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By A. H. Lang

"IntroductionMUCH PROSPECTING, exploration, and development work was done for uranium in Canada in 1952, chiefly in northern Saskatchewan and in the Great Bear Lake region of the northwest Territories. The outstanding feature of the year was the great amount of work done in preparing for production at the Ace mine of Eldorado Mining and Refining, Limited, in the Goldfields region . of Saskatchewan. Many private companies and prospectors were also active in this region. Most of the other parts of Canada where uranium has been found received less attention than during the last few years, partly because so much interest was taken in the Goldfields region.In presenting this short summary of the year's activities now, the writer is handicapped because the season is not yet over; some discoveries have probably not yet been announced, and there has not yet been time to digest the numerous reports that have been sent in by companies and prospectors. In any case it would be impossible to give details for most of the discoveries and properties, because that would require a long report, and because that information is classed as confidential until released by the discoverers and companies concerned. It is only possible, therefore, to give a few generalizations, a brief out-line of the activities in northern Saskatchewan, even briefer ,accounts of the work in other parts of the country, and a few details that property owners have informed the writer he may publish or that have already been published by the owners."

Jan 1, 1953

By Cheowchan Leelasukseree

Mae Moh mine, operated by Electricity Generation Authority of Thailand (EGAT), is the largest open pit mine in Southeast Asia. Its production is approximately 15 million lignite tons and 90 million m3 of waste, annually. The bottom of the final pit limit is designed to be approximately 500 m in depth. Presently, the pit depth is almost 250 m below original surface. The complexity of geological structures, such as faults, has caused a number of geotechnical difficulties. In a challenging lowwall area, called Area 4.1, an inclined weak bedding plane, G1, will be daylighted along the lowwall as following by mine plans. The dimensions of Area 4.1 are nearly 300 m wide and 90 m high. The friction and dip angles of the G1 interface are reportedly 12° and 15°, respectively. A three million m3 claystone block, resting above G1, would potentially slide down, and possibly cause a massive failure. EGAT engineers are acutely aware of the potential gigantic sliding failure and are modifying the mine plan in Area 4.1 to improve mine safety and minimize the displacement of the potential sliding block, reduce the possibility of failure and lower the additional mining cost as much as possible. The cut and fill mining technique was selected and studied to achieve those goals for mining in Area 4.1. With this mining technique, G1 will be partially daylighted. Therefore, an arch formation is induced with a sliding block above the mining area, which could perform as a temporary support undercutting a certain span. Initial studies of the behavior of the partially undercut slope are presented in this paper, along with a review of the similar failure history in Mae Moh mine and a 3-dimensional numerical model of the mine. The failure history review provides an estimation of undercut span without failure. The three-dimensional numerical model results, using 3DEC, gave an initial approximation of the displacement of the sliding block in Area 4.1. The next exciting study of the behavior of partially undercut slope is a trial undercut slope field experiment in Area 4.1. Currently, a trial undercut slope field experiment in Area 4.1 is under construction. In the field experiment, a number of monitoring programs will be installed in Area 4.1 to monitor and obtain information to allow a better understanding of the behavior.

Jun 1, 2012

By R. Liu

As Building Information Modeling (BIM) becomes widely adopted by the construction industry, it holds undeveloped possibilities for supporting Facility Management (FM). Some FM information systems on the market claim to address the needs for FM requirement. However, the question of whether the functionalities provided by the current BIM-based FM software companies are those actually required by the FM Professionals still need to be answered. The data is required by FM professionals in the operation and maintenance phases of facilities and type of maintainability problems that frequently occur, which can be solved early in design phase, have not yet been addressed. The aim of this paper is to clarify the frequently occurring maintainability problems and to investigate the potential areas that can use BIM technology to solve the maintenance problems in early the design phase. A survey was conducted to collect perspectives from the industry practitioners for the maintenance problems and their frequency. The survey results indicated that maintainability considerations should be taken into consideration during the facility design phase. The results also address the perceived areas by practitioners that need maintainability consideration in design phase

Aug 1, 2013

By R. B. STEWART

A few days ago, while reading a report of the late Dr. Robert Bell in preparation for this afternoon's meeting, I found some impressive figures concerning the magnitude of the Hudson Bay basin. From the waters of the Bay itself, this great territory extends eastward 500 miles, westward l,300 miles to the Rocky mountains, and southward to the source of the Red river. It has a width of 2,100 miles from east to west, and a length of l,500 miles from north to south. Its area is almost three million square miles. It is not, of course, my intention to review the natural resources of this vast territory, but to confine my remarks to that portion of it adjacent to the waters of Hudson bay. A number of erroneous ideas exist in the minds of many concerning this northern country, especially as regards its latitude and climate. Burwell, at the entrance of Hudson strait, is in the latitude of 60 degrees or roughly that of the north of Scotland. The southern end of James bay has about the same latitude as the northern end of Vancouver .island.

