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By Sub-Committee of the Committee on Research

"THE FOLLOWING REPORT was compiled by a sub-committee of The Metallurgical Society of CIM, Committee for Research, and represents a viewpoint of the steel industry in Canada. The objective was to define those areas in which the industry considers that external sources of Research and Development are a necessary function in supporting the in-house R & D conducted by the industry.On future occasions, the viewpoints of other metallurgical industries, such as those of nickel, copper and aluminum, will be presented. The report is divided into several sections: 1.-R & D Spending by the Steel Industry (a) Memberships in Recognized Steel Research Centres (b) Memberships in Recognized Industry Associations (c) Sponsored Research at Recognized Centres (d) Sponsored Research at Universities(e) Sporadic Research 2.-Areas for Research and Development(a) Instrumentation (b) Environment Control (c) Refractories (d) Sponsored Research at Universities(e) Electric Furnaces (f) Continuous Casting"

Jan 1, 1970

By C. D. Williams

The following paper deals with some of the aspects of the law as it relates to the oil and gas industry in the Province of Alberta, but it should be stated here that consideration of this large subject will be confined to discussion of only those laws, rules, and regulations which affect actual exploratory operations. The paper will not touch on those branches of the law which deal with such matters as income tax, customs, and other kind red subjects which are of a highly technical nature and which are more properly the field of the specialist. Generally speaking, any system of law consists of certain major components. There must be, firstly, a national authority capable of ensuring the existence of the state itself and of maintaining the stability and continuity of its institutions; secondly, a philosophy of government covering the relationship of the state to the individual and of the individuals to one another; thirdly, a body of law to effect the purposes of the philosophical principles; and, fourthly, a judiciary to arbitrate any disputes that may arise from such relationships. All of these components and the system itself are, of course, subject to a varying degree of modification with the changing times and with the influence upon them of other systems of law. Now. while it is true to say that all systems of law comprise these similar basic features, it is apparent that the end result of any two systems of law in their impact upon the individual may be quite different.

Jan 1, 1951

By J. Weyer

"Threshold limit values (TLVs) for NO and NO2 have been reduced drastically in 2016. Emissions of diesel engines have been reduced in the last decades. In many cases this is not enough to stay under required TLVs. Remaining gas in the blasted rock is set free during loading and transport. At the end, only a combination of measures with a further reduction of diesel motor emission, replacement of diesel driven vehicles by electric equipment, new explosives with reduced NO and NO2 production, changes in the organization and effective ventilation measures can ensure that the TLVs are not exceeded. KEYWORDS Blasting fumes, Gas measurement, Gases, Threshold Limit Value (TLV) SHORT HISTORY OF EXTRACTION OF RAW MATERIALS The extraction of raw materials—besides haulage and transport—is one of the main processes in mining and tunneling. The principal objective is the creation of a material which can be transported from the place of extraction (face) to another place for further processing or direct use. Furthermore, recently a desired grain size distribution has become more important. A revolutionary development took place in the course of centuries. With the use of primitive tools like shovels, chisel and iron in the 12th/13th century in Freiberg, ore mines performances of 12 16 cm per man and week could be reached in cross section of 1 m2. Recalculated with an assumed average density, this is a performance of 0.006 t/h. With the introduction of black powder into the subsurface in 1627 by Caspar Weindl in the city of Schemnitz (nowadays Banska Stiavniza), performances increased. A part of the hard extraction work was now done by the explosives. But first in 1767, it was recognized in a mine in Freiberg that more than 1 hole could be drilled (hand-drilling) and blasted. This discovery was so important that a plate with an inscription describes this event. The performance was increased more than 10 times compared to the extraction with chisel and iron. Since this time, drilling and blasting has been the most important innovation force for the increase of the performance. Problems with noxious blasting fumes led to the construction of the first tunneling machine by Henry Joseph Mouse in 1846 (beside shield machines from 1825) (Stack, 1982)). The triumph of mining machines started only interrupted by the two world wars. The development of hard rock boring machines (including roadheaders) was enforced after 1945. An almost complete extraction by hard rock boring machines was predicted for the turn of the millennium. And, indeed, one could find powerful machines in Canadian potash mines which were able to mine 1000 t of potash in 1 hour. That was an increase in the performance by several powers of ten. But already in the 1980s, it was recognized that the ambiguous goal could not be reached. Problems with wear of the tools, radius of curves, minimal length of openings, size and costs of the machines led to a more or less parity between drilling and blasting on one side and machines on the other side, of course depending on the field of use. For this reason, drilling and blasting is still the dominant extraction technology for raw materials. In the development of drilling and blasting technologies, the focus was mainly on the improvement of the safety but also on the increase of the blasting power and performance. Examples are tests for the increase of the power of ANFO explosives which were carried out in the 1970s and 1980s, in the former teaching mine “Reiche Zeche”. In the 1980s vehicles for loading and mixing of ANFO explosives have been developed, the blasting cab sensitivity of ANFO has been increased, emulsion explosives have been developed and up to now further developments like PMMA LOX EX explosives are on the way. At the turn of the millennium, 6 million t/a explosives have been used worldwide. Annual rates of increase of 2% have been predicted (Weyer, 1999). Meanwhile the focus changed from an increase of the performance"

