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By C. P. Jenney

"Exploration for copper, in a region of 7,000 square miles on the Arctic coast between longitudes 114 and 118 degrees west, has covered a period of nearly 200 years. Occurrences of native copper, used by the natives for tools and weapons, have been reported since the early part of the eighteenth century. In J 771 Samuel Hearne of the Hudson's Bay Company, in the course of his classic 3-year journey from Fort Churchill, became the first white man to see the deposits, and incidentally the first to reach the Canadian Arctic coast by land. During the next 140 years the deposits were mentioned by every explorer and traveller who passed through the area. A good historical summary of this literature has been presented by Tyrrell (1912).In 1911-12 the Douglas-Sandberg party did the first geological mapping along the Coppermine River and Dismal Lakes (Douglas, J., 1913; Douglas, G. M., 1914), and described the copper occurrences there. In 1914 J. J. O'Neill (1924) of the Canadian Arctic Expedition investigated the showings on Bathurst Inlet. In 1929-31 two Canadian exploration companies sent prospectors and geologists to the area (Gilbert, 1931; Norrie, 1931; Duncan, 1931). Since that time only brief references have been published (Kidd, 1931; Stockwell and Kidd, 1931; Lord, 1941, 1951; Washburn, 1947). In 1943-45 an area of more than 1,500 square miles was prospected by American Metal Co. of Canada, Ltd., under the direction of the writer. Forty-nine showings were examined; seven of these were mapped in detail by plane-table and two were sampled by 27 short diamond drill holes totalling 3,061 feet. All holes were in permanently frozen rock, and the deepest vertical distance reached was 206 feet. Five groups of claims were staked. These later lapsed, but one of the groups was restaked in 1951, and assessment drilling and some trenching were carried out in 1952-53. Results were disappointing, and the claims have been allowed to lapse.The area is within the Arctic Circle, northeast of Great Bear Lake and 360 miles north of Yellowknife on Great Slave Lake. For exploration purposes, access is by aircraft from Yellowknife. During the short open season heavy freight can be brought by sea to Coppermine at the mouth of the river, either from Aklavik at the mouth of the Mackenzie or around Alaska. Concentrates would have to be moved by these routes.Although none of the deposits so far found is mineable under present conditions, the total volume of copper in the numerous showings marks the district as a major area of copper mineralization, which may some day be of economic importance."

Jan 1, 1949

By H. R. Oliveira, C. R. Aragonez de Vasconcellos

Pipeline operation and maintenance necessarily involves geotechnical studies at points and areas with deflagrated instabilities or still to map and monitor areas prone to geotechnical problems. Landslides, erosions and debris flows are some examples of natural hazards, that not rarely, can bring high consequences to pipelines, sometimes leading them to high stresses levels and ruptures. Bolivia-Brazil Natural Gas Pipeline has 2.593 kilometers since Rio Grande City in Bolivia until Canoas City, in south Brazil. The pipeline crosses a lot of types of geological fields and difficult topography. The south spread of the pipeline has the most prone areas to geotechnical hazards because of its hard topography combined with the variety of geological materials, such as, colluvium deposits and debris flow areas. The aim of this paper is to present the right-of-way geotechnical risks that affect pipelines, presenting some practical remedial works done by TBG at Bolivia-Brazil Natural Gas Pipeline as well as the integrity plan and the adopted actions in way to prevent geotechnical accidents.