Jan 1, 1928

By Frank S. Palkovits

Over the past 30 years, underground paste backfill systems have been implemented across the globe in many configurations, each with a primary focus of providing high quality backfill to enhance mine operations. However, a number of key design drivers are not always well understood within design engineering firms that occasionally undertake this work, leaving opportunities on the table. Perhaps not always obvious to those newly embracing paste technology, identifying key drivers and opportunities attainable through a paste backfill system is generally not straightforward, requiring innovative approaches to securing higher productivity, availability, performance, maintainability, and operator health and safety. This paper describes a number of applications and audits of paste backfill systems for several challenging mine operations. Key challenges include iterative design aspects of availability of good backfill materials, plant location and configuration, general arrangement, and binder receiving/storage systems.

Oct 1, 2010

By Ken McIntyre, Trodel Wolf-Dieter

"Sirius Minerals is a UK based fertilizer development company focused on advancing into operation its polyhalite project in North Yorkshire, England. The operation is known as the Woodsmith Mine which has an estimated 2.7 Billion Tonnes of reserves and is currently in the construction phase. DMC Mining Services was selected to carry out the construction of four shafts for the project, a production shaft of 6.75m diameter to a depth of 1594 m, a ventilation shaft of 6.75 m diameter to a depth of 1565 m, and two additional shafts to support the construction of the material transport system (the MTS and Lockwood Beck intermediate) to 360m in depth for servicing the underground conveyor network for transport of product from the mine site to the costal port facilities located at Teasside. This paper will review the status of the project to date and the innovative approaches that DMC is utilizing to ensure a safe and successful shaft sinking project. INTRODUCTION The Woodsmith Mine in North Yorkshire is a Sirius Minerals-owned deep potash and polyhalite mine located near to the hamlet of Sneatonthorpe, Whitby in North Yorkshire, England, approximately 75 km east of York. The area of interest is more than 700 km2. The £3.2 billion project is to develop the Woodsmith Mine to extract polyhalite, and a tunnel system to transport it to a materials handling facility and harbour at Teesside. The site is the world's largest and highest-grade deposit of polyhalite and is expected to produce 20 million tonnes of polyhalite, potash and POLY4 per annum, as well as create over 1,000 direct jobs and many more indirectly. It has the potential to generate over £2 billion of annual exports for the UK. As the project will require mining to be undertaken in the North York Moors National Park, many objections were raised about the mine. Sirius Minerals has gone to great lengths to ensure that the project is sensitive to the local landscape, including: mineshaft head frames that will be positioned below ground to reduce their visual impact; surface buildings will be kept to a minimum; and the entire site will be landscaped and screened by existing woodland to blend in with the surrounding area. The project will also abide by strict environmental limits which govern our activity during the construction phase."

Jan 1, 2019

By Himmelman. Nicholas P.

In this paper, the hardware foundations and data collection methods of a real time collision avoidance system for electric surface mining rope shovels are described. The primary goal of the system is to help a shovel operator avoid accidentally colliding the shovel?s dipper with either a nearby haul truck or the shovel?s tracks. To achieve this goal, the system requires complete and precise knowledge of the shovel?s geometry and movement, as well as the location of any nearby haul trucks. This paper describes the subsystems created to acquire this necessary information. This system is unique in that all of its components are mounted solely on the shovel and that it is designed to be easily retrofitted to a shovel without significant modifications.

