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The reliability of mining systems is generally low due to their harsh working conditions. Currently, efforts for improving mining system reliability are often made in isolation. This practice could substantially limit the effectiveness of the efforts on overall reliability improvement of the mining system. To enhance the overall reliability of mining systems, an integrated improvement approach is necessary. In this paper, we developed a framework for integrated mining system reliability improvement to address this issue. In this framework, there are five major components including data integration, business process integration, hardware integration, software integration, and analysis/decision integration, but we only focus on the integrated reliability analysis which is important to the analysis/decision integration. The reliability analysis considers the interactions between machines, and the impacts of design, operation, maintenance, automation and working environment on the overall system reliability. These multiple interactions present a big challenge to accurate reliability prediction. In this paper, we for the first time systematically investigated integrated reliability analysis approaches for dealing with this challenge using novel models and methods, including covariate hazard models, intelligent reliability prediction approach, and complex system modeling methods. While these models and methods have found some successful applications in other industries, they in general have not been effectively used for the reliability analysis of mining systems. Our study results show that the system integration approach is applicable to mining systems and can be used for developing a computer aided integration system for the implementation of the integrated reliability improvement approach.

Aug 1, 2013

By Akira Miura, Katsuyuki Sato, Yuken Fukano

JX Nippon Mining and Metals Corporation has developed the JX Iodine Process, which is an innovative and patented copper-leaching process for low-grade primary sulfide ores. This process consists of the irrigation of ferric iron and a low concentration of iodide solutions. One-meter column leaching tests were conducted on ore samples from two different mines. At the end of experiments, the total copper recovery exceeded 70% for Sample A and 50% for Sample B with the iodine method, which was significantly higher than that with conventional ferric leaching of 14% for Sample A and 20% for Sample B. To elucidate the reason for the JX Iodine Process effectiveness, cross sections of leached residues were studied. Reaction products were confirmed around chalcopyrite even in the central area of particles in Sample A, however, reaction products were recognized at a depth of only 1 mm from the ore rim in Sample The resistance of Sample A to the leachate appeared to be lower than that of Sample B because Sample A had a high permeability and porosity, whereas Sample B had been affected strongly by a potassium alteration. No reaction products were visible on conventional leaching samples, even at the ore surfaces. INTRODUCTION Hydrometallurgical copper leaching (heap leaching or dump leaching) has been used extensively for copper recovery from oxide and secondary-sulfide ores, but not for primary copper sulfides, which contain mainly chalcopyrite as copper minerals. Although they are major resources of copper, primary copper sulfides are difficult to process because of their refractory nature. Extensive leaching studies have been carried out to leach primary copper sulfides (chalcopyrite), including biological and chemical, using a variety of oxidants and additives to enhance copper recovery. Watling (2013) reviewed acid-chloride-oxidizing agents with chalcopyrite. Abdollahi et al. (2015) tested silver as a catalyst for bioleaching with a chalcopyrite-bearing molybdenite concentrate. Hiroyoshi, Miki, Hirajima and Tsunekawa (2000) found a specific redox-potential zone for high-speed chalcopyrite leaching by controlling the ratio of ferric and ferrous iron. However, no ambient-temperature economic process has been developed for leaching primary copper sulfide, which usually has a low copper grade.

Jan 1, 2019

By Sammy Bansah, Komla Dzigbodi-Adjimah

Abstract-Ghana, a major West African gold-producing country, took a crucial step in 1986 to allow private participation in mining ventures that had hitherto been state controlled and starved of funds. This decision has led to a three-fold rise in gold production with substantial local and foreign capital once again flowing into exploration and mining projects. Though the rise in gold export is due primarily to increased production from large mines such as Ashanti Goldfields Corporation, Billiton Bogosu Gold, Tebrebie Goldfields and Ghana Australia Gold that work primary lode gold deposits on quartz veins and Banket conglomerates, a fair amount of gold comes from placer gold mining from which two new mines have been developed at Kwabeng and Bonte during the current gold boom. Also, placer gold mining is important locally because the lower capital outlay required for its development enables many entrepreneurs to operate small concessions and provide employment for a large pool of unskilled labor. Placer gold exploration and development in Ghana is labor-intensive. Pitting is the most used method although few employ the mechanized ("Banka") drilling. The advantages and disadvantages of the two approaches in the local setting are discussed. The gravel is normally sluiced and the gold recovered by amalgamation. The drawbacks to successful placer gold exploration in Ghana have been attributed to lapses in execution of exploration programs (Dzigbodi- Adjimah and Arhin, 1993; Dzigbodi-Adjimah and Gawu, 1994). However, the failure to recognize and set time frameworks and financial limitations for the various stages of placer gold exploration have spelt the doom of some projects. It is critical that the characteristics of the placer gold deposit be determined by efficient and cost effective means. A planned exploration supported by adequate flow of funds saves costs and leads to success. This article discusses the current Ghanaian situation and presents proposals from case studies for planning and budgeting placer gold exploration programs for use in similar settings.

