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By J. McCreedy

This paper reviews new methods of exploration for metals and new techniques of mining the deposits and extracting the metals from their ores. Examples of mining innovations are taken from Inco's Thompson Operation. The importance of presenting a favorable image of the industry to college students and young people deciding on a career is stressed.

Jan 1, 1971

By Fred G. Hewett

Cassiar Mine in northern British Columbia began development in 1952. The deposir is found on rhe west limb of rhe McDame Synclinorium in a Mississippian serpentinite body. The serpenltntte, one of the McDame l ntrusives, imrudes Sylvester Group . rocks, which comprise a Lare Devonian to Early M1ss1ss1pptan eugeosync/inal sequence of argillites, quarrzires and volcanics. The foorwall conracr berween Sylvester Group rocks and rhe serpenrinire is a marked zone of broken and incomperent argillite and graphitic schist. The less marked hang- 111gwall contacr 1s a band of indurated argillite. The JurassicCretaceous emplacemenr of the Cassiar Graniric Barholilh is responsible for mosr of the numerous )aims, faulrs and shear zones found in the serpentinite body. Faulting occurred borh before and after asbestos formation. Asbestos is mined from an open pit ar rhe rate of 4,535 ronnes daily. It passes from the pir along a rramline to the mill, where it is concen/rared into nine direcr milling grades. Packaged fibres travel ro over 40 counrries around rhe world for use in the texrile, cemenr and other industries.

Jan 1, 1984

By P. C. Patnaik

Performance of industrial gas turbine engines in terms of power output, reduced cooling and efficiency have been continuously increasing in parallel with aero gas turbines due to the advances made in the development of new materials, protective thermal barrier coatings (TBCs) and the advanced diagnostics to monitor service induced problems such as hot corrosion, thermal and thermo-mechanical fatigue and other operational issues, Environmental attack (hot corrosion or high temperature oxidation) is a common degradation mode in the hot section of the gas turbine, Hot corrosion occurs when Na or K bearing compounds in the environment or in the fuel combine with other contaminants such as S and Pb or V to form corrosive sulphates or vanadates thus attacking the protective oxide on the turbine airfoil, These problems pose far more threat to new turbine engine materials such as directional solidified, single crystals and ceramic matrix composites (CMCs). The CMCs due to their increased temperature capability, when used in the combustion chamber, are likely to reduce the peak temperatures attained during combustion and therefore provide the benefits of reduced emissions of oxides of C and N, These issues will be reviewed critically and their impact will be assessed on gas turbine lives. With respect to alternate fuels, past experience has shown that utilization of residual oils and coal derived fuels in gas turbines have resulted in complex deposition and corrosion processes, In recent years biomass derived alternate fuels have been used either through a gasification cycle or through direct firing of the biomass derived liquid fuel with a view to reduce Green House Gases (GHGs) and improve the climatic conditions. In both cases, the resulting high temperature corrosion processes (in the presence of alkaloids in the fuel) are also very complex, leading to premature removal of hot section components, Technology solutions mitigating these fundamental problems will be reviewed and solutions presented.

Jan 1, 2005

By Sadough vanini Ali

Charpy impact energy of functionally graded steels produced by electroslag remelting in crack divider configuration has been modeled in various strain rates. It has been well known that majority of materials indicate different behaviors under different strain rates and temperatures. Therefore, modifying the elastic-plastic model considering the effects of strain rates and temperature gives us an acceptable prediction of these composites behaviors in impact test. In this investigation, graded steel was divided in to several layers in which the layers have the same strains under the impact. Constitutive equation describing the flow stress variations as a function of strain rates and temperatures, have been used to express the stressstrain behavior of layers. The parameter values of constitutive equation determined for all the layers via using the boundary conditions based on composite graded behaviors which were the characterized ferrite, austenite, bainite and martensitte phases. Consequently by applying the rule of phase mixtures and ascribing the impact energy of each layer to the area of stress-strain curve of the same layer, the whole impact energy of composite is the sum of layers impact energy with considering the layers volume fraction.

