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By J G. Brady

This paper discusses the ceramic products used in the construction industry in Canada, as well as the main raw materials used in their manufacture. The products include the! following: (1) clay prorlucts -such as facing brick (glazed and unglazed), common brick, facing tile (glazed and un-glazed), terra cotta, load-bearing tile, non-load-bearing tile, structural clay floor tile, quarry tile, drain tile, sew-er pipe, conduits .and flue liners -which are made mainly from domes-tic common clays and shales and from domestic or imported stoneware clays and low-grade fire clays; (2) floor and wall tiles of the whiteware type, which are produced from ingredients such as kaolin, ball clay, feldspar, nepheline syenite, talc, pvro-phyllite and wollastonite; (3) glass products -the major ones being sheet glass, plate glass and mineral wool (glass wool, and rock or slag wool) -which are made from such materials as silica sand, soda ash, salt cake, feldsspar, nepheline syenite, dolomitic limestone, high-calcium limestone. borax and (for rock and slag wool) various rocks or slags;

Jan 1, 1963

By E. Lee Cameron

Summary Records of the past show that the first mineral production in what is now the Province of Manitoba consisted of salt, obtained about the year 1800 by the evaporation of brine. Also at an early time in our history, the Ordovician limestone at St. Andrews Locks, East Selkirk, and other localities was quarried for use as building scone in the construction of forts and fur trading posts. Both salt and building stone are still produced in Manitoba, although not from the original sources. In addition, there is now a substantial production of a variety of other industrial minerals and their products such as lime, crushed stone, gypsum, peat moss, and bentonite. The annual dollar value of production of the industrial mineral industry in Manitoba is today greater than at any time in our past and is derived from a greater variety of products. At the present time, exclusive of the various gravel pits operated by the Provincial Department of Public Works, twenty companies operating thirty-four separate pits, quarries, or mines are producing industrial mineral raw materials in Manitoba. This paper attempts to outline the development of the industry from its start about 1800 to the present, giving general information on the various materials produced. Some suggestions regarding the possibilities of establishing new industries based on other raw materials are given at the end of the paper.

Jan 1, 1949

By D. J. Hains

IN this paper we shall examine the Why, Where and How concerning the agglomeration of iron ores and concentrates. Fig. l answers the questions @f why there is so much interest at the present time in the art of agglomeration. The use of sinter or pellets in the blast furnace has materially increased their rated •capacity. ':'President Hains Company Ltd. Engineering J. S. McMahon ( 1) reports an increase from 653 tons of .pig iron per day to 1140 tons of pig iron per day with the use of a 100 per cent sinter burden on one of his blast furnaces. In the United States the use of 100 per cent pellets has increased pig iron production from approximately 1800 tons per day to over 3000 tons pig iron per day (2). In our economic system the general objective is to produce more and better commodities cheaper. Fig. 2 shows the decrease in coke consumption with increased tonnages from the furnaces when using -

Jan 1, 1961

By H. A. Halupka, I. A. Mozer

"At its plant in San Juan, Peru, Marcona Mining Company operates two grate pelletizing furnaces for the agglomeration of 3.5 million long tons of magnetic concentrates annually. Line One, installed in 1963, was built by Lurgi as a downdraft process furnace utilizing a furnace fan for the recuperation of hot gases from the cooling zone. This line was modified in 1966 to include both updraft drying and downdraft drying, and the original roof burners were converted to side-wall burners. Line Two, a Dravo-Lurgi furnace with an annual capacity of 2.4 million long tons, was built in 1966. This line, in contrast to the modified Lurgi furnace, employs direct recuperation of hot gases from the cooling zone and utilization of process gases from the firing zone for updraft drying.At its plant in San Juan, Peru, Marcona Mining Compa-ny operates two grate pelletizing furnaces for the agglo-meration of 3.5 million long tons of magnetic concentrates annually. Line One, installed in 1963, was built by Lurgi as a downdraft process furnace utilizing a furnace fan for the recuperation of hot gases from the cooling zone. This line was modified in 1966 to include both updraft drying and downdraft drying, and the original roof burners were converted to side-wall burners. Line Two, a Dravo-Lurgi furnace with an annual capacity of 2.4 million long tons, was built in 1966. This line, in contrast to the modified Lurgi furnace, employs direct recuperation of hot gases from the cooling zone and utilization of process gases from the firing zone for updraft drying. 5 per cent increased capacity, 30 per cent lower fuel oil consumption, and approximately 400 per cent reduction in grate bar and pallet corrosion. Firing of the pellet bed was improved by conversion from roof to side-wall burners. This modification also permitted utilization of monolithic refractory in place of pre-fired shapes, thereby improving over-all furnace availability and reducing refractory stock requirements from 154 different shapes to 18.Data are presented to compare operating performance of the Dravo-Lurgi furnace and the modified Lurgi furnace. These data show 30 per cent lower fuel oil consumption and 10 per cent higher capacity per unit grate area for the Dravo-Lurgi furnace, which also averages higher availability due to greater operating flexibility."

