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By Sylvie Brassard

Available information ?? InfoMine: mineral properties ?? Metals Economics Group: budgeted exploration expenses ?? MineScan: Canadian and American Mining Companies ?? Statistics Canada: Canadian Direct Investment Abroad, by Sector in the world OR all sectors by Country

May 1, 2008

By D. H. Pulling

Statistics for copper consumption from various sources show that the importance of production from secondary sources is increasing. This is of particular significance in countries such as the U.K ., which are totally dependent on secondary material for the supply of home-produced copper . A brief survey of the U.K . industry has shown that, in the past, relatively high profit margins have not encouraged high cap ital investment and development of more sophisticated operating techniques, but set against a background of rapidly escalating operating and energy costs , together with an ever-increasing demand for copper , it is anticipated that the industry will see great changes in the near future. With this in mind, an experimental furnace for continuous smelting of copper-bearing scrap has been developed at the University of Birmingham. This furnace has been designed to combine the conventional operations of blast furnace or reverberatory smelting, usually followed by converting, in one unit, and incorporates many of the features of the WORGRA and Noranda processes for continuous primary smelting . It consists of a long, sloping channel, constructed of chrome-magnesite refractory, which: is churned near the top. Smelting is effected lower down the channel, where iron, etc., in the scrap is oxidized and slagged off with silica flux. Provision is made for oil injection to increase oxidation rates. Metal can flow from the bottom of the channel, and slag from the top, so that a counter-current flow is achieved. The approximate molten capacity is 25 kg. Various scrap charges, both synthetically made and as supplied from various industrial smelters, have been successfully smelted. Metal of 83 -95 % Cu has been produced, depending on the original charge composition and the degree of air injection, although air injection was also found to considerably increase the copper loss to slag. Recoveries of other valuable non-ferrous metals in the charge were good.

Jan 1, 1977

By David Davidson

Overview- Points To Be Addressed ? Review the building blocks of a successful and vibrant industrial economy ? China?s current position in the global economy ? China?s voracious appetite for raw materials ? Distortion in import/export trends ? Areas of strategic importance for China - Steel and its components - Agriculture self sufficiency - Energy now and for the future ? Do current valuation techniques fairly value ?strategic? assets? China ? The Economical Miracle - Massive shift in population from rural to urban - ?Middle class? growing rapidly, hence strong consumer growth - China is the manufacturing center for the world ? cheap labour and - modern facilities - Infrastructure build out ?US$585b stimulus package and 5 year plan - Rail ? 30,000 kms of new track planned by 2020 - Power ? 50% capacity increase, including 35 nuclear reactors - 100 major new airports - State of the art process and manufacturing facilities - Port capacity ? 100m TEU capacity increase by 2020 Class 1 national highway ? 35,000 km?s by 2020

May 1, 2010

By Raj K. Rajamani, Nikhil Dhawan

"Agglomeration has become common pre-treatment step to improve heap leach percolation thereby recovery, the fundamental understanding of the agglomeration process for crushed ores is still lacking. Agglomeration is required for ores which either contain excessive amounts of clay or an excessive quantity of fines generated during mining and crushing. Numerous experiments have been carried out in laboratory scale batch drums using different ores. It has been found out that experimental agglomerate size distributions exhibit self-preserving spectra. The self-preserving/ similarity distribution of the agglomerates is found to be independent of operating conditions and is uniquely determined by the size enlargement mechanism. An empirical model based on the absolute difference between moisture applied and optimum moisture was developed. This model uses self-preserving spectra in the form of a Rosin-Rammler distribution function to predict size distribution at different operating conditions. The empirical model was considerably easier to work with plant scale agglomeration drums. Also, a test known as dip test is developed which improves fundamental understanding of the agglomerate formation and growth mechanisms. This test also provides the progeny size distribution of each agglomerate size. The progeny size distribution was analyzed with a model that partitions the particles into a host and guest category. The ensuing partition coefficient identifies the behaviour of a particle as a host for other particles or a guest layering on other particles. This concept helps in identifying the type of agglomerate that would result for a specific feed size distribution. INTRODUCTIONHeap leaching is one of the hydrometallurgical processes that have served as a green and economically viable process for the treatment of low grade complex ores of copper, uranium, nickel, silver and gold (Dhawan et al., 2013). Heap leaching appears to be a favorable candidate for the least energy consuming process for low grade ores. In heap leach operations nowadays a pretreatment step known as crushed ore agglomeration has been implemented (Dhawan et al., 2013). A bed of agglomerates improves the uniform percolation of solution through the heaps of ore. Therefore, it was possible to treat wastes and mill tailings via agglomeration and heap leaching. Agglomeration pretreatment is required for ores which either contain excessive amounts of clay or an excessive quantity of fines generated during mining and crushing (Bouffard, 2005; Dhawan et al., 2013).While agglomeration has become common practice pretreatment step in heap leach operations, the fundamental understanding of the crushed ore agglomeration process is still lacking. The author reviewed publications up to 2012 on the crushed ore agglomeration process and did not come up with modeling studies on the topic (Dhawan et al., 2013). Some of the possible reasons can be the stochastic nature of the process, experimental difficulties, and lack of instrumentation for fundamental studies."