Jan 1, 1995

By Sammy Bansah, Komla Dzigbodi-Adjimah

Ghana, a major West African gold-producing country, took a crucial step in 1986 to allow private participation in mining ventures that had hitherto been state controlled and starved of funds. This decision has led to a three-fold rise in gold production with substantial local and foreign capital once again flowing into exploration and mining projects. Though the rise in gold export is due primarily to increased production from large mines such as Ashanti Goldfields Corporation, Billiton Bogosu Gold, Tebrebie Goldfields and Ghana Australia Gold that work primary lode gold deposits on quartz veins and Banket conglomerates, a fair amount of gold comes from placer gold mining from which two new mines have been developed at Kwabeng and Bonte during the current gold boom. Also, placer gold mining is important locally because the lower capital outlay required for its development enables many entrepreneurs to operate small concessions and provide employment for a large pool of unskilled labor. Placer gold exploration and development in Ghana is labor-intensive. Pitting is the most used method although few employ the mechanized (“Banka”) drilling. The advantages and disadvantages of the two approaches in the local setting are discussed. The gravel is normally sluiced and the gold recovered by amalgamation. The drawbacks to successful placer gold exploration in Ghana have been attributed to lapses in execution of exploration programs (Dzigbodi-Adjimah and Arhin, 1993; Dzigbodi-Adjimah and Gawu, 1994). However, the failure to recognize and set time frameworks and financial limitations for the various stages of placer gold exploration have spelt the doom of some projects. It is critical that the characteristics of the placer gold deposit be determined by efficient and cost effective means. A planned exploration supported by adequate flow of funds saves costs and leads to success. This article discusses the current Ghanaian situation and presents proposals from case studies for planning and budgeting placer gold exploration pro-grams for use in similar settings.

Jan 1, 1995

By Jose A. Jimenez

"Mining operations generate an enormous amount of data that is difficult to organize, analyze and act on. These data require an extremely broad range of experts to investigate and manage the cross-disciplinary information. The data collects in paper files, diverse databases, historians, stand-alone applications, and excel files. This collection of sources represents everything from monthly, weekly, or daily inputs to real-time feeds or sporadic unscheduled entries. With the operational complexities ever increasing and fewer engineers per mine, an efficient operation is becoming more and more challenging. Engineers are typically burdened with data collection, clean up, and administrative efforts leaving very limited time for engineering assessment and/or optimization analysis. Often optimization becomes limited to the analysis of equipment uptime through existing field automation systems. A great portion of the field data is tucked away in historians seldom reaching those engineers who might leverage the data. Few mine operators have the time or budget to re-architect their operations data collection or management practice, so solutions must enable improvements without requiring expensive or time-consuming implementation. This presentation highlights examples where the aforementioned challenges are addressed using a solution framework designed to enable: 1) data integration and connectivity, 2) monitoring and opportunity recognition, and 3) engineering workflow automation. The initiative extends the concepts and success proven in the automation market segment to all disciplines across the mine operations. INTRODUCTIONThe mining industry by its very nature spends a great deal of its capital on equipment maintenance and replacement. In addition, periodic shutdowns due to equipment failure are typically very costly in terms of interrupted operations. Keeping mining equipment running at peak performance and avoiding costly shutdowns can make a huge difference in the overall return from mining operations. Today, information can be make available that can go a long way towards spotting equipment issues and permitting timely intervention to avoid costly unplanned shutdowns. That said, gathering all of the information from numerous points on many different pieces of equipment necessary to enhance overall equipment effectiveness presents its own daunting issues."

