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By R. D. Lawrence

"Suggestions have been made that the appraisal of mining assets using discounted cash flow techniques should be based solely on proven and probable reserves in reliance upon the widespread international recognition of uniform resource definitions. Following a review of general accepted valuation principles, a survey of the literature and, most importantly, a review of real transactions in the open market, it is clear that valuators should not be constrained by the growing acceptance of modern mineral resource codes. On the contrary, valuation practitioners should be encouraged to examine all classes of mineralization and, after making due allowance for risk, to utilize all mineral resources as a basis for determining fair market value.INTRODUCTIONGreat strides have been made recently in achieving an international consensus on mineral reserve and resource definitions and classifications. The Australasian JORC code, the CIM code in Canada, the SME proposal in the United States and even a proposed code from the United Nations have all brought the objective within reach.Unfortunately, this success has led to another problem for mineral valuators. Certain securities regulators, tax collectors and their ilk have begun to expound on the opinion that discounted cash flow projections carried out to calculate net present values that would form the basis for a valuation determination should be based solely on proven and probable reserves. The author disagrees with this position. This paper examines the subject from four points of view:"

Jan 1, 2003

By R. Bainbridge

"IntroductionTHE LEAD SMELTING Department of The Consolidated Mining •and Smelting Company of Canada, Limited (Cominco), at Trail, B.C. treats materials from numerous sources for the recovery of lead, •and, of secondary importance, for the .recovery of sulphur as S02• The Department's sintering section has a .capacity of 1,500 tons daily. This section is being replaced by •a new charge-•handling and sintering plant with a daily capacity of 2,000 tons of finished sinter. Materials handled in the sintering section comprise concentrates, ores, and fluxes from Company mines and from 'custom' (independent) producers, together with intermediate products from various plants of Cominco'•s Metallurgical Division, all of which must be treated to, make up a chemically balanced charge of a predetermined lead content for the sintering plant.As received, 80 •per .cent of these materials are finer than 200 mesh, and one-quarter of the tonnage (dry basis) is a slurry .at 30 to 40 per cent moisture. This slurry, a -residue from the electrolytic zinc operation, was, for many years, partially dried before being mixed with other dry materials to make up the sinterplant charge.Some experimental work carried out in 1937 indicated that the metallurgy of the sintering operation could be improved by adopting a technique of 'wet-mixing' followed by controlled drying and nodulizing."

Jan 1, 1953

By H. R. Oliveira, C. R. Aragonez de Vasconcellos

Pipeline operation and maintenance necessarily involves geotechnical studies at points and areas with deflagrated instabilities or still to map and monitor areas prone to geotechnical problems. Landslides, erosions and debris flows are some examples of natural hazards, that not rarely, can bring high consequences to pipelines, sometimes leading them to high stresses levels and ruptures. Bolivia-Brazil Natural Gas Pipeline has 2.593 kilometers since Rio Grande City in Bolivia until Canoas City, in south Brazil. The pipeline crosses a lot of types of geological fields and difficult topography. The south spread of the pipeline has the most prone areas to geotechnical hazards because of its hard topography combined with the variety of geological materials, such as, colluvium deposits and debris flow areas. The aim of this paper is to present the right-of-way geotechnical risks that affect pipelines, presenting some practical remedial works done by TBG at Bolivia-Brazil Natural Gas Pipeline as well as the integrity plan and the adopted actions in way to prevent geotechnical accidents.