Oct 1, 2011

By J. Petit, P. Girard, A-M. Gilbert, D. Faucher

L&apos;annee 2000 a été une année stratégique et significative pour l&apos; Aluminerie de Bécancour dans la réduction des gaz a effets de serre. L&apos; équipe s&apos; etait donne comme defi un jour d&apos;arriver a l&apos;objectif de zero effet d&apos;anode dans les sa11es de cuve (720 cuves au total). Le cha11enge s&apos;averait tres ambitieux car la fa<;on d&apos;alimenter une cuve d&apos;electrolyse pour obtenir son maximum de rendement faraday est de travailler le plus pres possible de l&apos;effet d&apos;anode pour eviter l&apos;embourbement de ce11es-ci. Ceci signifie que techniquement nous a11ons en moyenne, quotidiennement, 12500 fois pres de l&apos;effet d&apos;anode sur !&apos;ensemble de nos 720 cuves qui produisent aujourd&apos;hui environ 405 000 tonnes d&apos;aluminium liquide annuellement. Des 695 kg equivalent en C02 par tonne d&apos;aluminium produite en moyenne annue11ement, de 1990 a 2000, nous en sommes rendus ace jour a environ 35 kg equivalent en C02 par tonne produite. Nous sommes pres d&apos; atteindre notre objectif mais les demiers gains sont plus difficiles a atteindre. Les strategies d&apos;automatisme et d&apos;informatique, incluant l&apos;aspect de !&apos;implication humaine sur les bonnes pratiques de travail sur les cuves d&apos;electrolyse, sont les cles de ces resultats.

Jan 1, 2006

By Serge Perreault

Le cuivre est un métal fascinant qui joue un rôle essentiel dans le développement des différentes civilisations depuis 7000 ans. Le cuivre est aussi un métal polyvalent et essentiel qui est très présent dans notre vie quotidienne. L’un des premiers métaux utilisés par les humains, il est un élément chimique qui se trouve à l’état natif, ce qui est rare pour les métaux. Il apparaît principalement dans des minéraux, notamment sous forme de sulfures, en raison de son caractère chalcophile (c’est-à-dire son attraction pour l’élément soufre). Le cuivre se trouve dans la croûte terrestre sous forme de minéraux de cuivre, tels que dans les sulfures dont la chalcopyrite, la bornite, la covellite et la chalcocite. Il est également présent sous sa forme native ou dans des minéraux oxydés comme la cuprite et dans des carbonates hydratés, comme la malachite et l’azurite. La formation de gisements de minerai de cuivre implique des processus géologiques complexes, notamment l’activité hydrothermale, les intrusions magmatiques et l’altération des roches. Les gisements de minerai de cuivre se trouvent dans divers types d’environnements géologiques, dont les gisements porphyriques, les gisements de cuivre encaissés dans des roches sédimentaires, les gisements de type skarn, les gisements de sulfures massifs volcanogènes, les gisements magmatiques de type nickel-cuivre, les gisements de cuivre oxydé, et d’autres [1].

May 2, 2024

By N. Bartie

Realising the circular economy (CE) is faced with some significant challenges. Process metallurgy and its infrastructure play key roles at the heart of making the CE work. Therefore, the enabling role of process metallurgy within the CE will be central to the discussion in this paper, touching among others on product and system design as well as the key metallurgical and other process fundamentals that need to be investigated and understood to make the CE a reality. The central role of materials and its processing will be discussed in an integrated circular cities perspective. A key focus will be a discussion on designing a resilient “Smart Materials Grid” using and innovating metallurgical process engineering tools, which will manage the flows through Sustainable Circular Cities. The discussion will be using copper as leitmotiv of the discussion i.e. from copper ore, to metal, to complex products, recycling, product design and simulation and its impact. INTRODUCTION The transformation of our economies from linear to circular models in which waste materials become resources is the focus of the Circular Economy (CE) paradigm. Its important intentions: to take control of the damage we have been doing to the planet to ensure its livability and the welfare of future generations. This can only be achieved through careful utilisation of human, natural and economic resources. The concept is derived from several others (Beaulieu et al., 2015), of which Cradle-to-Cradle, Extended Producer Responsibility (EPR), Industrial Ecology, and Life Cycle Thinking are just a few. Other relevant concepts include resource efficiency (RE), design-for-recycling (DfR), and various others discussed by Blomsma and Brennan (2017) and Homrich et al. (2018), as well as various R-hierarchies e.g. Reduce, Reuse, Recycle (3R). However, does society comprehend these concepts, the actors and actions that influence them and how they interact? Do we know the limits of CE? Does society understand the key role of Copper and other metals to rendering the CE operable? True life cycle and systems thinking, focussed on simulation-based, process and metallurgical design are required to answer these questions. Lieder and Rashid (2016) identify nine widely-varying fields that study the concept ranging from sustainability sciences and engineering to economics, business, law, and social sciences. Overlap between questions addressed highlights the need for interdisciplinary collaboration (Nanz et al., 2017) in the assessment of the current status, and further steps needed to transform to CE. This doesn’t apply just in academia, but also in industry where concrete implementation of CE needs to occur at multiple levels, thus necessitating cooperation between government, civil society and other stakeholders (Beaulieu et al., 2015).