Jan 1, 1970

By D. B. Stewart

In the past few years, much effort has been spent in elucidating the impact of diesel engines on the mine environment. This paper summarizes diesel fundamentals , exhaust emissions and typical tailpipe concentrations. Mine sampling results and an evaluation of exhaust treatment systems are discussed. A review of changes in pollutant concentrations between the tailpipe and the mine exit is made and suggestions are given to reduce operator exposure to diesel contaminants.

Jan 1, 1978

By G. Armand, G. Arnold, A. Giraud, C. Auvray

The knowledge and understanding of the mechanical behavior of claystone is of critical importance in the aim of nuclear wastes storage. In this study, specimens of Callovo-Oxfordian claystone (COx) have been obtained from the ANDRA underground research laboratory in Meuse/Haute-Marne (France). This claystone is composed of carbonate inclusions (10-50µm) embedded in an argillaceous matrix (representing expanding clay minerals, such as smectites). The matrix itself is also multiphase and composed of clay aggregates of 1µm-size carbonate and quartz inclusions. This multiphase microstructure leads to a high heterogeneity witch was analysed through nanoindentation test grids. Moreover, the mechanical behavior of the claystone matrix is highly sensitive to humidity and temperature. The nanoindentation tests were performed in a climatic (i.e. temperature and humidity controlled) chamber at relative humidity levels from 50% to 98% and at two temperatures: 20°C and 60°C. In a first step, the curves of indentation were analysed using the commonly used Oliver and Pharr’s approach. Other wellknown parameters as the creep factor were also extracted. In a second step, Fisher-Cripps model (Fischer- Cripps, 2004) and Vandamme and Ulm model (Vandamme & Ulm, 2006) were used to identify viscoelastic properties. A statistical analysis is used in order to extract mechanical characteristics of the different phases. Hardness and elastic modulus decrease drastically with saturation (above 80% humidity) and to a lesser extend with temperature.

Jan 1, 2015

By Pierre Pelletier, Christian Pichetie, Dany Pelletier

"IntroductionDuring 1994, Barrick Gold Corporation, or American Barrick at that period, acquired Lac Minerals Ltd. properties. One of them was the Bousquet Complex. The Bousquet Complex is divided into three distinct sites: one mine (Bousquet 2), one mill (Est-Malartic Division) and one analytical chemistry laboratory (Les Terrains auriferes).The Bousquet 2 orebody was discovered in 1986. An extensive drilling program was initiated during 1987. Its purpose was to define the orebody extent. At the end of 1997, gold production from Bousquet 2 mine reached 1 290 000 oz of gold from a cumulative tonnage processed of 4 175 000 M t.From 1980 to 1990, the Est-Malartic mill was used for the treatment of ore from the following mines: Bousquet 1, Doyon, Francoeur (Richmont mines), Buckshot and 1-20 stope. At present, the mill receives ore from the Bousquet 2 mine.HistoryThe Est-Malartic mill is located close to the town of Malartic in northwestern Quebec. The mill has been in production since the mid-1930s processing mainly clean, free mill gold ore. Active mining from the Est-Malartic mine ceased in 1979 and the mill was switched to custom processing of ore from La Mine Doyon located some 45 km to the west. This custom processing arrangement continued until 1987 when the expanded mill at Doyon became available to process all of the Doyon production. In 1987, Lac Minerals commenced development of a second mine at the Bousquet site located 40 km west of Malartic. This mine, Bousquet 2, is the down dip extension of the La Ronde mine developed by Agnico Eagle. During pre-feasibility evaluations, it was determined that it would be economically more attractive to modify the existing Est-Malartic mill than building a new facility on site. The Est-Malartic mill modifications for processing the high-copper/gold ore from the Bousquet 2 mine began in late 1989 and new circuits were commissioned in mid-1990. Modifications included the addition of both gravity and flotation concentration circuits to recover coarse, free gold and the copper. The existing leaching circuit continued to operate on the copper flotation tailings with some minor modifications to the solution handling systems. A S02/Air cyanide destruction circuit was also added at that time."

