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By B P. Scott

Podsol soil horizons developed on Pleistocene glacial sediments overlying the Coronation Mine orebody were analyzed for copper and zinc spectro-photometrically, using biquinoline-isoamyl alcohol and dithizone carbon tetrachloride reagents. Copper and zinc are concentrated in the A. and C horizons, whereas the A1, A2 and B horizons are leached. Of economic significance is the fact that the C horizon contains a copper anomaly, in excess of 100 times back-ground, directly over the orebody. Due to the erratic distribution of high copper concentrations in the Ao horizon with respect to the orebody, that horizon is not considered as a reliable prospecting datum. U NDER certain conditions, metallic ore deposits are accompanied by primary halos of trace elements in unweathered rock surrounding the orebodies or by secondary halos in weathered rock, alluvium, soil, or vegetation above or near the mineralized zones. Where such halos occur, chemical analysis, as applied to the detection of trace elements, is a valuable prospecting aid, permitting the detection of mineralization of possible economic value.

Jan 1, 1965

By Seunghoon Lee

The increase in the number of higher and larger buildings is expected to require the buildings' outer wall maintenance process, which includes cleaning, painting and monitoring, still depends on manpower. In this study, we proposed the robotic building maintenance system and aimed to reduce the jerk effect through the motion control of the system, improve the performance of the maintenance task, and ensure longer life and safety by improving the stability of the building structure and robot system. Through the results of the motion control and field-test with the proposed system, in specific, horizontal sliding module (HSM) showed that the jerk oriented by impact force was significantly reduced, feasibility of the proposed method was verified, and the robotic challenges were explored.

Aug 1, 2013

By N. Saracoglu, J. P. Golightly, R. H. Wallis, J. J. Brummer

"In January 1974, the Minerals Division of Canadian Occidental Petroleum Ltd. made the strategic decision to add uranium to its active exploration commodities and through compilation studies selected northern Saskatchewan as the most attractive and cost-effective exploration area in Canada. In August 1974, 100 sq. miles were staked adjacent to Gulf Minerals' Rabbit Lake deposit and east of the Esso Minerals Midwest boulder train. Initial exploration was based on geologic models of the Rabbit Lake deposit.In the summer of 1975, surface surveys delineated radon anomalies which were drilled that winter and found to overlie anomalous concentrations of uranium in the regolith which forms the upper unit of the crystalline basement. Within the crystalline basement, one hole intersected graphite and pyrite with anomalous nickel-cobalt-arsenic. Geochemical and radiometric surveys followed in the summer of 1976. Drilling in the winter of 1977 intersected several zones of graphite and also anomalous, but uneconomic, uranium abundances. Also in 1977, Dahlkamp and Tan (1977) described the coincidence of graphite and uranium at Key Lake and ground EM surveys on CanadianOxy claims detected graphite conductors beneath 250 ft of Athabasca sandstone. Inco Limited joined the project in April 1977 as a 50% partner. The project area was then surveyed using the airborne INPUT EM method, which detected 84 miles of conductors, with associated graphitic metasediments. On the ground these were located with MaxMin surveys, and follow-up drilling located the ""Tent"" Lake uranium zone.In 1978, the Midwest and Dawn Lake discoveries were announced, 7 miles and 2 miles west of the Joint Venture (J.V.) claims; and, in part for this reason, the 1979 winter drilling was concentrated on the deeper west side of the property. Exploration hole 102-79 intersected altered and uraniferous rocks, but stepout holes were barren. Drill hole 153-79 tested an under-snow three-station radon anomaly east of hole 102-79 and intersected 33 feet of 7.51 % U3O8, confirming the disco very of the McClean North zone. The geophysical grid of the McClean North conductor system was extended and detailed a strong, continous conductor to the south, called McClean South. This was drilled in January 1980and hole 1004-80intersected 22 feet of 2.95% U3O8."

