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By D. J. Bowen

"Abstract -The Great Dyke extends for 540 km along strike, to unknown depth, and varies in width from 3 km to 11 km. Rb/Sr age determinations gives values of approximately 2470 Ma.The Dyke consists of a variety of mafic and ultramafic rocks, many altered to serpentinites. These include, from top to bottom, successions of gabbro/norites, pyroxenites, peridotites/harzburgites, and dunites/picrites.The layers dip in from either margin, steepest at the edges (20°) and flattening toward the central sections. Four separate complexes are present. From north to south these are termed the Musengezi, Hartley, Selukwe and Wedza Complexes, and are described as 'boat-shaped' or 'pig-troughed'. All are similar in petrological sequences. Physiographically, the Dyke is spectacular in the north, where as a mountain range it meets the Zambezi Escarpment. Elsewhere in the central parts there is little surface expression and wide open treeless vleis. Dyke rocks cut through granite and schist belt terrain and are termed 'The Magnesia Belt'.Vast mineral resources exist. These include chrome, asbestos, platinoids, nickel, copper and gold. Up to eleven chrome seams numbered from top to bottom occur in the lower ultramafic sequences. Seams are narrow at 10 cm to 30 cm but of high grade. The platinum occurs 10 m to 40 m below the norite/pyroxenite contact.A 60 m wide zone of Light Sulfide Mineralization (LSM) of Jess than 1% sulfides extends from the lower gabbronorites into the upper pyroxenites. In this LSM, four enriched zones carry up to 5% sulfides. The most widespread is termed the Main Sulfide Zone (MSZ), below which is No. 2, No. 3 and No. 4 Sulfide Zones. The MSZ carrying pyrite, pyrrhotite and chalcopyrite is a multi­ element ore with components of PGE (Pt-Pd-Rh), nickel, copper and cobalt, and gold and silver.Extensive exploration programs have been carried out and the intention is to begin large-scale mining. However, with Russia supplying metals to the western markets, South Africa's cutback on production, and an end to the Cold War, delays have arisen."

Jan 1, 1994

By John L. Mero

"The ocean has served humanity as a source of raw materials for thousands of years, but only on a minimal scale relative to its potential. Exploration programs have shown the ocean to contain a large number of mineral deposits of great extent and attractive grade. Recent research has indicated that a number of these deposits can be economically exploited with present-day technology and that the cost of winning many industrially important minerals from the oceanic deposits is potentially much less than that of winning similar minerals from land deposits. Although the finding of mineral deposits in the sea is a relatively simple matter at the present time, the exploitation of many of these deposits has lagged due to the lack of the availability of specific mining techniques for the individual deposits. Within the past two years, however, several developments have taken place in the design and testing of ocean mining systems in depths of water as great as 12,000 feet which indicate that the problem of mining in the ocean may soon be solved.Within the next decade, the ocean should prove to be a major source of many minerals for society and should come to dominate as a source of such metals as copper, nickel, cobalt, manganese, etc. Within a few years of the initiation of the mining of the deep-sea metalliferous nodules, land sources of such metals as nickel, cobalt, copper, manganese, etc. will be seriously affected and it is conceivable that the present structure of the world mining industry will undergo a substantial change in character."

Jan 1, 1972

By Gillyeard J. Leathley

The Cassiar Asbestos mine is situated on McDame Mountain in northern B.C. at a mean elevation of 6000 ft (1830 m), some 6 miles (9.6 km) from the townsite /mill complex. Asbestos ore production averages 1,200,000 tons at 9% R.M.G. (Recoverable Mine Grade) and waste production is 6,000,000 cu. yd annually. Waste is loaded by P&H 1900 AL 11-cu.-yd shovels and transported by 75-ton and 85-ton end-dump trucks to the waste dumps. The ore is loaded by a 992 Caterpillar 10-cu-yd front-end loader into 50-ton and 75-ton trucks, which transport it to the crushing plant located at the mine. The ore is transported by a 15,370-ft (4685-m) tramline to the mill complex.

