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By T. A. Lazier, C. S. Longley

"Paymaster Consolidated Mines, Limited, owns several groups of claims in various parts of the Porcupine district. The area in which mining has been carried on includes parts of lots 5, 6, and 7, con. 1, Tisdale township, and twelve adjoining claims in Deloro township to the south. Highway No. 67A between South Porcupine and Timmins crosses the property.The discovery of the Dome mine in 1909 caused a rush of prospectors to the district and in a few weeks practically all territory adjacent to the Dome was staked. At that time work was started on the West Dome, West Dome Lake, Apex, and Standard properties. These were consolidated in 1930 to form the present Company. Gold was produced from the West Dome Lake from 1915 to 1930, and from the Standard-Paymaster from 1922 to 1928. The total production of the previous and present companies from 1915 to November 30, 1946, has been 487,170 oz. gold and 149,342 oz. silver from 2,337,554 tons of ore."

Jan 1, 1954

By D. G. Dixon

A novel technology for leaching copper from primary copper concentrates has been developed at UBC. This patented technology takes advantage of the galvanic couple between pyrite and chalcopyrite to ensure rapid and complete oxidation of chalcopyrite under mild conditions in acidic iron sulfate solution, without the need for microbes, ultrafine grinding, or chemical additives such as chloride, nitrate, or surfactants. Copper recoveries of 98% or greater can be achieved at 80°C under atmospheric conditions in as little as 4 hours of residence time. The process is selective for chalcopyrite over pyrite, generates near-quantitative levels of elemental sulfur, and is fully compatible with conventional solvent extraction and electrowinning of LME Grade A copper cathodes. In this paper, the fundamentals of the Galvanox ? process are reviewed, and selected results of batch leaching tests on various concentrate samples are presented and discussed.

Jan 1, 2007

By Q. Ricoux, F. Goettmann, A. Maihatchi

"Electrodeposition processes are widely used in the metallurgical industry to produce, extract and refine metals from various feed materials. However, raw materials used to provide non-ferrous metals often contain high amounts of iron. In the presence of iron, while metals are plated at the cathode, electrowinning processes produce corrosive and highly oxidative ferric ions at the anode that are harmful for the process sustainability. In fact, these ferric ions cause dramatic current efficiency loss, induce high maintenance expenditures to limit the corrosion of devices and it results in the formation of impure and dendritic deposits on the cathode. Consequently, the management of iron in electrodeposition process became a major issue in non-ferrous metals production. Actually, numerous methods have been developed to limit the ferric ion concentration in the electrolyte or, at least, to limit its harmful effect. Many methods aim to limit the iron(III) concentration in the electrolyte, generally by coupling electrowinning to extraction process such as solvent extraction (SX) (Bender & Emmerich, 2015), ion exchange (IX) (Gula, Dreisinger, & Horwitz, 1996) or cementation (Kust, 1979) processes to remove ferric ions. Other routes consist of (i) using the ferric ions oxidant properties to leach raw materials, either directly in the electrolytic cell (Fanta & Tributsch, 1975) or through a secondary circuit (Cain, 1950), or (ii) reducing ferric ions through periodic reversal of direct current to enhance the formation of Fe2+ (Loutfy & Bharucha, 1980). On the other side of the spectrum, papers discuss methods to valorize the iron from by-products of the non-ferrous metal industry, that generates vast quantities of iron containing wastes (A. Agrawal, Sahu, & Pandey, 2004). Many studies on iron electroplating and electrolytic iron production from ores have been carried out (Cain, 1950; Mostad, Rolseth, & Thonstad, 2008), but very few have been conducted on waste or by-products. Therefore, we propose to build on the previous literature review to develop a process for the production of electrolytic iron from by-products.INTRODUCTIONNon-ferrous metals and their alloys are used in a large variety of applications. Aluminum and titanium are used for their strength, light weight and corrosion resistant properties in structural applications. Copper has been used in various applications requiring high thermal and electrical conductivity, as kitchen products and electrical wires. Nickel and zinc are commonly used as plating materials; nickel offers a wide range of working temperature and zinc is used for steel plating. Gold, silver, and platinum group metals are used in electrical/electronic applications, jewelry and chemistry as catalysts."