Jan 1, 2005

Since 2008 rapid advances have been made in technologies for the sensing and sorting of ores, particularly copper, and copper-related ores. Advances include significant increases in the sensitivity and throughput, specifically in the area of bulk sorting. Such advances were not possible without contemporaneous advances in the understanding of copper orebodies, in particular the understanding and quantification of the heterogeneity required within an orebody to support an effective sort, regardless of the technology deployed to do this. This paper covers fundamental knowledge in the characterization of orebodies and their ores for sorting; relationships between measures of heterogeneity and sorting response; the design of bulk sorting systems that can exploit this heterogeneity to add value to copper operations; and, a quantification of the value that can be generated from bulk sorting at a case study mine. INTRODUCTION Society currently puts increasing pressure on industries to move towards cleaner and more efficient means of production, and the mining industry is no exception. Mining additionally faces other factors increasing the pressure to be more efficient: high-grade and easily accessible reserves have become largely depleted, therefore the mined grade at operations across most commodities, including and in particular copper, is decreasing. Additionally, the grade of new discoveries in the sector continues to decrease (Schodde, 2011). Factor in the high capital cost of processing facilities and the low levels of efficiency of current grinding circuits, and the situation for such mines becomes dire. Sorting, by maximizing the amount of ore extracted while simultaneously reducing the waste content in ore delivered to downstream processes (whether simply transport and crushing, or more sophisticated circuits such as grinding and flotation or leaching) has long been of interest to mining operations and projects struggling with low margins (Bamber, 2012). However, until recently sorting technologies that are both cost effective and effective at such high throughputs have not been commercially available.

Jan 1, 2019

By K. Mirkhani, P. Gebski, W. Ying

The campaign life of an industrial metallurgical vessels strongly relies on the quality and quantity of the refractory lining. An operating furnace or converter refractory lining can be assessed either by thermal modeling or by acousto ultrasonic-echo (AU-E) technique or a combination. AU-E is a Non-Destructive Testing (NDT) stress wave propagation technique that has been utilized on a wide variety of smelting vessels for over 12 years with good success. AU-E can determine the thickness of remaining refractory lining, estimate the thickness of build-up or accretion, detect and locate metal penetration and impregnation into the lining, and identify hydrated or cracked areas of refractory. This paper details the AU-E principles, equipment and recent improvements to the data analysis to further improve speed and accuracy. In addition, the paper discusses the AU-E accuracy and limitations through a diverse and vast array of practical examples including a comparison with thermal modeling and physical measurements.

Jan 1, 2011

By S. P. Chong, N. C. Shih, G. A. Turner

Fine powders, with the bulk of the particle diameters Jess than 10 microns, were aerated so that each particle was, on the average, separated from its neighbours by 1.3 to 2 mean diameters. In this state, measurements were made of the viscosity and settling rate of the powder, and the interfacial tension between it and a moist pellet. From the viscosity measurements, qualitative analogies are drawn between the behaviour of the aerated powder and that of a dense gas near its critical point.

Jan 1, 1970

By V. S. Sastri, Elboujdaini. M.

"Economics of wear in mining industry and methods by which wear cost may be reduced will be discussed.IntroductionCanada loses more than $5 billion annually due to friction and wear (Table 1). It is estimated that about $1.3 billion, or about 25% of the losses, could be saved through better application of existing technology (Table 2). It should be noted that the costs given in Table 1 and 2 refer to 1986. The losses due to friction and wear and the savings would be much higher in 1996. Tribology combines the many branches and specialties in science and technology concerned with understanding and combatting friction and wear. Specifically, tribology is concerned with the design and manufacture of sliding and rolling bearings, piston rings, gears, cutting tools and other devices in which surfaces interact, in sliding or other relative motion. Tribology is concerned with the correct use of materials for interacting solid surfaces, with the interaction of the surfaces with the lubricants, with the chemistry, physics and use of lubricants. It is concerned with the reduction of friction and wear and the avoidance of associated failures in machinery. Similar tribological components such as bearings are used in different technologies and similar tribological problems such as abrasive wear occur in different industries. Thus, tribology is in itself a generic science and technology, concerned with the generation and dissemination of knowledge on friction, wear and lubrication, and the application of the knowledge, to a wide range of industrial products and equipment, from ploughs to space equipment, from prosthesis to engines, from washing machines to railways, from computers to power stations, from paper mills to mines. Avoidable losses due to friction and"

