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By Ian R. Muirhead

Over the past year or so, a number of mining companies have been meeting to examine the role of research in surface mining and, in particular, how to establish a collaborative research effort for the surface mining industry. A review has been completed which has identified the topics that are of interest to the surface mining companies for undertaking collaborative research. This has identified key subject areas such as Operations & Equipment; Maintenance; Environment & Reclamation; and Stability. Specific research projects for the initial research effort have been selected which include Wireless Data Communications, Analysis and Management; Application of GPS in Mining; and Tires for Heavy Haulers. In addition, attention has also been focussed on finding a suitable low cost, but effective, organization to coordinate and manage the collaborative research. The recently formed CONRAD Organization (Canadian Oilsands Network for Research and Development) appears to be a suitable candidate and discussions are ongoing with that group. This paper provides a summary of the review of surface mining research needs and of the status of the establishment of a collaborative research body for surface mining.

Jan 1, 1996

By Daniel Hodouin, Claude Bazin, René del Villar

"A traditional linkage has long been established at Laval University's Department of Mining & Metallurgy between the Mineral Process (MP) and the Mining Exploitation (Min) on one hand, and between the Extractive Metallurgy (EM) and the Materials Engineering (Mat) on the other. This academic separation of Mineral Processing from Extractive Metallurgy at the educational level has become increasingly at odds with today's industrial practice in which both disciplines are not only complementary but also often intertwined. For instance, in gold ore processing, comminution, flotation, and gravity separation units are interfaced with atmospheric or pressure leaching modules and with carbon adsorption and electrowinning units. The new copper plants in South America combine comminution and flotation circuits with heap leaching, solvent extraction and electrowinning processes.In order to reflect this new industrial reality and to harmonise the options offered in both its engineering programs, the Department of Mining and Metallurgy of Laval University has introduced major changes in its curriculum in 1996. These changes reflect also the recognition that the somewhat secondary status given so far to Mineral Processing and to Extractive Metallurgy within their ""mother"" programs, Mining/Mineral Engineering and Materials metallurgical Engineering respectively, was in sharp contrast with their actual significance for the Canadian economy. Leading industrial voices have raised similar concerns and the Canadian Engineering Accreditation Board has also addressed this problem in its latest program evaluation.The changes implemented at Laval aimed at a) better representing MP and EM within the two undergraduate programs; b) training top-level versatile and multidisciplinary engineers, fluent in all aspects of MP and EM, irrespectively of which of the two ((mother)) programs they had chosen and capable of meeting today's industrial requirements; c) training students in process analysis, optimisation and automatic control using state-of-the-art software, and d) taking into account the co-operative nature of both undergraduate programs.Results are very encouraging in terms of student enrolment and industrial response. However, some concern is expressed on the sustainability of the renewed curriculum considering the drastic budget restrictions in effect at Laval as in most other Canadian universities."

Jan 1, 1999

By Brian Hart, Stamen Dimov

"The Time of Flight Secondary Ion Mass Spectrometer (ToF-SIMS) is unique in that it measures the outermost atomic layers of any material. The technique is particularly suited for determining surface chemical composition of mineral particles. It is most commonly used as a diagnostic tool to measure mineral surface chemical variability in plant and bench top flotation separation processes. Recently, research towards understanding the full capability of the instrument has resulted in the development of new diagnostic applications related to various Au extraction technologies and the development of the ToF-SIMS as a predictive tool for assessing the chemical reactivity of the ore.In this paper we will present a brief review of the ToF-SIMS technique with recent advances in instrumentation and methodologies including:•,?recent developments and advances towards a semi-quantitative approach to the evaluation of mineral surface modifiers (ex. Cu),•,?flotation case studies investigating activator, depressant and collector loading variability within a flotation process,•,?the recently developed chemical reactivity test which we believe has the potential to predict the behaviour of minerals in a flotation test in response to chemical transfer during grinding,•,recent applications for determination of surface Au preg-robbed in carbonaceous materials.A portion of this material has been recently presented at the COM 2009 meeting and at SIMS XVII (see Dimov et al 2009 and Hart et al, 2009).INTRODUCTIONIn flotation seperation surface chemistry is the principal determinant for selective separation of the various mineral phases (Ralston, 1994, Smart et al, 2003). Determination of this hydrophobic/hydrophilic balance by particle therefore requires correct identification and selection of the particular mineral phase(s) followed by a statistical analysis of the surface chemical characteristics of the particles with an estimation of the spread of values (Smart et al, 2003)."

