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By Oscar F. Tangel

This paper outlines Canada's current status in world iron ore markets, and evaluates t he prospects for the future. Estimates for the production, export and consumption of iron ore are given. Canada's major market will continue to be the United States, with the European Common Market countries, Japan and the United Kingdom also forming important outlets. The advantages held by Canada's major competitors in these latter three market areas are briefly discussed

Feb 1, 1966

By Fred G. Hewett

The Cassiar orebody is located in a sill-like serpentinite body intrusive into the Devonian-Mississippian sedimentary rocks of northern British Columbia. Subsequent intrusion of the Cassiar batholith formed the McDame synclinorium and produced chrysotile asbestos. Present information indicates an orebody of approximately 16,277,000 tons amenable to open-pit mining, but continued diamond drilling will be needed to accurately define total tonnage and grade. A program has been developed at the mine to provide the required information on a daily basis, and work is continuing on more effective dollar-value prediction methods.

Jan 1, 1978

By A. M. Cann, C. I. Godwin

"The Kemess porphyry copper-molybdenum deposit occurs in the Intermontane Belt of north-central British Columbia. The deposit is in andesitic to basaltic flows and tuffs which may be correlated with the Savage Mountain Formation of the Upper Triassic Takla Group. Most known chalcopyrite and molybdenite is associated closely with a 500-m-diameter zone of intense quartz-sericite-pyrite alteration. A zone of supergene enrichment, up to 30 m thick, underlies a leached capping about 20 m thick. The age of mineralization and the surrounding granodiorite and quartz monzonite pluton is Early Jurassic. K-Ar and Rb-Sr analyses indicate that the mineralization and alteration is slightly younger (l82±6 Ma) than the granitic intrusion (KAr: about 205±6 Ma; Rb-Sr: 190±4 Ma). The low 87Sr/J6Sr initial ratio for the granodiorite is typical of plutons in the Intermontane Belt.IntroductionKemess is a medium to small porphyry copper-molybdenum deposit with significant gold and silver values (Pilcher and McDougall, 1976). This paper describes the lithologies and alteration at this property; geochronology by Rb-Sr and K-Ar methods defines the ages of mineralization and surrounding plutons to be Early Jurassic.The property, located in the Thutade Lake area of northcentral British Columbia (NTS Map 94E; lat. 57°04'N; long. 126°44'W), is about 425 km northwest of Prince George (Fig. 1). Closest road access is 35 km southeast of Kemess. Final access must be by float plane or helicopter. The British Columbia Railway right of way passes 70 km to the southwest of theproperty.A prominent gossan zone at Kemess was staked in 1967 by Kennco Explorations (Western) Ltd. following detection of geochemical anomalies during stream sampling the previous year. During 1968, 1969and 1971, Kennco completed 232 m of X-ray diamond drilling, conducted geological mapping and carried out geochemical sampling of silts and soils (Stevenson, 1969; B.C. Ministry of Energy, Mines and Petroleum Resources, G.E .M., 1969 and 1971). Getty Mines Ltd. optioned Kemess in 1975and 1976. They remapped the area and diamond drilled 12 BQ and NQ holes, totalling 2065 m (B.C. Ministry of Energy, Mines and Petroleum Resources, Expl. B.C., 1975)."