Jan 1, 2000

By W. A. Lang

Introduction In this review, which is the fifth of the series on the Progress in Coal Technology, an attempt has been made to outline some of the more important developments that have taken place in coal carbonization during the last decade. Research into both high-and low-temperature carbonization has been active for three principal reasons: (1) the growing shortages in most countries of high-quality coking coals; (2) the demand for smokeless fuels for domestic purposes; (3) the need for metallurgical coke for the increased output of steel in the post-war years. The growing importance of coal tars as a source of chemicals for the preparation of synthetic products and of coal gases for the recovery of sulphur is evident. Many of the researches initiated because of wartime necessity have been continued .and even expanded in the post-war years. High-temperature carbonization with a suitable coal yields a strong coke which is used primarily for metallurgical purposes, a tar with good marketable value, and a large yield of gas of medium calorific value. Low-temperature carbonization gives a more free-burning solid product suitable for a domestic fuel, a high yield of a tar which is generally regarded as superior to high-temperature tar for chemical purposes, and a smaller yield of a higher-heat-value gas.

Jan 1, 1951

By K. Winterton, Carruthers. J.

"Attempts have been made to produce hardened structures of a pseudomorphic type in various carbon and alloy steels. In order to obtain martensite with a fine distribution of cementite, an initial structure of fine lamellar or nodular pearlite is required; this may be obtained by conventional means. This is followed by partial austenitization and quenching.Two methods have been tried to induce partial austenitization:(a) A resistance (direct current) heating method involving rapid entry into the austenite field.(b) A new method, described as the ""threshold"" technique, involving homogenization of temperature just below A 1, followed by entry into the austenite field; two furnaces are required.The resulting structures have been examined for microstructures, hardness, tensile, and impact values. The tensile properties are comparable with those obtainable by conventional treatment methods. Impact values are disappointing, but this is explainable from the nature of the manifold changes occurring."

Jan 1, 1960

By J. E. Gillespie

Introduction Mineral wool may be defined as "rock, slag, or glass fibres made by a process of melting and blowing by steam or air, containing a minimum of oil and unfiberized material" (U.S. Bureau of Standards CS 117-44). The earliest production of the material was in Wales, about one hundred years ago. In the United States, the industry daces from 1870 when a plant, using slag as raw material, was established in Greenfield, New Jersey. It was not until 1897, however, that large-scale production was commenced on this continent at a plant in Alexandria, Indiana, which utilized rock from nearby deposits. Today, mineral wool is manufactured in many parts of the United States and Canada, the plants for the most part being in close proximity to deposits of suitable rock or to sources of slag. In the United States there are some seventy-five producers with a total annual capacity of nearly one million tons of wool. In Canada, in 1946, eleven manufacturers produced about fifty million square feet of batt-type mineral wool insulation material. Mineral wool is, perhaps, the most efficient of all heat-insulating materials and, moreover, it is fireproof, extremely durable, and insect- proof. Its high efficiency is due to the very low thermal conductivity of the fibres themselves and to the fact that the produce as marketed contains up to 90 per cent non-conducting air space. Depending on the degree of compression of the fibres in the manufactured product, the specific gravity ranges from 2 lb. to 10 lb. per cubic foot. Products Marketed Following are the principal forms in which mineral wool is marketed: Blanket. - Mineral wool with or without reinforcing on one or both sides, with various types of confining media, all suitably bound together.

Jan 1, 1948

By G. G. Bowser

THE time has come when, as your President, 1 turn the helm over to my worthy successor. When 1 was reminded by our Secretary that 1 had to prepare an address for this meeting, 1 was at a loss for a subject. In the hope of inspiration 1 perused the records of our Society for some years past. 1 found in these records that many problems in need of solution relative to industry in Nova Scotia were discursively dealt with and that sound thought was given to the solution of these problems, with a natural leaning, of course, to problems pertaining to the mining industry. 1 found also that some of the reasoning was remarkably prophetie. Some of these subjects and problems were: The use of pulverized coal to generate power instead of hydro-electric power; rural electrification; the importance of youth training for an efficient place in industry; the proper marketing of coal; the fuels competing with coal; the need for better in-dustrial relations between employer and employee; better education for success in the social field as applied to industry; and Canadian unity. The issue of some of these copies has been forced upon us by war. For instance, there appears to be no marketing problem for coal, nor does there ? seem to be a marketing problem for anything just at present. The problem of the coal producer just now is supply and transportation. Also, at present, coal fe.ars no competitors, such as oil-and not even hardwood. Many large companies now have an industrial Relations or Personnel Manager and department. Furthermore, we have been compelled of necessity to train our young men, and women also, for both industry and war. However, war does not solve these problems and, with the return to normal times, we may be faced with the same troubles in even greater measure. My reason for mentioning these copies is to point out that, as mining men, we are aU desirous of progress in every industry, not only the mining industry; and that mining men are able to see clearly ahead. In normal times, especially in matters not directly affecting the mining industry, we are inclined to let matters take their own good rime, or let the government do it. We do not seem to realize that these necessary and desirable changes can be made in times of peace-instead of being forced upon us by war or other social upheavals-by the method of sound thought and action to the desired end.

