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By A. A. Brant

ONE of the reasons advanced for the decline in prospecting and discovery is that, as regards surficial examination, the law of diminishing returns is becoming applicable. Fewer surficially unprospected fields remain; therefore, fewer discoveries by such means result. Much in the nature of mineral resources remains to be unearthed, but even now, and more so in the future, will discovery depend on painstaking petrographic and structural mapping, aided, where necessary, by judicious applications of all the complementary scientific knowledge and devices (e.g., thin section microscopy, geophysics, and drilling) that experience proves effective in localizing a mineral deposit even beneath drift, lake, or muskeg. It is to be expected, then, that the rate of discovery will decrease, that the cost per discovery will greatly increase, and that the work of discovery will become more and more the careful, methodical assembling of field data, conscientiously interpreted on the basis of scientific knowledge by trained, experienced operatives. In view of these trends, the status of applied geophysics to Canadian mining exploration and development work might well be reviewed. The niche which geophysics may occupy relative to geological surveying and drilling has been clarified by the last twenty years' experience. The cloud of somewhat justifiable scepticism that followed the 'geophysical promotion' period of the late 1920's has lifted. Mining, exploration, and finance companies, in open-minded fashion, are seeking sound advice as to what are the scope and limitations of the geophysical methods at present practised. The purpose of this paper and the following one is, therefore, as far as lies within the author's power, to review briefly the geophysical methods at present in practice in Canada, and, at greater length, to joint out impartially and critically their scope, merits, shortcomings, an possible future development. The treatment will be non-technical, the hope being that an accurate statement of the present status of geophysics in Canada may do much to result in a sounder, saner growth of what, in the future, shall undoubted} y prove an increasingly useful tool in exploration and development work. ?

Jan 1, 1942

By M. B. McClenaghan

"Abstract- The Ontario Geological Survey completed a regional till sampling project between 1984 and 1988 in the Black River Matheson (BRiM) area of northeastern Ontario. The project was designed to aid mineral exploration in the area by documenting the Quatemary stratigraphy and by providing a database of till geochemistry. This paper summarizes the results from the sonic overburden drilling component of the BRiM project carried out in areas of thick drift (> 5 m). Results from till sampling in areas of thinner drift (<5 m) have been presented in a separate paper. Approximately 1100 till samples were collected from 225 sonic drill holes. For each sample, the non-magnetic heavy mineral (> 3.3 S.G.) and fine (-250 mesh) till fractions were analyzed geochemically and visible gold grains were recovered by panning.Gold and other multielement geochemical data were plotted using proportional symbols to high­ light anomalous areas and to demonstrate how to evaluate and interpret a very large geochemical dataset. Thresholds for identifying anomalous concentrations of Au in till samples, defined using the 95th percentile, are 1500 ppb and 12 ppb for the heavy mineral and fine fractions, respectively. The heavy mineral fraction of older tills and to a lesser extent, Matheson Till, display a number of significant gold anomalies in the study area, which in a few cases, are associated with base metal anomalies. The vertical position of gold anomalies in Matheson and older tills varies from directly on bedrock to several meters above the bedrock surface and can provide information of relative ice transport distances."

Jan 1, 1994

By P. Curry, H. G. Stephenson, B. Van Den Bussche

"Three Sisters Resorts Inc. currently owns a2035 acre (824 ha) parcel of land, which previously belonged to Canmore Mines Ltd. Approximately 50% of these lands, that are slated for residential, resort and recreation development, have been undermined for coal in one or more seams.Norwest Mine Services has been contracted by the developer to assess and advise them on any past mining activity that may be potentially hazardous to their development and offer solutions to how these hazards may be mitigated or avoided.The following paper deals mainly with the procedures put in place and accepted by the approval authorities, and the Staged approach to the Investigative Procedure that Norwest follows in the mining assessment and mitigation work for Three Sisters."