Jan 1, 1983

By Erwin L. Zodrow

THE AUTHORS welcome this timely opportunity to comment o n a paper by MacLean and Merner (" Room-and- Pillar Mining at the Prince Mine of the Cape Breton Development Corporation " , ClM Bulletin , June 1978, pp. 59-62) concerning the rock falls and their relation to "a change in the strata". First, however, it is proper to express our gratitude to the Cape Breton Development Corporation, and in particular to A. R. MacLean, for making it possible for us at the College of Cape Breton to start two new collections. The first of these is a fossil plant reference collection from the Sydney Coalfield, Cape Breton (Upper Carboniferous period) , and the second is a documentation of the role o f pyrite in the formation of hydrated sulphates (samples from No. 26 Colliery, 1-B Mine, and the Prince Mine at Point Aconi). Conditions of sedimentation in the deltaic-type basin of the Upper Carboniferous time in the Point Aconi area were such that on the (coal) swamp, now represented by the Stubbart (or Hub) seam , (a) clays of varying thickness and extent were deposited , (b) biogenetic sulphur was introduced and (c) flora were buried. These are essentially the culprit s that make rock falls possible and at the same time predictable over large areas (in the present mine). The clays lithified to become shale, and biogenetic sulphur combined with iron to become pyrite (marcasite?), which exists as nodules and in fine-grained layers.

Jan 1, 1978

By C. J. Mwenifumbo

Preservation of groundwater quality is a major environmental concern. The disposal of hazardous material from urban waste dumps, milling wastes in tailings ponds, and industrial wastes in injection wells may contaminate potential sources of potable groundwater. The containment or migration of contaminants in the subsurface depends on bedrock characteristics and type of overlying sediments. Fractured bedrock and permeable sediments that may provide pathways for the transport of potentially harmful contaminants should be avoided when selecting a disposal site. The role of borehole geophysics in hazardous waste-site investigations is reviewed in three categories: (I) site selection; (2) determination of the extent of contamination at existing sites; and (3) long-term monitoring of migration of contaminants. In the first category, borehole geophysical techniques developed for lithology and fracture identification, and for porosity determination, provide some of the necessary information for understanding the subsurface hydrogeology. Lithological information can be obtained from gamma-ray, electrical resistivity, induction, magnetic susceptibility, and sometimes induced polarization logs; fracture detection and characterization can be accomplished with the use of caliper, density, resistivity, temperature, and acoustic televiewer logs. Estimates of porosity are derived primarily from neutron-neutron, resistivity, density, and soniclogs. Borehole geophysical techniques used in water quality determinations include self-potential, fluid resistivity, Eh (redox potentials) and pH measurements, and these can be used to map the extent of contamination at an existing waste site. Cross borehole and borehole-to-surface electrical methods can also be used in this application. Long-term monitoring of contaminant migration in boreholes can be accomplished with techniques that respond to changes in electrical conductivity, temperature and fluid chemistry caused by the presence of contaminants.

Jan 1, 1993

By G. S. Dobby, J. A. Finch

"A significant development in froth flotation technology has been the emerging industrial acceptance of column flotation during the past few years. Flotation columns are being employed now in several Canadian base metal concentrators and they are being considered f or a wide range of flotation applications throughout North and South America. Since the operating principles of a column differ markedly from those of conventional flotation machines, and have been poorly understood, scale-up of columns has been difficult. This paper describes a methodology f or translating laboratory column data to industrial operation.The scale-up model utilizes kin etic data that is obtained from a series of laboratory column experiments; the laboratory column can be as short as 2 m. For modelling purposes the column is considered to consist of two zones: the collection zone, where particle recovery occurs, and the cleaning zone, a packed bubble bed generated by downward flowing wash water. Mixing conditions in the collection zone have been characterized using the results of tracer experiments on plant columns at Mines Gaspe. The same experiments demonstrated the nearly complete suppression of entrained gangue minerals that is attained in the cleaning zone. The model explicitly accounts for both the collection zone and cleaning zone recoveries and allows for the effects of bubble overloading. Results of column scale-up experiments at Gibraltar Mines are presented."