Jan 1, 2010

By M. Schmidt, P. Nord, M. Larinkari

Cathode stripping machine technology has been developed significantly both in electrorefining (ER) and electrowinning (EW) applications in the last ten years. The main driver has been robotic cathode handling, which has enabled increased flexibility to meet different layout and material handling requirements for both ER and EW processes. Additionally, cathode stripping stations have been continuously developed to optimize speed and to reduce mechanical stress of permanent cathodes. 'taco' type cathodes have been proven as beneficial approach for high capacity operations (particularly in Cu ER), where over 600 cathodes per hour continuous throughput has been achieved. However, the latest developments also apply to split type cathode stripping. Besides material handling, the modern cathode stripping machine has also an important role to provide information for production and quality monitoring. This paper describes the latest developments from the field of copper cathode stripping based on several different projects implemented in the recent years. INTRODUCTION After introduction of the permanent cathode technology in the late 1970s, it became the prevailing technology in copper refineries over the traditional starting sheet process by the end of 1980s. The main driver was less labour-intensive production due to fewer processing steps required along with more automated electrode handling equipment (cathode stripping machine, anode preparation machine, anode scrap washing machine and tankhouse cranes). Since then the design of the cathode stripping machine has followed the development of permanent cathode technology. The main development steps so far can be summarized as follows: Full Deposit Stripping Machine (FDSM) based on waxed permanent cathodes or cathodes with bottom edge strips resulting in split cathodes (copper sheets separated, see Figure 1) Wax less cathode stripping based on V-groove on bottom of the edge strip resulting in either ‘taco’ cathodes (enveloped copper sheets, see Figure 1) or split cathodes Full Deposit Robotic Stripping Machines (FDRSM) using 1–5 robots for permanent cathode handling and cathode stacking.

Jan 1, 2019

By Jochen Petersen, Diane Taggart

"At an average of 90.3% (for the period of 1 January 2009 to 30 September 2011), Zincor’s zinc recovery was well below the industry standard of 96%. The losses through the residues, in particular the iron residue, were the biggest contributors to the overall zinc loss. It was believed that this loss could be decreased with the implementation of seed recycling. A plant trial was run to test the implementation of a seed recycle. The rate of seed addition through recycle was increased over a 4-week period. The presence of seed decreased the insoluble zinc loss by providing additional surface area for iron to precipitate onto, and reducing coating of unleached neutralising agent. The soluble zinc loss was also decreased at low and moderate seed recycle volumes. The improvement was attributed to agglomeration growth of the recycled particles, which improves the dewatering characteristics of the precipitate. In contrast, the soluble zinc loss increased at high seed recycle rates. This result was attributed to particle crowding and a low wash ratio.INTRODUCTION The Zincor refinery, which closed in December 2011, was situated just outside of Springs in the Gauteng Province of South Africa and employed the conventional Roast-Leach-Electrowin process, which accounts for 75 to 80% of the annual primary zinc production in the world. The refinery fed up to 220 000 t/a of zinc sulphide concentrate. The major portion of the raw material was sourced in Southern Africa from the Rosh Pinah and Black Mountain mines. Between 20 000 and 40 000 t/a of material was imported to make up the deficit and to improve the grade of the feed material. The iron contained in the zinc concentrates, at an average of 6.03% (for the period of 1 January 2009 to 30 September 2011), resulted in the formation of zinc ferrite during roasting, which is insoluble under atmospheric leach conditions. At Zincor, most of the zinc ferrite was dissolved in the residue treatment plant at elevated temperature and high acid strength. The leach liquor from this aggressive leach contained between 15 to 30 g/L of iron, mostly in the ferric form, and was known as the hot iron solution (HIS). The presence of iron in the liquor had an adverse effect on the zinc operation, particularly on the current efficiency in the electrowinning circuit. Therefore the iron needed complete removal."