Jan 1, 1996

By B. A. Kjarsgaard, C. J. Mwenifumbo

"Abstract - Natural gamma-ray measurements were made in the GSC Smeaton drillhole as part of the borehole geophysical classification of kimberlite pipe 169. In addition, forty samples of Cretaceous sediments (shales, siltstones, and sandstones) and thirty-five kimberlite samples, selected from the drill core, were analyzed for major and trace elements. These elements included potassium (K), uranium (U), and thorium (Th), which are the main naturally-occurring radioactive elements.Different phases of the kimberlite, and the Cretaceous sediments which show variations in the gamma-ray activity, can be easily delineated on the gamma-ray logs. The gamma-ray logs indicate that the radioactivity in the kimberlite derives mainly from Th, and, to a lesser extent, U. Most of the kimberlite units are enriched in Th and U relative to the Cretaceous sediments, and these radioelements are mainly hosted by accessory apatite and perovskite, and minor zircon. Potassium concentrations are low in the kimberlite. The higher K concentration in the sediments clearly distinguishes the Cretaceous sediments from the kimberlite.The U/K and Th/K ratios show important and distinct differences between the two major types of volcaniclastic kimberlite. Kimberlite lapillistones have higher U/K and Th/K ratios than the olivine crystal tuffs. Furthermore, standardized U/K and Th/K geophysical logs can be used to separate marine reworked olivine shoreface sands from other shallow marine sediments that contain kimberlitic detritus. The identification of different phases and/or stratigraphic facies of kimberlite on the basis of radioelement distributions means that gamma-ray spectrometry can assist exploration, particularly in regard to diamond grade distribution."

Jan 1, 1999

By P. Lind, A. Gagnon

"Goldcorp has embarked upon an ambitious, industry-leading, multi-year water use reduction effort. This is a proactive, voluntary effort that reflects our commitment to truly sustainable mining. This effort will focus on increasing water re-use and recycling, and reducing water inputs ultimately towards zero. All of our operating mines are expected to contribute to this effort and are currently in the process of developing plans to meet short and long term objectives. One of the largest needle movers to increase water re-use and recycling is in the area of tailings management. Within five to ten years at Goldcorp, it is envisioned that the need for wet tailings dams will be eliminated and that all new tailings facilities will consist of only filtered or dewatered tailings. Filtered tailings is developing into a mature technology with wide application in mine waste management. This paper describes a conceptual level evaluation on the transition from a slurry to a filtered tailings operation at the Cerro Negro mine in southern Argentina. Key benefits and challenges are highlighted.INTRODUCTION Goldcorp’s Cerro Negro operation is located in the Santa Cruz province in the Patagonian region of Argentina. Cerro Negro has been in operation since 2014 and commercial production was achieved on January 1, 2015. The processing capacity of the plant is 4,000 tonnes of ore per day and in 2016 produced 363,000 ounces of gold and 3.1 million ounces of silver (Goldcorp Inc., 2017). As the mine is located in a semi-arid area, it is important to evaluate technologies that could reduce freshwater consumption and maximize water re-use and recycle rates. The current tailings operation at Cerro Negro incorporates pumping of tailings slurry into a conventionally lined Tailings Storage Facility (TSF). Water is reclaimed from the tailings supernatant pond to the process plant via pumps, however, water losses occur due to evaporation and solution retention within the slurry tailings voids. Converting to a filtered or dewatered tailings operation would allow for increased water recovery prior to tailings disposal, and decreased water losses from evaporation and from retention in the tailings solids void space. This paper describes a conceptual level evaluation on the transition to filtered or dewatered tailings with the primary objective of moving closer Towards Zero Water."

Jan 1, 2017

By G. C. Hambleton

"The author has had wide experience in the reclamation of coal from coal mine waste dumps in the United Kingdom.The paper includes such topics as the processing decision and factors affecting processability; method of testing and appraisal; test data interpretation; historical influences in apppraisal; special contaminants and processing difficulties; methods of treatment; review of systems in use and their comparative economics; over-all system economics including excavation, handling methods, recovery system and shale disposal; effluent treatment; environmental considerations; alternatives to processing for coal recovery; light aggregate and cement usage; burned shale heaps; land reclamation; shale deposition for encouragement of vegetation by natural or artificial means; use of tailings fines; the environmental argument for action."