Jan 1, 1943

By C. E. Baltzer, W. H. Harper

"This study has been developed to illustrate the trend and pattern of distribution applying to the quantities and costs of the fossil fuels used, and the related amounts of electricity generated, in the thermal segment of the Canadian electric utility industry.Traditionally, Canada's requirements for electric energy have been preponderantly met by hydraulic power. The need for augmented supplies of thermally generated power has mainly developed since the close of World War Il-in an era that has seen drastic decline in the production of indigenous coal and buoyant expansion in the supply of oil and natural gas. Although coal currently is faced with serious competition from the fluid fuels, the utility industry in particular promises an advancing market for coal, because of its abundant resource, at prices less likely to show sharp increase. For Canada as a whole, this trend has been progressive since 1959, and, unbelievable as it may now seem, the extent of the advance by 1975, particularly in Ontario and the Prairie Provinces, may well be as much, or even more, than the present rate of consumption for all purposes.The text and the tables and charts are arranged to focus attention on: the growth of thermal genera ting capability; the historical trend in consumption of fuel and the related production of electricity; patterns of distribution by types of fuel and thermal capacity; the relationship of steam to other sources of thermal capacity; and the quantities, costs and related percentages of electricity generated by types and kinds of fuel used, both regionally and provincially."

Jan 1, 1966

By M. Nusheh, C. Bumby, A-H. Puichaud

"Vanadium-bearing titanomagnetite ironsand deposits occur along a 480 km stretch of the west coast of New Zealand. In the present study, the leaching behaviour of NZ ironsand was investigated in hydrochloric acid (2–10 M) solution at 50–80°C for 2 h. The resulting leaching liquors exhibited Fe/V ratios in the range 150–180. The distribution of trace element contaminants between solution and solid residue was investigated, and processing conditions have been determined for rapid and efficient dissolution of Fe, Ti and V into the leaching solution. In addition, mineralogical analysis of raw ironsand and leached residues was performed in order to study the leaching mechanism. Samples were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy (EDX), X-ray fluorescence spectroscopy, qualitative and quantitative X-ray diffraction and inductively coupled plasma mass spectrometry (ICP). Results indicate that the dominant dissolution process follows shrinking particle mechanism. However, ironsand particles containing ex-solution lamellae exhibited a different leaching behaviour compared to homogenous titanomagnetite particles.INTRODUCTION Titanomagnetite ironsand (blacksand) forms Quaternary onshore beach and dune deposits and offshore marine deposits (Figure 1) along 480 km of coastline from Kaipara Harbour south to Wanganui on the west coast of the North Island (Christie, 2016). It attracted the attention of scientists from the earliest times (Galbreath, 1998). The principal minerals in ironsand are titanomagnetite (TTM), ilmenite, quartz and ferromagnesian minerals such as augite, hornblende, diopside, and olivine with smaller amounts of rutile and apatite (Mauk, 2016).Several large ironsand deposits have been discovered and exploited since the late 1960’s. The Waikato North Head and Taharoa mines are currently operating and they have a 2015 measured resource of 400 million tonnes in total and provide over 2 million tonnes of concentrate per year by simple cost effective magnetic separation process (Christie, 2016; Christie & Brathwaite, 1997). The concentrate contains not only 7–8% TiO2 and 56–60% SFe, but also 0.3–0.6% V2O5, is both a valuable titanium mineral and a source of vanadium. All the production is used for steelmaking industries. The other potential for utilizing more of this resource without requirement of integration into an iron and steel producing plant is to develop a hydrometallurgical route with advantages of higher efficiency along with lower emissions. Currently, there is no existing commercial process capable of extracting all three of these elements as industrial-grade commodity products. Acid leaching of TTM concentrate with higher degrees of recovery and selectivity is a key step in any possible hydrometallurgical route."