Oct 1, 2009

By Meimei Zhang

In the overall open pit mine planning process, mining phase design is a strategic driver in guiding and constructing the block extraction sequence and determining the annual net cash flow distribution. Mining phase design should obey some practical constraints, such as ?minimum mining width? and ?flat mining phase bottom?, to allow space for haul road development and truck and shovel access on each bench. However, these practical mining phase design requirements are not taken into account in all first-cut mining phase design methods and post-processing is always required to convert an impractical design to a practical one, resulting in a potentially significant loss of Net Present Value (NPV) relative to the first-cut impractical designs. In this paper, we present a method using a meta-heuristic algorithm ? Simulated Annealing ? to enforce those practical constraints in determining a mineable phase design whilst ensuring minimum NPV loss.

Oct 1, 2009

By Zdenek D. Hora

British Columbia is an important producer of a variety of industrial minerals for both domestic and export markets. Some commodities such as limestone, dolomite, gypsum, calcium carbonate, silica, barite and magnetite are raw materials for well-established industries located in British Columbia, Alberta and northwestern USA. Others, like magnesite, sulphur, jade, asbestos, dimension stone and clay products, are mainly exported in processed form to overseas customers. Companies are developing markets for relatively new mineral products, including pumice, volcanic cinder and zeolites. A number of attractive geological targets have been identified by industry while research by government geologists has outlined the potential for refractory minerals, gemstones, garnet, nepheline syenite, carbonatites, residual kaolin, igneous apatite and peat.

Jan 1, 2001

By Karl J. C. Harries

"2.1. INTRODUCTIONNo agreement can be perfect in the sense that it contemplates and provides for all eventualities. Mineral acquisition agreements are usually negotiated and drafted at a time when an orebody is no more than a gleam in a geologist’s eye, so it is hardly possible to provide for development and operation in other than the most general terms. However, an agreement that stops short of contemplating the possibility of an orebody and production is ill-advised. Accordingly, it is important to provide procedures to make decisions that will let the project proceed, even in the face of a fallingout between parties. Whether the parties are shareholders in a corporation or venturers in a contractual common undertaking like a joint venture, differences of opinion and disputes will occur. Unfortunately, more and more are ending up before the courts. Besides greed and the growing tendency in society to fight rather than talk, there are other factors that contribute to the increase of litigation. In some jurisdictions, agreements have tended to become complicated, often defying interpretation, even by a lawyer, and explorationists want their budgets to go into the ground as constructive work rather than into a lawyer’s pocket. All this has led to a growing tendency for corporations to take the attitude that the chances of finding a mine are, at best, marginal and there are lots of earlier agreements in the files to draw from, so why not prepare their own agreements? As discussed in the preceding chapter, this can be folly. All these factors can quickly have parties facing each other in court while a project sits idle. Added to this is the problem that, in some jurisdictions, lawyers may take cases on a contingency-fee basis, sometimes promoting the pursuit of a nebulous claim.When an orebody is discovered, someone will always want some, or more, for himself. There is a breed of “prospectors” who prospect for legal actions, on the somewhat sound grounds that a major corporation will buy off nuisance litigation, rather than incurring the cost and effort of attacking even a poorly founded claim in the courts. They may even find a winner. Besides, it is far more comfortable and relaxing to prospect for problems and legal niceties than to prospect for an orebody.1 In short, it is appropriate to consider briefly some of the factors relating to lawsuits and judgments. Although many of the comments are made in the context of the common law and the Canadian legal system, most of the concepts and suggestions are applicable to any legal system."

Jan 1, 2003

"Option pricing is used in finance for valuing options to buy (or sell) shares at some future date because it provides a convenient framework for quantifying values subject to uncertainty. As one of the main sources of uncertainty in mining is the price (sales) of the metal, this approach can also be used for valuing mining projects.The first part of this paper reviews options and option pricing; the second part presents the approach developed by Brennan and Schwartz (1985) for using option pricing to value natural resources. Several applications of this methodology have been published; these are described. From a mining point of view, the assumptions made by Brennan and Schwartz are too simplistic. The weaknesses are discussed with a view to improving an apparently promising new way of assessing the value of projects. IntroductionThe collapse of the British merchant banking group, Barings, has highlighted the risks that can be incurred by speculators and arbitragers in the futures and options markets. But this negative attention on futures and options should not make us forget their positive aspects. They can provide producers and consumers of metals with more predictable sales prices. The introduction of the new traded average price options, TAPOS, by the London Metal Exchange in January 1997 is a response to this need. Equally important, the theory that the finance industry has developed for valuing options provides an interesting framework for valuing mineral projects as well. While this paper was being revised, the South African gold mining house, JCI, announced that it was using a methodology based on option pricing for valuing the mineral rights to deeplevel gold resources (see Box 1)."