Jan 1, 2019

By Elisabeth Kolar, Rik Catthoor, Frederik H. Kriel, Rossen Sedev, Gareth Hatch, Army Research Laboratory, Craig Priest, Scott Middlemas

"This paper reports solvent extraction of rare earth elements (REEs) carried out using a microfluidic device and considers the REE loading limit of the organic phase under laminar flow. The microfluidic device contacts aqueous and organic phase streams for a precisely defined contact time (subsecond resolution) and then separates them for offline analysis. Experiments are reported examining the effect of contact time on extraction. We focus on three REEs: one ‘light’ (Nd), one ‘mid’ (Dy), and one ‘heavy’ (Yb) REE, which are extracted using Cyanex® 572. It appears that loading limits may be locally exceeded in the organic phase near to the liquid-liquid interface, where third phase deposits are observed. Third phase formation was also observed close to the liquid-liquid interface in two-dimensional confinement, showing similar third phase adsorption on glass plates. It is also shown that, under microfluidic flow, a typical first ‘split’ between heavy REEs and light REEs can be carried out without exceeding loading limits.INTRODUCTIONMicrofluidic solvent extraction has emerged as a useful tool for studying extraction of metals in a mineral processing context (Ciceri, Mason, Harvie, Perera, & Stevens, 2013; Ciceri, Perera, & Stevens, 2011; Kriel et al., 2015; Mason, Ciceri, Harvie, Perera, & Stevens, 2013; Priest, Zhou, Klink, Sedev, & Ralston, 2012; Priest et al., 2011). The main advantages are the extremely well-defined and tunable flow behaviour, large surface-to-volume ratios, short contact times, and minimisation of sample and reagent amounts. Two main flow configurations have been studied to date: droplet-based and co-flowing streambased extraction. In the former, droplets are formed at a microchannel junction (usually a T-junction or flow-focusing junction) and flow downstream as plugs or ‘free’ droplets. In our case, stream-based extraction, the chip is a plate (often glass) with embedded microchannels (i.e. with cross-sections of tens of micrometres) that carry the aqueous and organic phases in contact without forming droplets. Thus, these chips play the role of a mixer in a conventional mixer-settler and phase separation takes place by branching the streams or collection in a vessel at the chip outlet. Stream-based extraction requires stable streams that are usually supported by a particular channel geometry (e.g. guide structure or small ‘pillars’) or surface chemistry, and flow parallel bounded by the liquid-liquid interface(Aota, Nonaka, Hibara, & Kitamori, 2006; Hibara et al., 2005; Hibara et al., 2002). Phases are disengaged downstream at a Y-junction, which is a qualitative difference between microfluidic and bulk extractions."

Jan 1, 2016

By David G. Dixon, Ahmad Ghahremaninezhad, Edouard Asselin

"Atmospheric leaching of chalcopyrite in sulfuric acid solutions is a slow process due to the mineral’s passivation. We have investigated the nature of the passive film in this work. Electrochemical reduction and oxidation of chalcopyrite over the potential range of -0.5 to 1.2 VSHE were investigated in 0.5 M sulfuric acid solution (pH 0.3) at 25 ºC by multicyclic voltammetry and open circuit potential measurement. The influence of scan limits on the evolution of current peaks was studied with both stationary and rotating electrodes. It was observed that the anodic oxidation of chalcopyrite begins at potentials above 0.6 VSHE, most likely by preferential dissolution of iron atoms over copper atoms. The selective electro-dissolution process results in formation of a metal-deficient sulfide passive film (i.e. Cu1- xFe1-yS2, y > x). The passive film dissolves at 0.9 VSHE. Elemental sulfur is one of the products of chalcopyrite dissolution above 1.0 VSHE. Cathodic reactions within the potential region of 0.1 to 0.6 VSHE and anodic reactions at potentials lower that 0.5 VSHE are associated with at least one soluble species from solution. The soluble species involved in the cathodic reactions are likely ferric and cupric, while the soluble species involved in the anodic reactions is likely H2Saq."