Jan 1, 2005

By Karl J. C. Harries

"14.1. INTRODUCTION1The boilerplate of an agreement is not a single provision, but a series of provisions that are expected in “every agreement”. They are sometimes also referred to as the “lawyer’s provisions”. Many businessmen consider the boilerplate to be superfluous and, to some extent, window-dressing by the lawyers – even legalese. They will often offer advice to the effect that it can “pretty well be ignored”. Such advice could not be more wrong.Most boilerplate provisions are essential parts of every agreement. Some may be part of a “standard package” and may have little relevance to the agreement at hand, but these are the exception rather than the rule. The exceptions should not be treated as justification for giving all these provisions short shrift. The boilerplate should receive the same review, consideration, and negotiation as the provisions that set forth the business deal. It is often these provisions that make the deal work or that are turned to at the time of disputes. If they are inadequate, as they sometimes are (unfortunately, some draftsmen are also loath to review or update their standard boilerplate provisions or to tailor them to the deal at hand), they can create problems, rather than offer solutions. Such problems can be costly and time-consuming for the parties to address. Inadequate or incomplete provisions may ultimately be one of the reasons for the parties to turn to the courts to settle their differences. On the other hand, good boilerplate provisions can help keep them out of the courts.One of the principal objectives of an agreement should be to provide procedures, or mechanics, for implementing agreed principles and for the parties to follow to settle their differences, real or perceived, without going to the expense and disruption of a lawsuit. An agreement should aim to keep the parties away from the courts, not serve as a springboard to the courts. It must nevertheless be acknowledged that, if there is a major falling-out among the parties to an agreement, the chances are that, however carefully the provisions of that agreement have been negotiated and drafted, the parties will end up before the courts or some other adjudicating body."

Jan 1, 2003

By Jasmin Raymond

Ground source heat pumps are used to heat or cool building and heat water supply. Such heat pumps use the earth as a heat source or sink to efficiently provide or store thermal energy. For example, a ground source heat pump typically requires less then a third of the electric or fossil fuel energy of a conventional heater. Ground source heat pumps could therefore help reduce the energy consumption of active mines where low-grade geothermal resources are abundant. In most heat pumps, water or a water-antifreeze mixture having a temperature ranging from -6.5 to 43.5 °C is circulated through a heat exchanger at a rate of 0.000033 to 0.000067 m3/s (2 to 4 L/min) for each kilowatt of heating/cooling capacity. The groundwater that is continuously pumped to drain mines could be used to operate heat pumps. Water feeding a heat pump can alternatively circulate in a close loop network of pipes buried underground or installed in a surface water body. Retention water ponds, tailings and waste dumps commonly found at active mine sites could provide excellent environments to install the close loop system. Further research will help take advantage of the unexploited geothermal resources associated with actives mines.

May 1, 2007

By T. A. Rickard

FROM AN OLD MANUSCRIPT THE text for this contribution to the history of the Patio process is a page taken from a Spanish manuscript of Bartholomé Arzaj Sanches y Uela, now in the possession of the library of Brown University (see Figure 1). I owe the photographic print to the courtesy of the librarian. The date, as will be seen, is 1577. The subject is the treatment of silver ores at Potosi, in old Peru, but in modern Bolivia. The group of drawings (see Figure 1) is entitled "Arrangement of the machines in which the ores of silver are ground on the bank of Potosi, the one of two batteries and the other of one". First, top-left, we have the sketch of a "machine of one battery" operated by a water-wheel. From this mill the water runs in part along an aqueduct supported by pillars to the two-battery mill and in part down the hillside, where men are at work with "tubs, which are called cochas, in which are washed the charges of ore and amalgam". Along the top of the page are shown the "various offices in which are stored the copper, the salt, the ucha [llama dung, used for fuel], the lime, and other materials for the re-duction of the ores". To the right of these are "apartments and warehouses in which is stored the ore brought down from the mountain"?the cerro de Potosi. Through the arched portal come the "sheep [llamas] on which is brought down the ore". To this is added a reference to "the second gate, which closes the whole works". On the level above the aqueduct are seen six men carrying skin-bags that contain water. This is being sprinkled on the ore. On the extreme right are six more of these water-carriers. Next comes the two-battery mill. The mortero, or mortar, is marked on the right. Another description says, "Stone, on which the stamps crush the ore, which is called a mortar". To the left of these are indicated "screens of wire in which the ore is sifted after it has been crushed". Farther to the left, near the ore-washers, is a "shed, in which is placed the metallurgist to test the ore of the boxes". Along the left side of the page are sundry buildings, one of which is labelled a "shed in which are placed the cones of silver". Near it, lower, to the right, is the "furnace, in which are roasted the sulphides to facilitate treatment". Farther to the right is the "place where the Indians mix the charges of sulphide ore, which is called a buitron". Alongside is a "buitron in which the charges are prepared for reduction". Inside is a container, to which are attached the words "measure, called topo" On the extreme right is "another buitron in which the Indians mix the ores with their feet, as well as the heaps for the preparation of the reduction". Near the bottom, on the extreme left, is the "chapel where the holy sacri¬fice of the mass is celebrated". Under the first buitron is the "place where they dry the moist ores, called pãpear".