Jan 1, 1972

By A. I. A. Salama

The CANMET Western Research Centre (CWRC) has developed a hydrocyclone model simulation of dewatering and fine particle separation circuits. The simulation is based on an existing empirical model. Utilizing a cyclone manufacturer’s published data, some modifications have been developed and integrated into the model. Feed stream characteristics, cyclone mechanical dimensions, and operating conditions are used in the CWRC modelling simulation. The computer results are presented in 3D graphs and corresponding 2D maps showing the cyclone mass recovery, percent solids by mass in underflow and overflow, and cut size as functions of the cyclone apex diameter and cyclone throughput (i.e., inlet pressure or pressure drop). Results of the computer simulation have been used in the economic feasibility and design of several dewatering circuits in oil sand plants.

Jan 1, 2003

By Michael W. Russnak

Productivity and operating expenses are everything when it comes to judging how well your mine and company are doing. Stakeholders are always looking at these numbers and trying to understand if productivity is improving, if operating costs are trending downward and what you are basing your decisions on. o make improvements you first need to understand how you are performing. If you can?t get this basic information, you will never improve. You will not be able to make simple decisions related to maintenance, operations or production. Forget about planning, as you will only be guessing based on the numbers some stakeholder or your executive wants to see. The problem miners run into is not that the data doesn?t exist; it does, but typically it?s raw, it?s everywhere and its volume is huge. Today there is more on-board computing capability in shovels than we had on our desktops three years ago. Add other mobile equipment, plant systems and multiple OEM vendors to the equation and the challenge is daunting.

May 1, 2007

By J. D. T. Steyl

"This paper presents a phenomenological model of the rate of iron(III) precipitation in batch and continuous autoclaves at medium temperature operating conditions. The rate expressions are based on information obtained from the literature and experimentation at low and high pulp densities. Special allowance is made for the formation of surface nuclei, which appears to be promoted at a higher iron(III) precipitate surface area, especially in suspensions of lower terminal acidity. This leads to the formation of secondary particulates and provides the required link to simulate high pulp density leaching-precipitation systems, using low pulp density batch precipitation data. In particular, the model allows direct application of the simulation to the autoclave oxidation of iron-containing copper sulfide concentrates and provides a good estimation of the relative precipitation rate of hematite, the preferred product, compared to hydronium jarosite. Some interesting mechanistic understandings of iron(III) precipitation in autoclaves are further elucidated.INTRODUCTIONThe objective of this work is to describe the rate of iron(III) precipitation and the relative amounts of hematite compared to hydronium jarosite precipitation during batch and continuous chalcopyrite oxidation under medium temperature (MT) (~130 to 160ºC) autoclave conditions. Published information has not yet revealed sufficient mechanistic insights about this sparingly soluble salt system under these conditions. The rate expressions in this paper are based in part on current literature information, supplemented by qualitative experimental observation at low pulp density conditions, in particular the high-resolution backscatter electron (BSE) images and particle size distributions (PSDs) of the precipitates. A summary of this work and insights from the literature are presented first, after which the behaviour of iron(III) in high pulp density leaching systems is used to derive a phenomenological expression of the effect of existing iron(III) precipitate surface area on the precipitation rate. The overall regression encapsulates all the experimental results, i.e., those obtained in both batch and continuous autoclave configurations (Steyl, 2012a)."