Jan 1, 2016

By Louise Corriveau, Bronwyn Azar, Valerie A. Jackson, Luke Ootes, Jeff Harris

We use the results of new bedrock mapping, combined with geochemical point data and airborne radiometric data (in particular equivalent uranium concentrations) to help determine which geological units in the Paleoproterozoic Great Bear magmatic zone (GBmz) contain elevated uranium. The data collectively indicate that the highest primary uranium concentrations are in equigranular granites and subvolcanic/volcanic porphyries. Notably, these rocks host the majority of known uranium-bearing deposits and/or prospects in the GBmz. We speculate that the uranium in these deposits/prospects was derived from nearby, uranium-enriched rocks and was mobilized by much younger, circulating hydrothermal fluids. Sedimentary rocks of the Thelon and Dismal Lakes groups unconformably overlie the GBmz and are known to host unconformity-type and sandstone-hosted uranium prospects. Most likely, the uraniumenriched rocks of the GBmz acted as a uranium donor to these overlying sedimentary basins. The method of investigation employed in this study may be applicable to other ‘granitic’ terrains in order to identify regions with favourable rocks for uranium exploration.

Jan 1, 2013

By Patrick Rennkamp, Wolf-Dieter Trodel, Andy Fearn

"The Jansen shafts are completed using purely mechanical excavation. This paper summarises the geology, a description of the shafts, the method used for excavation and the results achieved along with the challenges encountered and the solutions developed during the project. This experience is now being applied in the next generation machines and shaft sinking processes. This pioneering approach is changing shaft sinking in soft and medium to hard rock. INTRODUCTION The Jansen Mining project located approximately 150 km east of the city Saskatoon is the location of the BHP owned potash mine with an expected mining output of eight million tonnes annually upon completion. Mining contractors DMC Mining Services have used two Herrenknecht Shaft Boring Roadheaders (SBRs) to excavate the two blind shafts with an approximate excavation diameter of ten metres (inner diameter approximately 8.3 m) to depths of -975 and -1005 metres, respectively. The SBRs excavate the rock by a partial-face cutting method, using a transverse cutting drum mounted on a telescopic boom. The excavated rock is then conveyed away from the bench by an innovative pneumatic system and transferred into muck buckets to be hoisted to the surface. No drilling and blasting was done to keep to the BHP philosophy of using only mechanical excavation for this reference project. BHP VISION – MECHANICAL EXCAVATION BHP focused on mechanical excavation at Jansen due to the following perceived benefits: 1.No workers in the excavation chamber (shaft bottom), minimizing the exposure to traditional shaftsinking hazards associated with working in the shaft bottom. 2. Minimal damage to the rock fabric reducing the need for ground support and avoiding potential impact damage to freeze tubes located around the shaft. 3. Accurate excavation diameters with no overbreak, reducing volumes of rock to be removed and replaced with concrete lining."

Jan 1, 2019

By R. R. Potter

"New Brunswick became a separate province in 1784, shortly after the influx of a large number of Loyalists from the United States. Many of these people settled along the Saint John River, including the area of excellent farmland near the present town of Woodstock. There were indications that some of these early settlers recognized iron formations in the vicinity of Woodstock about 1820, however the nature of the deposits was not known until 1836 when Dr. C. T. Jackson, a geologist commissioned by the State of Maine, investigated the mineral potential of the area. Jackson(1) described the ""ore"" as compact red hematite yielding 44 per cent pure metallic iron, and suggested that sizable tonnages may be present. It was about this time that an extensive limonite deposit was found in north-central Maine, near Mt. Katahdin. Other iron depostis were found in the Nictaux area of Nova Scotia, and a few years later at Londonderry* (Fig. 1). In 1837, Richard Ketchum of Jacksonville, on whose land iron ores had been found, petitioned the provincial government to incorporate a company. After much study, the York and Carleton Mining Company Bill was passed on March 15, 184 7. Several other petitions were passed permitting the company to construct roads, obtain woodland, etc. (2) . The first blast furnace was erected in 1848 on the west bank of the Saint John River near the mouth of Lanes Creek."