Jan 1, 2016

By R L. Cheesman

An extensive Precambrian iron-formation lies about 2,000 ft. beneath post-Precambrian rocks in the Fort a Ia Corne Forest Reserve, south of Choiceland, Saskatchewan. The geology, deduced from limited drill results and from some geophysical observations, indicates that the deposit is a characteristic magnetite iron-formation, not uncommon in the exposed Precambrian of Saskatchewan, but also shows certain interesting features of faulting and pre-Paleozoic weathering which have given rise to a pre-served detrital deposit of hematite. The body is of ore grade and of sizeable proportions. T HIS paper is presented in order to set forth the interesting geological features of a Precambrian iron deposit located beneath the cover rocks of the Great Plains region and to comment upon the methods of discovery and interpretation of the nature of the body. The Choiceland iron deposit is located in the Fort a Ia Corne Provincial Forest Reserve, some 15 miles south of the town of Choiceland, Saskatchewan. Choiceland is

Jan 1, 1964

By Russell McIntosh

"The Madsen mine is in the southeastern part of Baird township, in Red Lake area, Ontario. It lies about 6 miles southwest of the town of Red Lake, with which it is connected by an all-weather road.The Madsen Red Lake Gold Mines Company was formed in March, 1935, to take over the holdings of the Falcon Gold and Jomac Gold syndicates. During 1935 an4 the early part of 1936 No. 1 shaft was sunk and drifts driven on four levels, all on a narrow quartz vein in a granite dyke.In July, 1936, the Austin zone was discovered about half a mile north of No. 1 shaft by Austin McVeigh, a prospector employed by the Company. Diamond drilling showed that the zone included an orebody worth development, and in 1937 No. 2 shaft was sunk, three levels opened up and sufficient ore outlined to justify the installation of a mill. Milling commenced in August, 1938, at the rate of 300 tons a day, which was later increased to 400 tons a day.The total production from 1938 to 1946 was 1,116,307 tons from which gold and silver having a value of $9,949,010 were recovered. The gold produced ranged from a minimum of 0.1910 oz. a ton in 1939 to a maximum of 0.2827 oz. in 1944. The average grade in 1946 was 0.2345 oz. to the ton."

Jan 1, 1954

By Donald F. MacDonald

METAL PRICES RISE WITHIN the past nine months, the mining industry of the world has been revivified by a spectacular price advance for the metals. ln fact, practically all geological raw materials have been marked up during this period. Reviving industry started the price rise, but the armaments race among the nations has intensified it. These factors, coupled with our decided building shortage, which must be made up, will probably maintain metal prices at decidedly favourable levels over the next two or three years, or longer. OUR MINERAL CIVILIZATION It is interesting to recall that in the past hundred years, while the white population of the world increased some three ta three and a half fold, the consumption of minerals increased seventy-five fold. In other words, ours is a mineral civilization. If we disregard short slumps, which we will occasionally experience, it seems certain that the bread upward trend in mineral consumption will be maintained for many decades into the future. Nations without reasonably abundant and diverse mineral deposits will eventually become nations without much power. Canada is blessed with a splendid store of minerals. Its mineral industry is now facing an exceptionally rosy future. What of the mineral industry of Nova Scotia? GEOLOGICAL RESEARCH ALLOWED TO LAG RN NOVA SCONA Many years ago, when geological science was in? its infancy, much geological study was carried on in Nova Scotia. In 1827, Francis Alger began work on the iron ores in the Bay of Fundy region. In 1886, E. R. Faribault began his series of remarkable papers on Nova Scotia geology. Between these dates, many others published papers on the geology of the Province. The most outstanding of this early group of geologists was Sir William Dawson, whose published works on Nova Scotian geology extended over the period from 1845 to 1891.