Jan 1, 1986

By H. McIntire, R. Preston, D. Roberts

"Repeated 3D terrestrial digital photogrammetric surveys were conducted on hard rock mine pillars to characterize damage during secondary mining. Damage was quantified by measuring Depth of Failure, DOF, from spalling material and crack intensity, D21. These damage values were then correlated to visually assessed Pillar Damage Ratings and numerically estimated pillar loads. Measured damage, particularly Depth of Failure, correlated well with Pillar Damage Ratings. Numerical predicted pillar stress vs. damage exhibited the expected trend with shorter pillars being stronger. High resolution photographs and 3D models were also used to characterize damage mechanisms, which were found to be structurally constrained. INTRODUCTIONThe Doe Run companies Southeast Missouri Operations consists of six room and pillar lead mines (Brushy Creek, No. 29, Casteel, Buick, Fletcher and, Sweetwater) (The Doe Run Company, 2014). The mines are hosted in the Carbonates and Shales of the Viburnum trend with mining depths varying from 180 to 300 m. Pillars are commonly cut square with widths varying from 7 to 9 m and heights generally between 5 and 18 m, resulting in extraction ratios between 80 and 85% (Roberts et al., 1999). Figure 1 presents an idealized stratigraphic section through the Viburnum trend and Figure 2 shows a plan view of the five areas spanning the three mines included in this study."

Jan 1, 2015

By J. F. Wright

INTRODUCTION Eighteen years ago about half a dozen experienced prospectors moved from northern Ontario to northwest Manitoba to prospect 'greenstone' areas shown on geological maps of .parts of northern Manitoba prepared by J. B. Tyrrell, D. B. Dowling, and Wm. Mclnnes. Gold-bearing quartz was soon discovered by these men in this new field, and in succeeding years many more prospectors entered the district. A number of the pioneers are still prospecting, and since 1913 mineral deposits have been discovered each year in widely separated areas of the large district extending 150 miles eastward from the 102nd meridian and 60 miles north of latitude 54°30'. The majority of the discoveries, however, have been made near Schist, Elbow, Wekusko, and Kississing lakes. One hundred or more mineral occurrences of some merit are known, the main types being sulphide replacement bodies containing nickel-copper or copper-zinc and gold-bearing quartz veins. Some underground exploration or diamond drilling has been completed on 25 or more of the prospects. Up to the present, three ore-bodies, namely, Flin Flon, Sherritt-Gordon, and Mandy, have been proved. Of these, Flin Flon, the largest, is estimated to contain from 16,000,000 o 19,000,000 tons of copper-zinc ore carrying some gold, silver, and lead. Next in importance in regard to tonnage is Sherritt-Gordon, with a calculated reserve of nearly 5,250,000 tons of copper-zinc ore carrying less than $1.00 combined gold and silver.

Jan 1, 1931

By D. F. VanDine, H. George

"The possibility of spoil pile failure at the Kara Kara bauxite strip mine, Guyana, South America, is of major concern to the mine operators. The current mining technique requires the continuous operation of an 11 ms bucket capacity walking dragline on top of 18 metres of freshly spoiled uncompacted overburden material consisting of varying mixtures of kaolinitic clay and quartzitic sand. A field biased geotechnical study of undisturbed overburden and corresponding spoiled material has identified site-specific, non-linear correlations between vane shear strength, standard penetration resistance and spoil pile composition. Readily available geological exploration borehole logs has enabled a composite clay isopach map of the entire mining property to be drawn and critical areas to be zoned according to expected slope stability. Stability has been assessed using simple hand calculation techniques. Use of the resulting stability map provides the mine operators with a means of forecasting the need for appropriate preventative measures at varying stages of mine development, throughout the life of the mine.A similar investigation procedure could be employed at many presently operating and future strip mines.IntroductionThe Kara Kara bauxite stripe mine is located at Linden within the bauxite belt of Guyana in South America. The mining property covers a total area of 88 hectares of flat to gently sloping ground of which some forty per cent is being actively mined or being preparatorily stripped of overburden, prior to eventual mining (George and Gordon, 1979). The regional climate is tropic and humid. Temperatures vary from 16°C to 38°C and yearly rainfall averages 2600 mm, with at least 55 per cent of this precipitation occurring during the 'wet season' months of May to July and December to January."