Jan 1, 2019

By L. Paulino, R. A. Camilli, J. Yamamoto, J. C. Araujo

The first paper presented on this work [1], showed how bath ratio was increased from 78% to over 95% using a structured approach to reduce bath chemistry variability. This update will illustrate the steps taken and update the results presented earlier, showing the effects of long power interruptions and several load reductions as well as load increase during the period from 1999 to 2005. Current efficiency was affected by such processes upset; however, bath ratio in range (±0.05) is still higher than 90%, even after an increment of more than 6 kA. This review will explain each of the steps taken to reach stability in this critical smelting parameter.

Jan 1, 2006

By Unknown

Diesel locomotives for underground haulage have been used in coal mines in Continental Europe for twenty-five years or more. In Great Britain, it was not until 1935 that permission was granted to use them in gassy coal mines, but since that time they have been employed in increasing numbers both in gassy and non-gassy coal mines and in metal mines. Their use underground in coal mines in the United States is still prohibited and the same was the case in Canada until 1946, when permission was granted to operate a Diesel underground in the Adanac mine of West Canadian Collieries, Limited, at Bellevue, Alberta. The locomotive used here is a 50 h.p. Hunslet Mark II. More recently, a 100 h.p. Diesel was placed in operation for underground haulage at No. 18 Colliery of the Dominion Steel and Coal Corporation, in the Sydney coalfield, N. S. Thus, on this continent, Canada has been a pioneer in the use of these locomotives underground in coal mines and there is no doubt that more and more of them will be employed as time goes on. We feel, therefore, that the following notes concerning their design and performance, which we have received from the High Commissioner for the United Kingdom, will be of interest to our members.

Jan 1, 1949

By Funsho K. Ojebuoboh

With several “green” applications on the horizon, bismuth has become an even more important minor metal in the smelting and refining of lead. Smelters with a complex sulphide feed invariably deal with bismuth. Its behavior during the smelting of lead in conventional sinter-blast furnace operation is discussed. Because it readily deports to the lead phase during the refining of lead, its separation from refined lead remained unsatisfactory in early lead production. When commercial requirements of bismuth in lead became more stringent early this century, the procedure where by calcium and magnesium is used todebismuthise lead was developed. The present conduct of this 1936 process, the Kroll-Betterton process, is discussed with emphasis on operational improvements.

Jan 1, 1996

By E. Swartzman

"IntroductionGENERALLY, the necessity for mining coals of higher impurity content, the drive for lower costs by intensive mine mechanization, changing market requirements, and the increasing competition of oil and natural gas, have continued to result in an upward rise in coal preparation, and have necessitated a more intensive study of coal preparation problems.Increasing adoption of •continuous mining equipment, for example, is introducing new problems in coal preparation. Limited experimental work in the United States (1) shows that the effect of the continuous miner on size distribution varies with the characteristics of the seam. In some seams, the fines problem is lessened, in others it is greatly aggravated. Generally there is a decrease in the relative amount of the top sizes (plus 2 in.) and a substantial increase in the intermediate sizes (down to about 1/8 in.). Contrary to expected results•, where continuous miners with vertical-moving cutting heads are used, an increase in impurities in the slack sizes does not necessarily occur where draw-slate is taken. This is because the draw-slate tends to be kicked out in lump form. However, if a seam contains bands •and lenses of impurities they are bound to be in the mined product."