Jan 1, 2017

By Norman B. Davis

Introductory Feldspar is one of the most important mineral products consumed by the various branches of the ceramic industry. In the manufacture of table ware, electric porcelain, floor tile, and enamels, it supplies the chief fluxing ingredients necessary to bond the other more or less inert materials together when moulded into desired shape and fired in a kiln. Feldspar is used in the manufacture of bottle glass as a means of introducing alumina in a form easily assimilated. It is also used in certain scouring soaps particularly designed for cleaning enamel and glass surfaces. Feldspar, as it finds its way to the trade, is not a single mineral but is rather a mixture of various proportions of the feldspar silicate series, either in natural intergrowth or blended in the milling process, to produce a desired result. It is often further modified by the presence of quartz in amounts up to 30 per cent. The table on the next page gives typical commercial analyses of feldspar from various sources. Canadian feldspar produced to date has consisted mainly of the high-potash, relatively low-soda, variety, and has enjoyed a good market in the United States for the manufacture of enamels, electric porcelain, and vitrified table-ware. About eighty per cent of the output has been exported to the United States, but, with increased milling facilities in Canada and changes taking place in domestic United States sources of supply, the proportion exported will be reduced next year.

Jan 1, 1931

By J. A. Brothers, M. R. Foran

"AbstractThis paper reviews the progress made in the manufacture of hydraulic cement from iron blast-furnace slag by simply grinding the granulated material with other constituents. The influence of the chemical and mineralogical composition of the slag, the conditions of granulation, the manner of drying, and the fineness of grinding, on the hydraulic properties of the cement, is discussed. The effect of additions of lime, portland cement, and anhydrite, alone and in combination, on the physical and cementing qualities of the mortar and concrete made from Sydney blast furnace slag, is shown in tables of data and is reviewed in some de- tail. The work at the Nova Scotia Technical College has shown that a cement equivalent in every respect to portland cement can be made from basic blast furnace slag- by the us2 of certain quantities of portland cement as an activator.IntroductionBlast furnace slag is a potentially valuable material for the manufacture of hydraulic cement. It is a by-product of the manufacture of iron in the blast furnace, and is formed by the combination of the silica and alumina .of the iron ore with the limestone flux. The metallurgist terms a slag .acid or •basic according as the percentage of lime is less or greater than the percentage of silica plus alumina. The basic slags have the •more pronounced hydraulic properties."

Jan 1, 1950

By A. Becker, C. Gauvreau, L. S. Collett

"A scale model was designed to simulate the airborne Barringer INPUT time domain electromagnetic system. The amplitude of the response to a vertical conductive dyke varies considerably with the conductor's thickness conductivity product (TCP). The response increases from a minimum detectable level at a TCP of about 2 mhos, rises to its maximum value at a dyke TCP of 15 mhos and then falls again so that conductors with a TCP exceeding 500 mhos would probably remain undetected. Measurements made with both standard receiver coil configurations (maximum or minimum coupled) indicate comparable effectiveness for both systems, either from the viewpoint of vertical conductor detection or from the viewpoint of discrimination against overburden anomalies."

Jan 1, 1972

By V. S. Papezik

Pyrophyllite, an AI silicate used in the production of ceramic materials, is formed mainly by alteration of felsic to intermediate volcanic rocks, either directly (at temperatures of 250-300°C and pressures of 1-2 kbar) or by subsequent low-grade metamorphism of aluminous protoliths produced by thermal fluids or even by prolonged weathering. Most pyrophyllite deposits in North America are concentrated in a belt of Late Precambrian volcanic and sedimentary rocks, the "Avalon Zone ", which extends along the eastern flank of the Appalachian mountain system from Newfoundland to the southeastern U.S.A. The only producing pyrophyllite mine in Canada is an open pit located near the settlement of Foxtrap on the Avalon Peninsula of Newfoundland. It lies in a belt of rhyolitic flows and pyroclastics intruded by a granitoid pluton. The rocks have been leached along a shear- or fracture zone, depleted in silica, alkalies, Ca, Mg and Fe by the action of hydrothermal fluids, and recrystallized to a very fine-grained massive assemblage of pyrophyllite, muscovite ("sericite") and quartz. High-grade pyrophyllite lenses contain small nodules of diaspore with minor barite; rutile is present in trace amounts. The close proximity of all pyrophyllitized zones on the peninsula to the granite contact suggests that the alteration was produced by thermal fluids genetically connected with the granitoid pluton. The fine-grained pyrophyllite-bearing rocks, with their simple mineralogy, are suitable for quantitative modal analysis by X-ray diffraction. Chemically analyzed samples from the alteration zone were used for the construction of working curves by plotting calculated mineral content against the intensity of selected diffraction peaks. The accuracy of the resulting curves is ±4.5% for quartz, ±3.6% for pyrophyllite and ±2.7% for muscovite. Pelletized samples give best results. The XRD method is suitable for a rapid analysis of a large number of grab or core samples to outline higher-grade areas for more detailed sampling.