Jan 1, 2016

By A Smirnov

The problem of thin and very thin coal seam extraction is examined in a long perspective of Ukraine?s fuel and energy industry development. The technical and economic benefits of the coal seam selective mining technique are described, including beneficial environmental impact.

Aug 1, 2013

By I. Orford, V. Rozon

"The Sä Dena Hes Joint Venture Mill was designed to process 450,000 tonnes per year of ore grading 11.3% lead and 13.2% zinc.Run of mine ore is crushed in a jaw crusher and then ground in a closed circuit SAG mill and ball mill. A standard differential float in conventional flotation cells produces quality lead and zinc concentrates. Dewatering of concentrates is achieved using high rate thickeners, lamella clarifiers and pressure filters. Process water is 100% recycle.Plant design was based on metallurgical test work performed on drill core samples. The plant is operating at better than design specifications.INTRODUCTIONSä Dena Hes Joint Venture was formed in 1989 to develop the Sa Dena Hes lead/zinc sulphide mine, located approximately 45 km north of the Town of Watson Lake, Yukon. The mine is owned by a Joint Venture partnership between the operator, Curragh Inc. (87.5%) and Hillsborough Resources Limited (12.5%).The project was completed in a record ten months, working throughout the severe Yukon winter and through an abnormally wet spring and summer. The first truckloads of concentrate were shipped from the mine on August 1, 1991.The mill currently processes 550,000 tonnes of ore per year grading 6.9% lead and 11.5% zinc. Ore is crushed in a jaw crusher and ground to 60% passing 75 microns in a closed circuit operation of one SAG mill and ball mill. Using conventional flotation cells a 150,000 tonnes of concentrate is produced in a year with lead concentrate grading 78% lead and a zinc concentrate grading 60% zinc at overall recoveries of 89% and 90% respectively.Concentrates dewatering is accomplished using high rate thickeners, clarifiers and pressure filters. The lead concentrate and zinc concentrate contain 5.4% water and 7.8% water respectively. Concentrates are trucked to Skagway, Alaska for subsequent shipping to overseas smelters."

Jan 1, 1993

By A. Gakwaya, P. Vachon-Joannette, P. Gagnon, J. Lévesque

"Predictive numerical methods are essential tools for reduced development cost and improved high performance designs of modern aircrafts. Their use leads to savings in terms of design cycle time and experimental trials. Composite materials subjected to impact loadings demonstrate various damage modes such as matrix cracking, fiber breakage, delamination and, ultimately, fabric fracture. Composite laminates are extensively used in the aerospace industry, and their damage modeling is complex due to their inhomogeneity and anisotropic behavior. Damage evolution affects both in-service properties and performance of these composites. In this work, the drop-weight impact test has been simulated. Using a material model that accounts for both delamination and intralaminar damage, laminates response is analysed using numerical simulations based on 3-D finite-element models of the commercial code Abaqus/Explicit. Experimental and simulation results are compared, in terms of energy absorption and contact force. The obtained numerical results show good agreement with experimental data.INTRODUCTIONAs primary aircraft structures are increasingly being made from advanced fiber-reinforced polymer matrix composites and are in general exposed to a variety of impact scenarios (bird, hail, debris etc.), an understanding of the impact event and the performance of composite materials during impact is important in the development of new structures. This work is focussed on low velocity impacts that typically occur when foreign objects hit the aircraft during maintenance or other on-the-ground operations. These impacts can cause non visible damage that affect the structural integrity of the composite components. While for metallic structures, damaging impact events typically leave noticeable dents due to plastic deformation, in contrast, for high strength carbon fiber reinforced composites, they can deform elastically to strain levels exceeding 1% and the internal damage can often occur without the formation of a visible dent. The identification and effect of impact damage on the performance of the structure is thus of great concern to the aircraft industry as the durability and damage tolerance of these composite structures are strongly influenced by the size of detectable internal damage."