Jan 1, 1997

By Dogan Paktunc, Larry J. Hulbert, Robert C. Carne, D. Conrad Gregoire

A thin layer of stratiform Ni-Zn-PGE sulfide mineralization of sedimentary-diagenetic origin was deposited during the Middle to Upper Devonian in the euxinic "Nick basin". The mineralized unit (=3 cm thick), which seems to have been developed over the entire sedimentary basin of > 80 km2, consists of pyrite, vaesite (NiSz), and sphalerite. The average grade of the mineralization is about 5.30/0 Ni, 0.73% Zn, =770 ppb (pGE+Au), and up to 61 ppm Re. Anomalous Se, As, Mo, P, Ba and U are present. A minimum of 0.90 x 106 tonnes of Ni were deposited in the basin (based on a bed thickness of 3 cm) during the Devonian. The unique metal association, extensive lateral distribution, persistent metal grade, mineralogical makeup, and stratigraphic control demonstrate that this is a new deposit type and a new geological environment for Ni and PGE + Au. The sulfide layer occurs at the base of a Phosphatic Chert Member which is underlain by a distinctive marker unit consisting of concretionary limestone structures. The limestone spheroids may represent a vent-specific carbonate facies developed adjacent to faults that emanated nutrientrich hydrothermal discharges just prior to the main mineralizing event. The suite of elements associated with the Nick mineralization suggests that the ore-forming metals were originally bound to organic matter derived from decaying marine organisms. Discharge of hot brines bearing organic matter-bound metals took place along numerous conduits within basin faults that are now manifest as bitumen veins. Our syndiagenetic model proposes that these fluids were discharged laterally from the conduits into the unconsolidated bottom sediment (ooze). The introduction of this metalliferous fluid, rich in organic matter, stimulated biological activity and bacterial reduction of its contained 804 to sulfide. Hot, dense, laterally migrating hydrothermal fluid precipitated thin sulfide-rich larninae within bottom sediment. Published thermodynamic studies suggest that the diagnostic vaesitepyrite assemblage crystallized at approximately 138°C. The 034S values range from -14.7 0/00 to -10.00/00 and are up to 340/00 lighter than locally surrounding sulfides and age-equivalent mineralized strata elsewhere in the Selwyn Basin. The Ol3C values of calcite in the footwall of the mineralized unit (- 12 0/00 to -6 0/00) are isotopically much lighter than regional values. The lighter isotopic character is attributed to the hydrothermal discharge of fluids enriched in organic compounds. Although geochemical profiles of the lower Earn Group sediments that host the Nick mineralization reveal that these black shales are not distinctive, the unusual Ni, Zn, PGE, U, Ba, and P elemental associations and their anomalous concentrations in stream sediments can be used to explore for this deposit type.

Jan 1, 1992

By A. McEachern

At the Annual Meeting of this society, held in Halifax last year, a paper entitled "Closed System Breathing Apparatus" was read by I. C. Mackie, metallurgist, British Empire Steel Corporation. Coming from such an authority it was most instructive and illuminating. The purpose of the paper was to emphasize the necessity of a full supply of oxygen and the danger of oxygen shortage in the use of rescue breathing apparatus. In connection with this he pointed out: "In times of emergency, when life is at stake, rescue men cannot be restrained from using their utmost endeavor, and unless the apparatus is adequate to meet the heaviest load, the result may be fatal to the wearer. The body's demand for its oxygen requirement is absolutely imperative and must be granted at once. We can do without food for many days and without water for many hours, but we cannot do without full requirements of oxygen even for a few minutes. Furthermore, the victim of oxygen shortage gets practically no warning. He may fall helpless or unconscious before realizing that he is in a serious condition." Hence the necessity for expelling all the nitrogen from the breathing-bag and filling it with pure oxygen; also filling the lungs of the wearer with oxygen before he begins to use the breathing apparatus. This practice is general at all the collieries under the British Empire Steel Corporation.