Jan 1, 1980

By R. E. de Barrio, M. E. Lanfranchini, R. O. Etcheverry

"The El Abuelo Ca-Fe-magnetite skarn and related hydrothermal quartz veins are located at Cerro Pepita Hill, in southwestern Chubut province of southern Argentina, 1700 km southwest of Buenos Aires. These deposits are developed in a continental magmatic arc environment linked to the Andean orogeny. Iron skarn mineralization is mainly hosted by an Upper Jurassic to Early Cretaceous sedimentary sequence interbedded with Upper Jurassic basaltic andesite, and is spatially associated with Early Cretaceous calc-alkaline dikes. Ore grades vary between 40 and 63 wt.% Fe. In addition, anomalous metal contents (>10 000 ppm Cu and up to 81 g/t Ag) are present in the hydrothermal quartz veins.At least three paragenetic mineral assemblages have been identified in the El Abuelo exoskarn: (1) amphibole > epidote ± chlorite ± quartz, formed by isochemical contact metamorphism; (2) Fe-clinopyroxene ± Ca-garnet, formed during prograde metasomatic anhydrous exoskarn formation; and (3) actinolite ± epidote ± chlorite ± quartz ± magnetite > titanite, resulting from hydrous retrograde alteration of exoskarn. Endoskarn alteration involved an early Mg-Fe-clinopyroxene ± Fe-garnet assemblage followed by retrograde actinolite replacement of pyroxene. Lower temperature hydrothermal alteration related to quartz veins was superimposed on the skarn assemblages, showing an innermost sericite ± adularia ± pyrite ± chalcopyrite assemblage and an external propylitic halo.Some metallogenic characteristics of the mineralization and the geological setting resemble those in several iron oxide copper-gold deposits elsewhere in the world."

Jan 1, 2007

By I. C. L. Webster, G. E. Ray

"The magnetite-rich Heff Cu-Au skarn lies in the Quesnel Terrane of south-central British Columbia, approximately 26 km northeast of Kamloops. The skarn formed close to the northern margin of the Heffley Creek pluton, and is hosted by Carnian (Late Triassic) Nicola Group limestone. The Late Triassic pluton (208.1 ± 6.1 Ma, U-Pb zircon) is a composite body of alkaline affinity that includes dioritic, gabbroic, and magnetite-rich clinopyroxene ± olivine ultramafic phases.The skarn has been discontinuously traced along strike for more than 1 km, and individual skarn layers are up to 40 m thick. The most common non-opaque minerals are garnet, clinopyroxene, and carbonate, with lesser epidote, biotite, amphibole, and chlorite. Apatite locally forms more than 3 vol.% of the rock. Compositionally the garnet is a low Mn grandite averaging Pyr3-Grs41-Adr56 mol.%.Mineralization consists of lenses, up to 10 m thick, containing massive low Ti-V magnetite (avg. 0.03 wt.% TiO2 and 0.01 wt.% V2O3). Magnetite is associated with up to 20 vol.% pyrrhotite, lesser pyrite, and trace chalcopyrite and gold. There is a moderate enrichment in rare earth elements with assays up to 570 ppm La and 490 ppm Ce. The Heffley Creek pluton belongs to a suite of Late Triassic-Early Jurassic alkalic and Fe-rich intrusions that are widely developed throughout the Quesnel Terrane. Some host Cu-Au porphyry mineralization, but less commonly they are associated with magnetite-apatite veins such as at the Glen Iron mine and Magnet occurrence, or with magnetite-rich Cu-Au skarns such as the Heff occurrence.Although abundant low Ti magnetite is present in the Heff skarn, it does not appear to represent iron oxide copper- gold (IOCG) type mineralization. Microprobe analyses completed during this study show that low Ti magnetite is not a unique feature of IOCG deposits, but also characterizes some other types of hydrothermal mineralization. In British Columbia these include some alkalic porphyry-related magnetite-apatite veins in the Quesnel Terrane, as well as the well-known Wrangellia-hosted Fe skarn deposits. Thus, low Ti magnetite appears to be a common signature of many magmatic hydrothermal deposits in contrast to the high Ti primary magnetite found in most igneous rocks."

Jan 1, 2007

By R. H. Sheaphim

THE RECENT and continuing activity in the Boundary district, British Columbia, makes the publication of this paper timely. The following description and discussions are based on two years' experience in the district as Field Manager and Geologist for Attwood Copper Mines, Limited. The Attwood project was organized by Dr. D. F. Kidd to re-examine the Boundary mining camp. Thanks are due to Dr. Kidd, both for his intelligent guidance during the project and for his permission to publish this paper. Much of the data and many of the interpretations presented are credited to the work of, and to discussion with, Dr. W. H. White, Consultant Geologist, who worked for two field seasons on the project. However, the author assumes the responsibility for this presentation. Dr. C. D. A. Dahlstrom worked with the author during the latter stages of the project. His assistance and advice are gratefully acknowledged.