Jan 1, 1983

By J. A. Meech, C. A. Harris

"The application of control theory in mineral processing is more difficult than in other industries because of the complex nature of the unit processes involved and because of problems with accurate on stream measurement of process variables. Conventional control is based on proportional, integral and derivative functions of a continuously measured error term. Computer control can enhance these actions by incorporating logical routines to switch from one relationship to another. The success of this logical approach depends on our understanding of the process dynamics and the stability of the process and model under all conditions. Typically the model does not apply at all times in mineral processing because of frequent and unmeasurable changes in the ore parameters.Recent advances in the theory of fuzzy sets have led to the application of this science to process control. Fuzzy Logic can be used to develop heuristic or rule-of-thumb controllers with the strategy based on the actual operating practice of experienced plant operators. Control action has increased flexibility through the adaptation of human reasoning. Acceptance of the control system by operating personnel is significantly higher because of their participation in its formulation. The requirement of an exact model is not essential.A heuristic controller has been designed and tested with a computer simulation model of a secondary crushing plant. The results of this study are discussed and future applications of this control technique to other mineral processes are suggested. IntroductionThe application of control theory in mineral processing is more difficult than in other industries because of the complex nature of the unit processes involved. Mineral processes typically are characterized by non-linear relationships between input and output variables. Many of these variables cannot be monitored accurately on-stream and so long time lags on the measurement loop are features of the system. The processes, themselves, often have long time-varying responses while the process loads fluctuate significantly on a short-term basis.Attempts to control these processes have led to the formulation of mathematical models to describe each unit activity. Adaptive techniques have also been tried to compensate and account for process changes and vageries. These approaches are mathematically rigorous so that their complexity and precision limit their usefulness when applied to ""vague"" processes."

Jan 1, 1987

By Randy McMeekin, Chris Twigge-Molecey, J. Peter Blake

The project implementation phase, FEL4, is generally a complex undertaking. The project has been approved for construction and the capital has been allocated. At this point the project team comes under significant pressure to meet the safety, schedule, cost, and start-up committments. For the design team the principal tasks are to finalize detailed design, complete procurement, and issue construction contracts. Design activities must be closely coordinated with equipment and material procurement. A clear engineering plan should be based on well-defined work packages to meet construction, commissioning, and startup requirements. A range of review processes by discipline, area, and third parties assure quality. Constructability, safety, and hazard reviews are performed throughout the design process. Three-dimensional models that incorporate extensive databases help to maximize efficiency and minimize errors. Well-managed projects have a clearly accountable design team, rigorous change control processes, and well-defined workflows. Key individuals from the design team participate in commissioning, operator training, and startup.