Jan 1, 1924

By H. Lundberg

Introduction The world has been suffering from an excessive production of all kinds of raw materials, and the metals and petroleum are no exception. As a consequence, at the moment, the urge to find new mineral deposits is almost non-existent and prospecting languishes. But from previous experience we know that sooner or later new supplies will be needed. Mineral deposits become exhausted, and to keep up the supplies of our metals and petroleum, new deposits must be found. Even now, a supply of petroleum of domestic production would not be unwelcome in Canada. It is not, therefore, so entirely malapropos to discuss means of finding ores and oil as it would seem. Almost any physical property connected in definite manner with minerals and rocks may be made the basis of geophysical exploration. This is particularly true of electrical resistivity, and its utilization in electrical prospecting has been the deciding factor in the discovery of such big ore-bodies as Buchans mine, Newfoundland, and the large copper ore-bodies in northern Sweden, etc., as well as in the solution of many foundation and structural problems. The importance of electrical prospecting has been growing steadily, and already there exists hardly any exploration project involving geological problems which may not profit by its application. Electrical prospecting is marching on, and neither temporary failures, nor incompetence, nor over-optimism, nor ill-will and pessimism, nor bad times and business depression, will be able to halt its progress.

Jan 1, 1931

An essential tool for every step ? Early field survey ? Handheld satellite phones ? Portable satellite phones ? Exploration and Drilling ? Handheld satellite phones ? Portable satellite phones ? Production ? Handheld and portable ? Fixed Satellites systems ? Asset tracking systems Main applications via satellite ? Voice and Fax communication ? Internet access and E-mail ? Video conferencing ? Interconnection to mobile phones, 2 way radios, long range WIFI ? Equipment Tele-maintenance ? Telemedicine ? Crew and morale calling ? Vehicle and asset tracking

May 1, 2006

"The QEMSCAN system is the third generation of automated mineral analysis systems that began with the QEM*SEM at CSIRO 30 years ago (Butcher et al. 2000). It is now a successful commercial instrument with 39 instruments in operation around the world. Back Scattered Electrons (BSE) and Energy Dispersive (EDS) X-Ray spectra are used to create digital mineral images with mineral identification occurring online. Low-count EDS spectra are used preferentially to BSE brightness, allowing minerals to be accurately identified by chemical composition. Individual minerals or groups of similar compositions are identified by comparison to a comprehensive mineral database incorporated into the QEMSCAN software. Optical mineralogy and Scanning Electron Microscopy is a metallurgists’ tool for determining the ore process mineralogy and delivering a better flowsheet. These techniques have limitations, provide limited information and sometimes fail to provide representative information. In contrast, QEMSCAN provides information on the nature and occurrence of all mineral species present plus the liberation characteristics, looking at thousands of particles in the sample presented. Some of the data presented includes:• Particle and grain sizes• Dominant mineral species• Particle shape• Calculated metal content• Density• Deportment of elements of interest between the mineral phases• Quantitative mineralogy• Mineral associations, locking and liberation• Textural relationships (particle images)It can also be used on concentrates, polished sections or drill core. This is a significant improvement in ore characterisation providing lithology, mineralogy, liberation, ore grade and porosity from a sample. Theoretical grade-recovery curves can be created to be mineralogically limited from QEMSCAN analysis which, when compared with metallurgical results, are valuable in evaluating whether liberation or chemical selectivity is driving flotation performance. A number of case study examples are given where the QEMSCAN had a significant bearing on future project development at an early stage of exploration and mine development."

Jan 1, 2012

By Peter Cunningham

Teck Facts and Figures ? Employ more than 14,000 around the world, includes: ? Over 8,600 in Canada (close to 7,800 in British Columbia) ? Close to 2,000 in Chile ? Over 2,700 in Peru ? Approximately 600 in U.S. ? Hundreds more in exploration around the world ? Total capital expenditures ? $1.8 billion for 2012

