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By Pierre Pelletier, Julie Fournier, Gianni Bartolacci, Yves Breau, Dominique Girard, Ahmed Bouajila, Carl Duchesne

"The development of on-stream analyzers (OSA), such as those based on X-ray fluorescence (XRF), has been key to improve metallurgical performance of flotation processes. However, since these analyzers are shared between several streams, they typically provide grade measurements every about 10-15 minutes. In general, this frequency is too long compared to process dynamics and so, implementing an efficient feedback control strategy based on OSA can be difficult. In addition, due to the limited capacity of OSA systems, several important intermediate streams are not analysed, but could provide relevant information about the state of a flotation circuit.To overcome this problem, vision systems have been developed in the past to predict concentrate grade based on froth color – this could be very useful to control flotation performance between OSA measurements. However, applications reported in the literature typically use univariate summary statistics of the full red, blue, and green color distribution of froth images, while RGB images are truly multivariate. Although, in some cases, grade prediction was achieved with reasonable accuracy, one may, by using only summary statistics, miss important information about the state of the flotation process.This paper investigates the application of Multivariate Image Analysis (MIA) concepts to flotation froth images. These techniques are based on multivariate statistical methods such as PCA and PLS, which have the ability to analyze large databases (such as digital images) and summarize the relevant information content of the data into a small number of latent variables, capturing the most important features of the images for concentrate grade prediction. The potential of application of these methods in the mineral processing industry is illustrated using a few industrial case studies."

Jan 1, 2003

By D. M. Doyle

"A study of the various components contributing to energy costs and their relationships to generally trended operating data, such as tonnage, operating costs, etc. over progressively shorter time periods provides information for an energy audit. A study of annual data gives some insight into the importance of various energy components. As the time frame of the study 11rogresses through monthly, daily and finally, into quarter hourly data, the variations become more evident and most important, strategies develop to minimize energy costs. The results of an audit conducted during the summer of 1978 at Wesfrob Mines are reported to illustrate this important phase, prerequisite to a meaningful energy cost avoidance program.The balance of the paper deals with the energy conservation program at Falconbridge Nickel Mines Sudbury Operations, the material and control equipment, the commitment, the new energy accounting practices and lastly, the policies. Examples of successful energy conservation endeavors include automatic peal electrical load control, waste heat recovery from mine air and compressor cooling water, energy reductions resulting from lower building temperatures and curtailmen: of idling loads. The use of pulse meters to measure the flow of gas, steam, compressed air and electrical energy, with their signals interfaced to process computers, allows monthly, daily and if necessary, immediate reporting of energy and energy per unit of production information. The program so reported at Falconbridge’s Sudbury Operations is credited with an annual cost avoidance of .9 million dollars in a 14.0 million dollar annual energy account."

Jan 1, 1979

By M. K. Mishra, U. M. R. Karanam

Relative to slender pillars, larger size pillars exhibit improved strata control. Fly ash, though traditionally treated as a waste product, is emerging as an alternate engineering material. This paper deals with the development of a strong fly ash composite material with additives. The geotechnical properties of this fly ash composite were determined and used to trap model core pillars, which resemble squat pillars. The trapped samples were tested under uni-axial loading in the laboratory and the results showed higher load-bearing capacity of the model core pillars. The reinforced fly ash composites provide lateral confinement and exhibit improved post- failure behaviour of the model cores.