Jan 1, 2016

By G. S. Crawford

Forecasts prepared by the B.C. Research Council for the National Harbours Board suggest that mineral shipments through B.C. Lower Mainland port facilities will increase more than four-fold, from 6 to about 25 million tons, during the decade 1965 to 1975. The longer term outlook is for a six-fold increase to about 35 million tons by 1985. In 1967, minerais accounted for more than one-third of the total deep-sea traffic tonnage, nearly as much as grain. By 1975, the minerals' share will be about half the total. The principal items are exports of potash from Saskatchewan, and of coal and sulphur from Alberta and British Columbia. Additional exports include copper and other mineral concentrates and propane. Imports are chiefly salt and phosphate rock. Coastal traffic in such items as cement, sand and grave!, and limestone totalled 3.3 mil-lion tons in 1967. They will continue to be of major importance, but do not have the spectacular growth potential of the deep-sea traffic.

Jan 1, 1968

By Catherine T. Ziten

Introduction ?Environmental assessments required for permitting ?Focus on ammonia produced through mine construction & blasting ?Water quality guidelines: federal, provincial, IGO ?Reported values are typically estimates from other projects ?Predictive modelling of ammonia aimed to assist planning

May 1, 2009

By Hassan Ghaffari

? HPGR Process/Overview ? HPGR vs. SAG ? The Manufacturers ? Mine Operations using HPGR ? Projects by Wardrop/Tetra Tech ? Economic Benefits ? Questions Main Operating Parameters ? Press Force (N/mm2) ? Roll Speed (m/s) ? Moisture Content (%) ? Feed Particle Size Distribution Specific throughput M* = throughput/D*L*V (ts/hm3) Flake thickness/strength in balance with the compressing force (floating roll situation)

Aug 1, 2013

By W. P. Campbell

Introduction OWING to the necessity of curtailing the length of this paper, nothing like an exhaustive treatment of the subject will be attempted. Instead, merely a few aspects will be considered, viz., water trouble in wells, sampling of waters, analysis, methods of reporting analysis, and the comparison of a few typical waters. The waters discussed will not be confined to those occurring in areas where oil or gas has already been found, but will include samples from areas in which drilling is being carried on in the hope that oil or gas may be found, i.e., from unproved fields. The Water Problem The problem of dealing with water encountered in oil and gas producing areas has engaged the attention of petroleum engineers from the early days of the industry. Water was not always considered a menace to oil sands; indeed, a certain amount of it was considered beneficial in some areas, but if such exist today they are very exceptional. In some fields, the problem is more acute than in others, and at times has baffled all attempts to solve it satisfactorily. Wells have been brought-in with promise of good production, but after a brief period have 'gone to water'. Whether ?it has always been a case of poor engineering in the form of unsuccessful water shut-off of 'top' or 'bottom' water, or because 'edge' water was present and water and oil were in such close contact it was impossible to remove the one without the other, is hard to say.

Jan 1, 1929

By Nathan P. Schmidt

Climate and hydrology data are required during all phases of mining projects, including impact assessment, mine planning and design, operational water management and mine closure and reclamation design. In the Canadian north, data sources are spatially sparse and often short-term in nature, and design parameters are often estimated based on data collected at sites far distant. Confidence in such data can be increased by verification or modification using data collected during properly implemented baseline and operational monitoring programs. A data set that accurately reflects conditions at the project is more readily accepted by regulatory agencies during the permitting process, and allows development of more effective and economic water management, mitigation measures and compensation. Data requirements and collection methods for developing an adequate data set for mine development are reviewed. These are illustrated using examples from oil sands, diamond and metal mines in the Canadian north.

May 1, 2004

By E. V. Konopleva, H. J. McQueen, V. M. Khlestov

In addition to increasing grain boundary area during hot working of austenite, the dislocation substructures create potential sites for nucleation of ferrite both at original grain boundaries and at transition boundaries between deformation bands. This development gives rise to a marked increase in the rates of nucleation, of growth and of transformation to ferrite. The combined net effect is product grain refinement that requires less stringent cooling between finish rolling and coiling; hence determination of the above rates would advance process optimization. The important control parameters are the preheat temperature (degree of homogenization), finishing temperature, strain (accumulation near finishing) and the extent of recrystallization after finishing. These effects vary greatly with steel composition; nevertheless, some general rules have been formulated. Moreover, there is also potential for deformation of the refined ferrite. There are other thermo-mechanical processes such as warm forming of metastable alloy austenite to provide a dense substructure that is carried into the martensite on quenching. In other processes, the austenite may be deformed during cooling through the transformation to develop a dense substructure in the ferrite that is stabilized by fine carbides.