Jan 1, 1999

By J. U. MacEwan

THE basis on which the modern metallurgical industry is operated is the endeavour to attain maximum return in purchasing power for the least expenditure of energy. This has always been the general objective of the industry, as of all industries. In recent years, however, it has received a new emphasis. Today, as never before, increased attention is being directed to the detailed study of plant operations and the application of scientific knowledge and of business principles in order to achieve the maximum efficiency. This new emphasis is the result in large part of the new problems and conditions with which the industry has been confronted, chief among which are the following: (l) Development of new ore-bodies and the treatment of complex ores. (2) Necessity of achieving a greater degree of purity in some of the metals in order to meet the newly discovered demands for some of the industrial metals. (3) Discovery of new markets for many of the metals, either in pure form or in the form of alloys. ( 4) Change in values, absolute or relative, of some of the important metals. (5) Increasing scale of investment in expensive plant and equipment, which makes imperative most efficient utilization if total unit costs are to be kept to a minimum. (6) Increasing scale of operations in some important branches of the industry, which also makes essential maximum efficiency in organization, administration, and operation. The success with which the metallurgical industry has met the problems created by these changing conditions has been due primarily to the following factors: (1) Results of research and experimental work carried on by universities, government laboratories, and many private corporations in the industry itself. (2) Closet study of every detail of plant operation, both from the technological and from the economic point of view, with the object of increasing plant efficiency. (3) Interchange of information and experience amongst the operating companies. It is only by the concerted efforts of numerous investigators and experimenters that the underlying fundamentals of plant operations can be learned. The exchange of results permits their easy assembly and correlation with maximum benefit to the whole industry. Unnecessary duplication of research and experimental work is avoided and the industry as a whole is able to reap the fruits of this work with the maximum of-speed and efficiency. (4) Advances made in recent years in so-called 'scientific management' in industry as a whole and the application of the principles learned to the metallurgical industry. A review of the modern trends in extractive non-ferrous metallurgical processes illustrates the afore-mentioned new conditions and problems, and gives some idea of the methods by which they have been and are being surmounted.

Jan 1, 1937

By Garnet T. Page

"ABSTRACTThese societies •can help in such aspects of a vocation.al guidance program in secondary schools as: provide vocational and technical information, and assist with vocational exploration, such .as plant visits, films, etc. -as .an aid to the student in making a self-inventory. Evidence is increasing that employers' needs for engineers and scientists will not be adequately met in the future. Therefore, the E.I.C., C.I.M., .and C.I:C. recently revised and extended the activities of the Canadian Counselling Committee on Engineering and Science. This co-•operative .action is to be integrated with the educational system, nationally .and locally, and with provincial associations •of engineers and other groups interested in the provision of vocational information in engineering and science.DEFINITIONTHE scientific treatment of any subject requires consistent use of carefully defined terms. The National Vocational Guidance Association of the United States studied the problem of the definition of vocational guidance for .about 16 years, and in 1937 finally arrived at:""Vocational guidance is the pro-cess of assisting the individual to choose an occupation, prepare for it, enter upon and progress in it. It is concerned primarily with helping individuals make decisions and choices involved in planning a future and building a career -decisions and choices necessary in effecting satisfactory vocational adjustment.""RANGEAs a school enterprise, vocational guidance begins at that point in the individual's life when he finds it necessary to make choices that have a definite significance for his future vocation."