Jan 1, 2014

By J. C. Hampton, L. A. Matzar, C. R. Gamwell

In geomechanics, conducting uniaxial or triaxial compression tests require samples to be prepared to a certain length-to-diameter ratio. This ratio is typically defined as 2:1 (length to diameter) and is accepted as a common standard for all materials on which mechanical properties testing is performed. Variations in sample length can cause changes in measured strength properties across multiple material types, such as cement, rock, or soil. Within the oil and gas industry, it is not uncommon to receive samples for technical services work that are slightly under or exactly the length requirement before surface grinding and sample preparation. Many of these samples are discarded from uniaxial and triaxial compression tests and used in another manner; therefore, it is necessary to study the length-to-diameter ratio in efforts to understand the limits and validity of testing samples that are slightly out of the 2:1 ratio. This paper discusses uniaxial compression tests performed using Berea sandstone and a standard cement mixture of 2.54-cm diameter to study changes in rock strength and properties. Compressive strength for each lengthto- diameter ratio over a range of 0.5:1 to 2.2:1 was measured. The investigation was extended to study near-end effects, where the sample length is near, but not exactly twice the diameter. It was discovered that the cement samples conformed reasonably well to the suggested ASTM correction factors. The sandstone did not conform to the correction factors and further analysis is required to develop a correction factor unique to the material. Near end effects, in both the cement and Berea, were found to increase compressive strengths, especially when the L/D of the samples was increased slightly over a 2:1 L/D.

Jan 1, 2015

By J. A. Haskin

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

Jan 1, 1935

By I. Raheb, M. Y. Debili

"A set of Al-Co binary alloys (with respectively in weight percent 10%, 20%, 30%, 40%, 50% and 60% Co) have been studied by X-ray diffraction at the as compacted state. The structural evolution according to cobalt addition shows special features as the apparition of fcc cobalt and hcp cobalt beside aluminium in some cobalt compositions of the Al-Co mixtures using only cold compaction without sintering at high temperature. Figure 1 Cobalt is not a common alloying element in aluminium because its solubility is very low [1]. According to the pressure-temperature phase diagram, Co is known to exist in two allotropic forms: a low-temperature hcp phase and a high-temperature fcc phase [2-3]. At room temperature, Co is stable in the hcp form but it transforms to the fcc form when it is heated to above the transition temperature 695K. Powder aluminium and cobalt (99.999 %) were used in the proportions defined according to the required compositions. The total mass of the samples to be elaborated was between 8 g and 10 g. Cold compaction of mixed powder (Al-Co) under an uniaxial load of 10 MPa has been achieved to obtain a dense product (60%)."

Jan 1, 2015

By I. C. Edwards, D. C. Smith

THE milling plant of Bicroft Uranium Mines Limited at Ban-croft, Ontario, was one of the first in Canada to employ ion excl1ange for the selecti1•e recovery of uranium from acid leach liquors. The ion ex-change circuit started operating early in November, 1956, and by June 1 I959, had handled more than two million tons of pregnant solution containing I,830,000 pounds of U3Os. Each column had been saturated and eluted about 430 times. The ion exchange columns are the conventional fixed bed type. Uranium is eluted from the resin with a sodium chloride-sulphuric acid solution and is precipitated continuous-ly with magnesia. After filtering and drying, the precipitate, or "yellow cake," is packaged in drums for shipment to the refinery.

Jan 1, 1962

By Abhilash

Uranium is conventionally extracted using a process that employs strong acid (H2SO4) and an oxidant (MnO2) as leaching agents. This method often creates environmental problems, requires large amounts of energy, and involves a complex operational plant. It is not, however, economically attractive to extract uranium from low-grade ores by chemical leaching. Because the content of U3O8 in the Indian ore is usually below 0.1% by weight, it is necessary to develop an alternative process to enable the efficient and economic recovery of uranium. Uranium ore from the Narwapahar mines, UCIL is a type of vein deposit found in India, which accounts for ~54% in India. The ore (0.047% U3O8), though of Singhbhum area, possess exceptionally different mineralogy due to presence of some refractory minerals and richness of apatite (5%) resulting in a maximum 78% recovery through conventional processing at UCIL, with a very high consumption of sulfuric acid and pyrolusite, besides possible loss of uranium as uranium phosphate. To avoid usage of environmentally non-benign oxidants, remediation of influence of phosphates, and improve the overall process output of uranium; an alternate extraction technology using microbial isolate(s) is worthwhile exploring and the same is presented in the paper. The microbial isolate enriched with Acidithiobacillus ferrooxidans grown from source mine water was employed for bio-leaching of uranium while varying pH, pulp density (PD), particle size, etc. On varying pH at 35oC using 20%(w/v) PD and <75µm particle size, 83.5% and 78% uranium bio-recovery were observed at 1.7 and 2.0 pH in 40 days against maximum recovery of 46% and 41% metal in control experiments respectively. Whereas, it was observed that grinding of ore to finer size actually helped dissolution of uranium. Finer size particles (<45µm) gave a maximum biorecovery of 93% in 40days at 10%(w/v) PD, 1.7 pH and 35oC. The bio-recovery of uranium fell down from 93% to 82.73% and 60% on increasing the pulp density from 10% to 20% and 30% respectively for particles of <45µm size. The higher uranium dissolution during bioleaching at 1.7pH can be correlated with increase in redox potential from 433 mV to 664mV in 40 days.