Jan 1, 2004

By B. McHenry, A. E. Wraith, P. J. Mackey

The Wallaroo smelter on the Yorke Peninsula, South Australia commenced smelting operations in 1861 treating ores from the nearby Moonta and Kadina mines. The plant expanded and modernized on several occasions and was a leader in the successful introduction of new technology to improve operations. It operated continuously until 1923 when local mines became exhausted; in the closing stages of the 19th century it was the largest copper smelter in the world outside of those in Swansea, Wales. In 1892 a small electrolytic refinery was established at Wallaroo, the first in Australia, based on principles developed by Elkington at Pembrey, Wales in 1869. The Wallaroo refinery was specifically built to recover gold and silver from copper produced by smelting gold-containing feed materials shipped from Western Australia. This first venture into electrolytic refining was replaced in 1903 by a somewhat larger refinery which, although modest in size for its time, with a capacity of about 1000 tonnes of cathode copper per year, was very productive in precious metals. Anode copper was produced by an updated version of the reverberatory-based Welsh process until 1910 when barrel-type pneumatic converters were introduced based on American practice; subsequently, anodes were cast by tapping the precious-metals rich "bottoms" portion of converter copper as produced at about one-fifth into the copper blow. The present paper describes the Wallaroo refinery, its anode supply and products, supported by initial observations on a sample of a Wallaroo cathode held in the collection of the South Australia Museum, Adelaide SA, Australia. INTRODUCTION Australia ranked 6th in the world for copper mine production in 2018, with an output of 918,000 tonnes of mined copper, after Chile, Peru, Congo, China and the USA; about 40% of Australian mined copper was smelted in the country. Interestingly, the world ranking of Australia in mined copper has, with a few variations, remained about the same for more than 100 years – of interest, it was also the 6th largest country for copper production at 21,089 tonnes in 1899. At that time, all or most of the copper was smelted in the country (Mackey, 2016). Copper was first discovered in Australia in 1842 in South Australia not far from Adelaide; additional copper discoveries in the region soon followed. At first, copper ore was shipped to Swansea, Wales for smelting (Bampton, 2003). However, in addition to the long, 150 day one-way sea passage, it seems Welsh smelters preferred higher grade of ores – these aspects and likely a mood in the new colony to be independent of Swansea (Evans, 2014) evidently encouraged local smelting at the mine sites using small, Welsh-type reverberatory furnaces fired with hardwood as fuel and operated by Welsh and Cornish migrants. The first large copper smelter in Australia commenced in 1848 at Bremer, near Callington some 60 km east of Adelaide. With larger discoveries on Yorke Peninsula, the Wallaroo copper smelter at Wallaroo Bay on the west coast of the peninsula commenced operations in 1861 (Bell & McCarthy, 2008). Thus began one of the most successful, and in its day, one of the most advanced and innovative plants in Australia if not the world. In the late 1860s, it was considered one of the largest copper smelters in the world (Bell & McCarthy, 2008)

Jan 1, 2019

By C. E. Baltzer

This is the fourth in a series of coal technology reviews being prepared. in accordance with a recommendation voted by the Coal Division C.I.M. in session at the Jubilee Meeting, Vancouver, 1948, that the Department of Mines and Resources be requested to arrange for publication by the proper Government authority of a Quarterly Review of Coal Technology for distribution among those concerned in the production and use of coal in Canada. Copies of the first review, which appeared in the November, 1948, BULLETIN, pp. 612-614, of the second review in the June, 1949, BULLETIN, pp. 272-275, and of the third review in April, 1950, BUL-LETIN, pp. 1,9?3-196 (also, respectively, in Transactions, Vol. LI, 1948, pp. 262-264 Vol. LU, 1949, pp. 117-120, and Vol: LIU, 1950, pp. 133-136), were distributed by the Dominion Coal Board and are still available on request. In this review, the first in the series in the field of combustion, development and trends during the period approximately from World War II to the present time are described and therefore the presentation is general. Later reviews will particularize developments in relation to the range of coals available in Canada.-ED. INTRODUCTION THE utilization of coal in heat and power producing equipment has become of paramount importance to the coal industry in maintaining stable and profitable markets. In the past, the chief concern was with mining, transportation, and overall supply problems, but modern conditions demand interest in and knowledge of all phases of the product, from coal in situ to its ultimate disappearance in the form of products of combustion. Even the last mentoined factor has caused complications, as is shown by current widespread activity in the field of smoke abatement