Jan 1, 1952

By J. -C. Parisien-La Salle, D. Blais, G. P. Demopoulos

"In this work the dissolution, precipitation and adsorption behaviour of gold in acidic iron sulphate media containing small amounts of chloride ions is investigated via batch laboratory tests and OLI thermodynamic calculations over the temperature range 25-250°C. Chloride ions may be present in industrial pressure oxidation/pressure leaching (POX/PL) operations due to elevated water salinity levels or due to intentional addition as is the case of the CESL Copper Pressure Leaching Process. Thermodynamic calculations show that AuCl4 - may form depending on the free Cl-/Au ratio and temperature, its stability increasing with increasing Cl- concentration and decreasing with increasing temperature. On the other hand during POX/PL, we know that massive precipitation of iron in various hydrolysis products and compounds occurs. Hence of interest is the question how AuCl4 - that may form during leaching interacts with the iron precipitation products. Gold(III) chloride was found to co-precipitate with iron(III) (oxy) hydroxides and arsenates forming in the autoclave but not with natrojarosite. Upon further investigation it was discovered that activated carbon added in the autoclave (as done in CIL) acts as preferential sink for the mobilized gold, hence opening the potential for the development of a direct cyanide-free gold recovery process in acidic sulphate leach reactors.INTRODUCTIONThe recovery of gold from ores and concentrates has evolved over the years with processing routes becoming increasingly complex. Given the high value of gold, any reduction in losses during recovery operations constitutes an important economic benefit. One such loss that needs to be addressed is the potential solubilisation of gold during pressure oxidation (POX) of refractory sulphidic gold feedstocks. For example, Agnico Eagle Mines reported a loss in gold recovery due to the formation of a gold chloride complex (Garofalo, 2009). Gold is known to form complexes in solution, such as gold(III) chloride, if an excess of chloride ions are present. The fate of such soluble gold chloride during pressure oxidation and the subsequent neutralization of the acidic discharge slurry will determine if gold is lost or recovered in the downstream cyanidation operation. Thus it is of interest to know under what conditions gold chloride may stay soluble or co-precipitate along primary (formed in the autoclave) or secondary (formed during neutralization) precipitates. Furthermore, the mode of co-precipitated gold, such as adsorption on iron compounds, like goethite and hematite (Machesky et al., 1990; Nachayev, 1984); substitution in one of the precipitated phases; or finally chemical reduction to metallic state would have consequences in terms of gold recovery."

Jan 1, 2012

By H. H. Bleakney

The merit of reduction-in-area as a criterion of quality in metals is shown to lie in its influence on breaking stress, but the virtue of elongation is not easy to find. In order to assess the value of elongation, either as a measure of quality or as a guide to design, it will be necessary to separate the overall de-formation occurring in tension tests from the localized deformation associated with localized reduction in area. The obstacles to a successful solution of this problem have been shown to be more formidable than is generally appreciated, and a new solution to the problem has been suggested. This solution involves a de-vice by which an electric circuit is broken when the particular value of strain is reached that is to be taken as the point of separation between general and localized deformation. The report presents results from a number of tests on both low-carbon and alloy steels. These results indicate that the selected criterion of separation is accurately identified by the proposed method; that it

Jan 1, 1962

By C. O. Stee

Introduction The property of Siscoe Gold Mines, Limited, is located on an island of three hundred and forty acres in lake Kienawisik, about fifty-two miles east of Noranda and forty-three miles south of Amos, Quebec. Lake Kienawisik is a part of the Harricanaw drainage system and is crossed by the main line of the Canadian National railway at Amos. This waterway is navigable for boats with a draught of six to eight feet. Diesel engines have been the source of power at the property since milling operations were commenced in January, 1929. The power plant as first designed and built was for a milling capacity of 100 tons. Two Polar-Atlas units, each of 200 h. p., comprised the original installation. With the growth of the 'mine, more engines were added until, at the present time, there is installed at the Siscoe what is rated the largest Diesel plant at any mining property in Canada. Definition of a Diesel 'The Diesel engine is an internal combustion engine which works with liquid fuel introduced after, and independently of, the air charge at a time when communication between the cylinder and the outside atmosphere is cut off, and which ignites the fuel by compression-beat and stored combustion-heat unassisted by heat sources outside the cylinder itself while the engine is in stable operating condition"(1).