Jan 1, 1997

By Atulya Verma, Samantha Espley, Nashel Kalaka

Numerical modelling simulations of proposed mining sequences are used to evaluate mining induced stress concentrations and their migration associated with the progress of mining. This analysis is a standard practice for most prospective mining projects at various levels of feasibility study. The studies are usually initiated at the beginning of the mining cycle, on a global scale, and are maintained and updated throughout the life of mine (LoM) to identify or address local issues and the required remedies as and when needed. Developments in numerical modeling techniques along with advancements in computing technology and data storage/management capacity have given rock engineers access to a huge volume of data that needs to be analyzed and assessed. The most common approach to numerically evaluate stress concentrations and migrations in underground mines is to select the points of interest in a given volume such as the back of an excavation or points within pillars around critical infrastructure, and plot the stresses or a derivative of stresses over time to represent life of mine concentrations and migrations of stresses. The problem with this approach is the sharp gradient of stresses close to excavation boundaries. Slight changes in the location of selected points can change the stress concentration and migration patterns substantially and all generalized statements about LoM risk can be challenged in one way or another. For global stresses, the most common current approach of data analysis is by viewing series of pictures representing stress contours. In this approach, it is easy to overlook some critical detail and/or be masked by personal preferences of contour/picture representation. To overcome the problem of representing and analyzing huge volume of stress simulation data, the authors, through their experience at different mining operations, developed a volume-based technique to reliably evaluate mining-induced stress concentrations and migrations. The volume-based approach is for risk-based assessments of adjacent regions in the rockmass, in and around planned stoping excavations. The volume of interest is the entire ore body that is planned to be mined, but it could be just a part of the ore body depending on the specific use case. The risk identifiers are the induced stresses as compared to the strength of the rockmass. Over the LoM, the risk identifiers are tracked versus the corresponding excavation ratio of the zone. This approach is very effective in identifying the stages of mining that are contributing the most to the mining induced stress risk and the results can be used for proactive planning and mitigations measures such as alternative mining sequences, or stope sizes, or extraction methods. The approach has also been very successful in application at mature mines, particularly in assessing the re-initiation of mining in zone that has been dormant for some time. The volume-based approach allows for an assessment of the current state of the rockmass and the identification of future risks when planning resumption of mining activities.

Jan 1, 2023

By S. K. Kawatra, S. J. Ripke, T. C. Eisele

It was determined by the authors that the water that remains in the filter cake after filtration in iron ore concentrators can contain several hundred times greater concentrations of calcium ions and other cations, due to surface chemical effects carrying the ions along with the water. Filter cake from two plants was analyzed. The water retained in samples of magnetite concentrate filter cake in Plant 1 contained 5088 ppm calcium and 5995 ppm magnesium, while the Plant 2 filter cake contained 231 ppm calcium and 119 ppm magnesium. These levels were dramatically elevated compared to the water that was removed from the concentrate by filtration for recycle to the plants (9 ppm calcium/15 ppm magnesium for Plant 1, and 11.9 ppm calcium/9.3 ppm magnesium in Plant 2). In addition to possible effects on agglomeration performance, the presence of these cations also affected the efficiency of filtration. In order to reduce the effects of these cations on filtration in Plant 2, carbon dioxide was injected into the slurry before it entered the filter press. This was found to increase filtration rates by up to 23.7%. Comparison of the results from the two plants shows that the concentrations of cations present in the filter cake will vary greatly from plant to plant, with correspondingly large variations in their effects on plant operations.