Jan 1, 1956

By J. F. Wright

The cold, or Kississing, Lake area in northwestern Manitoba was the scene of considerable prospecting and mining activity last summer. At the Sherritt-Gordon property, four diamond drills were at work exploring a large deposit of copper and zinc ore, and underground work was in progress on this deposit from two shafts. Some preliminary diamond drilling was completed in five other deposits, and surface exploration work was in progress at a dozen or more additional localities where copper and zinc sulphides were known to be present. Many prospectors visited the area and spent some time in search for new deposits, but apparently few discoveries were made; consequently, last autumn some returned a little disappointed in the area as a prospecting field. Although many visited Cold Lake area last summer in the search for mineral deposits, it should be emphasized that this new prospecting field is a very large one, and that to date only a small proportion of the ground has been examined, except in a very general way. Within the past 18 months, a village of several dozen cabins, and with a population of l00 or more persons, has sprung up on the shore of Cold lake, just west of the Sherritt-Gordon mine. This at present is the business centre of the area, and two banks, a post office - named Kississing by the Postal authorities - a Mining Recorder's office, as well as several restaurants and stores carrying a fairly complete stock of groceries, dry-goods, and general prospecting equipment, are already established.

Jan 1, 1929

By W. T. Irvine

Introduction The property of the Britannia Mining and Smelting Company is on the east side of Howe sound, some twenty miles north of-Vancouver. The camp is served by two settlements, one at Britannia Mines townsite, approximately three miles from the water's edge at an altitude of 2,100 feet, the other at Britannia Beach, on Howe sound. The first discovery of copper ore on the property was made in 1888, but it was not until 1905 that production started. From that year until the end of 1944, production had totalled 732,414,420 pounds of copper and 261,126 ounces of gold from six orebodies, known as the Victoria, Empress, No. 5, Fairview, Bluff, and Jane. No. 8 orebody, with which this paper is concerned, was discovered in 1937 by diamond drilling from the 4100 level, some 300 feet above sea level. Development of this orebody to the end of 1944 had included the sinking of a shaft from the 4000 to the 5250 level, and a limited amount of stoping. This work has delimited the orebody from the 3800 to the 4950 level and has indicated upwards of 1,000,000 tons of copper-zinc-gold ore. It is planned to commence production in the near future, while continuing exploration of the orebody at depth.

Jan 1, 1946

By G. J. Simandl

"Since the 1980s, China has become the predominant producer of REEs. Recently, it introduced REE export quotas and this started a world-scale REE exploration rush. REE resources are concentrated in carbonatite-related deposits, peralkaline igneous rocks, pegmatites, REE ± P veins, ion adsorption clays, placers, and some deep ocean sediments. REEs could also be derived as a by-product of phosphate fertilizer, U processing, Ti-Zr-bearing placers, and exploitation of Olympic Dam-type sub-type of IOCG deposits. The ideal REE development target would be located in a politically stable jurisdiction such as Canada. REE grade and tonnage, mineralogy, and permissive metallurgy are some of the key technical factors that could be used to screen projects. INTRODUCTIONAccording to the International Union of Pure and Applied Chemistry (IUPAC), the term “rare earth elements” (REEs) encompasses yttrium (Y), scandium (Sc), and the lanthanide series: lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu). This definition is used throughout this paper.REEs are subdivided into light (LREE) and heavy (HREE) categories. LREEs include, Sc, La, Ce, Pr, Nd, Sm, Eu, and Gd and HREE include Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y. Promethium (Pm) does not occur in nature. Concentrations of individual LREEs in the upper crust of the Earth are comparable to those of base metals. Even the least abundant REE (Lu) is about 200 times more abundant than gold.The production of REEs, reported in the form of oxides (REOs), for 2011 is estimated at 140 000 t (Figure 1a). Although high technology industries can substitute several REEs with other materials, these substitutes are typically more expensive or less effective than the REEs they replace. A number of countries, including the United States, consider several REEs essential for national security, their economy, and a general reduction in green house gas emissions. The forecasted demand for individual LREOs is much higher than that of HREOs (Figure 2). Dy, Eu, Tb, Nd, and Y are essential for the US economy and subject to predicted supply disruptions (U.S. Department of Energy, 2010)."