Jan 1, 2008

By Yeonuk Choi, Gus Van Weert

"In regular CIL circuits, activated carbon is used for two purposes: avoiding solid/liquid separation after cyanide leaching, and minimizing gold losses in the tails. The carbon distribution and gold profiles in the successive CIL stages are operating variables, not objectives. When the CIL feed contains a preg robbing constituent however, such as native carbon, there will be competition for gold cyanide and this conflicts with minimizing of losses of gold to CIL tails. This paper examines some of the limitations of activated carbon in CIL circuits handling preg robbing Carlin Trend ores.INTRODUCTION Carbon-In-Leach (CIL) has been a great success treating regular gold ores, but the technology is still challenged by preg robbing feedstocks. Little information is available in the gold milling literature on CIL gold extraction from “free” milling gold ores which are preg robbing, or on autoclave discharge (POX’ed) slurries of double refractory ores. Neither feedstock is readily available for experimentation. No literature reference could be found describing deliberate modifications to CIL operations or CIL circuits due to the presence of two types of carbon: “native” and activated. There is some literature on the gold cyanide adsorption activity of native carbons (Schmitz, Duyvesteyn, Johnson, Enloe & McMullen, 2001). Various tests have been devised to measure this activity, commensurate with CIP and CIL practices (Tretbar, Arehart & Graves). In this paper, the term “native” carbon indicates (severely) preg robbing carbonaceous materials found in gold ores. There is considerable literature on the gold cyanide adsorption activity of man-made “activated carbons”. Various tests have been devised to measure this activity, commensurate with CIP and CIL practices. These tests are comparative, i.e. results relate to a standard carbon and depend on the test methodology and carbon history. The test results are equilibrium oriented, hence of limited value to CIL circuit designers or plant operators handling preg robbing solids; in CIL circuits most carbons are not loaded to capacity. Information on gold cyanide adsorption and desorption kinetics might be more relevant and that is one subject explored in this paper."

Jan 1, 2012

? Founded In 1953 ? Mining growth of 83% since 2007 ? We produced over 1 million ounces of Au in 2012 ? We Forecast of 20% Au production in 2013-2015 ? We have paid a dividend 31 years consecutively. Terry Reid ? 1992-93 Electrical Technical, College ? 1994-95 On the job placement College ? 1998 ? Licensed Millwright, ? 2005-12 ? Maintenance Reliability Planner ? 2012- Present Business Process Owner

Aug 1, 2013

By S. Schwartz, T. Bilney

"Over recent years a number of techniques have been developed as part of the AMIRA1 P9 project to represent mathematically or measure directly sub-processes occurring in flotation cells. These include the determination of:•,?a machine parameter (bubble surface area flux, Sb);•,?a froth parameter (froth recovery, Rf );•,?entrainment and drainage parameters (???and d); and•,?an ore floatability parameter (Pi).These flotation parameters allow the plant engineer to develop a model of the flotation circuit that can be used as a powerful tool to diagnose the performance of that circuit. The recently developed JKSimFloat V6 flotation simulator uses these parameters to predict the flotation circuit performance that would arise from changes in operating conditions and circuit configuration.This new flotation technology was applied to the Placer Kanowna Belle Gold Mine in Western Australia. A series of plant surveys, cell characterisation measurements and laboratory batch tests were conducted to determine the flotation circuit model parameters to be used within the JKSimFloat V6 simulatorA thorough flotation circuit analysis was then performed at Kanowna Belle using JKSimFloat V6. The recommendations that were provided by this circuit analysis have resulted in large improvements in the flotation performance at Kanowna Belle. These include a 1.3% increase in flotation gold recovery and a substantial decrease in operating costs. The analysis is still ongoing, however, the benefits already obtained from applying this technology have resulted in a US$1.3 million a year improvement to the mine."

Jan 1, 2005

By M. Drozd, A. Ibrado, P. Butcher

While effective in treating refractory sulfide ores, pressure oxidation leaves carbonaceous matter unscathed and able to adsorb gold from cyanide solutions. Barrick Goldstrike's strategy to mitigate this problem is to minimize contact between dissolved gold and native carbon in advance of the carbon-in-leach (CIL) process. Measures currently in use include limiting carbonaceous matter in the plant feed by meticulous blending of ore, controlling the degree of oxidation in the autoclaves and blinding native carbon surfaces with lauryl sulfate. The presence of residual cyanide and thiocyanate in the process water remains to be a cause of premature gold dissolution and loss of gold by adsorption on carbonaceous matter. This cyanide is introduced by water that is recycled from the tailing pond. Of several treatment options considered, oxidation by peroxymonosulfuric acid, also known as Caro's acid, is deemed to be the most effective. Laboratory and pilot plant tests show that Caro's acid can oxidize free cyanide, weak¬acid-dissociable (WAD) cyanide and thiocyanate, resulting in significant improvements in gold recovery downstream. The process requires Caro's acid at 125 % of the stoichiometric requirement and pH in the range of 9.5 to 10 to accomplish the desired destruction in about twenty minutes. A cyanide destruction plant is currently being designed and construction should be completed by the end of 2005.