Jan 1, 1937

By J. D. R. Neilsen

The objective of the research conducted and presented herein was to determine the effect of pre-established free gas saturation on the sweep efficiency of an isolated inverted five-spot well pattern. The investigation concluded that the ultimate recovery of an isolated inverted five-spot may be slightly increased by establishing a free gas saturation prior to water flooding; however, of more significance is the extreme deviation of the pattern's performance after water break-through from that commonly obtained from developed well patterns. The rapid "water-out" characteristic common to both linear floods and floods conducted in developed well patterns was not evidenced in the isolated inverted five-spot. Instead, the wells continued to produce oil long after breakthrough until ultimate areal sweep efficiencies of four, five, and six hundred percent were obtained prior to the water-oil ratio becoming excessive.

Jan 1, 1962

By Lionel A. York

This paper outlines the type of water-bearing formations encountered in the Prairie Sediments and describes a method for effectively sealing these zones in order that shaft-sinking operations may be carried out with safety. Details are given of the procedure for carrying probe holes ahead of the shaft bottom. These probe or grout holes are employed for establishing a series of overlapping grout covers around the proposed shaft excavation to safeguard against large inflows of water during sinking. The pattern and length of grout covers cannot be standardized, and each cover needs to be specially designed to suit the varying ground conditions. In order to provide effective protection through the Prairie Sediments, the number of holes in any one cover would not be less than 8, and possibly as many as 64 would be required in certain zones. The length of covers would vary from 100 ft. to 250 ft. Emphasis is placed on the need for obtaining accurate geological and water information from exploratory holes, drilled in the shaft vicinity, in order to effectively plan all grout covers.

Jan 1, 1964

By Paul Delottinville, Maynard Hall, Henry Hillier

"An expert system application for supervisory control and optimization of the indurating process at the Iron Ore Company of Canada (IOCC) has been developed and installed in closed-loop. Prior to the installation of the expert system, the indurating machine was rebuilt and the instrumentation revamped. A Foxboro I/A Distributed Control System (DCS) was installed for regulatory control, and a new control strategy configured. The modernization of the regulatory control has resulted in significant improvement in both production rate and product quality. Expert system control was implemented in September 1996. Preliminary indications are that the expert system has further improved the consistency of product quality, enhanced fuel efficiency and increased productivity. The expert system considers both wet and dry sections of the circuit, and its optimization scheme is driven by pellet tumble index and compression strength. Statistical Process Control (SPC) rules were implemented in the expert system as part of the quality analysis and control scheme. The expert system application was developed and delivered using the Comdale Expert Optimizer (CEO), and has been in continuous closed-loop control since its installation. The system development and implementation is described, and preliminary benefits are presented..... IntroductionIn early 1996 the Iron Ore Company of Canada (IOCC) contracted Comdale Technologies of Toronto to develop and implement a real-time expert system for optimizing the indurating pelletizing furnace at our plant location in Labrador City, Newfoundland.The decision to install the expert system has been timely. Like many other resource-based industries in increasingly competitive markets, IOCC recognizes the need to find ways to improve the efficiency of our production process and ensure that product quality is maintained at the highest levels. With the Labrador City plant producing 11 million tons of iron ore pellets annually, implementing the best technology solutions to meet these objectives is critical."