Jan 1, 2016

By R. T. Erskine

"IntroductionIn this paper it will not be possible to cover all details of the reagent systems at Brunswick Mining and Smelting but it is hoped that a description of the evolution of these systems will be of some benefit. The concentrator of Brunswick Mining and Smelting located near Bathurst, New Brunswick was originally designed as a 3,000 ton per day operation but before construction commenced was uprated, with 4,500 tons per day being treated by the summer of 1964. Development of the open pit at another ore body five miles away was initiated in 1965 and additional concentrator and crusher facilities went into operation in September, 1966. Present total daily throughput is over 8,000 tons per day. The ore at Brunswick is very high grade but mineralization is very fine grained and requires grinds generally over 75% minus 400 mesh for liberation. The amount of surface exposed using grinds of this order understandably requires great quantities of reagents, Reagent mixing systems for the original concentrator allowed only for batch mixing and were very expensive in labour cost especially.During the first three years of operation total number of men employed in reagent handling reached a peak of four men per shift and six men on dayshift unloading cars for a total of 22 men. At present only one man is employed on shift, and four men on dayshift take care of unloading and mixing reagents, a total of 8 men. The man on shift is almost entirely occupied with checking feeder operation, flow rates, and head tank levels. Most commonly used reagents are tabulated in Fig. 1 showing average monthly and daily requirements in the Brunswick operation as well as pounds per ton of mill feed as found in 1969. It is very obvious that with over seventeen tons each of lime and soda ash and six tons of copper sulphate used each day, opening of bags and mixing batches of solution is an inefficient undertaking."

Jan 1, 1970

By V. Vekris

A diverse patent portfolio and an effective intellectual property strategy are vital in today’s small business world. Not only does a diverse patent portfolio enable a company to secure a monopoly within the market, it greatly increases the value of a company’s intangible assets and keeps competitors at bay. An overview of the patenting process as it pertains specifically to the materials science-related start-ups will be given, together with a summary of some general patenting strategies and a review of some patenting errors to be avoided, such as premature disclosure of the invention to the public. Additionally, a review of new “green technology” initiatives recently adopted by Patent Offices around the world is also provided. These initiatives are expected to greatly benefit patent applicants in the fields of metallurgy and mining, where research efforts are often directed to environmentally-friendly products and processes. INTRODUCTION Patents are playing an increasingly significant role in the business world. A diverse patent portfolio can enable a company to secure a monopoly within the market, which can provide a competitive advantage over competitors. At the same time, patent portfolio of any size can greatly contribute to the total value of a company’s intangible assets. As an example, Nortel entertained bids in 2011 for its portfolio of about 4000 patents, a large portion of which were directed to 3G- and 4G-mobile communication technologies. The portfolio was eventually sold for $4.5 billion to a consortium including Apple, EMC, Ericsson, Microsoft, Research in Motion, and Sony. Copper mining, and indeed the global mining industry as a whole, is facing challenges. Ore deposits are increasingly low grade, complex, and deeper in the ground, rendering copper mining operations more difficult and costly. Production costs are increasing. According to one study, the cost of producing copper has increased by an average of 10% per year since 2005 (Cantallopts, 2017). To illustrate, the cost of producing a pound of copper in 2005 was 90 cents, but had increased to 217 cents by 2014.

Jan 1, 2019

By A. A. Bakke

"The Fort Knox gold deposit is hosted within the Fort Knox Pluton, a Cretaceous multiphase granitic body that intrudes the Fairbanks schist. Gold occurs along the margins of stockwork veins and veinlets, quartz-filled shear zones, and along fractures within the granite. The mineralization is generally sulphide-poor and closely associated with trace amounts of bismuth, tellurium and to a lesser extent with molybdenum and tungsten. At present, proven/probable reserve estimates, based on a cutoff grade of 0.39 g/t Au, are 158.3 million tonnes grading 0.83 g/t Au.The Fairbanks schist comprises the bulk of the country rock. The dominant lithologies present include muscovite-quartz schist and micaceous quartzite. Immediately north and south of the main orebody, mixed metamorphic lithologies of the Cleary sequence, a subunit of the Fairbanks schist, have been mapped. Development of local zones of weakness, most likely due to a broad regional warping event, resulted in brittle-ductile deformation and activation of a northwest-southeast shear couple between contrasting lithologies.The Fort Knox Pluton consists of at least three phases based primarily on textural differences. Intrusion of a fine-grained granite was followed by a medium-grained porphyritic granite. The youngest intrusive phase is a coarse-grained, seriate porphyritic granite, the Vogt Stock. The Vogt Stock forms an elongate dome with the axis in the east-west direction. Structures displayed in the overlying units, believed to be the result of doming, include tension fiSSUres and longitudinal fractures.Premineralization fractures, the result of the magmatic doming, provided conduits for initial stockwork quartz vein development and quartz enrichment in shear zones. Weak development of vein-controlled phyl/ic, potassic, albitic, and argillic alteration styles are present. Evidence of a late thermal event resulting in a low-temperature alteration assemblage of calcite + zeolite (stilbite) + chalcedony + clay occupies breccia zones, joint surfaces, and fractures within the granite."