Jan 1, 1935

By B. Panton, J. Carvalho, E. T. Brown

"A major consideration in the design of high capacity tiedown anchors for dam, bridge and tower foundations is the tensile resistance of the rock mass to pullout, typically as a result of overturning moments or hydrostatic uplift. Rock mass pullout capacity for installed anchors is developed from the tensile strength and fracture propagation properties of intact rock, the orientation and physical properties of the discontinuities and anchor confinement at depth. The typically assumed, but generally conservative, design approach is to calculate anchor pullout capacity using the dead weight of a uniformly shaped inverted “cone” with an assumed initiation point and breakout angle. In some cases, some tensile or shear strength is considered across the area of the assumed pullout cone, however, these strength estimates are based primarily on based on limited historic testing data, empirical relationships for rock mass strength developed for other applications, and engineering judgement.As an alternative to the current foundation anchor design method, this paper presents a new approach to the rock cone pullout problem using Discrete Fracture Networks (DFN) combined with numerical simulations. The simulations presented in the paper investigate the influence of fractures in a synthetic rock mass on ultimate anchor strength. In addition, the global influence on fracture network statistics on rock mass pullout failure is also discussed and it is contended that some of the aleatory and epistemic uncertainty inherent in the design of rock anchors can be reduced by considering fracture statistics in anchor design."

Jan 1, 2015

By Paul D. Merica

This year of 1926 marks the 40th. anniversary of nickel mining in Canada. Although the first nickel mine of the Sudbury basin was discovered in 1883, it was not until 1886 that the Canadian Copper Company was organized and actually began to mine copper-nickel ore from the Lady McDonald, Stobie and Evans mines. The intervening years have witnessed some exceedingly interesting nickel history, particularly interesting and gratifying as well to Canadians. Forty years ago, at the inception of Canadian nickel mining, the world's consumption of that metal was about 1000 tons per annum and this was supplied largely from New Caledonia ores refined in France. This nickel was used principally for the production of nickel-silver, coinage alloys, and for nickel-plating. No processes were then known for refining the Sudbury ores nor for the separation of copper from nickel. Consequently, the pioneers in Canadian nickel mining faced the double problem of finding a method of treating their ores, and of finding a market for the nickel when and if they could extract it.

Jan 1, 1926

By H. Hitchen

THE object of this paper is to present the various facts that l1ave been revealed during lengthy investigations into the performance of all types of ropes on different hoisting installations. It then goes on to suggest means by which most of these findings could be usefully employed to obtain more economical rope lives with increased safety. SHAFT HOISTING ROPES Four basic designs of ropes are now employed for hoisting duties: (1) Six-strand, round strand ropes with fibre cores. (2) Six-strand, triangular strand ropes with fibre cores. (3) Non-rotating, multi-strand ropes. 0) Locked coil ropes. Round Strand Ropes (Figure 1) Very solid and reliable ropes can be obtained with this simple geo-metric design of strand. 1'1?iangula1? Strand Ropes (Figure 2) Owing to the fact that the wires in the strands are bent over a triangle, they do not seat quite so solidly as when they are bent over a circular core wire, as is the case with