Jan 1, 1951

By M. H. Attia

The concept of sustainable development has been evolved into a working framework for sustainable manufacturing, in which the environmental requirements are introduced into product development at the design stage. This keynote paper is discussing a number of issues pertaining to the impact of manufacturing on the environment. The conflicting requirements of sustainable development, sustainable manufacturing (SM) and economical growth are presented in the light of successful case studies that were able to convert conflicts into opportunities. Integration of SM into the product life cycle is also presented. A number of concepts that are related to Ecoefficiency, e.g., inverse manufacturing, demanufacturing and re-manufacturing are also discussed. The paper underlines the fact that the positive impact of this new philosophy is equally applicable and beneficial to both; developed and developing countries. The paper concludes with an overview of Global trends in environmentally benign manufacturing (EBM); e.g., product-take back and emerging material and processing technologies. The state-of-the-art approach to Life Cycle Impact Assessment and integration of design for the environment DfE principles are demonstrated through some case study.

Jan 1, 2006

By M. Nzotta, L. Teng, S. Seetharaman, A. Chychko

The objective of the present work is to optimize the EAF practice towards Mo alloying with maximum retention of the alloying element in molten steel. During Mo additions, there were significant losses to the dust (ca 7 %) and to the slag phase (ca 2 %), which had serious economic and environmental impacts. The present work was aimed at designing a suitable Mo precursor, an alternative to ferromolybdenum, as the Mo source and a process sequence for optimal retention of Mo in the steel. The design of the Mo source should be in such a way that low cost raw materials such as MoO3 concentrate have to be used, stable during the addition so that the vapour phase losses as MoO3 are kept minimum and the dissolution of the precursor in molten steel is easy without loss to the slag phase. After thermodynamic considerations, three precursor materials were chosen, viz. CaMoO4, MgMoO4 and Fe2MoO4. Synthetic mixtures of the component oxides in each case as well as pure MoO3 were investigated by TGA and high temperature XRD in order to find out the temperature range in which the compounds were formed. Experiments were also conducted separately where the evolved gases were analyzed. All the three precursors were formed easily and the loss of MoO3 to the vapour phase was found to be extremely low. Addition of the oxide mixtures to steel melts were conducted in three different scales, viz. 16 g, 500 g and 3 tons (induction furnacle). Initial experiments showed that MgMoO4 was not suitable since the Mo yield in the steel melt was not very high. Fe2MoO4 was found to perform best, the Mo yield reaching 98 %. Further trials were conducted in the 65 ton Electric Arc Furnace (EAF) at Uddeholms AB in Hagfors. Mixtures of mill scale, MoO3 and carbon in suitable proportions were added in a pre-determined addition sequence. It was found that, in the actual practice, the Mo yield reached 99 %, equaling in performance the addition of ferromolybdenum. The process offers an effective use of cheaper raw materials and very high Mo yield avoiding a pre-treatment step like the production of ferromolybdenum. This is both cost effective and environmentally advantageous. The process has been patented and is being currently implemented at Uddeholms AB, Hagfors, Sweden.