Aug 1, 2013

By David E. Pearson

"Western Canadian coking coals are located in the Rocky Mountains arid foothills of British Columbia and Alberta. They are typical of non-marine coals, characterized by total sulphur contents of less than one per cent and with ash contents of 10-30 weight per cent. This mineral matter is composed principally of kaolinite and quartz.The petrographic compositions of most of the coking coals which constitute the 2.065 billion tonnes of British Columbia's measured reserves, and the compositions of the metallurgical coal currently exported from Alberta, show them to be rich in the inertinite macerals, macrinite, fusinite and semifusinite. When the mean maximum reflectance of vitrinite in oil/Romax) is used as the coal rank parameter, this high inertinite content is reflected in the lower volatile-matter yields, but the relatively inert character is also displayed by lower free swelling indices (PSI), lower maximum dilatations, lower maximum fluidities and lower coke strengths than other coals of the same rank, but richer in the reactive macerals, vitrinite, exinite and semifusinite. Despite these reduced values in the so-called caking tests, inertinite-rich coals produce strong coke.A system of classification of coking coals is introduced which is based on rank, as indicated by Ro max, and either petrographic composition, maximum dilatation, maximum fluidity or, to a lesser extent, PSI and volatile-matter yield. Six principal coal groups can be distinguished among coking coals using this versatile classification. Inertinite-rich coals are assigned to the Keystone Group (GI), Balmer Group (G3) or Moura Group (G4), each group being named for a coal typical of that population ofcoals. Reactive-rich coals are assigned to the Pittston Group (G2), Kellerman Group (G5) or Big Ben Group (G6). A multiple-regression analysis of coal quality versus price shows how the value of coking coal in the Japanese market appears to be related to reflectance and the free swelling index, and confirms the economic viability of the classification.British Columbia's measured reserves of coking coal contain representatives of four of these groups; Balmer Group (73%), Moura Group (/6%), Pittston Group (3.4%) and Kellerman Group (7.6%).This analysis of the quality of Western Canadian coking coal indicates that despite the need for large proportions of inertinite-rich coking coal in blends produced in the Japanese steel industry, there is nevertheless a demonstrated overabundance of Balmer Group and Moura Group coals available to the international coking coal market."

Jan 1, 1980

By J. G. Pearson, F. H. MacDougall, A. G. Galley

The difference in age, host rock lithology, alteration and style of mineralization indicates a fundamental difference in the format ion of gold deposits in the Flin Flon and Amisk Lake areas. The Flin Flon area contains early quartz-sulfide-gold veins fo rmed within intermittently active fractures and later plutonic hosted deposits thought to be generated in a porphyry system. In the Amisk Lake area two types of gold occurrences are recognized: I) gold-quartzcarbonate- sulfide veins within or flanking fault zones and 2) structurally and stratigraphical ly controlled zones of dissem inated and vein type sulfide-gold mineralization within extrusive and intrusive rhyolite and dacite porphyries. Both types of deposits are set within supracrustal rocks. are accompanied by intense alteration haloes and were formed prior to the major deformation event suggesting an early, epigenetic hydrothermal origin.

Jan 1, 1986

By G. Avramovic-Cingara

Grain boundary characteristics and microstructural evolution are analyzed in a comparative study using orientation imaging microscopy (OIM/SEM) and transmission electron microscopy (TEM/SAD). The subgrain sizes and misorientations were determined by the OIM for aluminum deformed in torsion to equivalent strains between 0.2 and 4 over the temperature ranges of300-600°C and strain rates 0.01-1 s". The OIM gives clearer evidence of boundaries with high misorientation than does TEM, but it overestimates their frequency b y missing boundaries less than 1 0. T EM more clearly reveals low-angle arrays of widely spaced dislocations resulting in finer subgrain sizes than those indicated by OIM. The evidence supports a mechanism combining dynamic recovery (DRY), deformation band formation with permanent boundaries and geometric dynamic recrystallization (gDRX) in contrast to the hypothesis known as continuous dynamic recrystallization (cDRX).