Jan 1, 1995

By Jaeheon Lee

"Biooxidation of gold ores or concentrates could be a very attractive alternative to pressure oxidation (POX) or roasting to liberate the gold grains from various sulfides. Crushed heap bioleaching was successful in US and many operations using tank bioleaching of gold concentrate are currently running around the world. Many parameters need to be considered during the project of sulfidic refractory gold ore process. Capital and operation costs are among the most important ones. Run-of-mine heap biooxidation could be very inexpensive and the smaller the crush size (particle size), the more expensive the capital and operating costs for biooxidation application are expected. The capital cost of biooxidation could be a fraction of the cost for building POX plant or roaster and the operating cost could be 1/3 of POX or roasting depending on the method utilized. A new biooxidation process, Sand Farming, is introduced as an alternative to POX and tank biooxidation process. A relatively coarser particle size (P80 = 650 µm) of the process benefits the low cost of grinding against the conventional grinding size (P80 = 75 µm) for other options. The cost of Sand Farming is less than 40% of that of pressure oxidation with comparable gold recovery from the downstream process. This paper will review the laboratory scale testwork for various biooxidation process of sulfidic refractory gold ores and concentrates and provide the economic evaluation showing the biooxidation could be the most economic method without much sacrificing the overall gold recovery. INTRODUCTIONThe decreased availability and lower grade of raw materials has motivated industries to consider recovering values utilizing low cost process options. The process may treat high grade concentrates or submill grade ores that cannot be processed economically by conventional milling-flotation or leaching. Sulfidic refractory gold ores/concentrates have been economically processed by roasting, pressure oxidation, and biooxidation in stirred tank reactor. The process selection is based on a series of studies including multi-year long ore characterization and metallurgical investigations."

Jan 1, 2016

By J. A. MacLellan

"CONSTRUCI'ION OF SHERRITT'S CONCENTRATORSSherritt Gordon is operating two mills north of the 56th parallel, and is presently engaged in building a third. The author was closely involved in the design and construction of all three of these concentrators.The Lynn mill is the oldest of these three concentrators-it is a 4,000 ton per day nickel-copper plant built in 1953. The Fox mill is a 3,000 ton per day copper-zinc concentrator built in 1970. The Ruttan mill will be a 10,000 ton per day copper-zinc plant scheduled to go on line in July 1973.LYNN MILL The Lynn mill including the crushing, concentrating, drying and load out plant is about 69,700 square feet or 17.4 square feet per ton per day. '!his plant was originally built in 1927 at Sherridon, 150 miles south of Lynn Lake, as a 2,000 ton per day copper-zinc plant. In 1952 the plant was moved by tractor train to Lynn Lake. The whole plant was re-oriented within the original perimeter walls as a 2,000 ton per day nickel-copper plant. This plant was expanded to 4,000 tons per day by the addition of t1-Jo rod mills and a 5-1/2 short head crusher in 1959.The Sherridon mill processed its last ore in Sherridon in September 1951 and the first load of nickel concentrate was loaded at Lynn Lake on November 9, 1953 when the railroad arrived at Lynn Lake.The site for the Lynn Lake mill was cleared of overburden in the summer of 1952 and foundations for structural steel and SO!l8 equipment foundations were poured the late summer and fall of 1952 • Steel was erected from January to June 1953. Most of the equipment came in from January to March of 1953 by tractor sleighs. Sane sleighs upset but no equipment was lest through the ice."