Jan 1, 1978

By Carmen M. Neculita

Optimizing the long-term efficiency of passive systems for the treatment of highly contaminated acid mine drainage (AMD) is still a challenging issue. The optimization lies, among others, on improving the understanding and quantification of metal removal mechanisms in order to predict and enhance the stability of neo-formed minerals in secondary phases. Sorption, and precipitation as oxides-hydroxides, carbonates and bio-sulfides are likely the most important metal removal mechanisms involved in passive biotreatment of both slightly and highly contaminated AMD. In the same time, the preferred mechanism is precipitation of metal sulfides that are more stable and less pH dependent than carbonates and oxides-hydroxides. However, results of relatively recent research studies performed at laboratory scale showed that sulfides accounted only for up to 15% of total metals removed in passive bioreactors treating highly contaminated AMD dominated by iron (around 500 mg/L). Several approaches were used in the aforementioned studies to understand and quantify metal removal mechanisms in spent reactive mixtures collected from long-term (12-15 months) operating column bioreactors. These included: thermodynamic equilibrium modeling and various chemical extractions and mineralogical analyses (such as single and sequential extractions, acid volatile sulfides-simultaneously extracted metals determination, scanning electron microscopy, X-ray diffraction, and thermo-gravimetric analysis). The large proportion of metals (85%) removed by sorption and precipitation as oxides-hydroxides and carbonates suggests a relatively high mobility of the neoformed minerals, especially in low pH conditions. However, no data is available on the long-term stability of spent reactive mixtures and, on the implications for the sustainable management of this type of solid waste. Lately there is almost a consensus that the efficiency of highly contaminated AMD treatment is warranted by the use of multi-step passive systems, including both chemical and biological units, installed sequentially. However, very few well-documented studies are available on the design, construction, operation and long-term efficiency of these multi-step systems. A leading example is the tri-unit passive system installed on the abandoned Lorraine mine site (Québec) to treat a highly contaminated AMD dominated by iron (about 2,500 mg/L). This tri-step system (160 m3), consisting in two bioreactors separated by a unit filled with wood ashes, achieves to date a satisfactory removal of iron (up to 99%). Moreover, based on the data collected during laboratory testing, iron was mainly removed in the wood ashes unit (from around 3,200 mg/L to 10 mg/L) by precipitation of oxides-hydroxides as predominant mechanism and only partially by sorption. However, no data is available on the actual metal removal mechanisms in the field. Overall, theses multi-step systems are more complex and their long-term performance is even less predictable than the single unit systems. This paper presents the current knowledge and the research needs on metal removal mechanisms in passive bioreactors and multi-step systems for the long-term treatment of highly contaminated AMD. KEYWORDS

Aug 1, 2013

By W. G. Miller, J. D. Scott, D. C. Sego

ABSTRACT The influence of using different extraction processes (caustic versus non-caustic) on thethixotropic strength of oil sands fine tailings is examined, as is the influence of adding a coagulant tocaustic fine tailings. The thixotropic strength of fine tailings at large void ratios manifests itself as a bonding or gel strength that has been widely noted both in the laboratory and in the field. This gel strength has a significant influence on preventing the initial consolidation or settlement of fine tailings. Differences between the fine tailings’ thixotropic strength development are explained based on their physical and chemical characteristics.

Jan 1, 2010

By D. Perednis

Fuel cells with thin samaria-doped ceria (SDC) electrolyte films deposited onto an anode support using spray pyrolysis were fabricated. The SDC films were deposited onto porous NiO-YSZ substrates at deposition temperatures between 400°C and 450°C. The influence of process parameters such as deposition temperature, flow rate, type of salt and salt concentration on the quality of the film was studied. A smooth dense film was successfully deposited using the precursor cerium ammonium nitrate and samarium nitrate dissolved in butyl carbitol (33.3 vol.%), 2-methoxy-l-propanol (33.3 vol.%), and ethanol (33.3 vol.%) solvent mixture. A deposition rate of 125 nm/h was achieved.