Jan 1, 1998

By R. W. Boyle, W. Dyck

"Scientists throughout the world have observed radioactive disequilibrium in the uranium decay series. Radiometric and fluorometric determinations of U in plants from the Goldfields district and in sediments and rocks from the Beaverlodge district exhibit marked radioactive disequilibrium. The eU/U ratio in plants rooted in mineralized ground shifts from greater than unity to less than unity for those rooted in background soils. A similar shift is observed in the transition from rocks to stream sediments and to lake sediments in the Beaverlodge district.Results of a Rn-Ra-U survey of lake bottoms in the Key Lake district show that anomalous hydromorphic U from U mineralization is parallelled by anomalous Rn, even though there is much less Ra in the lake-bottom sediments than one would expect from the amount of U present. IntroductionDisequilibrium in the U decay series has been studied for many years and is observed in almost all surficial environments. Rosholt (1959) measured U, 234Pa, 23O'fh, 226Ra, 222Rn, and 210Pb in a large number of U ores and outlined six types of situations to explain disequilibrium. Davy (1974) outlines the geological significance of radioactive disequilibrium situations with respect to exploration. Levinson and Coetzee (1978) discuss possible mechanisms by which separations of parent and daughter elements are affected and suggest analytical pitfalls that may be encountered in the use of radiometric techniques when disequilibrium has occurred. Generally, it is the oxyphile and easily complexed parent 238U (with its associated isotopes 235 U and 234U) that is leached from rocks and soils at a faster rate than are the daughters, 230Th, 226Ra, 2loPb, and 206Pb. This mobilized U is adsorbed on sediments in streams and lakes, or enters groundwaters, where it is eventually precipitated under reducing conditions, occasionally in oregrade concentrations. This surface leaching and"

Jan 1, 1980

By F. Romero

In the last four years, Compañia Minera Doña Ines de Collahuasi has been working in the application of advanced multivariate statistical techniques for the improvement of the metallurgical processes. In this paper the main conclusions for the application of multivariable analysis to the EW process are presented; including the identification of (target) process patterns according to throughput and quality criteria. Based on the process patterns, process variables hierarchies were identified by selecting the most influential ones, as well as to identify and isolate the root causes of pattern deviations and sub-standard operating conditions, cause-effect relationships were established, leading to the definition of process policies and controls to give early corrections to potential failures. The analysis was focused on cathode quality, specifically in its sulfur content, using an empirical model based on those variables that from a phenomenological and statistical stand point appeared to be the most influencing ones.

Jan 1, 2007

By M. G. Rylatt, G. M. Popplewell

"Production from Canada's first diamond mine is planned for the last quarter of 1998. The climatic conditions and the variation in kimberlite types to be treated have lead to the development of a compact and flexible processing plant.High kimberlite moisture contents and winter temperatures below -40°C have dictated a process flowsheet with limited in-circuit storage to reduce materials handling difficulties. The latest developments in High Pressure Grinding Roll technology will be used to liberate the valuable diamond, reduce diamond breakage, and increase fines production to reduce the amount of material for down stream processing in the Heavy Medium Separation section.A varying heavy mineral concentrate yield has lead to the development of a final Recovery section that will incorporate Attrition Milling and Wet High Intensity Magnetic Separation for concentrate reduction. The latest developments in diamond X-ray sorting will be used to produce a final diamond concentrate for mechanical sizing, weighing and packing.Fine tailings thickening will utilise Deep Bed Compression type thickeners. This relatively new technology can produce;i) high underflow densities at low flocculant dosage rates, andii) clear overflowswith a smaller thickening area than conventional high-rate thickeners."

Jan 1, 1998

By E. S. Moore

Introduction The geology of the Sudbury nickel field has been studied extensively, but there are few reports dealing with the structure of the interior of the basin. It was not until the Treadwell-Yukon zinc-lead deposits were discovered that attention was strongly directed toward the large-scale faulting that has split the basin parallel to its long axis. This faulting has been responsible for the , ore deposits in the basin and it may be regarded in many ways as the most important geological event, next to the intrusion and differentiation of the nickel eruptive sheet, that has occurred in the Sudbury region. The early reports on the nickel region by Bell, and Barlow, were chiefly concerned with the nickel-copper ores and with the formations of the region. Coleman was the first geologist to map the nickel eruptive as a continuous sheet around the belt and to emphasize its basin character. On the map accompanying his later report, he shows an important offset in the nickel eruptive at its southwest end, where the large fault cuts this portion of the basin, but the fault was not traced into its interior, as little detailed work was clone in the basin at that time. No ore-bodies had been developed outside of the nickel-copper deposits associated with the norite when the map was prepared, and attention was mostly concentrated on the nickel eruptive. Coleman did, however, map and name the various formations found within the basin and, in general, his delineation of these has remained the standard for prospectors and other workers in the field until the present day.

