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By Brandt Porter, Lawrence K. Nordell, Alexander Potapor

"Improving comminution efficiencies with better machine geometries and motions, improved nip angles, rock movement control, and voids regulation among rocks are some of the next steps to better machine performance. Recent gains (~30%) using high pressure grinding rolls (HPGRS) and vertical roller mills, in theory and practice, are based on Prof. Klaus Schönert’s academic studies (1979–1996) on rock breakage physics. More recently, University of British Columbia Prof. Bern Klein’s studies (2006–present) via the Ph.D. thesis of Z. Davaanyam (2015) further validate theory with practice from laboratory measurements used in this paper.They demonstrated ideal rock compression breakage, within HPGR and vertical roller mill machines using a piston-die apparatus. Similar rock size range is used. The piston-die confine rock breakage behavior. However, these studies do not extend to larger rocks (> 75 mm), and do not demonstrate the influence of rock voids among bifurcation of rocks during comminution. Further, machines fed with larger rock sizes, such as gyratory, jaw, and cone crushers, are not designed or evaluated for geometry nip angle efficiency.Herein we illustrate a performance gain of a new comminution machine, the conjugate anvil-hammer mill (CAHM), first presented at SAG 2011 (Nordell, 2012). The CAHM machine digests rock sizes 400% larger than HPGR, improves rock grip/nip geometry, better improves rock voids, improves surface wear life > 500%, and improves rock containment and slippage during compression. In all, the CAHM machine shows 22 potential improvements over the HPGR. Most importantly, CAHM shows a 50% kWh/ton improvement compared to the HPGR. Our studies use an advanced Discrete Element Method (DEM) computer program called ROCKY. ROCKY simulates moving boundaries, surface wear mechanics, and incorporates rock breakage physics based on the fundamentals of JKMRC T10 protocol [×] with tuned A × b breakage parameters.We calibrate rock breakage in our DEM code to mimicking both UBC laboratory piston-die and HPGR comminution measurements. We then model CAHM with these known ore and machine properties. Differences are illustrated using DEM techniques on each machine, including key points of when each: use geometry; initiate bifurcation breakage; provide a map of particle size distribution by location; illustrate the importance of controlling voids to minimize agglomeration after breakage; machine performance limits; and kWh/ton benefit."

Jan 1, 2016

By A. D. Pittuck

Refractory minerals .containing uranium and columbium have been successfully treated at Queen's University, Kingston, to produce high-grade concentrates. Recoveries of over 90 per cent of the uranium and columbium have been obtained when treating concentrates containing euxenite, fergusonite, betafite, and pyrochlore. The processes ?consisted -of leaching the columbium with hydrofluoric acid, and the uranium with nitric acid, sulphuric acid, or sodium carbonate solutions. The leach liquors were extracted with organic solvents from which the values were stripped and precipitated, producing final products assaying 45 to 55 per cent Ob2O5 and 60 to 70 per cent U3Os.

Jan 1, 1958

By G. W. Neumann, J. R. Schnarr

The lead-zinc-copper-silver ores mined by Brunswick Mining and Smelting Corporation Limited at their No. 12 underground mine and No. 6 open-pit operation, and treated by distinct concentration processes in separate plants, present difficult metallurgical problems because of the extremely fine dissemination of the valuable minerals with pyrite and pyrrhotite. The problem of concentration is further complicated, in the No. 12 ore, by the presence of a varying content of graphitic carbon. This paper describes the milling of No. 12 ore and the production of copper, lead and zinc concentrates by differential flotation.

Jan 1, 1971

By A. Bauer, P. Katsabanis, M. Baker

The principal results from a previous paper presented at the Mine Accident Prevention Association of Ontario in 1987 (1) are summarized here. It is concluded that the selection of explosives in mines experiencing sulphide ignitions is important and that aluminized explosives should be avoided because of their high explosion temperatures and their detonation products. The duration of the blast is also critical and secondary blasts should not occur simultaneously with nearby priroa:ty blasts.