Jan 1, 1934

By Adam Chrzanowski, Eugene E. Derenyi, Peter Wilson

"The rapid growth of the mining industry in Canada necessitates a reevaluation of existing mining surveying techniques and the development of new methods. In this connection, the Department of Surveying Engineering at the University of New Brunswick initiated a research program, and the major points of investigation conducted to date are as follows: 1. Based on practical experience and theoretical studies, all factors influencing classical shaft-plumbing procedures were analyzed. Refined methods were developed to increase accuracy. 2. The performance of electronic and optical distance-measuring instruments in underground conditions were investigated. In this connection, test measurements were made in various mines, employing four types of Tellurometers, two models of Geodimeters and a proto-type optical range-finder. 3. Tests were conducted and methods developed for the mapping of large underground chambers by photo-grammetric means. The aforementioned points are discussed at some length in the paper. The authors have also indicated areas where further research is needed and suggested ways and means to improve and modernize mining surveying as a whole throughout Canada."

Jan 1, 1967

By R. E. Whitehead, G. J. Prior

"Abstract -Biotite from aplite that appears to have crystallized simultaneously with disseminated Cu-Mo mineralization at MacLeod Lake in northern Quebec yields K-Ar dates in the range 2032 ± 44 Ma to '2f1:)1 ± 47 Ma. The mean value, 2065 Ma, is some 400 Ma younger than the 2485 ± 64 Ma date obtained from a hornblende concentrate separated from a granodiorite sill that is spatially, but apparently not genetically, associated with the disseminated Cu-Mo deposit. The mean biotite date of 2065 Ma at MacLeod Lake, a K-Ar date of 2055 Ma reported from an area 50 km east of MacLeod Lake and published dates of about 2000 Ma for galenas from the Chibougamau Cu-Au ores, suggest a widespread thermal and mineralization event, in that part of the Superior Province east of James Bay, that differs from the common late Archean mineralization that is related to volcanism and metamorphic-intrusive activity.Sommaire - Les datations au K-Ar sur des biotites qui auraient cristallisé en même temps que la minéralisation disséminée en Cu et Mo dans une aplite mise en place au Lac MacLeod, au nord du Québec, s'échalonnent entre 2032 ± 44 Ma et '2f1:)1 ± 47 Ma. La datation moyenne, soit 2065 Ma, est d'environ 400 Ma plus récente que la datation obtenue pour un concentré de hornblende extrait d'un fùon-couche de granodiorite qui est spatialement mais ne serait pas génétiquement as­ sociée à la minéralisation disséminée en Cu et Mo. La datation moyenne de la minéralisation au Lac MacLeod, soit 2065 Ma, la dataion au K-Ar à 2055 Ma citée pour une région à 50 km à l'est du Lac MacLeod, de même que les datations d'environ 2000 Ma établies pour des galènes qui se trouvent dans le minerai aurifère et cuprifère à Chibougamau, suggèrent un phénomène thermique répandu qui aurait produit la minéralisation dans cette région à l'est de la Baie James, dans la province du lac Supérieur. Ce phénomene serait différent de celui qui aurait produit la minéralisation répan­ due d'âge archéen tardif qui elle serait associée à l'activité volcanique et à l'activité intrusive accompagnée de métamorphisme."

Jan 1, 1992

By C. F. Starr

This paper deals with the various types of cable in use in mines, with special attention paid to their construction. There will be a few comments regarding the different insulants, jacketing materials and armouring used, depending on their application. Governing standards and the differences therein will also be discussed.

Jan 1, 1969

By J B. Maughan

Gas and oil seeps have been known in Quebec for more than one hundred years. These occur in three main areas which contain sedimentary rocks with a total thickness estimated to vary from 6,000 to 20,000 feet. The strata in these areas are similar in many respects to those in producing areas of southwestern Ontario and the Appalachian basin, and the prospects for finding and developing commercial reserves of oil and gas in Quebec would therefore also appear to be favourable. Little of the exploratory drilling to date has been con-ducted in a systematic manner, and most of the drilling has utilized improper or inadequate equipment. Many wells have also failed to adequately test and fully evaluate the principal zones of interest. Relatively high drilling costs have hindered systematic exploration; however, with improved portable equipment, it is expected that future wells can be drilled with greater efficiency and at less cost. Most of the mineral rights in Quebec are held by the Provincial Government, and acreage can still be leased in large blocks on favourable terms.