Jan 1, 2005

By Leslie F. Sawatsky

Failure of drainage works is one of the principal threats to the sustainability of mine closure facilities but the risk can largely be remedied by appropriate design of mine closure drainage facilities. The feasibility of sustainable mine closure facilities that avoid failure of drainage systems needs to be established during the early stages of mine planning, before mine disturbances make sustainable closure uneconomical. Experience in mine development shows there is often enough latitude in mine plan development to incorporate measures with neutral economic consequence and positive environmental benefit. Project managers need to resist the temptation to develop mine plans and closure drainage plans independently. Integrated mine planning with effective inputs by environmental specialists and drainage designers may affect the overall mine configuration, footprint and schedule. Key issues pertain to the end pit location, waste dump configurations, pit infill elevations, fluid impoundments, diversion channel routing and preservation of flows to receiving waters. Guidelines with illustrations of suitable practices are presented to assist mine planners.

May 1, 2004

By D. Eastick, S. Hardcastle

"Over the last few years, a multi-faceted feasibility study has been evaluating the introduction of hydrogen fuel cell-powered equipment into underground mines to replaced diesel engine-powered equipment. The analysis has shown that under normal operating conditions fuel cells could at the very least be an environmental and health benefit by eliminating combustion engines and their unwanted by-products. However, they could also generate significant reductions in the amount of ventilation a mine needs to supply when compared to dieselized operations; this would further decrease a mine’s energy consumption, its associated greenhouse gas impact, and also reduce a mine’s significant ventilation-associated costs. Fuel cell-powered equipment also has the advantage of lower noise and heat production compared to its equivalent diesel-powered counterpart.The degree to which fuel cells can generate ventilation benefits in underground mines depends upon a number of operational parameters and mine specific qualifiers such as current ventilation control or management, mine depth, inherent dust conditions, and minimum velocity requirements.However, another major consideration in the introduction of fuel cells in underground mines will be the safety requirements associated with diluting and removing the potentially explosive hydrogen in the event of a gas leak. In outside surface applications, it is possible to use dispersion, buoyancy, time, and lack of ignition sources as mitigating factors in deriving a low risk of an explosion. However, in underground operations, these factors change, and dispersion and buoyancy are limited; time may not be available and, in non-coal mines, ignition sources are not typically controlled. When a hydrogen leak occurs, the availability of sufficient ventilation to dilute and effectively remove the gas will be critical. Consequently, ventilation may be the prime risk controlling factor. In this paper, the authors evaluate the potential benefits of replacing diesel engines with fuel cells in powered production equipment, discuss the mitigating qualifiers that could limit ventilation savings, and evaluate solutions to retain and maintain an additional ventilation capacity in the event of an emergency situation, such as a hydrogen leak from the fuel cell stack or its distribution system."

Jan 1, 2007

By R. F. Hochstein, A. J. Neale, B. C. Flintoff

"Process control technology holds very significant potential benefits for many mineral and coal processing plants. The impact can be expected in terms of performance improvements (e.g. increased throughput, better quality control, higher availability), through reduced operating costs (e.g. lower reagent consumptions, manpower reductions) and in the form of intangibles (e.g. reduced vulnerability to manpower turnover, increased productivity in the user group). However, the installation of a process control system will represent considerable capital expenditure and will generate an operating cost. No management team would approve the funding for such a project without some reasonable measure(s) of the profitability of a proposed system. This paper describes a methodology for addressing the justification problem. Of particular interest is the approach to quantifying performance improvements, frequently found to be the predominant benefit of process control.INTROPUCTIONProcess control has become widely recognized as an essential component of any processing operation. It has direct impact on productivity, process efficiency and product marketability. The reported pay backs associated with successful installations underscore this observation. As a consequence, many operators who have little in the way of process automation are looking to initiate control projects, while those who currently enjoy some level of automation are looking to upgrade existing control systems (= process + instrumentation + hardware + software + operators + support). While the emphasis here would appear to be on retrofit process control projects, new plants, or those currently in the design stage, will usually find themselves in one of these categories shortly after startup 1."