Aug 1, 2010

By V. Songmene, R. Khettabi, J. Masounave, R. D. Njoya

L&apos;augmentation régulière des règlements environnementaux et de la sécurité au travail deviennent de plus en plus strictes. L&apos;usinage fait partie des opérations industrielles qui peuvent causer des problèmes de santé au travail et sur l&apos;environnement. La plupart des particules de poussières produites pendant toutes les opérations d&apos;usinage à sec ou lubrifie causent des nuisances environnementales graves. Le travail propose étudie l’influence des paramètres de coupe, des alliages et des états des matériaux sur la formation des copeaux et sur la génération de poussière lors de l&apos;usinage à sec. Deux modes d&apos;usinage (le fraisage et le perçage) sont abordés. Une loi reliant la ténacité des matériaux aux émissions de poussières est proposée. Les effets des matériaux et de leurs conditions, ainsi que des procédés d&apos;usinage sur la génération des poussières ont été mis en évidence. Des mécanismes de formation de poussières sont identifiés et reliés à la formation des copeaux.

Jan 1, 2006

By J. Donnelly, A. V. Deev

Substitution of coal and coke by renewable carbon (charcoal) is a low-risk and low-capital path to 50% or more reduction in net CO2 emissions by the steel industry. However, the high cost of charcoal and its low availability in most countries are barriers for the implementation of this approach. Development of an efficient wood carbonisation technology (slow pyrolysis) capable of producing large-volumes of charcoal from low-cost wood feed (e.g. wood wastes or forest residues) is an essential step towards the use of renewable carbon by the iron and steel industry. This paper provides a summary of the progress made over several years of R&D covering: (1) development and piloting of a new energy efficient slow pyrolysis process for production of charcoal from woody biomass at a competitive cost to the PCI coal, (2) techno-economic evaluation of the process. The main feature of the process is that the material undergoing pyrolysis is heated spontaneously without the supply of heat or air to the reactor. This makes it possible to carbonize large volumes of small-sized wood (e.g. wastes and residues) in a single reactor unit and capture high calorific value pyrolysis by-products

Jan 1, 2015

By C. M. Trigg

"PEC uranium deposit, 100 km southwest of Coppermine, was discovered by diamond drilling in 1976 following ground and airborne geophysical surveys, geological mapping, geochemical surveys and boulder prospecting that were initiated as the result of the discovery of uraniferous sandstone outcrops in 1969 by geologists of Aquitaine Company of Canada Ltd.The deposit is within gently northeasterly dipping medium to coarse-grained Unit 11 quartzitic sandstone of Neohelikian Dismal Lakes Group. The deposit is from 10 m to 70 m above the base of the sandstone which, beneath the deposit, non-conformably overlies weathered and altered Aphebian granite of Great Bear Batholith or unconformably overlies rubble breccia, conglomerate and medium-grained Unit 8 sandstone of Paleohelikian Hornby Bay Group.A northeasterly trending, 500 m wide graben, bounded by the steeply dipping northeasterly striking Imperial and Aquitaine faults, contains the deposit which is 1.1 km long by up to 340 m wide. The deposit overlies a post-Hornby Bay Group, pre-Dismal Lakes Group topographic high. Uranium principally occurs as stratabound, often peneconcordant bands; a lesser amount of uranium is fracture controlled.Stratabound uranium exists in gently easterly dipping, subparallel bands ranging in thickness from 1.5 m to 6.0 m. Pitchblende, coffinite and sooty black uranium oxides occur as interstitial disseminations and grain coatings subparallel to bedding; they also replace pyrite and form narrow veinlets.Small amounts of torbernite, carnotite and cuprosklodowskite coat pitchblende and are disseminated within mineralized bands. Pyrite, marcasite, chalcopyrite, chalcocite, cove/lite, digenite, azurite, malachite, arsenopyrite, glaucodot, niccolite, bravoite (? ), goethite, hematite and magnetite as well as quartz, barite, calcite, biotite, chlorite and clay minerals exist within the mineralized bands. Uranium grades of 0.1 % to 0.3 % U3O8 over thicknesses of 1 m to 2 m are typical.A steeply dipping fracture zone near the Imperial fault contains sooty black uranium oxides, torbernite, carnotite and cuprosklowdowskite as well as sulphides, cobalt arsenides, quartz and carbonate. The zone may reach 70 m long; its true width is about 1.9 m. Uranium grades range up to 5.18% up, over0.9m.Pitchblende and coffinite from PEC deposit have been dated at 1.08 ± .10 Ga with possible remobilization at .45 Ga. The deposit contains an inferred 3,150 tonnes of U3O8."