Jan 1, 1952

By R. Rumpold, J. Antrekowitsch

"The continued increase of the automobile production leads to a higher platinum, palladium and rhodium (PGM) demand. Due to the high value of the PGMs the recycle of these metals from automotive catalysts is of special interest. Pyrometallurgical processes, which are only focused on the PGMs, represent the state of the art of automotive catalysts recovery. However, hydrometallurgical recycling processes offer additional recovery of other valuable metals and compounds. The method presented in this paper is based on a combination of hydrochloric acid and hydrogen peroxide to dissolve the valuable metal fraction which can be precipitated afterwards.INTRODUCTIONPlatinum and the corresponding metals from the PGM group, especially palladium and rhodium are well known as catalytic active materials. They support chemical reactions which are inhibited. This effect is used to decrease the amount of harmful compounds like hydrocarbons, carbon monoxide or nitrogen oxides in automotive exhaust gases. The generation of these toxic substances is based on incomplete combustion, which in turn is caused by non-ideal conditions in the combustion chamber. Catalytic converters minimize the harmful compounds by supporting the following Reactions 1 – 3 (Votsmeier et al., 2009).CO + ½ O2 ? CO2 (1)CnHm + (n + ¼ m) O2 ? n CO2 + ½ m H2O (2)2 NO + 2 CO ? N2 + 2 CO2 (3)Platinum and palladium are very effective for the oxidation (Reactions 1 and 2), while rhodium supports the decomposition of nitrogen oxides by carbon monoxide (Votsmeier et al., 2009). The classical three way catalyst was a platinum – rhodium combination with a Pt:Rh ratio of 5:1 (Hagelüken et al., 2005). Today the platinum, palladium and rhodium ratio is highly variable and strongly depends on the engine type as well as on the car producer. Diesel engines are operated with a super stoichiometric air addition in comparison to spark ignition systems. Therefore the exhaust gas composition and off gas temperature is different. Based on the high oxygen amount, diesel engines produce less carbon monoxide and hydrocarbons but more nitrogen oxide in contrast to gasoline engines. This leads to various requirements for the catalytic converters."

Jan 1, 2012

By Michael Arriagada, Ivan Arriagada

"As mines return to shafts to economically exploit deeper reserves, two methods mine owners use to minimize short term costs are: sinking shafts in phases and refurbishing old, existing shafts. While there may appear to be benefits to utilizing existing infrastructure, often this is not the case, resulting in missed deadlines and added costs. Similarly, if proper long term planning is not executed when sinking a shaft in phases, additional costs and downtime will be accrued. This paper will take an in depth look at both of these options with an eye towards optimizing costs, minimizing downtime, and facilitating construction. INTRODUCTION With the onset of mechanized mining and large capacity trucks, many mines turned away from shafts and began to use ramps to haul ore to surface. However, continual exploitation of mineral reserves located closer to surface, combined with the subsequent unearthing of additional resources at greater depths, forced mines to go deeper and deeper to extend the life and keep the operation running. In shallow mines, hauling ore by truck was an economical option. However, as mines get deeper, driving ramps takes additional time, and hauling over longer and longer distances becomes less economic, both in terms of cost and time. For this reason Mexico, in particular, has seen a jump in the number of shafts which have been put into production, as well as having a number of shafts in different stages of development and still more in the conceptual stages. Many of the shaft projects in Mexico are being designed in phases, with the hoist and equipment purchased capable of reaching the ultimate planned depth of the shaft, but with sinking operations stopping short at an intermediate depth. A loading pocket is then installed to start exploiting mineral at this depth sooner, with subsequent phases planned for a later date using either a rock pentice or bulkhead to separate the sinking operations from the active shaft above. Currently, we are directly involved in two such projects which are actively being deepened, as well as having seen various others already reach completion. If done properly with the long-term plan in mind, sinking in phases can be a very viable option, allowing for faster production while fully utilizing the equipment at various depths. However, there are many issues which can arise when sinking a shaft in phases that if not properly examined and planned for from the outset, have the potential to eliminate the gains hoped for when it was decided to sink in this manner."