Jan 1, 2004

By F. E. Lathe

RECENT events have emphasized with renewed force the well known fact that war greatly intensifies the demand for certain metals, particularly for iron, copper, and zinc. Any increase in the use of iron and steel, whether in war or peace, is also accompanied by increased consumption of those metals which find their chief application as ferro-alloys, such as nickel, chromium, manganese, molybdenum, tungsten, and vanadium. Further, since high temperatures are essential for the production of all these metals, activity in the metal industry is inevitably accompanied by an insistent demand for refractories. For example, in North American practice the consumption of magnesitic hearth refractories is frequently expressed in pounds per ton of steel. This quantity (not including straight dolomite) ranges on individual plants from about 7 to 12 pounds. When the industry is operating at approximately full capacity, the ratio of refractory to steel tends to increase, since the tonnage of steel produced is recognized as of paramount importance, and this leads to the harder driving of furnaces and less regard for the effect on refractories. It should also be observed that the cost of refractories per ton of metal produced is always so low, in comparison with other items, that it may even increase while the cost of metal per ton is being reduced through more continuous operation and the use of higher temperatures. As one prominent Canadian copper metallurgist has tersely expressed it, he is "not in business to save refractories but to smelt ore". The effect of war demands and of general industrial activity upon the production of basic and neutral refractories is clearly shown in Figure 1, which gives the value of chrome ore and magnesitic-dolomite produced in Canada during the period 1907 to 1937. Tonnages have not been shown, as these are not available for the full period; such figures as have been published from time to time are not strictly comparable, since both raw rock and finished products have on occasion been included. The preliminary figures for 1938, which are now available, have been prepared by the Dominion Bureau of Statistics on a different basis from those immediately preceding, and have therefore not been shown.

Jan 1, 1940

By Charlie Harper

Open Pit Mining of Golden Band Resources? EP Gold Deposit Golden Band Resources Inc. (GBN:TSX-V) is Saskatchewan's newest Gold Producer. Located in the La Ronge Gold Belt of northern Saskatchewan, GBN has over 875 km2 of claims with 12 known gold deposits and 4 former producing mines. Production has begun at the Roy Lloyd Mine (Bingo Deposit), to be followed initially by our EP and Komis properties. Development of the underground infrastructure at the Roy Lloyd Mineis continuing and on schedule. Production from these deposits will feed our centrally located and 100% owned Jolu mill. We have our provincial environmental permits in place, and we have an established infrastructure including a 400 tonne-per-day mill, year-round road access, and access to grid power. Construction of the grid power line and the above ground tailings facility are now complete.

Nov 1, 2011

By Hans E. Madeisky, Bruce W. Downing

The acid rock drainage (ARD) buffering capacity of mine waste is governed by its bulk chemical composition and its mineral assemblage. Conventional acid base accounting (ABA) tests can be used to predict short-term buffering, but should be used with caution to model or predict the long-term ARD buffering capacity of mine waste. ABA data for mine waste samples from four different deposit types: an orthosite-hosted magmatic sul?de nickel, dunite-hosted magmatic sul?denickel, porphyry copper-gold, and volcanic-hosted high sul?dation epithermal silver, were compared with whole-rock geochemical and petrographic data obtained from the same samples. Our objective was to devise and test a method of predicting ARD buffering capacity based on bulk chemistry and modal mineralogy. In other words, we developed a quantitative theoretical method for calculating neutralizing potential, relying on easily obtainable and relatively inexpensive whole-rock and sulfur XRF analyses, which could substitute for conventional ABA procedures in situations where these procedures are either too costly or too time consuming. For each deposit type, models were devised that reasonably approximate the net neutralization potential estimated by the ABA data obtained from laboratory tests. Once an appropriate model has been developed and tested, portable X-ray ?uorescence equipment, already used for grade control at many mine sites, could provide the whole-rock and sulfur analyses required to estimate the ARD potential of the waste material. Although this approach is not intended as a substitute for the legally mandated ABA test procedure, it could facilitate the timely and cost-effective management and mitigation of ARD at a mine site.

Jan 1, 1997

By F. Channier

The paper provides the most recent information on the construction of the AP60 phase 1 plant of Jonquiere which is due to be commissioned and started up in the first quarter of 2013. HSE management on site by RTA, and cooperation with local equipment manufacturers and contractors of the Saguenay-Lac Saint Jean region are highlighted in this section. The AP60 phase 1 Jonquiere plant aims to demonstrate of the AP60 technology at an industrial scale and allows the further developments of the AP60 cell. The advantages of the AP60 cell technology in terms of productivity, power consumption and environmental footprint are also briefly presented in the paper.

Jan 1, 2011