Jan 1, 1963

By Neil Campbell

Abstract Following discovery on the Giant property of very promising gold deposits, some of which terminate against the steeply-dipping West Bay fault, a geological study was initiated co locate possible faulted extensions of the ore. Geological mapping revealed that the ore and the shear zones to which the ore is confined are older than the fault and therefore subject co displacement by it. It also disclosed several diabase dykes which seem co provide the best basis for determining the fault movement. After applying various techniques co determine their strikes and dips, the dykes were used as structural markers and it was estimated that, subject co certain possible errors, the movement on the fault was 16,140 feet (3.06 miles) south and 1,570 feet (0.297 miles) down on the west side relative co the ease. Evidence supporting this conclusion was obtained when subsequent deep diamond-drill holes intended to test the hypothesis cut an ore-bearing major shear zone which, so far as can be determined, is nearly identical with its present correlative on the Giant property. Introduction The fault under consideration follows a northerly trend past the west side of the original settlement of Yellowknife, which is situated 600 miles north of Edmonton and 400 miles from the Northern Alberta Railway terminus at Waterways, Alberta. The mining properties chiefly concerned include the southern part of the Giant claims, on the east side of the fault, and the Con-Rycon-Demelt claims, on the west side, 3Y2 miles to the south. Geological data were also obtained from the eastern part of the A. Y.E. property, which lies south of the Giant claims, and from the Negus, Meg, Yellorex, and Kam properties, which are south and southeast of the Con-Rycon-Demelt claims. Recognition of the major faults in the Yellowknife Bay area, including the West Bay fault which appears to be the greatest, resulted from the work of Dr. A. W. Jolliffe (McGill University, formerly of the Geological Survey of Canada) in 1935 and subsequent years. It has been stated with little exaggeration that these faults rank with the largest known steeply-dipping dislocations of the earth's crust. In the winter of 1939, a mineralized shear zone named the Creek Vein was found on the Giant property. It was noticed that the space relationship between the new shear zone and a body of quartz-feldspar porphyry is roughly the same as that between the Con C-4 shear zone and a body of acidic flows lying north of the Con property. Coupling this relation with the assumption that the movement along the fault is dominantly horizontal, it was postulated that the Giant shear zone represented the faulted extension of the Con C-4 shear.

Jan 1, 1947

By E. H. Henderson

Introduction Stamp-Milling and amalgamation is, perhaps, one of the oldest processes of recovering gold from its ores. Many papers, theses, and textbooks have been written on the subject of stamp-milling practice in general, but, to my knowledge, there have been no publications describing the modern stamp-mill as designed, developed, and operated in Nova Scotia. Although it may be said that the gravity stamp-mill is the most primitive, and perhaps the crudest, crushing machine in existence, it is at the same time the most satisfactory all-round milling and amalgamating device yet contrived. Originating in Saxony, and used in North America first in Virginia and Georgia, the stamp-mill, in a primitive form, later found its way to California and Colorado. Here, it speedily developed from an affair of wood shod with iron, and operated with the crudest gearing, to substantially its present form. Briefly, it consists (see Figure 1) essentially of a series of hammers (the stamps), which fall upon a mixture of ore and water contained in a cast-iron box (the mortar). The resulting crushed ore (the pulp) is splashed out through a screen on the front of the box. For some years after the discovery of gold in Nova Scotia, in 1861, the ? arrastra and Chilean mill were used to recover the gold from the rich ores. The stamp-mill followed, and various types were used, principally the California and Gilpin County types. Then, in 1895, Mr. M. R. O'Shaughnessy, one of our foremost amalgamators, conceived the idea of a new type of stampmill, which has since become standard in Nova Scotia gold mines. This mill, unique in its design and operation, is specially adapted for the most efficient extraction and recovery of gold as it occurs in our Nova Scotian ores. It is commonly known as the Underwater Feed type, as opposed to the usual Overwater or Top Feed type, and it may be rightly termed The Nova Scotia Self-Classifying Stamp Amalgamation Mill. It is conceded by experienced mill-men that it is superior to any other type of mill for recovering the very coarse and granular gold typical of the ores of this Province. The particular installation and practice to be described in this paper is that of the Guysborough Mines, Limited, at Goldenville, Guysborough county. Emphasis will be laid on certain operating innovations of extreme simplicity and high efficiency.