May 11, 1988

By B. Konda, R. Lauer, D. Camilucci, D. Gladwin

"Income based taxes are significant cost elements to be considered in evaluating investment in new mine development. This paper presents the results of comparative analysis of effective income-based tax rates for mining in the Northwest Territories (NWT), selected Canadian provinces and international jurisdictions. The study was done as background to a review of royalty regulations for the NWT. ObjectiveThis paper presents results of comparative analysis of effective mining royalty1 rates, and combined effective mining royalty and income tax rates on selected mine models for the Northwest Territories (NWT), with those for several other jurisdictions in Canada and abroad which compete with the NWT for mining investment.BackgroundThe February 27, 1995 federal budget directed the Department of Indian Affairs and Northern Development (DIAND) to proceed with a comprehensive review and amendments to northern natural resource management legislation in order “to increase revenues and ensure a fair return to the Crown.” DIAND is responsible for the administration of the Territorial Lands Act, and its regulations.The Territorial Lands Act gives the Governor-in-Council the authority to “… make regulations for the leasing of mining rights in, under or on territorial lands and the payment of royalties therefor,…”. In the NWT, the Canada Mining Regulations (CMR) provide for the disposition of mineral rights for most minerals, other than coal, petroleum and related hydrocarbons, in return for the payment of a royalty to the Crown.As part of this review of the NWT mining royalty regime, several computer mine models were developed and tax regimes in a number of jurisdictions were analyzed. Effective mining royalty rates, and the combined effective mining royalty and income tax rates were compared across the jurisdictions. The results presented in this paper are a part of the background work done in preparing a discussion paper on proposed changes to the NWT mining royalty that is expected to be released for public consultation in the very near future."

Jan 1, 1997

By John E. Callahan

"A stream sediment geochemical survey covering an area of 13.000 sq. km near Churchill Falls. Labrador. was conducted for Brinex (British Newfoundland Explorations Ltd.) prior to partial flooding by the Churchill Falls power project. Stream sediments (minus 80-mesh) were analyzed for Cu, Pb, Zn, Ni, Ag, Mo. U and Mn, and the heavy mineral, nonmagnetic fraction (minus 60-mesh) for Cu, Pb, Zn, Ni, Ag, Mo, Ba and Mn. A binocular examination of the concentrates for sulphides and pyrope garnet was done on the heavy mineral concentrates. The concentrates were also examined for fluorescent minerals.Two distinct areas with high trace-element values indicate the need for follow-up studies. The first is in an area of gabbro erratics containing massive and disseminated sulphides (pyrrhotite, pyrite and minor chalcopyrite) on the western edge of the survey area along the Esker Road. The second, largest area (several hundred square kilometres) is anomalous in U and Mo and associated with felsic intrusives (Red Wine Complex?), syenites. granite gneiss and sedimentary rocks (Seal Lake Group?).The binocular study showed that almost 15% of the heavy mineral concentrates contained pyrite and no other sulphides. This indicates that this technique may be worthwhile in determining the presence of sulphide minerals in stream sediments from glaciated environments. The only fluorescent mineral observed in the study was zircon."

Jan 1, 1981

By X. S. Yuan

With the production increase of Oil Sand in Fort McMurray Alberta, more efficient tailings disposal has become a priority for Syncrude Canada Ltd. A lot of work on tailings research and development has been compiled to determine the most effective deposition to increase reclamation options, water re-use and thermal energy recovery. Efficient flocculation of fine oil sand tailings is the key technology for thickening. It was identified that flocculation of fine transition/marine ore tailings using a single flocculant was not effective. The thickener overflow contains 1-4% solids content compared with the target solids content of <0.5% obtained with Estuarine ore. As a result, novel processes for treatment of fine transition/marine ore tailings have been developed at Syncrude Bitumen Production Development since June 2004. While the conventional processes using a single flocculant, a single coagulation, or a coagulant-flocculant combination was ineffective for transition and marine ore tailings, the new processes including Coagulation-Flocculation-Coagulation (CFC), Flocculation-Coagulation (FC) and Flocculation-Coagulation-Flocculation (FCF) were acceptable options. The key components of these technologies consist of the recipe of chemicals and their adding sequence. With these technologies, almost all sub-micron clay minerals are aggregated together and settle as a whole, resulting in a clear supernatant of less than 0.1% solids.