Jan 1, 2012

By A. C. A. Howe, J. C. Rowntree

"The Bernie Lake pegmatite near Lac Du Bonnet in southern Manitoba is a complexly zoned pegmatite containing several lithium-bearing units in addition to the western world's largest known reserve of cesium. The pegmatite forms a flat-lying ellipsoidal body within an east-west-trending Precambrian amphibolite. The pegmatite enclosed by this vertically schistose amphibolite lies near the eastern tip of a granitic intrusive. The relationship of this intrusive to the pegmatite is obscured by Bernie lake. To date, the pegmatite body has been delineated aver an area of approximately 80 acres; it attains a maximum thickness of 280 feet. Several distinct zones, including three assemblages of economic importance, comprise the pegmatite itself. The combined spodumene and lepidolite assemblages provide a recoverable defined lithium ore reserve of almost 5 million tons averaging more than 2 per cent lithium oxide. The recoverable cesium ore of the pollucite assemblage provides 300,000 tons averaging more than 20 per cent cesium oxide; this represents more than half of the western world's pollucite reserve. The Bernie Lake pegmatite deposit, owned by Chemalloy Minerals Limited, is well located with respect to the growing United States markets, and its reserves of cesium are large enough to enable it, under favourable economic circumstances, to become the major producer of this metal in North America."

Jan 1, 1967

By W. O. Karvinen

"In the Timmins area, a close spatial and chronological association exists between gold deposits and two major stratabound carbonate-rich members and related quartz-feldspar porphyries. Synvo/canic and metamorphogenic are the two main types of mineralization recognized. Synvolcanic ores include the stratiform quartz-ankerite ""veins"", pyritic carbonates and chert-carbonate-tuff sedimentary rocks and epigenetic ventrelated breccias and stringer zones. Metamorphogenic ores consist of quartz-carbonate fracture fillings in dilatant zones developed during various phases of regional deformation and metamorphism. They are classically epigenetic in character.The evidence suggests a primary syngenetic enrichment of gold on the ocean floor and in vent areas during submarine felsic volcanism and related exhalative-hydrothermal activity followed by further enrichment into quartz-carbonate stockworks during regional deformation and greenschist metamorphism.Although normally thin (a few hundred metres), carbonate members in Archean volcanic terrain represent intense hydrothermal activity which could have transported and enriched gold. They should be used to locate fossil vents and structurally favourable zones where economic concentrations of gold may be found."

Jan 1, 1982

By J. G. Pearson, F. H. MacDougall, A. G. Galley

The difference in age, host rock lithology, alteration and style of mineralization indicates a fundamental difference in the format ion of gold deposits in the Flin Flon and Amisk Lake areas. The Flin Flon area contains early quartz-sulfide-gold veins fo rmed within intermittently active fractures and later plutonic hosted deposits thought to be generated in a porphyry system. In the Amisk Lake area two types of gold occurrences are recognized: I) gold-quartzcarbonate- sulfide veins within or flanking fault zones and 2) structurally and stratigraphical ly controlled zones of dissem inated and vein type sulfide-gold mineralization within extrusive and intrusive rhyolite and dacite porphyries. Both types of deposits are set within supracrustal rocks. are accompanied by intense alteration haloes and were formed prior to the major deformation event suggesting an early, epigenetic hydrothermal origin.