Jan 1, 2012

By Roger T. Laine

"The Carswell structure, located in the western part of the Athabasca Basin, northern Saskatchewan, has been extensively explored since 1967. This exploration has been successful and lead to the discovery, in 1970, of the D sandstone-hosted unconformity related deposit. By the end of 1984, five additional basement-hosted unconformity related deposits had been delineated: the OP and N discovered in 1970, the Claude in 1971, the Dominique-Peter in 1981, and the Dominique-Janine in 1984. The D deposit has been mined out; the Claude open-pit has already produced more than 500 tonnes of uranium, the development of the Dominique-Peter underground mine (first phase) has been completed, and production from the latter started in 1985.All six deposits are located in the southern part of the Aphebian metamorphic core, 18 km in diameter, which has intruded at least 1250 metres of Helikian Athabasca Group sediments during a cryptoexplosion event at 480 Ma, unrelated to the emplacement of uranium mineralization. The metamorphic rocks, affected by the Hudsonian Orogeny, are divided in two lithostratrigraphic units: the Peter River gneiss, aluminous gneiss series, and the Earl River complex, mixed quartzofeldspathic and mafic gneiss series. A well developed regolith profile is recognizable in the south along the contact with the sandstone and inside the metamorphic core sometimes associated with conformable sandstone beds.Basement and sandstone-hosted uranium deposits show many similarities:-linkage to unconformity;-mineralogy and geochronology with a first phase mineralization characterized by a polymetallic sulphide-uraninite-brannerite assemblage dated at 1150 to 1050 Ma, a second phase characterized by a simple sulphide-uraninite assemblage dated at 890 to 820 Ma, and a third phase characterized by a pitchblende-hematite dated at 380 Ma; and,-linkage to early Hudsonian structures with remobilization of these structures during intense hydrothermal alteration resulting in Mg chlorite-illite halos."

Jan 1, 1986

By G. Reuben Yourt

IN 1935, Wright-Hargreaves Mines, Limited, initiated an enlarged programme of ventilation. In the mine, surveys were made from time to time by the geological staff, and improvements in ventilation were effected to accord with progress in mining as greater depth was attained. In the summer of 1938 an engineer was trained in the technique of dust sampling. Instruments and equipment for this purpose, such as konimeter, microscope, furnace, etc., were purchased, and a suitable office, equipped with laboratory facilities, was provided. The full time of the engineer is devoted to ventilation and dust control. On surface, in the mill crushing-plant and in the assay office and sample crushing room, an elaborate arrangement of hoods and exhaust systems has been installed to eliminate the dust. These installations, however, are not described in the present paper, which deals only with an extensive programme of underground ventilation as a method of coping with high dust concentrations, increasing temperatures and high humilities.

Jan 1, 1940

By C. Kuehmann, B. Tufts

QuesTek Innovations has applied its Materials by Design® methodology to computationally design a new ultra high-strength corrosion resistant steel. Ferriurn® S53 eliminates the need for toxic cadmium coatings currently used on conventional steels in landing gear systems. S53 has the strength of 300M steel, and corrosion resistance similar to 15-5PH stainless steel. S53&apos;s corrosion resistance improves stress corrosion cracking resistance and reduces susceptibility to hydrogen embrittlement, improving component reliability and providing an opportunity for extended overhaul and repair intervals. Ultimate tensile stress is 1965 to 2000MPa. S53 was designed to be mechanically equivalent to 300M, with the key addition of intrinsic corrosion resistance. Alloy design, microstructural characterization, and mechanical properties are discussed herein.

Jan 1, 2006

By F. Baczek, S. S. Rocks, D. Chaiko, T. Walters

The atmospheric leaching of chalcopyrite concentrates using acidic ferric sulfate lixiviants is well known to suffer from slow leach kinetics and poor copper recoveries. A number of approaches have been proposed for improving both leach kinetics and recoveries in this system. Many of these, while effective, suffer from high CAPEX and/or OPEX. As many mine sites begin transitioning from heap leaching of copper oxides to processing of primary copper sulfides, cost-efficient leach processes that are compatible with existing SX/EW processes will be needed to maintain existing cathode production. To this end, FLSmidth is exploring process options and reactor technology for the hydrometallurgical processing of primary sulfides. One approach that appears to be highly effective at increasing copper recoveries takes advantage of the enhanced reactivity of transitory, surface-defect structures generated during particle fracture. Significant process efficiencies are gained by matching the rate of grinding to the rate of electrochemical leaching in Mechano-Chemical leach processes. The patent-pending FLSmidth® ROL process uses a Stirred Media Reactor (SMRt reactor) to achieve copper recoveries of 97+% in 6 hours or less. This approach overcomes many of the surface passivation problems that have hindered other atmospheric leach processes. New insights to leach mechanisms are presented.