Jan 1, 1990

By Mark Rebagliati, John Payne, Jim Oliver

The Campo Morado precious-metal-bearing, volcanogenic massive sul?de deposits occurin a lower Cretaceous, bimodal, calc-alkaline volcanic sequence in a major northerly trending belt inthe Guerrero Terrane in northeastern Guerrero, Mexico. During upper Cretaceous to Early Tertiary greenschist-facies regional metamorphism, the rocks were deformed strongly into a northeast-verging fold-and-thrust belt. Three later stages of weak deformation were dominated, respectively, by kink folds, broad warps, and extensional faults. Most deposits occur in the upper part of a sequence of felsic ?ows and heterolithic volcanoclastic rocks or at its contact with overlying chert and argillite-sand-stone. The Reforma and El Rey massive sul?de deposits are on the overturned limb of a major, thrusted anticline, and the Naranjo and El Largo massive sul?de deposits are to the south on the upright limb of the same major fold. The La Lucha and San Rafael massive sul?de occurrences are in an upper plate to the southwest which was thrusted over the plate containing the Naranjo and El Largo deposits. In several of the deposits, Au, Ag, Zn, and Pb are concentrated near the stratigraphic top, andCu is concentrated near the stratigraphic base. Major minerals are pyrite, quartz, ankerite, sphalerite,chalcopyrite, and galena. Minor minerals are tennantite-freibergite, arsenopyrite, and pyrrhotite. Goldand Ag occur in argentian gold, and Ag also occurs in tennantite-freibergite. The cumulative inferred resource of massive sul?de for the Reforma, Naranjo, El Rey, and El Largo deposits exceeds 30 Mt, with the latter two deposits incompletely delineated. Underlying pyrite-quartz stockwork zones contain chalcopyrite, chlorite, and sphalerite. Hydrothermal alteration minerals in the stratigraphic foot-wall are pyrite, quartz, chlorite, ferroan dolomite, and ankerite. In the stratigraphic hangingwall, hydrothermal alteration minerals are sericite, calcite-dolomite, and lesser clay minerals and quartz. The deposits belong to a low-sul?dation, volcanogenic massive sul?de system formed in a subaqueous environment, and are of the bimodal, siliciclastic type.

Jan 1, 1997

By Mark Rebagliati, John Payne, Jim Oliver

Abstract-The Campo Morado precious-metal-bearing, volcanogenic massive sulfide deposits occur in a lower Cretaceous, bimodal, calc-alkaline volcanic sequence in a major northerly trending belt in the Guerrero Terrane in northeastern Guerrero, Mexico. During upper Cretaceous to Early Tertiary greenschist-facies regional metamorphism, the rocks were deformed strongly into a northeast-verging fold-and-thrust belt. Three later stages of weak deformation were dominated, respectively, by kink folds, broad warps, and extensional faults. Most deposits occur in the upper part of a sequence of felsic flows and heterolithic volcanoclastic rocks or at its contact with overlying chert and argillite-sandstone. The Reforma and El Rey massive sulfide deposits are on the overturned limb of a major, thrusted anticline, and the Naranjo and El Largo massive sulfide deposits are to the south on the upright limb of the same major fold. The La Lucha and San Rafael massive sulfide occurrences are in an upper plate to the southwest which was thrusted over the plate containing the Naranjo and El Largo deposits. In several of the deposits, Au, Ag, Zn, and Pb are concentrated near the stratigraphic top, and Cu is concentrated near the stratigraphic base. Major minerals are pyrite, quartz, ankerite, sphalerite, chalcopyrite, and galena. Minor minerals are tennantite-freibergite, arsenopyrite, and pyrrhotite. Gold and Ag occur in argentian gold, and Ag also occurs in tennantite-freibergite. The cumulative inferred resource of massive sulfide for the Reforma, Naranjo, El Rey, and El Largo deposits exceeds 30 Mt, with the latter two deposits incompletely delineated. Underlying pyrite-quartz stockwork zones contain chalcopyrite, chlorite, and sphalerite. Hydrothermal alteration minerals in the stratigraphic footwall are pyrite, quartz, chlorite, ferroan dolomite, and ankerite. In the stratigraphic hangingwall, hydrothermal alteration minerals are sericite, calcite-dolomite, and lesser clay minerals and quartz. The deposits belong to a low-sulfidation, volcanogenic massive sulfide system formed in a subaqueous environment, and are of the bimodal, siliciclastic type.