Jan 1, 2006

By D. G. Sinclair

IN surveying the changes that have taken place in the mining industry of Ontario in the past ten years, the striking growth of the gold mining industry first attracts attention. In 1925 there were only twelve regularly producing gold mines in the Province, six of which were located in the Porcupine area, four at Kirkland Lake, and one each at Larder Lake and Boston Creek. In contrast with this, the year that has just closed (1935) has seen production on a steady basis from forty mines, with what may be termed spasmodic production from twelve other properties. This so-called spasmodic production is, however, responsible for the recovery of gold to an estimated value of between $75,000 and $100,000 during the year. Further illustrating the expansion in the gold mining group is the activity in the exploration and development of properties. In 1925, mining operations were conducted at 29 properties which had not reached production, while in 1935 work of this nature was carried on at 87 such properties. It is of interest to note that of the six properties listed as producers in Porcupine ten years ago, five are still producing at rates considerably in excess of the tonnages handled at that time. In fact, the estimated tonnage treated at these mines in 1935 exceeds the 1925 tonnage by approximately half a million tons. In Kirkland Lake, the figures are still more striking. The four mines in production in that camp in 1925 milled 346,584 tons, producing bullion to the value of $5,132,128, while in 1935 these same mines treated approximately 1,643,000 tons, with a recovery of roughly $29,300,000. While Porcupine and Kirkland Lake remain the great gold-producing camps of the Province, the growing importance of the newer areas is readily appreciated when we consider that in 1935 the mills of these areas treated over 1,000,000 tons of ore for a production in excess of $7,500,000. Pro-duction from these newer districts first became of importance in 1930 with the commencement of recovery at the Howey mine, in Red Lake, and the Minto, in Michipicoten. Since 1930, eighteen new gold mills have gone into production in the Red Lake, Little Long Lac-Beardmore, Pickle Crow, Sturgeon Lake, Michipicoten, Sudbury, and Matachewan areas. In respect to silver mining, the period under review has seen a considerable slackening of activity, due to a generally unstable and depreciated price for the product and to the exhaustion of ore reserves in the mines.

Jan 1, 1936

By Fred C. Bond

A study of the settling and thickening of finely divided pulps was undertaken with the object of obtaining certain fundamental relationships, with resulting improvements in the design and operation of mechanical equipment. The subject has been treated in two parts: testing and batch thickening, and continuous thickening, including calculations of capacity and dimensions. Part 1. ? Testing and Batch Thickening The usual method of making thickening tests is to agitate the pulp with a plunger in a graduated glass cylinder and let it settle, while recording the time rate of settling. The settling rates corresponding to different pulp dilutions are found, the ultimate dilution obtained is measured, and the necessary thickener area in square feet per ton of dry solids per 24 hours is calculated, for each pulp dilution. The largest area found is used in selecting the proper thickener size.

Jan 1, 1946

By A. I. Collins, D. Danninger

Newmont has installed advanced control and online optimization on the dry grinding circuit and both roasters on its Carlin Trend refractory ore treatment plant. Subsequently, Newmont has developed a master plan for institutionalizing advanced control and optimization on all its processing units. Newmont is committed to a program of applying advanced control and optimization from crushing of ore to pouring of gold. This paper describes Newmont&apos;s experience with implementing advanced control and optimization and the benefits received. In addition, identification of advanced control and optimization opportunities and their economic justification is discussed.