Jan 1, 2015

By Robert B. Parsons

"Canada&apos;s mining industry has reason to celebrate the federal government&apos;s budget which was tabled on February 26, 1986. The budget contains an important proposal to improve the flowthrough share rules by effectively eliminating the investor&apos;s liability to third parties. This proposed rule change and other important budget proposals are the subject of this month&apos;s edition of Tax Notes. IntroductionWhile Finance Minister Michael Wilson&apos;s February 26, 1986 budget received a mixed reaction from business and labour leaders, the budget was mainly ""good news"" for the mining industry. A long-standing bugaboo in the flow-through share rules will be cleared up, a permanent set of rules will be installed for the tax treatment of Northern allowances, and limited partnerships will apparently be able to continue to serve a useful role in financing exploration programs. Flow-Through SharesThe present rules which apply to an investment in flow-through shares are structured in such a way that the relevant Canadian exploration expense (""CEE"") must be incurred by the investor, and not by the issuing corporation. Obviously, in the case of most flow-through share issues, this requirement that the investor incur the CEE poses a practical problem-the investor typically does not have the expertise or organization to incur the CEE. As a result, an integral part of most flowthrough arrangements is an agreement whereby the investor appoints another party (usually the issuing corporation) as his agent to spend the flow-through funds on CEE on his behalf. Although the issuing corporation might consequently be the party which actually spends the flow-through share funds on CEE, nevertheless the legal structure is such that the investor is the ""principal"" who is incurring the CEE. As such, the investor is legally responsible for any third-party claims with respect to the exploration program. Third-party liability might arise, for example, in the case of property damage, personal injury, environmental infractions, and so on."

Jan 1, 1986

By Louis Cabot

A pilot plant of the Modular Gold Processing Unit (MGPU) was designed, installed and operated, over a 8 months period, by RSW-Béroma, at the Granada Mine located near Rouyn-Noranda, Quebec. A description of the project geology, plant set up as well as exploitation results, including productivity and profitability curves, are given for a small scale mining operation in comparison with larger ones. Copyright ã 2001 CIM

May 1, 2001

By J Zhou

Based on the mineralogical characteristics and mineral processing techniques required, gold ores can be classified into 12 types, including gold placers, quartz vein-lode ores, oxidized ores, silver-rich ores, iron oxide copper gold ores, porphyry copper gold ores, iron sulphide ores, arsenic sulphide ores, antimony sulphide ores, bismuth sulphide ores, telluride ores and carbonaceous sulphide ores. The bulk mineralogy and gold deportment of each ore type is different and may have a significant impact on ore processing and metal extraction. This paper summarizes the bulk mineralogy and gold deportment in some major types of gold ores and discusses the potential impact of gold deportment on gold metallurgy.

Jan 1, 2011

By L. E. Fischer

The background for the 630-million-dollar-plus iron ore project at Kudremukh is outlined. The system and plants for mining, crushing, concentrating, transporting via a slurry pipeline, filtering and shiploading 7.5 million metric tons of iron ore per year are fully described. The mode of operation and the problems encountered in such a transfer of North American technology to developing countries are analyzed. Difficulties encountered during construction are discussed and the progress milestones made over a two-year period are enumerated.