Jan 1, 1935

By C. H. Stockwell

"The Precambrian rocks of southeastern Manitoba contain a great variety of mineral deposits, including gold, chromium, copper, nickel, lithium, tin, beryllium, tungsten, and molybdenum. Although considerable interest has been shown from time to time in each of these types of deposit, production to date has been almost entirely in gold. This has had a value of about $26,000,000 and has been derived chiefly from the San Antonio mine, with lesser amounts from the Central Manitoba, Gunnar, Beresford Lake, Ogama-Rockland, Diana, and other properties.Most of the deposits lie within volcanic and sedimentary rocks or within basic intrusions cutting these rocks. These favourable rocks occur in several areas, which have been given local names and are separated from one another by large bodies of granite (Fig. 1).In general, the several areas are characterized by different types of mineralization. Thus, the Rice Lake-Beresford Lake area contains numerous gold deposits and has yielded almost all the gold production to date; the Maskwa River, Euclid Lake, and Oiseau River areas are, on the whole, characterized by deposits of chromium, copper, nickel, lithium, tin, and beryllium; and in the West Hawk Lake area there are deposits of gold, tungsten, molybdenum, and lithium.As might be expected in a district containing such a variety of mineral deposits, the structural conditions controlling their deposition also vary greatly. It is, accordingly, convenient to discuss the structural geology and mineral deposits of each of the more important areas separately."

Jan 1, 1954

By R. E. Gilmore

PREAMBLE THIS PAPER comprises material presented in two separate 'Papers at the British Commonwealth Scientific Specialist Conference on Fuel Research held in London, England, in July, 1950. These papers are now available for publication in Canada, since only essential parts of the conference discussions, in addition to the resolutions resulting therefrom, will be published in the official Proceedings of the Conference. Inasmuch as the information presented concerns Canadian organizations and training facilities for fuel research, it should be of general interest to Canadian scientists, and especially to the Coal Division of the Canadian Institute of Mining and Metallurgy. Part I, the alternate title of which is Facilities in Canada for Fuel Research and for Exchange of Information and Staff, does not include research on peat, oil shale, petroleum oils in general, and natural gas, and omits studies of the geology, constitution, and production of coal. Special reference is, however, made to research on the heavy crude oils and bitumen of the Western Prairie Provinces, and particularly to their production and treatment to produce crudes for oil refinery processing.