Jan 1, 2004

By Joseph Bradley

THROUGHOUT this article, minerals used in the paint industry are designated 'pigments'. They may be classified in two groups: (1) Pigments which are used in the state in which they occur in nature, requiring only mechanical preparation. (2) Pigments which require heating or chemical treatment before use, in order to obtain from them a product of the desired quality or shade of colour. They may be further classified according to colour, as follows: White Pigments .-These include calcium carbonate (chalk, marble), gypsum and alabaster, kaolin-or china-clay, and magnesia. However, the white pigments most extensively used are compounds prepared chemically from minerals containing lead, zinc, titanium, and antimony. The white pigments are of particular importance because, not only are they used by themselves, but they also serve as adjuncts to other colours for the production of special shades. Yellow Pigments.-These are mainly naturally occurring ferric hydroxides, as limonite and bog iron ore, or similar. compounds prepared artificially. Brown Pigments .-Pigments of this group are distinguished for their beauty and depth of colour, and many of them are used in the finest of paintings. Familiar names are sienna, umber, and Vandyke brown. They are for the most part ferric hydroxides, containing varying amounts of water; but the group also includes a manganese brown, which consists chiefly of a mixture of oxide and hydroxide of manganese. Red Pigments.-Chief among this group is ferric oxide, known under various trade-names, such as Canadian red, Persian red, etc., and also the much prized and somewhat rare vermilion. The pigment used is either naturally occurring hematite, de-hydrated limonite, or artificially produced red ferric oxide.

Jan 1, 1937

By Michael S. Moats, Shijie Wang, Timothy Robinson

In 1987, John Schloen published a survey and analysis of copper electrorefining tank room data. Following this paper, a series of copper electrorefining surveys have been conducted and presented at each of the Copper-Cobre meetings over the past 20+ years (1991, 1995, 1999, 2003, 2007, 2010 and 2013). For each of these surveys, William Davenport has been key driving force in the collection and analysis of data. To honour Professor Davenport’s contribution to copper processing, a review of the data was conducted. Historic trends and possible future technologies are discussed.

Jan 1, 2014

By O. W. Ellis

Introduction During the month of September, 1928 enough money had. been promised by private individuals and corporations to comply with the Research ?Foundation Act 1928 (Chapter 57, 18 George V) of the Province of Ontario. The Ontario Research Foundation (referred to below as O.R.F.) may be said to 1iave come into being at that time. Under the terms of this Act, the Treasurer of the Province was empowered to match dollar for dollar of the sums subscribed by private .corporations and individuals up to a limit of $1,000,000. However, the response to the appeal for this by the Premier of the Province, the Honourable Mr. G. Howard Ferg uson, was so exceptional that the Act was amended in 1929 so as to empower the Treasurer to increase the maximum contribution on the part of the Province to $2,500,000. In March, 1933, the Chairman of the Foundation, Sir Joseph Flaville, Bart., was able to report that, in the interval between the Premier's appeal and December 1st, 1932, private enterprise had paid ?into the treasury of the Foundation $1,670,050, and that the Provincial Treasurer had assumed responsibility for a like sum. The endownment Fund of the Foundation was, therefore. $3,340,100. This sum was ?invested a lm~ s t entirely in Government securities, in securities guar. anteed by the Government, and in 1mmicipal securities. Sir Joseph Flavelle remarked at that time that "The payment of $1,670,050 to the Endowment of the Foundation by private persons and corporations is a somewhat remarkable performance when it is remembered that for three of the five years the business of the country has been suffering from a severe depression". Since that time it has been the consistent policy of O.R.F. to live within the income derived (1) from the investment of its Endowment Fund and (2) from fees collected for services rendered.

Jan 1, 1950

By L. E. Young

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

Jan 1, 1989

By Cristina Echavarría

MAIN POINTS ? The region: opportunities and limitations ? Overview of main issues emerging from MMSD in South America ? Who comprises the local community? ? What are the main challenges? ? Some suggestions for companies to improve their contribution to local sustainable development of mineral rich localities THE REGIONAL CONTEXT 1. The region is a producer of minerals contributing over 20% to world metal production. It consumes only 8% 2. Significant diversity of national contexts-both between countries and within countries 3. Variable but predominant need for strengthening of government and community institutions and governance, especially at the local level 4. Dearth of baseline information for decision making 5. Sustained social spending during early 90?s as a consequence of economic recovery and fiscal policy, produced important advances in education and health 6. Despite government efforts in most countries poverty continues growing 7. Highly inequitable distribution of wealth persists

May 1, 2002

By Larry J. Hulbert, Louis J. Cabri, John L. Campbell, Gilles Laflamme, Chris G. Ryan, Soey H. Sie, Rolando Lastra