Jan 1, 2011

By R. Filippone, Donald Leroux, Colin Hardie, G. Leichtle, Cesar Gomez, Jim A. Finch

"Bubble surface area flux (Sb) is the surface area of bubbles per unit time per unit cross-sectional area of flotation machine. The units are: (m2 bubble surface/s)/(m2 cell) or s -1. For bubbles of mean size db (m), s b = 6-Qg/A db where Qg is the gas rate (m3/s), and A the cell cross-section (m'). This parameter is now receiving wide attention as the possible key machine variable in flotation diagnosis and modelling. The concept is described and the potential use of sb is illustrated by work on flotation columns and mechanical cells. In column flotation of recycled paper, the dependence of ink recovery on s b was the same regardless of size of column or type of sparger. In mechanical cells, it has been established that the rate constant is related to Sb independent of impeller type.The use of s b is limited by the problem of measurement, primarily that of estimating db. A prototype probe designed to estimate db (and hence sb) based on conductivity measurements is described. Exploratory work with the probe in a mechanical cell suggests the promise of making estimation of s b routine.INTRODUCTIONFlotation is the result of interaction among variables associated with the feed particles, chemistry and the machine (flotation cell). Trying to isolate the effects of each aids in process diagnosis and is at the centre of attempts to model flotation. The machine variables that have been investigated include the air flow number, the power number and specific power (Harris, 1976). None have survived as the basis for predicting flotation response perhaps because they did not include directly the properties of the bubble swarm (or dispersion). Recently, Gorain (1 997) explored the relationship between the flotation rate constant and various ""gas dispersion"" parameters notably: superficial air rate (Jg = Qg/A, where Qg is the volumetric gas rate and A is cross-sectional area of cell), bubble size (db), gas holdup (Eg, i.e., the volumetric fraction of a cell occupied by gas) and bubble surface area flux (sb = 6.Jg/db). Of them all, Gorain et al. (1997) conclude that the latter, the surface area flux, correlated best with the flotation rate constant. This concept was adopted from column flotation where it was used to estimate, among other factors, the maximum amount of gas that could be injected (Finch and Dobby), 1990). Let's start by reviewing the concept. Following that some examples of where the concept has been applied will be described to illustrate the current interest and finally we will consider how to measure the surface area flux."

Jan 1, 1999

By D. A. Rhys, M. Sieb, M. A. Prefontaine, C. L. Swanson, S. R. Frostad, H. Q. Smit

"Gold-silver mineralization at Red Mountain (1992 resource of 2.5 million tonnes grading 12.8 g/t Au and 38.1 g/t Ag) occurs within several discrete zones within a folded sequence of Middle to Late Triassic Triassic sedimentary rocks, Early Jurassic volcaniclastic and pyroclastic rocks, and Early Jurassic intrusions. Three phases of Early Jurassic sills and stocks collectively comprise the Golds/ide intrusions: (1) irregular bodies of medium-grained hornblende monzodiorite (Hillside porphyry); (2) hornblende-biotite + quartz porphyritic monzodiorite to quartz monzodiorite (Golds/ide porphyry; U-Pb zircon ages of 197.1 + 1.9 Ma); and (3) biotite porphyritic hornblende monzodiorite sills (Biotite porphyry). Contact breccias and igneous breccia dikes are common features of the Golds/ide intrusions. Chemical similarities and equivalent ages of volcanic rocks and intrusions, and the presence of intrusive clasts in volcanic rocks suggest that the intrusions are feeders to overlying volcanic units.Hydrothermal alteration affects all pre-Tertiary rocks on Red Mountain, including all phases of the Golds/ide intrusions. Several shallow-dipping alteration zones are developed sequentially above a propylitic quartz stockwork/molybdenum zone. These include: (1) sericite-quartz-pyrite alteration (pyrite-dominant alteration); (2) chlorite-K-feldspar-sericite-titanite alteration with disseminated and vein pyrrhotite (pyrrhotite-dominant alteration); and (3) brown to black tourmaline veins and K-feldspar-pyrite-titanite-actinolite alteration. Anomalous gold(> 0.3 g/t) mineralization is developed at the transition from the pyrite to the pyrrhotite dominant alteration over a > 1 km2 area. Within this anomalous zone, high-grade (3 g/t to 20 g/t Au) gold-silver mineralization occurs in 5 m to 29 m thick, semi-tabular pyrite + pyrrhotite stockworks with intense sericitic alteration and surrounding disseminated sphalerite + pyrrhotite.Stratigraphic, spatial and geochronologic relations and alteration zoning indicate that mineralization formed in a subvolcanic environment at the top of the Golds/ide intrusions and at the base of the Early Jurassic volcanic pile. The Golds/ide porphyry is interpreted to be the mineralizing intrusion. The alteration zoning, molybdenum-copper mineralized quartz stockworks, extensive Ksilicate and tourmaline alteration, and the relationship with a hypabyssal porphyritic intrusion show similarities to many porphyry systems."