Jan 1, 1951

By P. Langlois, G. Labonté, J. J. Barrett, J. Holmes

"The Voisey’s Bay mill processes a high-grade pentlandite and chalcopyrite ore in a largely pyrrhotite/troilite matrix. From 1994 to 1997, circuit development focused on making a 14% nickel concentrate. When flowsheet development resumed in 2001, the target grade was raised to 20% ni. initially triethylene tetramine and sulfite pyrrhotite depressants were used in a lime circuit, but by recycling process water and the contained thiosalts, the required nickel grade was made without depressants. construction of the mill was fast-tracked, with start-up in september 2005. ramp-up was faster than other recent nickel installations, with tonnage being limited by concentrate dewatering due to higher-thanexpected ore grades.RÉSUMÉ l’usine de traitement de Voisey’s Bay traite un minerai à teneur élevée en pentlandite et chalcopyrite dans une matrice formée surtout de pyrrhotite/troïlite. De 1994 à 1997, le développement du circuit ciblait la production d’un concentré à 14 % de nickel. lorsque le développement du schéma de traitement a été repris en 2001, la teneur cible a été élevée à 20 % de ni. initialement les déprimants triéthylènetétramine et sulfite de la pyrrhotite étaient utilisés dans un circuit à la chaux; cependant, en recyclant l’eau du procédé et les sulfosels qui y sont contenus, la teneur en nickel a été atteinte sans utilisation de déprimants. la construction de l’usine de traitement a été accélérée et elle a démarré en septembre 2005. la mise en opération a été plus rapide que pour d’autres installations récentes de nickel; le tonnage traité étant limité par le séchage du concentré en raison des teneurs de minerai plus élevées que prévu.INTRODUCTIONnickel was discovered on canada’s east coast in the vicinity of Voisey’s Bay, northern labrador, by chislett and Verbiski (Higgins, 2011) while working for Diamond Fields resources in 1993. The ovoid deposit was subsequently delineated in the winter of 1994–1995. By the end of 1995, the ovoid had been well explored, and at that time was thought to have a reserve of at least 30 million tonnes (Mt), with an average grade of 2.83% ni and 2.0% cu (naldrett, singh, Krstic, & li, 2000). Drilling to the east of the ovoid indicated the presence of significant mineralization. in June 1995, inco limited bought a 25% share in the Voisey’s Bay nickel company (VBnc), which was a subsidiary holding company set up by Diamond Fields. inco also bought 8% of Diamond Fields and negotiated the right to sell all the nickel produced from VBnc for 20 years as part of this agreement. in april 1996, inco bought Diamond Fields and acquired the remaining 75% of VBnc shares."

Jan 1, 2017

By William W. Shilts

"In carrying out a geotechnical survey of a proposed gas pipeline route from the Arctic Islands south to Longlac, Ontario, the Polar Gas Consortium contracted the drilling of several hundred 2- to 2D-m-deep boreholes in drift and bedrock. Samples from these holes were made available to the Geological Survey of Canada, where they were subjected to stratigraphic and trace-element geochemical analyses. The geochemical characteristics of the clay and sand-sized heavy mineral fractions of till samples from these boreholes have been summarized in a series of geochemical profiles.From the proposed pipeline terminus at Longlac northward to the vicinity of God's River in Manitoba, tills contain significant amounts of Paleozoic carbonate rocks and Proterozoic sedimentary rocks derived from the Hudson Bay basin and lowlands. Within this section, two sites were enriched in base metals, indicating the possibility of local mineralization of possible economic interest.From God's River northward to Seal River, Manitoba, no evidence of local mineralization was noted. The heavy mineral fractions of the tills are universally enriched in Mn-rich siderite thought to originate on or in the Paleozoic section of the Hudson Bay lowlands.From Seal River northward to Thelon River, near Baker Lake, tills contain only components originating west of the Hudson Bay sedimentary basin. Near the Keewatin-Manitoba border, all till is enriched in uranium, which probably originates in the ""young"" porphyritic granites underlying much of the region, and produces a distinctive airborne radiometric anomaly.At the Thelon River, multiple till sections are variously enriched in Cr, Ni, U, Cu and Mo in the vicinity of a distinctive aeromagnetic anomaly.From Thelon River northward, several coincident zones of chromium and uranium enrichment are found where the line of boreholes crosses east-west-striking belts of volcanic, ultramafic and sedimentary rocks of the Prince Albert Group.The results of this study indicate that till tends to have characteristic element associations or concentrations over each of several broad regions along the pipeline route. These are related both to large-scale bedrock associations and to largescale effects of glacial dispersal. In addition, the samples, collected more or less at random with respect to local bedrock geology, have intersected several small-scale geochemical anomalies that appear to be related to zones of mineralization of possible economic interest."