Jan 1, 1986

By Mark W. Masson, David B. Stevenson, David W. Broughton, Douglas R. Cruji, Steven E. Parry

"Abstract-The Amalgamated Kirkland gold deposit is located at Kirkland Lake, Ontario, within the Archean Abitibi Greenstone belt of the Canadian Shield. It lies on a fault or "break", termed the Cyprus Break, which is a splay off a regional structure termed the Cyprus-Battle Mountain Break. The Cyprus Break merges with the Cyprus - Battle Mountain Break above the -250 m level, as it was not encountered in shallow drilling or surface exploration. These structures lie 1.5 km south of the 727 000 kg (23 million ounce) Kirkland Lake Main Break and 0.5 km north of the 872 000 kg (30 million ounce) Larder Lake Break.The deposit is hosted by alkalic Timiskaming Group volcanic and sedimentary rocks which are overthrust by older Larder Lake Group tholeiitic and komatiitic flows along the Larder Lake Break. Timiskaming syenitic intrusives, similar to the host rocks for the Kirkland Lake Main Break gold deposit, intrude both suites.The Amalgamated Kirkland deposit consists of lode-style gold mineralization which is mainly hosted by altered and pyritized Timiskaming trachytic volcanics which wedge out or thin at depth, between two sedimentary units. The intersection of the Cyprus - Battle Mountain and Cyprus Breaks, in conjunction with the westward plunge of the volcanic wedge, appears to control the westerly plunge of the Amalgamated Kirkland deposit at approximately 50º.Mineralization is characterized by blue-gray brecciated and "wormy" quartz-ankerite veins which contain up to 10% fine-grained pyrite and, in decreasing order of abundance, minor galena, chalcopyrite, sphalerite, molybdenite and visible gold. The sulfides and gold commonly occur along fractures and wallrock inclusions within the veins. Native gold occurs as fine pinpoints distributed in 1-mm to 5-mm size clusters of up to ten or more grains.The auriferous veins occur within a quartz-ankerite-sericite-pyrite alteration assemblage which is enveloped by a broader zone of ankerite-sericite±hematite±quartz-pyrite alteration up to 60 m wide. This latter assemblage overprints the regional greenschist-facies chlorite-calcite assemblage.The Amalgamated Kirkland property has had a long history of exploration activity beginning with the first discovery of mineralization in 1911 on the Hunton Shaft claim located in the northeast corner of the property. Since that time various prospecting, mapping, trenching, geophysical surveys and diamond drilling programs have concentrated on either carbonate zones along the Larder Lake Break or quartz veins along the northern side of the property in association with complex trachyte flows and syenite dikes.Battle Mountain Canada Inc. located the Cyprus - Battle Mountain Break through a prospecting, trenching and geophysical program in 1989. Drilling by Battle Mountain and Cyprus Canada under the surface showing, coupled with several revisions to the structural interpretation of the Cyprus - Battle Mountain and Cyprus Breaks, resulted in delineation of the Amalgamated Kirkland deposit. Location of an auriferous structure through basic surface exploration within 1 km of a world-class orebody demonstrates both the subtle nature of Archean gold deposits and the potential for finding new mineralization in heavily prospected camps."

Jan 1, 1995

By Mark W. Masson, David B. Stevenson, David W. Broughton, Douglas R. Cruji, Steven E. Parry