Jan 1, 1964

By BARRY BANNATYNE

Gypsum in Manitoba is quarried from the Jurassic Amaranth Formation a1 Gypsumville and Harcus; it has been mined near Amaranth and Silver Plains. At Gypsumville, gypsum is carbonate- free but has thin clay laminae between gypsum layers; the rock is folded in places, and some anhydrite is present. At Harcus, gypsum contains scattered dolomite, both as patches in a penemosaic pattern and as thin layers; small chalcedonic concretions also can be found. The quarry at Harcus was opened late in 1978 and currently produces about 100,000 tonnes annually. The two inactive mines near Amaranth operated from 1932 lo 1963 and from 1967 to 1970, and contain a central anhydrite layer. The mine near Silver Plains was flooded from an underlying artesian aquifer in 1975 and has not been reopened. Manitoba gypsum is used in cemem plants in Mani1oba and Saskatchewan and in wallboard plants in the three Prairie Provinces.

Jan 1, 1984

By F. H. Wheeler

CONSIDERING the nature of this audience, I perhaps, in addressing you on the subject of air transportation as related to the mining industry, should speak with tongue in check or at least with some reservation. I know full well that many of you, veterans in the great mineral development in Canada, are perhaps more conversant with the overall aviation picture than I, for aviation to you has been the means to an end, and in many instances has been part and ?parcel in the success of your particular projects, in the form of the initial means of transport. I feel, however, that we in this room today have somewhat parallel geographic interests - yours in relation to what is in the ground, mine in the air - and also in the forests and in the streams - aviation, hunting, and fishing - things which have occupied my attention practically all my adult years. In the light of what has gone. before, and in view of present developments, I think you will agree with me when I say that I do not think there could be a more intriguing pursuit than playing a hand in rolling back Canada's tremendous northern frontiers, even if, at this stage, we have made but slight impression on the untold opportunities which lie in our wide-spread, undeveloped areas.

Jan 1, 1956

By D H. Sharp

The Quebec Cartier Mining Company produces iron concentrate for twelve months of the year from Port Cartier. This J>Ort is designed to handle ship varying in size from 3,000 to 100,000 d.w.t., requiring 50 feet of water at low tide. The harbour was built on shore for reasons of economy and layout, after considering many more conventional offshore designs. It provides for heavy oil bunkering, tanker off-loading, a heavy lift derrick and freight handling, besides ship loading and mooring. The weather for the previous fifty years was studied to enable wind and wave conditions to be accurately assessed for design purposes, and to determine probable lost time due to adverse weather conditions through-out the year. The first ship to be loaded was 60,000 d.w.t.; the second, 20,000 d.w.t. The latter entered the harbour after dark, under its own power, following a tug through the partly dredged narrow entrance. Large ships use tug assistance. Ships may leave the loading berth with the other berths occupied.

Jan 1, 1963

By Rene Cane, V. I. Lakshmanan, John Starkey, Richard May

"The Agrium Kapuskasing Phosphate Operation mines and processes up to 6,000 t/d of phosphate ore. Run-of-mine crushing to minus 6 inches is done in a toothed roll-crusher, while grinding is done in a SAG/ball mill circuit with no coarse recycle classification of the SAG mill discharge. The primary grinding mill is an 18 ft. diameter x 9 ft. EGL, 1500 HP variable speed SAG mill and the secondary mill is a 13 ft. diameter x 21 ft. long, 2000 HP fixed speed, ball mill. When hard ore was treated, the SAG mill restricted the tonnage that could be ground. When soft ore was treated, the ball mill and spiral classifier overloaded and restricted throughput.Recommendations from a plant benchmark and an ore hardness testing program, on how to better utilize installed energy in the Agrium SAG mill when treating soft ore, and how to obtain best results when treating hard ore, were checked in a pilot plant investigation in the 3 ft. diameter Starkey-PRO Pilot SAG Mill. Correlation between the ore hardness testing and the results from the 3’ Pilot SAG mill was very good. In addition, the work indicated the results that could be expected for the different ore types when using either smaller SAG discharge grates and/or a vibrating screen with 10 mesh square opening cloth.INTRODUCTIONAgrium Kapuskasing Phosphate Operation consists of a 6800 t/d open pit mine and a concentrator, near the Town of Kapuskasing in Northern Ontario. The two major ore types are sandy ore and cemented ore. Sandy ore is fine, soft and easy to grind in the SAG mill while cemented ore is harder, more blocky and difficult to grind in the SAG mill. The ratio of sandy to cemented ore in the deposit is thought to be in the order of 80:20 but can range as high as 5050, so it was important for the grinding circuit to have the ability to treat sandy ore alone."

Jan 1, 2002