Jan 1, 1980

By C. R. Julian

THE large pyrites ore-bodies, the underground mining of which is to be described, are situated at Rio Tinto in the Province of Huelva in Southern Spain. The situation of the different ore-bodies with relation to one another is shown in Figure 1. It will be seen on the plan that the strike of the ore-bodies is approximately east and west. The geology of the district has been very fully described by Dr. D. Williams (1), so that for the purposes of this paper it will be sufficient to give briefly the salient features o each of the two larger ore-bodies which are being mined by underground methods at the present time. (a) San Dionisio.-This ore-body is the largest single deposit in Rio Tinto, having on its upper levels a length of 3,500 ft. On the upper levels the average width is approximately 200ft. but in places on the lower levels there is a width of 900ft. of un broken pyrites. Diamond-drill holes, without running out of ore, show the ore-body to persist to a depth of at least 1,600 ft. The ore-body in the upper part lies between slate and porphyry walls, but in depth is enclosed in porphyry walls. (b) South Lode.-Faulting is considered to be responsible for the break in the solid ore between South Lode and San Dionisio. On the upper levels, the South Lode ore-body has an unbroken length of 4,000 ft. The massive pyrites has a maximum width of 300ft. and an average of about 100 ft. Ore has been proved to a depth of 1,000 ft., at which depth the ore-body is much reduced both in length and breadth. This ore-body, to the depth at which it has been proved, lies entirely between slate and porphyry walls. The South Lode and the San Dionisio ore-bodies are mined both by open-cast and by underground methods. There is evidence that these mines have been exploited intermittently during the last 3,000 years; but, as is to be expected, no records are available of the tonnage mined prior to the time of purchase by the present company.

Jan 1, 1940

By R. M. Graves, C. B. McKenzie, D. Barbour, D. W. Desnoyers

"Abstract -The prospective Tulks volcanic belt hosts five significant massive sulfide deposits, Tulks Prospect, Tulks East, Jack's Pond, Daniel's Pond and Victoria Mine, as well as numerous showings and indications throughout its 70 km outcrop length. Regionally, the 498 Ma sequence consists dominantly of felsic pyroclastic rocks and flows with interbedded mafic volcanic units and fine­ grained sediments, commonly graphitic. Contemporaneous granitoid rocks occur in the south half of the belt. Rocks usually display a strong NE-SW, steeply dipping, penetrative foliation and other shear-related high-strain fabrics. Facing directions are normally northwest, although there is local evidence of folding. Sulfide bodies and their alteration systems are deformed and shape-modified in the style of ambient strain.The Tulks, Tulks East and Jack's Pond prospects appear to occupy a similar stratigraphic level, on or near the contact between a thick felsic pile and an overlying broad, conductive package of graphitic sedimentary rocks. AU are pyritic deposits with well-developed footwall alteration systems. The Tulks prospect comprises four polymetallic lenses totalling 750 000 t. Three lenses constituting more than 6 000 000 t of sulfide mineralization are indicated at Tulks East but only the 210 000 t ""B"" lens contains significant base metals. Jack's Pond consists of a very extensive, zoned alteration complex in which four lenses of massive to semi-rnassive pyrite + chalcopyrite are known.The central part of the system, characterized by Mg chlorite and carbonate, is enveloped by pervasive sericitization and capped by intensely silicified and pyritized volcanics. The sulfide lenses are interpreted as part of the footwall zone and are beneath that part of the system most likely to host polymetallic massive sulfides.Daniel's Pond differs from the other prospects in such fundamental ways as metal content, associated alteration and structural setting. The deposit comprises strongly tectonized, Ag-rich, Zn-Pb mineralization distinguished by a pronounced Ba-As-Sb signature. Mineralization is confined to a narrow, north-south high-strain zone which separates unstrained mafic volcanic rocks to the east from well-foliated felsic rocks. The deposit Jacks an extensive alteration halo and at its north end is associated with a lens of barren, undeformed massive pyrite.The Victoria Mine deposit, the most cupriferous of the five, is related to a moderately dipping structure that separates well-foliated Tulks volcanic rocks from an overlying, Jess deformed volcanic­ sedimentary sequence that may be as young as 462 Ma. The structure is also the locus of black chlorite, dolomite and quartz alteration. Structurally remobilized precursor sulfide mineralization is one possible source for the deposit."