Jan 1, 1930

By W. R. Lindsay

Considerable attention has of late been given to the blasting of large amounts of ore in one operation, on account of the saving in labour and explosives and consequent low cost per ton, and also on account of the additional safety to employees. The blast here described, at the Hidden Creek mine. at Anyox, B.C., is not necessarily unique either in size or methods employed, but some interesting p10blems were encountered and the solutions of these may be of interest to others engaged in similar work. The ore consisted mainly of old scope-bottoms and sill pillars, although there also were some braces and parts of vertical pillars included. Some of the stope-bottoms were overlain by caved waste, and one of the problems was to break them in such a manner that the maximum amount of ore could be recovered without serious dilution with waste. The ore blocks, designated as the 385 silt and the 7 A-103 blocks, were under preparation for blasting for over a year, as conditions permitted. This work consisted in drilling long machine drill holes, varying in length from 14 to 20 feet. These holes were drilled with the Numa detachable bit, made locally, starting at 2~-inch diameter and bottoming at 2 inches for the longest length. The long hole drilling was used in the thinner sections of the area. For the stronger, thicker portions, powder drifts (3 ft. by 4 ft. in section) were driven for the powder charges. Reference to the plan and sections (Figures 2 co 8 inclusive) show the relative location of these, as well as the long drilling. The amount of explosives used in the powder drift charges averaged 0.25 pounds per ton of estimated burden, varying from 0.2 to 0.3 pounds per ton.

Jan 1, 1934

By A. J. Pearce

MOST mines have a model of some kind to illustrate either geological structure, mining operation, or some special condition or feature of the property. The type used depends on the particular feature or use for which it is intended. At Dome Mines we have developed an interesting and practical application of the horizontal-type model. This model shows the workings of each level horizon plotted on glass. These glass panes are set in frames which, in turn, rest on drawers equipped with rollers which can be pulled out as desired into a light chamber. The features of this model are its rigid steel construction and that any desired number of level plans can be pulled out, eliminating any other interference from other levels. Figures 1 and 2 are photographs of the model cabinet and show its construction and general features. The cabinet is of steel construction with the following overall dimensions: width, 6 ft. 5 in.; depth, 6 ft. 7 in.; height, 5 ft. 2 in. When not in use it can be completely closed-in, making the cabinet practically dustproof. There are 30 drawers, one for each of the 29 levels and one for the surface. The glass in each drawer is divided into two panes, 36 in. by 36 in., of flatdrawn double-diamond 'lustraglass' with about l/32 in. between adjacent edges. The panes are held rigidly in the frames, which are lined with felt strips, and may be adjusted by set screws, four of which on each drawer are shown in Figures 1 and 2. The level workings, on a scale of 1 inch equals 100 feet, are traced in ivory black Windsor & Newtons artist oil paint. Co-ordinate lines are shown in crimson lake, and main geological contacts are shown in their respective colours. Figure 3 is a photograph looking down on one of the levels. The lighting consists of 14 30-watt fluorescent bulbs, with reflectors, under frosted glass. These lamps are much more satisfactory when operated by 60-cycle rather than 25-cycle and, as we had available nearby a source of direct current, this was used. The electrical unit consists of a rotary converter from d.c. to 60-cycle. This arrangement gives perfect lighting, allowing most colours to be easily distinguished. Figure 1 was photographed using this source of light, Figure 2 using an outside floodlight.