Jan 1, 1979

By A. E. Aho

"The material presented in this paper will be subject to modification as new data become available, but it is presented in the hope that it will inspire more intensive mineral exploration and geologic studies of what appears to be one of Canada's richest mineral provinces. A metallogenic province 400 by 150 miles in extent, lying mostly northeast of Tintina trench, encompasses most of the base metal deposits of Yukon, as well as deposits of other metals. Its main features are northwesterly trending arcuate fold belts, with several orogenic axes, which include most of the metamorphosed rocks, granitic intrusives and mineralization; and which are modified by regional uplifts, northwest-striking fault trenches, and lesser transverse folding and faulting.The main base metal occurrences and their regional controls are summarized briefly. Most of the replacement-type deposits are localized in late Proterozoic to early Paleozoic rocks, particularly Lower Cambrian -probably because these are the most physically and chemically favourable hosts encountered in an appropriate temperature and pressure environment; perhaps because of early age of deposition. Most of the deposits also occur near heat sources or intrusives with associated structural uplift, which has, moreover, served to expose the older rocks. They also tend to occur near known or suspected regional fault trenches, such as Tintina, Macmillan and Hess, although this relationship may be fortuitous. In detail, they may be localized in fold axes, flat-lying beds or other appropriate structural traps. Vein-type deposits are fracture-controlled and localized by dilational localfties, the competence of wall rocks and ""damming"" effects.In the Anvil district, large stratiform iron-zinc-lead replacement deposits lie parallel to gently plunging flex-ures in phyllite in a zone parallel to the Tintina trench, along the southwest flank of the arch-like Anvil batholith. About 80 million tons of massive sulphide ore probably existed before erosion of the Faro orebody, the Vangorda deposit could have been of similar magnitude before erosion and much more tonnage probably remains to be discovered in the district. The Anvil deposits may differ from others found to date in Yukon, but resemble the Sullivan orebody of southeastern British Columbia in their large size, localization in essentially non-limy peptic to arena-ceous host rocks of Proterozoic or early Paleozoic age and proximity to the Rocky Mountain -Tintina trench sys-tem. These features suggest an origin from primordial subcrustal sources.More major ore deposits, not only of lead, zinc and copper but probably of other metals as well, will no doubt be found in similar environments in Yukon or Alaska. Thus, the base metal province of Yukon offers challenging opportunities for prospecting, development, field studies and basic research."

Jan 1, 1969

ABSTRACT This paper details the work of RISKGATE, the largest Australian Coal Association Research Program (ACARP) occupational health and safety initiative to date. The program is an interactive online risk management system developed to maximize health and safety performance in the coal mining industry by implementing continuous improvement in managing major unwanted events. The comprehensive knowledge base covers tires, collisions, fires, isolation, strata control underground, ground control open cut, explosions, explosives, manual tasks, and slips/trips/falls. All major Australian coal mining companies contributed topic experts to this broad industry initiative: nine coal mining companies, more than 80 experts, and more than 400 days of individual time for knowledge-capture workshops.

Jan 1, 2014

By A. Mazhary

"Although sensor-based ore sorting has gained significant attention recently, sorting gold deposits still face a high level of skepticism by gold mining companies. In order to shed some light on the matter, this article looks at two different gold deposits that were examined using X-ray Fluorescence, Electromagnetic and X-ray Transmission sensors. The heterogeneity of each sample is measured based on the assay results of each particle and is related to its sortability. Multivariate linear regression analysis was also performed on the XRF results to find potential proxy elements for detecting gold. The results from these deposits were varied and each sample showed different levels of sortability. While both X-ray sensors proved efficient for different deposits, the electromagnetic sensor failed to produce any promising results. Despite unsatisfactory result for one sample, this technology can have significant advantages in terms of lowering the operational costs and improving head grades and recoveries providing that the deposit is amenable to such separation methods. Therefore, it is important to mention that sensor-based ore sorting is ore and sensor dependent, and as a result, it cannot be applied and be beneficial to all deposits. Therefore, amenability tests are required in order to examine the potential for sensor-based ore sorting before one can reject the idea.INTRODUCTION Although sensor-based ore sorting has gained significant attention recently, sorting gold deposits still face a high level of skepticism by gold mining companies. Except for a few cases presented previously, no new case studies have been published. Previously, mines such as Kloof Gold Mine in South Africa used an optical sorter to sort their waste stockpile in 2003–2004 (Von Ketelhodt, 2009) and then again in 2009 (Von Ketelhodt, Falcon, & Falcon, 2011). More recently, Coeur Operations utilized an XRT sorter for their Kensington Mine in Alaska (Lasley, 2014) and also Anglo-American Platinum used an XRF sorter to pre-concentrate Platinum Group Metals through an algorithm that used chrome, copper and nickel as proxies (Rule, Fouchee, & Swart, 2015)."

Jan 1, 2017