groundwater is a good measure of the extent of oxidation of sulphides, provided that sulphide minerals are the primary source of the sulphate. A study was conducted near the Eustis Mine in Quebec to determine where and how the sulphate in groundwaters originated. Atmospheric precipitation is the only source of sulphate other than oxidation of sulphides, and in this study area it is equal to 0.01,. millimole per litre. The oxidation of sulphides can be divided into subsurface oxidation (mainly inorganic processes) and surface oxidation (including both organic and inorganic processes) . The maximum sulphate concentration due to subsurface oxidation of sulphides depends on the solubility of 0 2 in water and is 0.25 millimole per litre. Surface oxidation is, therefore, responsible for any amount greater than atmospheric plus subsurface contributions (0.29 millimole per litre). Surface inorganic oxidation occurs in waters with a pH greater than 15 and is controlled by the kinetics of the oxidation processes. Organic (bacterial) surface oxidation is dominant only in acid (pH< 1.5) waters. The bacterial action accelerates the oxidation of sulphides, and large quanttties of sulphate may be introduced into solution.

Jan 1, 1976

By B. Tiryaki, M. Ayhan, O. Z. Hekimoglu

"This paper discusses the aspects of tracking cutters related to the computer-aided design of shearer drums. A comprehensive computer analysis of drum dynamic parameters for multi-tracking tool arrangement is not presently available, as the current computer programs mainly consider the aspects of single tracking. Despite the fact that the single-tracking arrangement is recommended for efficient cutting, some major drum manufacturers have been seen to persistently adhere to multi-tracking, probably due to a lack of information. Further studies in this field are believed to contribute greatly to the current understanding of the computer-aided design of shearer drums.A number of laboratory simulation trials and long-term underground investigations were carried out in detail on tracking cutter arrangement, and an equation required for a computer program was derived. The results obtained from computer assessment of dynamic parameters for drums with multi-tracking arrangement were found to be in accordance with those of the underground trials, indicating the validity of the equations. The procedure adopted for the computer appraisal of the shearer drums designed with a multi-tracking concept, as described in this study, is therefore recommended to be considered in the currently employed computer programs."

Jan 1, 2003

By George E. Cole

Introduction In view of the fact that, during the past year, two Manitoba mines-Flin Fion and Sherritt Gordon-have entered the list of producers and have materially increased that Province&apos;s contribution to the metal production of the Dominion, it would seem appropriate at this time to review the progress of the industry in the Province, with particular reference to the out-standing metal-mining developments of the past decade. That these two mines have been able to continue their operations in spite of the low prices of copper and zinc adds a touch of brightness to the industrial life of the Province. Depression in metal prices is not encouraging to the mining industry, but it does stimulate efficiency in methods and costs of production. As two thriving towns have grown around the two mines, the will of the management to carry-on is of great consequence to Manitoba, this year so hard hit by the .agricultural depression. And, much as it is a pleasant feature in the mining situation that these mines have been able to continue operations, nevertheless it must be noted, in reviewing the mining developments of the past few years in Manitoba, that the Province was fortunate enough to profit by good times, in that an industry was established which gives evidence of permanency. In the metallic field, the section of Manitoba that first received attention from prospectors was the boundary district, west of the Lake of the Woods. Several claims were staked here at the time of the gold boom in the neighbouring Ontario area. But the first real interest in metalliferous deposits dates from the discovery of gold in March, 1911, in quartz veins on the shores of Rice lake, some twenty miles east of lake Winnipeg. Systematic and organized prospecting of the pre-Cambrian areas of the Province may be said to have commenced with that discovery. The first gold discovery in northern Manitoba was made at Wekusko (Herb) lake in 1914. This was followed by the discovery of the Flin Flan and Mandy copper ore-bodies in 1915 on Flin Fion and Schist lakes, respectively.

Jan 1, 1932

By I. R. Jonasson, R. W. Boyle

"Current interest in the distribution of mercury in the natural environment comes from quite different, though not unrelated, sources. Mercury has long been an important metal in many industries and has, therefore, been much sought after by mining interests. The presence of mercury traces in the various media of the natural environment, namely soil, rock, air, water and vegetation, is exploited by geochemists not only to find mercury and polymetallic ore deposits, but also to find most other types of economic metal mineralization. More recently, however, mercury has caught the attention of health authorities and environmental scientists who are becoming increasingly concerned over the hazards of mercury wastes and the danger these present to the environment and to man. It is now apparent that the trace quantities of mercury, considered so important and helpful to exploration geologists, can be concentrated in the biosphere to such levels as to present considerable problems for ecologists. This article summarizes most of the available data on mercury contents in materials of geological interest and presents average normal values for rocks, ores, minerals, soils, sediments, waters and plants. The geoch.emical cycle for mercury in nature is presented and the mechanisms of mercury migration around the cycle are discussed."

Jan 1, 1972