"The Amalgamated Kirkland gold deposit is located at Kirkland Lake, Ontario, within the Archean Abitibi Greenstone belt of the Canadian Shield. It lies on a fault or “break”, termed the Cyprus Break, which is a splay off a regional structure termed the Cyprus-Battle Mountain Break. The Cyprus Break merges with the Cyprus – Battle Mountain Break above the -250 m level, as it was not encountered in shallow drilling or surface exploration. These structures lie 1.5 km south of the 727 000 kg (23 million ounce) Kirkland Lake Main Break and 0.5 km north of the 872 000 kg(30 million ounce) Larder Lake Break.The deposit is hosted by alkalic Timiskaming Group volcanic and sedimentary rocks which are overthrust by older Larder Lake Group tholeiitic and komatiitic fows along the Larder Lake Break. Timiskaming syenitic intrusives, similar to the host rocks for the Kirkland Lake Main Break gold deposit, intrude both suites.The Amalgamated Kirkland deposit consists of lode-style gold mineralization which is mainly hosted by altered and pyritized Timiskaming trachytic volcanics which wedge out or thin at depth, between two sedimentary units. The intersection of the Cyprus – Battle Mountain and Cyprus Breaks, in conjunction with the westward plunge of the volcanic wedge, appears to control the westerly plunge of the Amalgamated Kirkland deposit at approximately 50º.Mineralization is characterized by blue-gray brecciated and “wormy” quartz-ankerite veinswhich contain up to 10% fne-grained pyrite and, in decreasing order of abundance, minor galena,chalcopyrite, sphalerite, molybdenite and visible gold. The sulfdes and gold commonly occur alongfractures and wallrock inclusions within the veins. Native gold occurs as fne pinpoints distributed in 1-mm to 5-mm size clusters of up to ten or more grains.The auriferous veins occur within a quartz-ankerite-sericite-pyrite alteration assemblage which is enveloped by a broader zone of ankerite-sericite±hematite±quartz-pyrite alteration up to 60 m wide. This latter assemblage overprints the regional greenschist-facies chlorite-calcite assemblage.The Amalgamated Kirkland property has had a long history of exploration activity beginning with the first discovery of mineralization in 1911 on the Hunton Shaft claim located in the northeast corner of the property. Since that time various prospecting, mapping, trenching, geophysical surveys and diamond drilling programs have concentrated on either carbonate zones along the Larder Lake Break or quartz veins along the northern side of the property in association with complex trachyte flows and syenite dikes.Battle Mountain Canada Inc. located the Cyprus – Battle Mountain Break through a prospecting, trenching and geophysical program in 1989. Drilling by Battle Mountain and Cyprus Canada under the surface showing, coupled with several revisions to the structural interpretation of the Cyprus –Battle Mountain and Cyprus Breaks, resulted in delineation of the Amalgamated Kirkland deposit. Location of an auriferous structure through basic surface exploration within 1 km of a world-class orebody demonstrates both the subtle nature of Archean gold deposits and the potential for finding new mineralization in heavily prospected camps."

Jan 1, 1995

By W. L. Murphy

The Star Lake property, located 115 km northeast of La Ronge, Saskatchewan is underlain by metamorphosed andesitic tuffs and flows which have been intruded by the dioritic to granitic Star Lake Pluton. Gold mineralization on the Star Lake property was first discovered at Ru h Lake by E. Beveridge in 1959 and by M. and E. Hird in 1961. In 1960 E. Partridge discovered Kahn 18 and Kahn 28. In 1982 the SMDC-Starrex joint venture completed geophysical and geochemical urveys including magnetics, VLF, IP/Resistivity, vegetation, bulk till and oil sampling, followed by drill testing of pecific targets. To date the most ignificant depo it is the 21 Zone which contain drill indicated reserves of 230,000 tons grading 0.5 oz/ton Au . The 21 Zone con ists of quartz with 5-10% (locally > 30%) drusy pyrite, minor chalcopyrite and trace amounts of scheelite, chalcocite and arsenopyrite. The 21 Zone is enclosed by a 25-50 m wide band of mylonitized monzonite. The mylonite occurs in the central portion of a 300 m wide northeasterly trending zone of brittle deformation .

Jan 1, 1986

By H. Fuchs, W. Hilger, E. Prosser

"The Lone Gull discovery of Urangesellschaft Canada Limited was made in 1974 as a result of extensive exploration activities for unconformity related uranium deposits in the Baker Lake area of the Northwest Territories. The structurally controlled mineralization is hosted in Aphebian metasediments and intrusive granitic stocks located approximately 2 km south of the unconformity between the Lower Proterozoic Aphebian and the Middle Proterozoic The/on Formation.The original discovery was made with a helicopter mounted radiometric system during systematic prospection over the unconformity. Diamond drilling was first carried out in 1977 and continued, with an interruption in 1981, to the present. A total of 25,500 metres and 199 holes have been drilled and outlined three ore zones. Preliminary geological reserves are estimated at some 16 million kgs. U30 8 at an average grade of approximately 0.4%.IntroductionUrangesellschaft initially entered exploration in Canada as a participant in joint ventures in 1968, and was incorporated in Canada in 1974 as Urangesellschaft Canada Limited. Subsequently, UG was among the first companies to apply exploration criteria developed from the Athabasca Basin, namely the Middle Proterozoic unconformity over Archean/ Aphebian basement, for selection of exploration targets in the geologically similar Thelon Basin.The Baker Lake area in the Keewatin District of the Northwest Territories was selected from the extensive Thelon Basin because it had the best accessibility (Fig. 1). The hamlet of Baker Lake located close to the geographical centre of Canada, is largely an Inuit settlement with a population of approximately 1,100 inhabitants. The distance from Baker Lake to the Lone Gull property is about 80 km. Baker Lake is connected to the tidewater of Hudson's Bay via Chesterfield inlet and is serviced by scheduled domestic flights several times weekly from Churchill, Manitoba, about 650 km to the south."