"Abstract- The mineralogy of samples from the Wellgreen Cu-Ni-Pt-Pd deposit, Yukon Territory, is complex and the metals of interest are contained within fme-grained minerais which vary in size and mineral associations from sample to sample.The major Ni carriers are pentlandite and violarite; the major Cu carrier is chalcopyrite. About 700Jo of the major Ni carriers and 78% of the major Cu qmier will be liberated at a grind of 80% -'}f,.7 J.Uil (-500 mesh) for typical low-grade gabbro (West zone, sample No. 1). For typical ""clinopyroxenite"" (West zone, sample No. 2) and typical ""clinopyroxene-rich peridotite"" (East zone, sample No. 3) the liberation would be 71""lo and 65% for Ni, 74% and 60% for Cu, respectively. Fine grinding, however, cannot liberate the Ni contained in silicates and pyrrhotite, estimated to total24.5% for typicallow-grade gabbro (West zone, sample No. 1), 15% for typical ""clinopyroxenite"" (West zone, sample No. 2), and 12% for typical ""clinopyroxene-rich peridotite"" (East zone, sample No. 3).The principal Pt carrier (sperrylite) varies considerably in grain-size between samples and fme grinding, required to liberate the major Ni and Cu carriers, may be counterproductive in samples where sperrylite is relatively coarse-grained, as sorne would then be unrecovered (e.g. sample No. 1). In addition, sperrylite in samples No. 2 and No. 3 is closely associated with magnetite.Palladium occurs in diverse ways. It occurs in the form of several Pd minerais (e.g. sudburyite, testibiopalladite, merenskyite), as a replacement for Ni in several tellurides, antimonides and tel­ lurantimonides (e.g. melonite), or as very low concentrations in pentlandite (up to 34 ppm), chal­ copyrite (up to 9 ppm), and pyrrhotite (up to 5.6 ppm). Palladium minerais and Pd-bearing minerals are strongly associated with chalcopyrite in sample No. 1 and will thus report to a Cu concentrate. However, 22% of the total Pd is in solid solution in pentlandite in this sample and will thus report to the Ni concentrate. In samples No. 2 and No. 3, less Pd occurs in solid solution in pentlandite, and the PGM are distributed mainly among pentlandite, chalcopyrite, and magnetite in sample No. 2, and among pentlandite, pyrrhotite, chalcopyrite, and magnetite in sample No. 3. Therefore, the feasibility of magnetic concentration should be investigated for samples like No. 2 and No. 3, in order to improve Pt and Pd recoveries.Rhodium was found to occur as rare hollingworthite, in sparse cobaltite (up to 2.7%) and, as low concentrations in chalcopyrite (to 10 ppm) and pentlandite (to 12 ppm) by proton microprobe. Iridium occurs in hollingworthite (up to 7.8%) and very rarely as the native metal or in an undefmed Re-Ir-Os-Ru alloy. Ruthenium was determined by proton microprobe analyses to occur in pentlandite (up to 13 ppm) and chalcopyrite (up to 10 ppm), in addition to rare laurite and Re alloy."

Jan 1, 1993

By M. R. KEYS

"The property is about 120 miles north of Red Lake in the Favourable Lake area, district of Kenora ( Patricia part) , Ontario. The original discovery was staked by K. Murray in December, 1927. The first development work was done by the Favourable Lake Mining and Exploration Company. In 1936 Newmont Mining Corporation acquired control of the property and developed it to production by September, 1939. Production to the end of 1945 had a value of $7,534,656 from 441,457 tons of ore, an average value of $17.04 a ton . This production was mainly from gold and silver, with lead and zinc of subordinate importance.The rocks in the vicinity of the mine trend in a north-south direction. From east to west the sequence is: (1) A dark-coloured, massive rock, presumably a flow, composed mainly of quartz and biotite. ( 2) A buff- coloured, scricitized rock locally containing quartz phenocrysts and black hornblende. This is an alteration product of the dark variety and is later than the folding. It occurs mainly within the dark rock. (3) A series of sediments comprising thin beds of greywacke, grit, quartzite, conglomerate, and iron formation. ( 4) A gabbro sill, now largely altered to amphibolite.With the exception of the buff type, these rocks dip 80°E. The buff rock has a very irregular outline in comparison with the other rocks and appears to dip somewhat more flatly east. Felsite and diorite dykes are also present. These have a general strike of S.60°E. and dip 65°S .W. A post-ore diorite dyke trending N.15°E. occurs about 2,000 feet east of the mine area."

Jan 1, 1954