Jan 1, 1972

By J. A. Haskin

The Engineering Department at Flin Flon has the following responsibilities: 1. Underground Surveying. 2. Open-Pit Surveying and Supervision of Blasting. 3. Mine Geology and Examination of Prospects. 4. Design of Plant Additions and Improvements. 5. Miscellaneous Field W ork, Reports, etc. The entire surface plant, as well as the underground workings, are located by co-ordinates based on a triangulation system covering an area approximately one mile long by one-half mile wide. The origin of this system and one end of the base-line is the southwest corner of Township 67, Range 29, west of the Principal Meridian. The bearing of the base-line was determined from the township boundary, which runs true north, so that all other bearings are almost astronomical. This is a great convenience when our surveys must be tied to mineral claims, rights-of-way, and land subdivisions. As the base-line extends across Flin Flon lake, its measurement across smooth ice was simple and accurate. The length, slightly over 1,600 feet, has been adjusted for the temperature and tension of the standard tapes used and checked sufficiently to ensure a maximum error of 1 : 15,000. Each angle was repeated ten times, but as no special refinements were used, errors of as much as four or five seconds are possible. The elevation of the origin of the triangulation system was approximately 1,050 feet above sea level. The use of this true elevation in our surveys would have resulted in negative elevations underground as soon as the mine reached a depth greater than 1,050 feet. To avoid this complication we therefore added 4,000 feet to this elevation. The collar of the Main shaft, for example, which is actually 1,072 feet above sea level, appears in our records as at elevation 5,072. Underground surveying, which follows standard practice, is done by two mine surveyors who share three helpers. The meridian is taken underground from two wires hung in either of the two vertical shafts.

Jan 1, 1935

By Nelson Lawrence

An Electrical Risk Management/Inspection Program has been designed specifically for the mining sector in order to provide electrical code expertise and systemic gaps in electrical systems. Goals include improved safety and productivity, reduced injuries and help to enable businesses to better comply with the electrical codes and regulations that govern them. The Electrical Risk Management/Inspection Program is now recognized by some of the world?s largest mining organizations. Since June, 2001 these electrical safety advisory services have been available to underground and surface mine sites throughout Ontario and are now offered throughout Canada and around the globe. This program is also currently being applied to review new electrical installations for mine construction projects thus improving the safety and reliability of mine site electrical systems.

May 1, 2006

By A. L. MacAllister

"Keymet Mine lies on the Elmtree River 4 miles west of Petit Rocher and about 18 miles northwest of Bathurst, Gloucester County, New Brunswick. A good gravel road runs through the property.The deposit was discovered in 1880 when a vein 7 to 8 feet wide was re-ported. In 1883 the first shaft was sunk as part of an exploration program which was carried out sporadically until 1897, when the company dissolved. Activity on the property was intermittent until 1946 when the property was again staked and during the next year diamond drilling intersected the vein in several places. In December 1949 Coulee Lead and Zinc Mining Company optioned the property and held it until its sale to Keymet Mines Limited in June 1952. By July of the same year work had begun on a three-compartment shaft.Early development work was concentrated on the 150, 300 and 450 foot levels but the shaft has since been sunk to I,228 feet to allow for eight levels at intervals of 150 feet. Little lateral work has been done to date below the 600-foot level.The first mill constructed to treat the ore was to go into production in the spring of 1954, but was destroyed by fire. A second mill, having a capacity of 200 to 300 tons a day, was officially opened October 25th, 1954. Present shipments are zinc and copper-lead-silver concentrates.The rocks of the area are shale, conglomerate, limestone, and quartzite with minor interbedded volcanic rocks, all probably of Silurian age. Small plugs of Devonian acidic intrusions occur 3 miles east and about 5 miles northwest of the mine. Minor dykes of both acidic and basic rocks occur on the mine property. In many of the fine-grained sedimentary rocks the more brittle laminre have been brecciated and give the rock the appearance of an argillaceous conglomerate."