Jan 1, 1995

By J. E. Hawley, Y. Rimsaite, T. V. Lord

"IntroductionIN THE COURSE of. a spectrographic investigation of the platinum metal .content of various minerals in sulphide ores, the use of • fire-assay beads dissolved in gold-amalgam ( 1) was found suitable for the quantitative determination of palladium and platinum. Later work on platinum and bismuth-rich beads showed however, that these could not always be readily mixed uniformly in the amalgam. Accordingly another technique was sought which would allow the simultaneous determination of gold, silver, palladium, platinum, rhodium, and bismuth, the last .a common contaminant in fire-assay beads. The method evolved, which consists of dissolving fire-assay •beads in .lead, resembles in several respects the method of Scobie (2) in which silver was used. It has equally good sensitivity arid reproducibility, and allows the determination of silver as well as the other metals mentioned. The 'mutua1 standard' method of calculation (3a) is used to determine actual quantities present. This method has been applied to sulphide and arsenide minerals and •ores• of nickeliferous and non-nickelferous deposits• of both pre-and post Cambrian age, and, following a suggestion by Dr. G. S. Hume and the late Dr. H. V. Ellsworth, Geological Survey of Canada, has also been used for a peculiarly rich platiniferous uranium oxide ore from the Nicholson property, Lake Athakaska, Sask. More recently, the method has been .tested for the determination also of iridium and ruthenium and results indicate it may be applied, as• well to osmium."

Jan 1, 1953

By J. Keith Haddock

"Introduction The Luscar company, Forestburg Collieries Ltd., operates the Diplomat Mine located 14 km south of Forestburg, Alberta. Production is now at a declining rate from the 1 million tonnes achieved in 1978 as the reserves are being depleted. Three pits are operated at this prairie strip mine utilizing draglines and stripping shovels to uncover the coal. The coal is hauled to a tipple on site for shipment by rail or highway vehicles or is hauled directly to the adjacent Battle River Generating Station. Geology The mine is currently extracting the Battle River seam on the north side of the Battle River. This is the lower-most seam in the Horseshoe Canyon Formation and is the only one present in the area, the upper seams having been eroded by glaciation. The seam lies generally flat and varies from 2.0 to 5.0 metres thick. It lies under glacial till overburden varying in depth from 5.0 to 12.0 metres. The mineable coal extends from the side of the Battle River valley where it outcrops, to approximately 2.5 kilometres to the north. The mine is spread out over a distance of 8.0 kilometres in an east-west direction. Reserves and Coal Quality After over 30 years of mining at Diplomat, there are now less than 1 million tonnes of mineable reserves remaining on the property. With the commencement of coal production from the Paintearth Mine in 1981, supply to the Battle River Generating Station, formerly Diplomat's biggest customer, is being transferred to Paintearth. Rail shipments and domestic supply will continue until reserves are depleted. The coal has the following specifications:"

Jan 1, 1985

By H. Ranjbar

The Darrehzar porphyry Cu deposit is situated in the Urumieh-Dokhtar magmatic suite of Central Iran. The REE and trace element data suggest that the deposit lies within a continental margin setting. Phyllic and propylitic alteration are pervasive in the area but potassic and argillicalteration are not readily recognized on the surface. This is possibly the result of super gene weathering of the surface rocks or because of an intense phyllic overprint. Poor soil development and abundant outcrop make the area suitable for a case study of lithogeochemical exploration technique for Cu deposits. A total of 262 rock samples was collected over the area and analyzed for 15 elements. The geochemical data cor-relate with the mineralogical composition of the rocks with the phyllic zone being marked by high-er concentrations of Si, Al, K, and by a high sericitization index while Ca, Mg, Sr, total Fe and Mn are more abundant in the propylitic zone. The lithogeochemical study indicates a metal zonation from a Cu + Mo-rich core to a Zn + Pb ± Ag-rich outer zone. Principal component analysis is useful for separating element associations, which in turn reflect the alteration halos. Principal components 1 and 2 depict alteration zoning, where-as 3 shows an association of Cu and Mo, that roughly defines the mineralized area.

Jan 1, 1997