Jan 1, 1993

By Grant D. Nicholas

This paper compares an integrated evaluation approach to decision-making with more traditional sensitivity analysis and Monte Carlo simulation. The primary objective is to highlight the differences in NPV that can arise from using these evaluation methods in a top down and bottom-up approach. Results from three resource scenarios, derived from sampling a "virtual" ore body (reality) on grid spacings of 75m, 50m and 25m, are analyzed and compared.

May 1, 2007

By C. E. White

History The Con-Rycon mine is situated in the Yellowknife mining district, North West Territories, 608 air miles north of Edmonton, Alberta. The earliest reported discovery of gold in the area was made in 1898 but no extensive exploration occurred until 1928. The birth of Yellowknife as a mining community took place in 1934 with the staking of the Rich group and subsequent shipping of 16 tons of high grade ore. The Giant group was also among the claims staked in 1934, and later staking showed a tendency to close the gap between these two properties. In the fall of 1935, the A.Y.E. claims, situated south of the Giant group, were staked to cover a discovery of the Geological Survey of Canada and, after general release of the Survey's information, the adjoining ground was staked. These claims included the Con, Negus, Meg, and Kam groups. In 1936 four lapsed claims were re-staked as the P and G group and later acquired by Rycon Mines, Limited, controlled by the Consolidated Mining and Smelting Company of Canada, Limited. The Con and various adjacent groups owned by Cominco are now operated with the Rycon under one management. Surface trenching on the Con property started in 1936 and, during the fall and winter of 1936-37, a 60- foot 5 ft. by 9 ft. inclined prospect shaft was sunk. The encouragement provided by the shaft and diamond drilling in 1937 led to the decision to establish a mining plant, and in August, 1938, the 100-ton cyanide mill produced its first brick- the first gold brick poured in the history of the North West Territories. In November, 1938, the mill was enlarged to a 175-ton capacity and operated at this rate until 1941, when refractory ore was encountered. This situation was met by the installation of flotation and roasting units and, at the same time, the milling capacity was increased to 300 tons daily. Labour shortages and Government restrictions forced a reduction of output and in 1943 milling was suspended while mine development continued on a reduced scale throughout the war years. The present full-scale of operations was resumed in 1946 and the total production to the end of 1948 amounted to 288,853 oz. gold and 72,347 oz. silver.

Jan 1, 1949

By James J. Holmes

ACCIDENT prevention as we know and understand it today is of comparatively recent origin. As a matter of fact, the Industrial Accident Prevention Association of Ontario, which is the oldest organization of its kind in the Dominion, celebrated its thirtieth anniversary only this year. On the other hand, one could say that the history of accident prevention is almost the history of mankind itself. In a general sense, every forward step that man has made throughout the centuries has been largely due to two things: (1) a desire for increased comfort, and (2) the need for safety; and, always, the need for safety has taken precedence over the desire for comfort. While it is true that hundreds of volumes have been published, dealing with the many aspects of accident prevention work, you cannot go to a library and pick out a book that has all the answers in it. Such a book has never been published-we are still looking for some of the answers. However, a good deal of real progress has been made.

Jan 1, 1945

By J. E. Danoczi

ABSTRACT A diamond processing plant is being designed for the Star–Orion South diamond project in central Saskatchewan. Key to the plant is diamond liberation, which occurs in the comminution section and is the process of breaking up kimberlite rock as gently as possible to minimize diamond damage, particularly in larger, high-value diamonds. Kimberlite from the crater area of a volcanic pipe is generally softer than kimberlite from the diatreme zone. Softer kimberlite, comprising the majority of Star– Orion South deposits, can be readily broken up using abrasion and attrition by autogenous grinding mills, the preferred comminution method for minimizing diamond damage.

Jan 1, 2013