Jan 1, 2019

By G Anders

Underground tests of slusher cables at first might seem to be quite simple and inexpensive. They do, however, take a long time and give results that may be ambiguous and unreliable. Also, because underground test conditions are not exactly duplicable, tests carried out at different times or in different mines could not be compared. An attempt was made to develop a laboratory test method that would provide for all factors affecting slusher cable performance underground in such a way as to make it possible to achieve comparable results from different series of tests by exactly duplicating test conditions. Such a method should also make it possible to vary individual factors systematically in order to give a proper assessment of the effect of changing conditions on cable performance. A set of tests, comparing the same two types of cable both underground and in the laboratory, is described. AN assignment at the Algom Nordic mine called for the comparison of two types of %-in. slusher

Jan 1, 1964

By Lionel C. Piuze

Introduction and Early History The British Canadian Mine is one of four operating properties of Asbestos Corporation, Limited, and is located in the town of Black Lake, Que., five miles southwest of Thetford Mines. In the early days of as1bestos mining, this .property was owned by a few small companies who later became part of the Asbestos Corporation. First .to commence mining operations on the property was the Coleraine Mining Company who, in 1885, began selling part of their large holdings in the area to various asbestos mining interests. Of these, the earliest active companies were Manhattan United Asbestos, the Glasgow and Montreal Asbestos Company, and the Anglo-Canadian, the last named later becoming the Standard and Dominion Asbestos Companies. Extraction of fibre was limited to what is now known as crude asbestos and the methods were primitive. Drilling was done .by hand and the ore was lifted by derricks operated by band winches. These were later replaced by horse power, but it was not until 1887 that the first steam-operated boom derricks were introduced, at the Anglo-Canadian mine. The ore was hand cobbled and the asbestos roughly classified and bagged. The waste rock, which by today's standards contained a considerable percentage of marketable fibre, was dumped near the pit. The first attempt to separate the asbestos from the host rock by mechanical means was made in 1888 by the G1asgow and Montreal Asbestos Company, then known as the Scottish-Canadian Asbestos Company, whose mill, erected in that year, was the world's first asbestos mill. Though the equipment was crude, the principles employed were the same as those used today with much larger units. The next steps were the use of rock drills, the adoption of steam rail transportation for moving mill rock, and conversion to the more flexible cable-derrick hoisting.

Jan 1, 1950

This paper comprises a description of on-stream analysis instrumentation, including sample handling, X-ray optics and data processing. It also includes a discussion of some typical applications of an on-stream analyzer as related to the mineral processing industry. Introduction T WO automatic X-ray spectrometers have been developed for the simultaneous analysis of as many as six elements in a given sample. These instruments, namely the On-Stream Analyzer and the new Vacuum Simultaneous Spectrometer, have been designed specifically for process control in industry where large numbers of static samples or a number of flowing sample streams must be analyzed continuously with both speed and accuracy. This paper is concerned particularly with the application of these instruments for the continuous analysis of dynamic samples. The Instruments The On-Stream Analyzer and the Vacuum Simultaneous Spectrometer are intended to serve industry by offering two basic approaches to the problem of continuous sampling of flowing sample streams. The On-stream Analyzer (Figure 1) is designed for the completely automatic and unattended analysis of flowing sample streams in a programmed cycle of operation.

Jan 1, 1965

By Z. D. Hora

Brick shales and refractory clays are mined at Sumas Mountain near Abbotsford. Sholes and stoneware clays elsewhere in the province have not been developed. THE SUMAS MOUNTAIN deposit near Abbotsford, 80 km east of Vancouver, has been in continuous production since 1905. The deposit is exposed in a small outlier and comprises a sequence of alternating beds of clay and sand. Beds are of Eocene age. Within the 400 m thick ness of sediments are seven distinctive conglomerate members, some up to 20 m thick, interbedded with fine grained sediments including claystones and siltstone , or "shales". Shale is quarried to produce a variety of bricks, sewer pipes and similar products; it is also used for cement. Several different shale beds have been mined over the years and exhibit a variety of fired colours ranging from buff-pink grey to deep red; pyrometric cone equivalents (PCE) range from 3 to 20. A layer of fireclay 3 to 4 m thick that occurs at the base of the sequence has pinkish white to light buff fired colour and PCE of 30 to 33. It is used as a 266 primary component to produce refractory bricks. The shale is quarried and processed by Clayburn Industries Limited of Abbotsford. Another similar but smaller outlier of the same geological formation is known from Blue Mountain, about 20 km northwest of Mission. Other ceramic clays in British Columbia are reported from Quesnel (7 m bed of white stoneware clay, PCE 17 to 19), Giscome Rapids (25 km north of Prince George, 10 m bed of stoneware clay to PCE 31) and anaimo-Comox area (buff to red firing "shales", PCE 8 to 10-1 12) . From 1959 to 1974 Cretaceous shale from Saturna Island in the Strait of Georgia was used to produce lightweight aggregate. Similar deposits of expanding shale are known from the vicinity of Duncan on Vancouver Island.