Jan 1, 1949

By A. Bouajila

To stay competitive in an open market, mineral industries have to optimise their processes, lower their production costs and improve the commercial value of their products. Up to a recent past, they were impaired in this attempt by a lack of adequate devices allowing reliable on-line and real-time process monitoring (detection or measurement). Process monitoring for process control and the product characterisation for quality control are quite different tasks. Planners and researchers should be fully aware of this when evaluating or developing monitoring equipment for on-line process control. This paper will comment on some aspects of sensor specifications, during the design and the evaluation steps, related to sampling, measurement (accuracy, sensitivity, delay and correlation to the process) and suitability to the exploitation environment. Examples of R&D projects promoted by COREM for various industrial applications will be presented.

May 1, 2001

By George A. Guess

The making of contracts for the purchase of ores is a business which the metallurgist usually understands better than the miner. Companies in the custom ore business often employ an ore buyer who is aware of the class of ore which the smelter needs, and is thoroughly conversant with the business. The miner on the other hand makes ore contracts but seldom, and it is often only after a settlement has been made that he realizes the meaning of the terms of the contract under which he has sold his ores. He has expectations usually greatly in excess of the amount 'net proceeds' shown at the bottom of the settlement sheet. Seldom does the occasional shipper really know his contract. A somewhat similar parallel is to be found in insurance policies. We all have insurance policies; we never know the conditions contained in them until after the fire. The clauses in the policy are for the protection of the Insurance Company. An Insurance Company has no friends.

Jan 1, 1926

By W. E. Cockfield

THE object of this paper is to review recent geological work in the Cariboo district and to present notes on the recent development of mineral properties. The Geological Survey has done considerable work in the Cariboo district, extending over a period of years. In 1885 and 1886, Bowman (1) mapped the geology of a large area. In 1922 and 1923, Johnston and Uglow (2) mapped Barkerville area in some detail and prepared a report on the placer and lode gold deposits. In 1931 and 1932, Cockfield and Walker (3) mapped the Quesnel Forks area. In 1933, Hanson reported on Willow River area ( 4), and in 1934 made a detailed examination of part of the Barkerville area (5). In 1935, Lang commenced work on the Keithley area, lying to the southeast of the Barkerville area, and in 1936 published a preliminary re-port (6). The work on Keithley area was continued in 1936 by both authors of the present paper. As the results of the earlier work have been published, this paper will be concerned largely with Keithley area, that is, the part of the region lyinp between longitudes 121° 00' and 121° 30', and latitudes 52° 45' and 53° 00 . This area lies astride Cariboo (Swamp) river and extends north some 17 miles from Keithley, which is situated near the southern border of the map-area (see sketch-map). Points in the western part of the map-area are fairly accessible. A road extends from Barkerville to upper Cunningham creek, and from this a trail crosses Snowshoe plateau to Keithley. A second trail from this road leads to the lower falls on Cariboo river. From this road, a branch road leads to upper Antler creek, with a trail leading from this branch road to Keithley. Part of this western half of the area is made up of the Snowshoe plateau, which constitutes a gently rolling surface, at or above timber line, where trails are largely unnecessary.

Jan 1, 1937

By E. A. Collins

I TAKE it that the papers presented tonight on the subject of Reconstruction, as regards both gold and base-metals, are intended primarily to stimulate discussion of this important subject and, in regard to base-metals in particular, cannot in any manner be considered as a policy or plan to be followed as a panacea for all the ills which are bound to beset the industry when peace is declared. A famous cook-book written by a Mrs. Beeton contained a recipe for jugged hare which began with the instruction, "First catch your hare". To date, we have not caught the hare of victory and it may seem to many that any thought, energy, or effort devoted to the problem of reconstruction which will in any way impede the acceleration of the chase after victory will leave us open to the charge of being derelict in our duty as citizens. Much of our present trouble is due, however, to our lack of preparation for war in time of peace, and it follows that it is of equal importance in our national economy to prepare for peace in time of war. Most of us here tonight have vivid and sad memories of the chaos in the metal mining industry following the Great War of 1914-1918. In our own industry, mining, smelting and refining of nickel and copper, it was not a problem of absorbing the men who returned. There were only some three hundred who came back to the Mining and Smelting Division, and these men were all given their former jobs without any apparent difficulty. They were rehabilitated gradually due to the fact: that some of these men did not return for a year after the Armistice was signed. The numbers of men involved in the present conflict are much greater. We have to date in the armed forces upwards of 3,000 men enlisted from our employ.

Jan 1, 1943