Jan 1, 2015

By S. Banisi, J. Marois, A. R. Laplante

"This paper compares the behaviour of gold and ore in the grinding circuit of Hemlo Mines Ltd. Particular attention is given to grinding kinetics, classification behaviour, and liberation. For grinding kinetics, laboratory grinding of gold flakes and silica, 840 µm to 1200 µm in size (14/20 mesh), was also performed to provide a standard for comparison and to study in a controlled environment the mechanisms of breakage, folding , smearing and impacting.Grinding kinetics were characterized at laboratory scale with breakage and selection functions. The breakage function showed that 75% of gold disappearing from the 840 µm to 1200 µm class reported to the 600 µm to 840 µm; this figure is much higher than for silica (46%) or most other minerals, and implies that comparatively fewer fine fragments are produced from the breakage of gold flakes, on account of gold's malleability. The selection function of silica was four times that of gold. At plant scale, the ratio of the selection function of ore and gold increased from 6 for at 50 urn to JOO pm to 20 at 500 um to 1000µm.Observation of original flakes and their fragments with the scanning electron microscope showed that the main mechanism of ""grinding"" from the 840 µm to 1200 µm to the 600 µm to 840 µm class was folding rather than actual breakage. This was confirmed by a measure of individual flake weight. The postulated breakage cycle is that relatively globular flakes become increasingly serrated through grinding; they can then regain their original shape through folding and reflattening into cylindrical and spherical shapes, as the majority does; however, some fragments will at this point undergo actual breakage. Photograhic evidence is presented to support the proposed mechanisms.Smearing of gold unto silica was observed when silica was ground after a gold, and embedding of silica into gold flakes when gold was ground after a silica. Both mechanisms occur whenever gold and harder minerals are jointly ground, and result in ""unliberation"" of gold. It is postulated that smearing of gold onto other minerals plays an important role in explaining how gravity recovery can increase over-all gold metallurgy, especially when used ahead of flotation.Classification of gold in the primary hydro cyclones takes place at a much finer cut-size than ore, 20 µm vs 57 µm. This and the slower grinding kinetics result in high gold circulating loads in the primary loop, 6700%, and a gold content in the primary cyclone underflow (PCUF) is twenty-four times that of the ore. The gold size distribution for primary cyclone overflow is much finer than that of the ore, although they are essentially similar in the PCUF.Liberation, or more accurately ""gravity recoverability"", was assessed with a 7.5 cm (3 in.) Knelson concentrator. It varied between the thirties for the primary mill discharge and two cyclone overflows, to highs of 89% and 92% for the PCUF and secondary mill discharge."

Jan 1, 1991

By E. W. Williams

THE Ontario Research Foundation has developed a process for producing low-density steel shapes by direct reduction of iron oxide powders. The process is a combination of reduction, sintering (without compaction), and carburizing, and has been described by Cavanagh (1). Iron oxide powder, in the form of mill scale or highly concentrated iron ore, carefully sized, is poured into a porous mould. A reducing agent, generally coke breeze, is placed around this mould in a heat resistant sagger which is sealed off and heated to 2,000°F. for a number of hours. The coke/ ore ratio, the particle size distribution, the temperature and time of soaking, and the size and shape of the reduced product, determine the densities and carbon contents attained. The Defence Research Board sponsored a programme of research into some of the mechanical properties of the material (which was named Controlled Density Steel) and this paper is an account of various factors which govern the tensile strength of the steel. The ?practically attainable range of density is from 1.5 to 5.5 gm./ cc. but higher densities are obtained on hot working. This paper, however, is restricted to discussion of results for moulded products.

Jan 1, 1957

By B. I. Boyko

As part of the Ministry of the Environment's Resource Recovery Program, the Province of Ontario has constructed a $13 million "Experimental Plant for Resource Recovery" in Metropolitan Toronto. The technology and unit operations involved in the processing of municipal solid wastes at a rate of 40 tons per hour at this facility are reviewed. Shredding, air separation and classification, screening, magnetic separation and composting are some of the operations featured at this plant. Recoverable commodities expected include paper, ferrous metals, an air-classified light fraction (shredded paper and film plastic), glass and compost. Existing and potential markets for these materials are discussed.

Jan 1, 1978

By Helmut Lerchs

An open-pit mining operation can be viewed as a process by which the open surface of a mine is continuously deformed. The planning of a mining program involves the design of the final shape of this open surface. The approach developed in this paper is based on the following assumptions: 1. the type of material its mine value and its extraction cost is given for each point; 2. restrictions on the geometry of the pit are specified (surface boundaries and maximum allowable wall slopes); 3. The objective is to maximize total profit-total mine value of material extracted minus total extraction cost. Two numeric methods are proposed: A simple dynamic programming algorithm for the two-dimensional pit (or a single vertical section of a mine), and. a more elaborate graph algorithm for the general three-dimensional pit. ASURFACE mining program is a complex operation that may extend over many years, and Involve huge capital expenditures and risk. Before undertaking such an operation, it must be known what ore there is to be mined

Jan 1, 1965

By R. H. Wallis

Weighted moving-average contour maps have been constructed for molybdenum, copper and zinc using 7850 stream-sediment samples from 5430 square miles (14,063 sq. kms) of south-central British Columbia. Regional trends for molybdenum and zinc are northeast, north and northwest and those for copper are north and northwest. These trends are interrupted by zones markedly low in metals . The metal-rich trends cross rocks of different lithology and age and thus appear to be structurally controlled. The northeast trend may have exerted control on metal distribution at two different times.