Jan 1, 1997

By Gregg S. Hill, Bert J. Huls

"This paper on coarse particle recovery (CPR) summarizes a process to capture coarse particles that are not recoverable by regular flotation. Several porphyry copper operations in the world operate analogous circuits that recover non-floated copper from tailings; however, the case presented here is unique in that extensive underlying test work has allowed us to elucidate some fundamental principles behind recovery enhancement. This paper discusses an overview of the flow sheet that is proposed to Minera Escondida Ltda., the nature of copper in the feed to the CPR circuit, and the various unit operations within the recovery circuit. Details of the technology behind each unit operation will be presented in later publications.INTRODUCTIONSince 1996 BHPBilliton and MEL (Minera Escondida Ltda.) have developed a process to recover copper from coarse particles in the rougher tailings. Copper recovery from fresh tailings is not new. Several operations in Chile, such as Chuquicamata, El Teniente (AMEC, 2003), Mantos Blancos and others have operated various forms of tailings circuits. Both Chuquicamata and El Teniente practice cascade flotation scalping off froth containing fine copper particles after allowing sufficient retention time, air inducement and, sometimes, additional reagent addition. Chuquicamata tailings are not segregated but floated in sequential cascade and conventional large cell arrangements. At the Valle Central operation of El Teniente a coarse fraction of mill tailings is ground and floated, with the rejects recombined with fine tailings and subjected to cascade flotation through a sequence of concrete launders as the tailings flow towards their final deposition area. Mantos Blancos cyclone the rougher tailings and blend the underflow with scavenger concentrate from elsewhere in the principal circuit prior to flotation in Wemco Cells. Kemess in BC, Canada operates a 160 m3 Outokumpu cell to reduce the tailings sulfur content (Rasmussen, et.al, 2004)."

Jan 1, 2005

By The Honourable George Prudham

"I AM PLEASED indeed to be present with you here today and to be taking part in the proceedings of your convention. You have been greeted and welcomed to the Province by Premier Manning who is also provincial Minister of Mines and Minerals, and to this City by Mayor Hawrelak. As Minister of Mines and Technical Surveys in the federal government and as Member of Parliament for Edmonton West, I have been asked to share the honour of extending greetings and a cordial welcome to all.It is a happy coincidence that this representative national gathering, indicative of the growing strength and significance of a great basic Canadian industry, is taking place in the Macdonald Hotel, the new addition of which marks another important step forward in the progress of this City and district.This happens to be the third national convention of the C.I.M. that I •have had the pleasure of attending and I trust that I am not presumptuous in expressing the hope that I will have the opportunity of attending many more conventions of the Institute in my present capacity.Dr. Kidd has bestowed on me a high honour by asking me to be Co-Chairman of this Inaugural Session of the Convention and thus to share with him the responsibility of presiding over the proceedings of this afternoon."

Jan 1, 1953

By D. M. Doyle

"In this paper I will summarized the Falconbridge Nickel Mines1) energy costs and consumption data by fuel, process, cost centre and estimate our future costs and consumption patterns 2) detail the distribution of electrical energy 3) distribution of other forms of energy 4) describe present and planned energy conservation schemes; and 5) discuss economic justification and responsibility.There is sufficient material in this presentation to warrant several technical papers, however we felt that an overview of all our data and endeavors on the subject, would be most beneficial to those companies formulating energy conservation plans. The data briefly referred to in this slide presentation can be found in the technical paper.Over a five year period, total energy costs will vary between $63 and $94 MM depending on the future rate of energy cost escalation. An unrealistic 32% reduction in energy consumption is required to hold our own in the years ahead whereas an attainable 10°;, reduction in energy consumption would save $9 MM over this five year period.Total energy consumption, tonnage of ore delivered to plants and their ration BTU’s per ton of ore, are graphed for the years 1973 through 1976 and forecasted for the 1980’s. In 1974 we along with other member companies of the Mining Association, determined our purchased energy per ton consumption rate and set, as our goal, a 20% reduction by 1980. The dotted lines calculated from the energy audit, based on 1976 data shows there is a potential for a 10% increase in energy per ton. This could result from a lower than forecasted mining rate and operation of the new roasting, electric furnace and acid recovery facilities installed for environmental considerations at designed capacity."