Jan 1, 1984

By S. N. Dixon

"Maximizing the value of each tonne of processed ore is the goal for all operations. Cyanidation processing of gold-copper ores has been challenging since its first use in 1889. The current practice treats a bleed or the total flow of mill solution to recover copper as copper sulfide (by sulfidization, acidification, recycling, and thickening), or to recover the cyanide (by acidification-volatilization neutralization). The process presented uses the adsorption of copper cyanide by carbon and the selective elution of copper from carbon to concentrate copper into a smaller stream. Copper contained in the smaller stream is precipitated as copper cyanide.RÉSUMÉ Toutes les exploitations ont pour objectif commun d’optimiser la valeur de chaque tonne de minerai traité. Depuis sa première utilisation en 1889, la méthode de traitement par cyanuration des minerais aurifère et cuprifère s’est révélée complexe. La pratique actuelle traite la saignée ou le débit total d’une solution de traitement du concentrateur pour récupérer le cuivre sous la forme de sulfure de cuivre (par sulfuration, acidification, recyclage et épaississement), ou pour récupérer le cyanure (par acidification, volatilisation et neutralisation). Le procédé présenté dans cet article utilise l’adsorption sur charbon actif de la solution de cyanure de cuivre et l’élution sélective du cuivre depuis le charbon pour concentrer le cuivre en un plus petit jet. Le cuivre contenu dans ce plus petit jet est précipité sous forme de cyanure de cuivre.INTRODUCTIONProcessing gold-copper ores by cyanidation has been a cost-control challenge since the cyanidation process was first used in 1889. Copper cyanide is stable only in the cuprous state, not the cupric. This factor results in the oxidation of a mole of cyanide per mole of nonchalcocite copper extracted. Each mole of copper extracted forms a cyanide complex with a minimum of 3 mol of cyanide. This cyanide-to-copper mole ratio is required to dissolve gold. The oxidation of cyanide and copper complexation with cyanide results in high cyanide consumption for copper-gold ores, which is a significant operating cost.One challenge in processing gold-copper ore is the cost of cyanide related to the extraction of copper. Processing 10,000 t/d of ore containing 1,000 mg/kg copper and 10% copper extraction yields 1,000 kg/d of copper. Currently, processes to remove copper from cyanide leach solution treat either the total flow of the barren or a bleed of the barren. The two processes used for copper-gold ores are sulfidization, acidification, recycling, and thickening (SART), which produces a copper sulfide product for sale; and acidification- volatilization-neutralization (AVR), which recovers the cyanide from a gas and produces a low–cyanide content solution. This low–cyanide content solution can be recycled to the process or might require additional treatment before being disposed from the operation."

Jan 1, 2017

By R. L. Bishops

This paper discusses some of the materials, processes and systems used in motor insulation. Among the materials mentioned are epoxies, polyesters, mica paper composites and wire enamels. Two processes developed to take advantage of the special characteristics of two of these materials are described, and how these materials are used in several new insulation systems now on the market is discussed. Finally, future trends in motor insulation are outlined.

Jan 1, 1969

By P. W. Billwiller

Abstract The Britannia Mining and Smelting Company, Limited, have replaced diamond drills with percussion drills and tungsten: carbide bits for most of their blast hole drilling operations and have thereby reduced ore breaking costs. Two-inch Carset bits .are used, with one-inch hexagonal Atlas Chippewa alloy steel in 3-foot .and 6-foot lengths. Locally made couplings of Atlas SPS 245 alloy steel connect the rods. The machines used are 31½-inch automatic leyners with lugged or anvil block chucks. For drilling holes below the horizontal, the lugged machines with special adapter rods made from 114- inch solid round Atlas SPS 245 are required. These rods are lugged at one end and a water hole is drilled for six inches into the other end. Over this rod is placed a water swivel which permits the water or air to be sent directly into the steel. A decreased cost per foot, increased footage per shift, and the use of standard equipment and crews are some of the main advantages of tungsten carbide drilling over diamond drilling. Introduction Long-hole drilling with percussion drills and sectional steel was introduced in several American mines some twenty-five years ago. It did not prove very successful, however, because the rapid gauge loss in steel bits necessitated the use of very large starter bits. This in turn rapidly fatigued the straight carbon-steel then in use, made it difficult to maintain the couplings, and resulted in a slow drilling rate. The introduction of the tungsten carbide insert bit and alloy drill still has changed this picture and opened real possibilities for the application of percussion drills to blast-hole drilling. If this type of bit had been perfected ten years ago, much of the research work and experimenting done to apply diamond drills to ore breaking would have gone toward developing the application of the tungsten carbide bit to this problem.