Jan 1, 1978

By S. J. Cook

Copper, a world commodity, and the first metal used by man, played a great part in the beginnings of modern civilization, which rests so dependently on the utilization of metals. Then, long after the close of the so-called 'bronze age,' when iron and steel had attained great prominence as the world's most important metals, the practical application of electricity to industry and commerce, for the improvement of every phase of man's multitudinous activities, gave a new impetus to the production of copper. Improved metallurgical practice made it possible to work low-grade properties at a profit. Research disclosed many new uses for copper. The metal, now produced from the mines of the world in the proportion of about one pound to every 50 tons of pig iron, has attained an importance which rivals that of iron and steel in the commerce and daily life of every nation. New fields of copper-bearing ore have been discovered in Canada in recent years. Established mines in the United States and Chile are producing on a great scale. Africa looms up as one of the great question marks in the future of copper. Whereas, a few years ago, the end of the world?s resources was predicted as being in sight, the evidence now available seems to show that the copper production of the world is likely not only to continue, but to increase for a long time yet to come. Canada's future in copper is a great subject; in the present paper only a few of the most outstanding factors affecting Canada's destiny in this large field may be noted, but if consideration of the points raised herein serves to focus attention on the magnificent possibilities of Canada as a producer of copper, the preparation of the paper will be more than justified.

Jan 1, 1928

By Vic Briccardi

Energy Management Challenges The Holistic Standard to Energy Management Energy Management Information System (EMIS) "Best Practices?: Energy Management Maturity Curve De Beers Canada Profile & Mine Locations Significant ROI Driven by Real-Time Energy Visibility Mining Energy KPI?s Summary: What Does EMIS Deliver? Q&A Session

May 1, 2013

Éléonore Project Highlights Éléonoreis a multi-million ounce, high grade gold discovery in Québec Currently at the advanced exploration and engineering studies stage Excellent potential for expansion Underground mine with potential for small open pit Excellent infrastructure including road and high quality/low cost electricity within 70 km Les Mines Opinaca Ltée, a 100% subsidiary company of Goldcorp, was created to manage and operate the Éléonore Project

May 1, 2007

By Ross D. Lawrence

"IntroductionOne of the methods used when applying the Market Approach to the valuation of a mineral exploration property is known as the Joint Venture Terms Method. The method is particularly useful for the valuation of early-stage exploration properties. Unfortunately, valuators are sometimes imprecise in distinguishing between joint ventures and other types of transactions.At VALMIN '94, Bob Appleyard1 proposed that, if one ignores the time value of money and the probability that the expenditure commitment would be completed, the formula to calculate the value ($V) of a property owned by Party B at the time of the deal would be:$V =$Ex (100-1%)/1% (Formula I)Where $V is the value of the property2Where $E is the expenditure commitment by Party A, andWhere 1% is the percentage property interest to be earned by party A.At PACRIM '99, Mike Lawrence and Graham Dewar3 referred to this method and suggested that there was an ambiguity in the formula proposed by Appleyard in 1994. Mike Lawrence referred to this problem again at VALMIN '014•Lawrence & Dewar suggested that the formulashould be:$V100% =($Ell%) x 100 (Formula 2)Where $V 100% is the value of the entire property,Where $E is the expenditure commitment by Party B, andWhere 1% is the percentage property interest to be earned by Party B.Subsequently, there has been considerable discussion in the AuslMM Bulletin5. In my view, this discussion has touched on a number of useful points, but generally has overlooked one essential element needed for an understanding of the correct application of the N Terms method. That essential element is to understand that there is a material difference between (1) entering into a joint venture arrangement and (2) the purchase of an interest in a property."

Jan 1, 2003