Jan 1, 2005

By Sean McClenaghan

Significance Setting Size Production Value History of Discovery Zn and Pb at Austin Brook Brunswick Belt Exploration Discovery Hole Geology Structure Metal Zonation Directed Research Incremental Ores Precious metals Closure and Beyond Mining Remnants Tailings

May 1, 2013

By Frédéric Flament

The aim of this paper is to present the development of a data validation software as component of a commercial mass balance package. Data reconciliation through mass balance is basically an optimization problem constrained by the law of mass conservation. As any optimization problem solved with a modern and robust software application, erroneous information or starting point will always lead to a solution, whether it is realistic or not. Moreover, good information wrongly weighted by an incorrect error model will lead to the same bad ending. In an industrial context where competition requires accurate information, data reconciliation without validation can be disastrous and calls for data validation before and after reconciliation. The challenge in automated data validation resides in the development of general theoretical solutions. Until now, none has been presented and only partial solutions are available. The development presented in this paper incorporates some of these partial solutions. The integration of human knowledge into the application paved the way to a more general solution. The combination ?theoretical validation ? human expertise? proved to be flexible and reliable enough to be integrated in a commercial data validation package. Numerous examples though industrial applications are presented. These applications demonstrate the validation of raw measurements, user support in the development of error models and validation of reconciled measurements.

May 1, 2001

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

By Jennifer L. Durocher

The speciation of Uranium in silica-rich depositional layers in the proximity to uranium ore deposits was investigated using micro X-ray fluorescence (VESPERS beamline), X-ray Photoelectron Spectroscopy, Laser-Ablation ICP-MS, Scanning Electron Microscopy, X-ray diffraction and micro-Raman Spectroscopy. The heterogeneous Si-rich laminations contain micrometer-size inclusions of secondary uranyl-minerals. The U concentration in these layers range from several ppm to lower weight percent and the U 4f spectra indicate variable U6+ : U4+ ratios. Correlation between the concentrations of U and other metals (M) suggests the presence of M-U-bearing nanoparticles or species within the amorphous silica matrix.

Aug 1, 2010

By Jr. Fackler

The ionization potentials of gaseous Group 11elements are similar, with Au(0) being 1.5 eV greater than the next highest member of the group, Cu(0). The ionization potentials are all very much greater than the alkali metals, making these ?coinage? elements rather unreactive to chemical oxidation. Ionization from the first oxidation state shows a different pattern, with Ag(I) being the most difficult of the Group 11 ions to lose an electron. Gold(I) is noble and only normally oxidized in the presence of strongly coordinating ligands such as thiols or cyanide. Gold(I) compounds are 2-, 3- and 4- coordinate, with 3-coordinate species generally showing visible photoluminescence under UV excitation. Dinuclear Au(I) compounds with strongly coordinating S or C ligands can be oxidized to form isolable metal-metal bonded Au(II) compounds which are often readily isolable. Many have been structurally characterized. T he ease with which electrons are lost from closed shell dinuclear sp ecies (with anti-bonding M-M interactions) increases when metalmetal bonded compounds are formed. T his observation was made by our group with oxidative-addition studies of dinuclear gold(I) ylide complexes. It was superbly demonstrated recently by Cotton?s group who reported the isolation and characterization of a dinuclear closed shell transition metal species which is more readily oxidized than cesium. Trinuclear Au(I) pyrazolates, TR(pz), carb eniates, TR(carb), and benzylimidazolates, TR(bz), are well known and undergo electron loss through oxidative addition forming Au(I,III) mixed valence species and ultimately trinuclear Au(III) species. Au(II) species are absent from isolation in these oxidations. These carbeniates and benzylimidazolates also are excellent bases for metals ions such as Tl(I) and Ag(I). The acidic, neutral trinuclear compound [Hg(C6F4)3]3 also interacts with these bases. We have also shown that the neutral organic pi acids C6F6 and TCNQ form stacked pi-acid pi-base products with the trinuclear Au(I) compounds. In this paper, the structure of the octafluoronaphthalene acid-base product will be described. It displays a feature not observed previously in that the product is photoluminescent with a bright yellow emission. The 3.5 ms lifetime is very long and reminiscent of the long lifetimes observed by Balch for the stacked methyl,methoxy Au(carb). The electrochemical oxidation of tetragold(I) clusters, [Au4(form)4] have been studied in 0.1 M Bu4NPF6/CH2Cl2 at Pt working electrode at different scan rates. Three waves are obtained at 0.75, 0.95, and 1.09 V vs Ag/AgCl at scan rate 500 mV/s. The potential of the three reversible waves is independent of the scan rate in the range 50 mV/s to 3 V/s. The current at the third wave is larger than those at the first two waves. These tetranuclear species app ear to be effec tive catalyst precursors for the oxidation in air of CO. Introduction. The electronic structural relationships of the coinage elements and the alkali metals are similar in the sense that each have a [closed shell]ns1 configuration, yet their ionization energies (Table) and chemistries are clearly vastly different. The Group 11coinage elements have an underlying nd10 level immediately below the ns1 level. Unlike the alkali elements, ionization leaves the filled d electron shell the next accessible for further ionization. The coinage elements are all relatively ?noble?, much less reactive to environm ental conditions than the alkali metals. With the coinage elements, oxidation becomes very much dependent upon the types of ligand s availab le to bo nd to the ionized state.