Jan 1, 1950

By D. A. Pirttinen

The promotion of improved coal quality for thermal generation can benefit our national economy. The construction of electric generating facilities in Canada is expanding at a rapid rate to satisfy the demands of a rising population and new uses for electrical energy. With remaining economic water power resources in the process of development, generation from thermal sources continues to grow. The increase in thermal capability has been somewhat arrested by a de-pressed economy, widening of inter-provincial and state transmission networks and decisions to exploit certain water resources before high capital investment is further in-creased by rising construction costs. The introduction of extra high volt-age transmission lines will further delay thermal generation planning, but in due course, when the effects of restrictive factors have been dissipated, steam-electric generation from fossil fuels will rise to considerable proportions. In time, nuclear sources will contribute a growing share to thermal power, but, it is doubtful if nuclear participation will ever displace conventional fuels for steam rising, unless it can be adapted to operate efficiently for variable outputs in peaking service. It appears certain that fossil fueled

Jan 1, 1961

By A. J. MacEachen

"LIKE ALL OTHER NOVA SCOTIANS, I have been thrilled during the past few years with the growing evidence that substantial reserves of oil and gas are being discovered off the Atlantic coast of Canada. There are those in this province who believe that large-scale commercial production is just around the corner, and that when it starts Nova Scotia will begin to float on a sea of royalties. These overly optimistic people, of whom I am not one, are convinced that with the first barrel of oil shipped to market, Nova Scotia can forget its financial problems while its people take on the luxurious lifestyle of the shieks of Kuwait or Saudi Arabia. You and I know, however, that even though offshore oil and gas may turn out to be the greatest gift nature has ever bestowed on Eastern Canada, it may take some considerable time before the reserves can be accurately assessed, before the industry can become fully operational, and before the benefits of production can be translated into royalties and tax revenue, improved public services, new industrial facilities and more jobs. While it is premature for the ordinary Nova Scotian to take on the habit of buying expensive cigars and lighting them with ten-dollar bills, it is not too early for him to insist that governments and industry plan intensively and well for the beneficial exploitation of undersea resources."

Jan 1, 1973

By Edward I. Renouard

"THE mineral industry is constantly undergoing changes and facing challenges, and today we are in the midst of another serious one -namely, manpower requirement at every level in the mines, shops and plants. In the not too distant past we had a situation where labour was plentiful, although the equipment, by present-day standards, was quite inadequate, and that's easily understandable when you look back at the primitive methods by which our Western mines were first developed and operated, and then improved by the inventiveness and ingenuity of man.I'd like to show you a few slides from drawings made by Buck O'-Donnell which illustrate some of yesterday's methods of mining. Some of you probably had first-hand experience with some of these so you know they were tedious, time-consuming and involved a lot of heavy labour.Taking the Anaconda Company operations at Butte as an example, we can see what has happened in just the past ten years. In August of 1956, the Butte mines had 5,516 day's-pay employees and 976 salaried employees, for a total payroll of 6,492. In August of this year, there were 3,645 day's-pay employees and 605 on the salaried roll, for a total of 4,250. The number of contract miners had gone from 1,347 in 1956 to 606 in 1966 and that of other underground miners from 2,893 ten years ago to 1,149 this year. Along with these changes, however, another change of special significance has taken place, and that is in the number of skilled craftsmen, surface engineers and so on required for our operations. In 1966, we had 1,890 of these people, 600 more than in 1956 and nearly three times as many as just twenty years ago."

Jan 1, 1967

By G. A. Gross

Nearly 90 per cent of the iron ore produced in Canada is derived from iron-formation or bedded iron deposits. About 70 per cent of this consists of concentrates obtained fom iron-formation; another 20 per cent was formed by natural enrichment processes. Four principal varieties of iron-formation are recognized -the Algoma, Superior, Clinton and Minette types. Differences in their geology, mineralogy, chemical composition and environment of deposition are of special significance in their evaluation as ore.

Feb 1, 1966