Jan 1, 1986

By Dennis E. Bell

"This paper describes exploration and development to 1982 in the southern half of the northeastern British Columbia (Peace River or Northeast Block) inner foothills metallurgical coal belt. Gates Formation, Fort St. John Group, is the primary target; Gething Formation, Bullhead Group, is secondary. This part of the belt remains wilderness when compared to its other parts. Practical formational and structural mapping is described. A local problem known as the Secus Mountain or Mount Belcourt conglomerates is discussed. The three major explorers have been Denison Mines, PetroCanada, and Crows Nest Resources, all with partners. Initial mine construction and rail spur construction are continuing. The new town of Tumbler Ridge is being built. Introduction This paper describes exploration and development to 1982 in the southern half of the northeast British Columbia metallurgical coal belt. The area (Fig. 1) trends 120 km northwest from the Alberta border to the Wolverine River and Bullmoose Creek. The belt averages 15 km in width, and is 20 km at its widest. Physiographically, the area is dominated by rugged inner foothills, with relief to 1,500 m. The trend of the structures is transected by a dozen rivers flowing southwest to northeast away from the Continental Divide. The Rockies, lying immediately to the west, control the climate. One fact continues to colour all coal work in the area. When compared to the other parts of the western Canadian foothills and Rockies coking belt, it remains the least accessible and least mapped portion. Lack of access also makes all work expensive. Current activity centres about two mines in construction at the northwestern end of the area. Denison Mines and partners are developing their Quintette project, and Teck Corporation and partners are developing their Bullmoose project. PetroCanada and partners have intensively explored their Monkman-Duke Mounta,in project, but mine construction awaits better economic times. The rest of the area remains lightly explored, with the exception of some intensive work on particular structures by Denison and Petro-Canada. The focus of coal work has been metallurgical bituminous coal seams contained primarily in the Gates Formation (Fig. 2) and secondarily in the Gething Formation. These formations are found in generally en-echelon structures ranging to several kilometres in width."

Jan 1, 1985

By A. A. Burgoyne

"The McDame chrysotile asbestos deposit located near Cassiar in northern British Columbia isfound at depth and on trend to the southeast of the currently mined open-pit Cassiar asbestos deposit. The ultramafic rock hosting the McDame is serpentinized peridotite of the Upper Paleozoic Sylvester Group contained in an ophiolitic sequence preserved within a lower thrust sheet of the Sylvester Allochthon. The Sylvester stratigraphic package is a series of thrust slices composed of argillite, tuff and volcanic flows, diorite and serpentinite. Contacts between units are often fault-controlled.The McDame asbestos-bearing ultramafite is considered to represent a separate interleaved fault-bounded slice of rock distinct from the Cassiar asbestos deposit.Asbestos mineralization of the McDame deposit was discovered in /978. Exploration during /980 and /98/ focused on extensive underground drilling of the deposit and in /983 on geological mapping, airborne and ground magnetic surveys. In /984 a 622.5 m borehole was drilled with a 242 m intersection of McDame ultramafite of which the lower 15/ metres contain potentially economic chrysotile asbestos. The McDame deposit averages 90 m thick, trends north-south, dips easterly and plunges southeasterly. The deposit is estimated to contain geological reserves in the order of 62 million tonnes containing asbestos fibre similar in value to the Cassiar deposit.The McDame is considered a major world-class asbestos deposit. A decision to develop and mine the deposit will require further substantial underground exploration and evaluation. A + 1200 m exploration adit driven to the hanging wall of the deposit was undertaken in 1985 in anticipation of bulk sampling and diamond drilling in 1986."