Oct 1, 2003

By Rob Kelso

What is a Lunabot? ?Robot Controlled Remotely or Autonomously ?Visual and Auditory Isolation from Operator ?Excavates Black Point 1 (BP-1) Simulant ?Weight Limit - 80 kg ?Dimension Limits - 1.5m width x .75m length x .75m height ?Designed, Built and Tested by University Student Teams

May 1, 2013

By R. S. Bigelow

Part 1.- Metal Mines Early experiments with mechanical loaders in metal mines were confined largely to machines of the shovelling type and generally air-operated. Although the first application of the scraper to metal mines dates back to 1910, it was not until about twelve years ago that it came to be used extensively. Generally, the scraper gives better results in metal mines than in coal mines, as degradation due to soft bottom and breakage are not factors, but it has a wide range of application and is successfully used in the mining of salt, potash, gypsum, zinc, copper, and a variety of ores, from soft material to hard chunky ore which settles compactly. Today, the scraper has replaced to a large extent the shovelling type of machine in metal mines. Scrapers have offered an inexpensive solution for the mucking problem and are now employed in most mining districts throughout the world. They are operated by labourers of all colours and degrees of skill. Each installation, however, requires individual study on the part of the mine mechanical department to determine the type of scraper, horsepower of hoist, and most economical speed of rope, as well as method of rope rigging. Unfortunately, the scraper has no power to select pay ore from waste and its suitability for use under circumstances which might require sorting of the ore can only be decided by a weighing of the economic factors involved