Jan 1, 1945

By K. E. Waters, C. Marion, T. Grammatikopoulos, A. Jordens

"The Nechalacho deposit, located in the Northwest Territories, Canada, is a heavy rare earth element (REE) deposit. The main REE-bearing minerals in the deposit are zircon, allanite, bastnäsite, synchysite, columbite (Fe) and fergusonite. Previous work investigated the use of gravity and magnetic separation in the processing of this ore and showed that coarse particles following grinding were enriched in zircon, suggesting the potential for selective comminution. The current work investigates the possibility to selectively comminute gangue minerals and concentrate REE-bearing zircon into coarser size fractions. The ore was ground wet in a laboratory rod mill for various lengths of time (0, 10, 20, 30, and 40 min). The resultant products were analyzed using ICP-MS, to determine the distribution of zirconium and REEs in the different size fractions produced after grinding, and QEMSCAN, to identify mineral phases, mineral liberation and the distribution of minerals. Optimum grind sizes for the upgrading of zircon due to selective comminution were then proposed, and dense medium separation was investigated as a means to further concentrate zircon.It is important to note that this process is not representative of the currently selected process design or recovery for the Nechalacho deposit. Any application of this process to this deposit would require optimization in order to ensure appropriate grade and recovery targets are met.INTRODUCTIONThe rare earth elements (REEs) are the fifteen elements in the lanthanide series of the Periodic Table, as well as yttrium (scandium is excluded in this work). Traditionally, REEs are categorized into two groups: the cerium sub-group of “light” rare earth elements (LREEs); and the yttrium sub-group of “heavy” rare earth elements (HREEs) (Golev et al., 2014). The LREEs comprise the first six lanthanides (lanthanum through samarium) and the HREEs comprise the remaining nine lanthanide elements (europium through lutetium) coupled with yttrium (Golev et al., 2014). HREEs are much less abundant in the earth’s crust and on average are more expensive than LREEs (Seredin, 2010). Of the fifteen REEs, the production of neodymium, europium, terbium, dysprosium and yttrium has been determined to be most critical due to their scarcity, high demand and criticality in many high-technology and clean energy applications, such as in illuminated screens for electronic devices and permanent magnets in wind turbines (Seredin, 2010; U.S. Department of Energy, 2011). These five elements are classified as critical rare earth elements (CREEs) (U.S. Department of Energy, 2011)."

Jan 1, 2016

By H. C. Cooke

Those who have followed the geological developments in connection with the copper deposits of Quebec will recall that on many properties the sulphide bodies occur as replacements of fault breccias or tuff breccias, and exhibit a pronounced distaste for the more massive lavas. At the same time the rocks around the ore-bodies are profundly altered, first by addition of silica and sericite, later by conversion of these minerals into chlorite. It has been known for some years that at the Amulet and Waite-Ackerman Montgomery mines these conditions do not prevail. At both mines the ore-bodies are replacements of massive lavas, and at the Amulet they are associated with a very peculiar rock christened ?spotted dog', or 'dalmatianite'. Accordingly, when in 1929 the writer had the opportunity to make a further examination of these properties, two problems presented themselves for solution. The first was to determine, if possible, the conditions under which massive lava, rather than breccia, is replaced by the sulphide masses; the second, to find out the exact nature of dalmatianite and its relations to the sulphide bodies. The first of these problems is believed to have been solved; the second has been found very complex, and will require further work before it is satisfactorily settled.