Jan 1, 1978

By G. E. Norman, A. L. Mckague

"The new smelting process commenced operation in 1978. The pelletizing and sinter plants were replaced with slurry-fed roasters and the blast furnaces with electric furnaces. The existing converter aisle and matte handling facilities remained unchanged.Process DescriptionNickel-copper concentrate is partially roasted in two slurry-fed fluid bed roasters. After gas cleaning, the sulphur dioxide gas is transferred to the acid plant. The roaster product is conveyed to two electric furnaces for smelting to produce a waste slag and furnace matte. The slag goes to the disposal area and furnace matte containing the metal values is processed in the converters for further removal of iron and sulphur.The final matte containing about 75 per cent metal values is shipped to the refinery in Norway.The commercial smelter was designed for 2135 tonnes per day of concentrate, with an availability of 85% . Roasters and electric furnaces were sized at 117 per cent of design, or 1250 tonnes per day on each of two lines. Concentrate storage capacity in the plant is sufficient for two to three days' plant operation.The new smelting process will be discussed under the following headings:Concentrate Slurry HandlingFeed PreparationRoaster OperationRoaster Gas CleaningCalcine TransferElectric Furnace Operation and Process Control Converting and Matte HandlingUnder these headings, process control , equipment changes, and plant performance after three years' operation is reviewed. A brief discussion of accident prevention , and working environment is also included ."

Jan 1, 1984

By O. A. Carson

"IntroductionTHE ZINC-BASE die casting alloys in common usage contain approximately 4 per cent aluminum as the major alloy element. In addition, they contain about 0.05 per cent Mg .and may• have a small amount .of copper. These are usually the only •elements intentionally present.Small amounts of some impurities have been shown to have a deleterious effect on the properties of these alloys and therefore the impurities are kept low by starting with '99.99%' zinc.The reasons for holding the aluminum content at 4 per cent are not clear. Some statements appear in the literature that higher aluminum increases the brittleness, but probably the chief reason was the relative price of zinc and of aluminum when 4% alloys became firmly established. At that time, aluminum was three to four times the price •of zinc on a weight •basis. Recent prices, roughly equivalent per lb., make aluminum considerably cheaper than zinc on a volume basis and suggest that increased aluminum content would result in a decrease in the cost per piece due to the lower density of the alloy.Little information could be found in the literature and, therefore, it was decided to determine some physical properties of the higher aluminum zinc-base alloys made from high-purity zinc."

Jan 1, 1953

By W. S. Dyer

Introduction In northern Ontario, refractory clay is found on four rivers of the James Bay watershed: the Abitibi, the Mattagami, the Missinaibi, and the Moose. The clay all belongs to the same geological formation ( the Mattagami of Lower Cretaceous age) , and occurs within a structural depression or 'basin', the boundaries of which have never been defined but which appears to cover at least 1,500 square miles of territory. The recently constructed James Bay extension of the Temiskaming and Northern Ontario railway crosses the northeast end of the basin at the Onakawana lignite field, which by rail is 126 miles north of Cochrane, 605 miles north of Toronto, and 60 miles southwest of Moose Factory. Smoky Falls, the northern terminus of the railway owned by the Spruce Falls Power & Paper Company, Limited, is 7 miles south of one other point in the basin, i.e., the outcrops of refractory clay, sand, and kaolin at the foot of Long rapids on the Mattagami river. Smoky Falls is 50 miles north of Kapuskasing. In a very early report(l) , Dr. Robert Bell, of the Geological Survey of Canada, described '"light coloured marl in horizontal beds" from the Missinaibi river, and noted that the lignite also occurring in the river was probably :associated with the marls. This was undoubtedly the Cretaceous refractory day. Other early writers noted the occurrence of fire-clays, but it was not until Joseph Keele(2), of the Geological Survey, visited thee region in 1919 and studied the clays that their real significance was known.

Jan 1, 1933