Jan 1, 1931

By J. Oyunaa, P. Munkhbaatar, A. Sarnai

"The molybdenum mining process used at Mongolia Erdenet Company is a selective flotation of molybdenite from the copper porphyry ores in which the extraction of molybdenum comes as a byproduct of the ongoing copper production.The mineralogical composition of molybdenum concentrate is 99.4% molybdenite (MoS2), 0.09% molybdenum oxide (MoO3), 0.52% powellite (CaMoO4) and wulfenite (PbMoO4) and content 47.76– 47.92% molybdenum, 1.5–2.67% copper, 0.04% renium.From compared solvents sodium and carbonate and ammonia are like extracted molybdenum than hydrochloric acid, which contained 96.23–97.72 p.c. of its total amount. Hence to take into consideration abundance, cheap and suitable for analysis and processing the molybdenum concentrate ammonia is choosing as a basic solvent. By direct evaporation of ammonia extract solution, we obtained ammonium ortomolybdate, which contains 73.47% MoO3. INTRODUCTIONMolybdenum occurs in the earth’s crust in an abundance of about 10–14%, mainly as molybdenite, MoS2. Small quantities are also associated with other metals having similar chemical properties. Thus wulfenite (PbMoO4) is found in oxidized parts of sulfidic lead deposits in many regions of the world; powellite [Ca(Mo,W)O4] is a calcium molybdate usually formed from the modification of molybdenite in deposits containing tungsten as scheelite (CaWO4) and tungsten substitutes for molybdenum up to about 10%. Ferrimolybdite (Fe2Mo3O12·8H2O) is the product of oxidation of molybdenite in the presence of iron (III) compounds. Molybdenite is the primary source of molybdenum. Should demand for molybdenum rise so that additional sources become necessary, wulfenite, powellite, and ferrimolybdite may become commercially significant. Molybdenum ore is mined by underground and open-pit methods. A typical primary molybdenum ore body contains 0.05–0.25% Mo, and secondary ore bodies (copper porphyry ores) average 0.3–1.6% Cu and 0.01–0.05% Mo. Flotation remains the preferred and almost exclusive method of upgrading the molybdenite mineral to an industrial-grade molybdenite concentrate containing 90–95% MoS2, the balance being gangue (Habashi, 1997)."

Jan 1, 2016

By R. L. Stanton

"The present contribution examines, in some detail, what appear to be the three outstanding features of the field occurrence of the conformable ""pyritic"" deposits. These are their association with fragmental volcanic rocks (and derivatives), their occurrence in sediments of near-shore formation, and their highly variable structural associations.In a recent paper it has been suggested that two such ""pyritic"" de-posits in New Brunswick may have originated as marine concentrations of volcanic base metal and sulphur compounds, and that many of their present features are the result of diagenesis, folding, and regional metamorphism. This is now put for-ward as a general explanation for the particular class of deposit considered.Such deposits should, on this hypo-thesis, be regarded quite simply as an integral part of the particular geological environment in which they occur -as a normal, though minor, sedimentarry type developed, char-acteristically, in near-shore and shelf facies of intravolcanic units formed along the margins of eugeosynclines. They should not be considered -as, for example, is required by the re-placement theory -as later features simply superimposed on a geological situation to which they are genetically unrelated. Where they are associated with folds and other structures, this may be attributed, from one in-stance to another, to mechanical migration during folding, weaknesses induced by pre-existing sulphides, and, occasionally, to fortuitousness.In the light of this postulated origin, it is suggested that the first stages in regional prospecting for deposits of this particular class should be broadly palaeogeographical. Later phases of the search should then be directed to the delineation of sedimentary facies and, finally, to the investigation of geological structure."

Jan 1, 1960

By P. Harvey

"Following initial discovery in 1991, BHP Billiton Diamonds Inc. opened Canada’s first diamond mine, the EKATI Diamond Mine (EKATI) in the Northwest Territories on October 14, 1998. Four short years later, on November 29, 2002, saw the opening of North America’s first underground diamond mine, the Koala North mine. Nestled between the original Panda open pit and the new Koala pit, which is in the early stages of production, Koala North represents the only underground kimberlite mining venture in Arctic conditions outside the new underground mines being developed by ALROSA in the Yakutsk region of eastern Russia. Extensive underground kimberlite mining has been practiced in the Republic of South Africa for much of the 20th century and continues today.Underground mining represents a key component of the long-term business plan for EKATI. As various open pits reach their economic limit, continued recovery of high-value ore at depth is dependent upon the ability to productively mine the kimberlite pipes by underground methods. As a function of its location, size, and value, the Koala North pipe is ideally positioned to host the first underground mine at EKATI. Koala North is designed and approved as a learning mine, from which to gain valuable experience in preparation for the potential mining of other larger, higher value pipes by underground methods in the development, the Koala North mine is well into its production ramp-up phase and currently producing at around 1,200 t/day from the first two production levels."