Jan 1, 1930

By M. Schwarze

SMS Meer GmbH with its COPPER PLANTS DIVISION produces a full line of systems and machines for the processing of copper. The product range includes: shaft melting furnaces, anode casting lines, horizontal and vertical casting lines, casting and rolling lines for copper wire rod and strip, cold pilger mills, planetary rolling mills as well as tube drawing equipment. The new designed shaft furnaces are the most economic way of copper melting. The CONTILANOD® system with hydraulic shear represents a breakthrough into higher production capacities and improved geometrical accuracy of anodes. The new generation of CONTIROD® lines with individual drives of rolling stands guarantee cost effective production of highest rod quality. A new horizontal continuous casting technology for the production of tube shells as feed stock for the copper tube manufacturing process ? directube® was developed and introduced into production. A first line for continuous vertical strip casting - called VERTICAST® - for higher production rates and improval quality of cold-rollable strips is in the final stage of commissioning. These innovative technologies increase product quality, reduce process costs and help for a wide use of copper in all sectors of life.

Jan 1, 2007

By M. A. Cawley, J. W. Jordan

"IntroductionTHE ORE PILLARS in the lower ""A"" ore body of Waite Amulet Mines, Limited, can be divided into two groups, those mined in the open by sub-level blast-hole methods, and those to be mined .against coarse rock fill. Of the three pillars in the last group one has been mined and is dealt with in this paper. The method of mining pillars against coarse rock fill was suggested by the late Dr. Oliver Hall, who was Consulting Engineer for the Company when recovery of No. 2 East pillar was being planned.HistoryThe Waite Amulet mine is in northwestern Quebec, nine miles north of the town of Noranda. The property is approximately three miles long by one mile wide. The present Company, which was formed by the amalgamation of Amulet Mines, Limited, and Waite Ackerman-Montgomery Mines, Limited, commenced operations in the summer of 1937. In the fall of 1939 a new .flotation mill was erected with a capacity of 1,200 tons per day, which was increased to 1,800 tons per day in 1943. The mill is presently operated at 1,400 tons per day.To date, seven orebodies have been found, the major ones being Lower A, East Waite, and Waite. Three separate concentrates are produced, copper, zinc, and pyrite. Total tonnage mined to the end of 1954 from all orebodies has been 7,340,000 tons, which averaged 4.6 per cent copper, 5.3 per cent zinc, and 0.037 oz. gold and 1.27 oz. silver per ton."

Jan 1, 1955

By D. S. Campbell

THE chief factors influencing the decision to build the Big Missouri mill underground were the topography of the country and the climate. The location underground assured certain saving in the cost of operation, such as the hearing of the mill, shovelling snow, and handling ore, which, over a period of time, would offset the greater initial cost of the mill excavation and machinery installation underground, as compared with the cost of a like plant on the surface. At Gilman, Colorado, where conditions are somewhat similar, the Empire Zinc Company, at their Eagle mine, are treating their lead-zinc ore in a mill built entirely underground. Company officials made a study of this plant before proceeding with the mill at Big Missouri. LOCATION, CLIMATE, TOPOGRAPHY The Big Missouri mine is situated on the Upper Salmon river, 22 miles north of Stewart, B.C., which is at the head of Portland canal, a narrow natural channel which penetrates 100 miles inland from the coast into the Coast Range mountains. Stewart, the distributing centre for the district, is about 600 miles north of Vancouver. The Big Missouri claims lie on and down the sides of the Big Missouri ridge, which extends north and south between the Salmon River and Cascade Creek valleys. The ridge rises to an elevation of 3,600 feet, is about half a mile wide, and to the east slopes down to the Joker flats in Cascade Creek valley. The Big Missouri camp is located on the flats at elevation 2,800 (see Figure 1). Preliminary development of the property took place from this point with an adit driven under the ridge. The western side of the ridge slopes steeply down to the Salmon glacier at elevation 1,900. Ore found on the 2,850 level extended down, and, in order further to explore the ore-body, the 2,850 level was driven through to the west side of the ridge, a surface incline tramway was built, and a lower tunnel driven at elevation 2,350, five hundred feet below the original 2,850 level, from the west side of the ridge. This tunnel development avoided the necessity of sinking, which would have been costly, as the mine makes a great deal of water (see Figures 1 and 2).

Jan 1, 1938