Jan 1, 1978

By G. Halverson, K. Blower

"Giant Yellowknife Mines Limited (Giant) has been producing gold since 1948. Located at Yellowknife, Northwest Territories, Canada, see Figure 1, the mine processes approximately 1,200 short tons per day of 0.23 ounce gold per ton of ore.The majority of the gold in the ore is sub-microscopic and associated within the mineral arsenopyrite. This association complicates the extraction method since straight cyanidation will only recover 30% of the gold. The operations at Giant involve four essential steps, with an overall recovery of 87%. The steps shown in Figure 2 are crushing and grinding, flotation, roasting and cyanidation. These processes result in a number of effluent waste streams characterized in Table 1. These streams are combined and sent to a tailings storage pond for subsequent treatment prior to discharge to the environment.Giant is located just north of the 62nd parallel where winter temperatures drop to -40°C for extended periods. This entails storing effluent in dams over the seven month winter period for treatment during the relatively short summer season.The treatment method currently employed at Giant is an ""alkaline chlorination-arsenic precipitation-flocculation"" process. The pond water is subjected to three phases of treatment prior to being discharged to the environment as shown in Figure 3."

Jan 1, 1987

By D Reddy Chinnasane

Outline Location of BirchtreeMine and Layout of 124 OB Cut and Fill Mining Background Purpose of the Studies Methodology Results and Analysis Conclusions and Recommendations

Oct 1, 2010

By V. Coffin, T. Cienski

"(Figure 1) Reagentized pulp enters into the column at about 1/4 of the distance from the top. Inside the column it meets with a downward flowing stream of water and with an upward flowing mass of air bubbles. Flotation takes place in this counter current system while at the same time fine gangue particles are washed off the froth before it reaches the overflow lip at the top of the column. The main operating features of the column flotation are as follows:a) No moving parts. Solids are kept in suspention not by an agitating action of a propeller but by settling down against the rising air bubbles.b) Wash water. Spray pipes are installed a few inches below the froth surface and deliver required volume of water. The purpose of this water is twofold:(i) it keeps in balance the flow of material through the column and(ii) it washes rising froth in the froth layer as well as removes unwanted fines attached to the bubbles at the lower flotation section. As a result the concentrate produced is of higher purity than in the conventional flotation. Column is characterized by very high up-grading. However, even temporary disruption of wash water supply results in a drastic drop of concentrate grate.c) Flow balance. (Figure 2) For the correct operation volume of the underflow (tail) is larger than that of the feed. The difference is made up by the wash water. This difference called bias is predetermined and ranges from some 4 to 15 USGPM depending on the size of the unit and process requirements."

Jan 1, 1981

By Tony Lipiec, Greg Gosson

"When it comes to new mines being developed, there is a general industry consensus that most low-hanging fruit has been picked. Many projects currently in the mine development pipeline have been around for decades, but were held back because of technical challenges. Future development of these deposits will likely require access to the public capital markets, and in Canada that means providing scientific and technical disclosure on these deposits in compliance with NI 43-101. As many of these “challenged” projects have metallurgical issues, the companies that own the projects need to ensure their metallurgical Qualified Persons provide transparent disclosure regarding proposed solutions to those issues.This paper provides an overview of the disclosure requirements under NI 43-101 that are pertinent to metallurgists, and other Qualified Persons who prepare technical disclosure regarding the metallurgical characteristics of a mineral project. It lists the triggers for a technical report under NI 43-101 and Canadian stock exchange policies, and identifies the sections of the report that should involve input from a metallurgist or process engineer. It briefly outlines new civil liabilities under Canadian securities laws that increase the possible consequences for not complying with the technical disclosure standards.These materials are provided for general information purposes only and do not constitute legal advice. Readers are advised to seek specific legal advice from their own legal counsel in relation to any decision or course of action contemplated."

Jan 1, 2003

By G. H. Hope

"Pamour Porcupine Mines of Timmins, Ontario operates two 3,000 ton per day concentrators which receive ore from eight to ten mines in the area. The area milling concept was adopted by Pamour in 1971 and has been used successfully since then. The purpose of this paper is to discuss the advantages and the problems of area milling. Pamour Porcupine Mines Limited operates two 3,000 ton per day concentrators which receive ore from eight to ten mines in the Porcupine region. The area milling concept was adopted as the route to survival for Pamour and has worked successfully. HISTORICAL BACKGROUNDProduction of gold from the Porcupine region in Northern Ontario started in the early 1900's and has been continuous since that time. Some of the major operators were companies such as Mcintyre, Hollinger, Dome, Pamour, Paymaster and the list goes on. An underground survey would reveal hundreds of miles of drifts and raises. The main group of mines extends from South East of Timmins to the Pamour Mine, 15 miles to the east. During the lean years of the sixties when gold prices were low, labour costs were rising rapidly, and ore grades were dropping, many of the area mines closed down their operations."

Jan 1, 1981