Jan 1, 1986

By L. E. Young

"The Red Dog deposit of the western Brooks Range, Alaska was discovered in the 1970s. Two mineralized areas are present, the Main and Hilltop deposits. With indicated and inferred reserves of 77 million tonnes of 17.1% zinc, 5.0% lead and 82 g/ tonne silver, the Main deposit of Red Dog represents one of the world's largest zinc-lead deposit s. Since serious evaluation by Cominco commenced in 1980, a better understanding of deposit geology has been gained through 10 715m of diamond drilling and concurrent geologic, geophysical and geotechnical studies. The Red Dog deposit is of Mississippian to Pennsylvanian or Early Permian age, and straddles a redox transition in fine-grained and chemical sediments of the Red Dog structural sequence.The Main deposit has been modified by regional Mesozoic thrust faulting and isoclinal folding, resulting in complex interrelationships between silica rock, sulphide rock and barite. Multiple lines of evidence suggest the Main deposit contains both a syngenetic stratiform and a replacement component. Ore fluids were probably derived by regional lateral movement of brines through a coarse clastic footwall aquifer, then upwards along block faults to the site of the Red Dog deposit.Historical PerspectiveThe region in the vicinity of the Red Dog deposit (Fig. 1) was first prospected by J. W. Kelley in the late 1880s (Orth, 1967). The first coordinated inland exploration was conducted by the U.S. Geological Survey in 1910-1911 and 1923-1926 (Smith, 1913; Smith and Mertie, 1930). The earliest reports of zinc-lead mineralization in the region include reference to samples collected at unknown locales by Eskimo prospectors (Anderson, 1944). In 1955 stratiform pyrite was discovered 19 km west of Red Dog by I.L. Tailleur of the U.S. Geological Survey (Tailleur, 1970). The first reported visit to what is known as Red Dog was by I.L. Tailleur in 1968, who was field checking a colour anomaly noted by B. Baker, a local bush pilot (Tailleur, 1970; Moore et al., 1986) ."

Jan 1, 1989

By Carlos Alberto Spier

The Águas Claras and Pico mines are two world-class, iron-ore mines hosted within Lower- Proterozoic banded iron-formations (locally known as itabirites) of the Minas Supergroup located in the Quadrilátero Ferrífero District, Minas Gerais, Brazil. The Águas Claras orebody consists of a 2,500 m long roughly tabular-shaped lens hosted within the dolomitic itabirite of the Cauê Formation. Dolomitic itabirite is the protore of the soft high-grade iron ore, which is the main ore type of the Águas Claras orebody, and represents more than 85% of the 284 Mt mined since 1973. Hematite is the main constituent of the iron ores. It occurs as martite, granular hematite and, locally, as specularite. Magnetite appears subordinately as relicts within martite and hematite crystals. Gangue minerals are very rare. These consist of dolomite, chlorite, talc and apatite and are especially common close to the contact with the protore. This virtual absence of gangue minerals is reflected in the chemistry of ores which are characterized by very high Fe contents (an average of 68.2% Fe). The Pico orebody is a continuous ~3,000 m long body of lenticular shape hosted within quartz itabirite, which is the protore of the soft high- and low-grade ores at the Pico mine. The soft high-grade ores, together with the low-grade ores, called iron-rich itabirite, are the main types of ores at the Pico mine, respectively representing approximately 51 % and 29 % of the reserves within the pit. The iron oxide mineralogy is the same as that of the Águas Claras mine, but in different proportions. Gangue minerals are very rare in the high-grade ores, but are slightly more common in the iron-rich itabirite. Quartz is the dominant gangue mineral, and is found with minor quantities of chlorite. The chemistry of the high-grade ores is characterized by high Fe contents (an average of 67.0 %) and low P, Al2O3, and SiO2 which are concentrated in the fines. Iron rich itabirites average 58.6% Fe and 13.5% SiO2.

May 1, 2003