Jan 1, 2005

By E. Trickey

In the mining industry there exists a constant drive for increased safety and productivity and decreased operating costs. This acts as a driver for implementing advanced technology. As more and more mining operations turn to new technologies, an observed bottle-neck for technology advancement has been the limitation of machine vision solutions available. LiDAR has been seen as a possible solution to the machine vision problem. In the past, a few studies on machine vision solutions have been undertaken by various groups involving scanning laser range-finders and millimetre-wave radar. These studies have done little more than highlight the limitations of both technologies in the mining environment. Little work has been done, however, exploring the applicability of LiDAR imaging technology for mining applications. Neptec Technologies Corp. has developed an obscurant-penetrating LiDAR (OPAL) sensor technology which overcomes the limitations faced by traditional LiDAR sensors when operating in a dusty environment, as well as advanced 3D real-time intelligence (3DRi) data processing algorithms that enable the real-time exploitation of 3D imaging data with sensors mounted on moving vehicles. Working with Teck Resources Ltd. and Barrick Gold Corporation, Neptec is adapting the OPAL sensors and 3DRi technology to mining applications. This paper highlights a number of real-time OPAL/3DRi based mining applications demonstrating how this technology overcomes the limitations of traditional LiDAR to provide a real-time machine vision solution that supports mine machine autonomy.

Aug 1, 2013

By R. R. Irrinki

Abstract -The Key Anacon deposit consists of four sulfide zones called, from south to north : Key Anacon No. 1, Key Anacon No. 2, Key Anacon No. 3, and Key Anacon Copper Zone. Massive sulfides of zones 1, 2, and 3 are underlain by rocks correlated with the Nepisiguit Falls Formation and are overlain by matie volcanic rocks correlative with the Boucher Brook Formation. In contrast to zones 1, 2, and 3, narrow northwesterly-trend.ing, copper-rich fracture zones occur within the Patrick Brook Formation. Sulfides in zone 2 occur as three mineralogical associations, namely: pyrite-chalcopyrite, pyrite-sphalerite-galerta, and pyrrhotite-sphalerite-galerta. The distribution of lithologies and en-echelon patterns of the three sulfide lenses of Key Anacon No. 2 zone are the result of F1 and F2 folding. Zone 2 is the most promising economically, with proven reserves of 1.11 million tonnes grading 0.2207o Cu, 3.47% Pb, 8.41% Zn, and 96 g/t Ag; the zone is open below a depth of 427 m.

Jan 1, 1992

By G. H. Robbins

"Originally presented at TORONTO 94, CIM-AGM, this paper has been updated to reflect the present status of business development for theSO2/AIR process. The paper reviews the back-ground leading to the invention, discusses the process chemistry and historically tracks the commercial development. Engineering and cost considerations are presented.IntroductionThe year 1994 was particularly significant in terms of the technical and business development of the INCO SO2/AIR cyanide destruction process. The year marked a decade of service to the world mining community since INCO acquired the Canadian patent in 1984. In that time period, the technology had become widely recognized as the state-of-the-art process in the field of cyanide detoxification and today we enjoy the distinction of having licensed the process at over 50 project sites worldwide. The application for the process has mostly been in the mining industry in precious metal recovery plants where it offers treatment for a wide range of waste streams such as: CIP/CIL slurries, Merrill-Crowe barren bleed solutions and/or re-pulped filter cakes, tailings pond water recycle or discharge, make-up water to flotation circuits and feed to underground backfill plants. The process also applies to the treatment of high cyanide rinsewaters from metal plating shops. More recently the process is being applied to the rinsing and abandonment of heap leach pads where it has proven to be a very cost-effective application of the INCO process. The distinct advantages that have led to the success of the process are the ability to work on slurries as well as solutions and the significantly low cost of sulphur dioxide products. The process is safe and easy to manage and uses all forms of SO2(liquid, gas or salts) which gives the process tremendous versatility with respect to geographic application. Having more than ten years of service"

Jan 1, 1996

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