Jan 1, 1986

By A. W. Johnston, R. E. Barrett

"The Central Patricia mine is in the greenstone belt north of lake Sc. Joseph in northwestern Ontario. It is 90 miles north of Allanwater on the Canadian National railway and 220 miles east of the Manitoba boundary. The unusual feature of the ore of this mine is that the gold does not occur in quartz but in sulphide minerals filling fractures in iron formation.AREAL GEOLOGYThe rocks of the area in which the mine occurs belong to the Early Precambrian. They consist · of andesite lavas and tuff interbedded with greywacke-like sediments and iron formation . A siliceous phase of the sediments lying north and south of the greywacke enclosing the ore-bearing iron formation in places resembles a sheared and sericitized quartz porphyry. This is shown in the legend of Fig. 1 as quartz porphyry and quartzite, but it is possible that the quartz porphyry-like phase is sediment. A northwest- striking dyke of diabase crosses the property 3,000 feet east of the shaft ( Fig. 1).IRON FORMATIONAlthough there are numerous bands of iron formation in the v1cm1ty of the mine, ore has been found to date in only one main and two lesser zones. The iron formation bands range in width from a few inches to 60 feet, and are interrupted along their strike by gaps that are parallel and rake to the east at about 65°. The iron formation is definitely banded and laminated."

Jan 1, 1954

By Donald F. MacDonald

THE cement plant nearest to Nova Scotia is not far from Montreal. Cement is a heavy product which, because of its relatively low value, cannot stand a high freight charge without unduly enhancing its cost. This is one reason why cement costs are high in Nova Scotia. The regular retail price per bag (8772 lb.) in Antigonish is 85 cents, which would be $3.40 per Canadian barrel of 350 pounds, or $3.65 per American barrel of 376 pounds.It is said that the lowest wholesale price in Halifax is 65 cents per sack, which would be $2.60 per Canadian barrel or about $2.80 per American barrel. According to U.S. Bureau of Mines statistics, the average factory price for cement in 1937 was $1.48 per American barrel, which is practically the same as the value per barrel indicated in Dominion statistics for the Canadian output during that year. The difference between $3.40 and $1.48 is $1.92. It is evident that the average user of cement in the Mari-times pays a stiff premium because Maritime cement raw materials have not been developed. Rock-wool, the manufacture of which is rapidly increasing in Ontario and the United States, is much needed for building insulation in the cold climate of Nova Scotia.

Jan 1, 1939

By L. Haavanlammi

The Outokumpu HydroCopper® process is a chloride based atmospheric leaching process alternative that can treat a variety of different concentrates. Chalcopyrite and other copper sulfides can effectively be leached under atmospheric pressure in strong, aggressive chloride solution using copper (II) ions as oxidant. Impurities are removed from the solution as carbonates and ion exchange. Copper is precipitated from the purified pregnant leach solution as copper (I) oxide, which is filtered and reduced by hydrogen gas to metallic copper powder, which is melted and cast into copper product. Sodium chloride solution from copper (I) oxide precipitation is decomposed in a chloralkali electrolyser, to products of which are circulated back to the process. The process has been designed for copper concentrates and is a fast and economical way to produce copper wire rod directly from concentrate. The process can efficiently handle impurities like arsenic and mercury, which can be harmful in the pyrometallurgical processes. The process has been tested in the laboratory and 1 ton/day demonstration plant scale and it has been proven to be commercially viable. The process has been designed to meet the strictest directives for emissions. Other environmental factors are carefully considered to obtain the highest possible eco-efficiency.

Jan 1, 2007