Jan 1, 2005

By Reis. E., P. Pino Véliz

"Along the process of defining the fundamentals of a ferronickel project, several questions require proper answers from the very beginning such as the size and characteristics of the laterite deposit (oxide or silicate), the mineralogical variability, and the selection of the most valuable process route. In general, these elements will be defined along the progress of the exploration and feasibility studies, and definitive engineering. Also, from the very preliminary estimates, three questions are very common: what should be the plant capacity (annual tonnes of contained nickel), what will be the probable capital required (CAPEX), and what will be the estimated timeline (schedule) between the initial stage, say the feasibility study and the plant start-up and ramp-up to designed capacity. The accuracy of the capital cost estimates also progresses along the different stages of development from ±50% at the Preliminary Economic Assessment (PEA) stage down to ±5% for the Detailed Engineering and Construction stage. These accuracies of estimates have been, in some ways, accepted by the mining community and investors. The industry accepted benchmark for ferronickel projects in terms of CAPEX are then in the order of US$50,000 per tonne of nickel contained in the FeNi product. In this paper, the authors analyze in some details three ferronickel projects for lateritic ores that have selected the Rotary Kiln - Electric Furnace (RKEF) as the suitable technological route and have started production in the period 2006–2016. Some key aspects of the ferronickel projects are examined: 1) size and type of deposit; 2) flowsheet selection; 3) evolution of capital cost as a function of capacity from the feasibility stage to construction; 4) comparison between planned production scale and actual ramp up; 5) estimated capital expenditure (CAPEX) compared with actual figures; 6) nickel price evolution and timing of the approval for the project to proceed to construction and production start-up. The objective of this paper is to identify key elements that should be addressed in future projects and that are proposed as benchmark figures for similar projects."

Jan 1, 2017

By Balmer Neilly

In these days of arrested prosperity, when patience is tried and the future but dimly outlined, Canada&apos;s gold mining industry stands out as a beacon light shedding its rays of hope and confidence and demonstrating that there is still one product unaffected by Customs barriers and eagerly sought by all the people of the world. Some other forms of industry have hesitated and side-stepped. Some have cried for help, and in spite of public assistance, generously extended, they are still unable to demonstrate definitely their ability to resume the onward march. But gold mining has never hesitated. As an industry, it has bad an unique experience. When prices are high and conditions are generally referred to as prosperous, this industry is adversely affected. The cost of production goes up; profits are diminished; public sympathy is lacking; and, thrown upon its own resources, the industry tightens up its belt and throws its whole energy into an effort to improve operating conditions, and offset high prices by increased efficiency. When, in due course, depression follows inflation and prices ebb, the gold miner, through necessity, finds himself physically and mentally prepared to meet the situation.

Jan 1, 1932

By Wignall. T. K., J. De Geoffroy

Statistical models are fitted to the observed distributions of eighteen characteristics of the population of commercial porphyry deposits of North and South America. The statistical base required for the formulation of the statistical models includes 58 commercial porphyry-copper-molybdenum deposits of the Cordilleran Belt from which geological, geometric and economic data were collected. Predictive and composite models are derived from the statistical study to assist explorat10n. planning, engineering studies and fmanc1al analyses as required for the development of new porphyry deposits in the Cordilleran Belt.

Jan 1, 1973

By Arthur B. Yates

"The nickel deposits of Sudbury, discovered in .1885, have probably commanded as much attention as any single group of orebodies in the world. They have been the major source of the world's nickel supply since 1903, when their production first surpassed that from the Pacific Island of New Caledonia. From 1903 to 1914 the production from New Caledonia remained essentially constant, whereas that from Sudbury increased from 13,000,000 to 50,000,000 pounds a year. After 1914 the production from New Caledonia gradually dropped to about 4,000,000 pounds in 1919, where it remained until 1923. During these years the Canadian production increased steadily and since 1923 has gone up at an amazing rate to a peak of over 280,000,000 pounds in 1941. Meanwhile the New Caledonia production increased to about 10,000,000 pounds until the pressure of war raised it to roughly 14,000,000 pounds a year.The Sudbury deposits, because they have been the source of 80 per cent of the world supply of nickel, because of their economic importance to the world of metals, and because they are geologically unique in their occurrence, structure, and genesis, have attracted foremost consideration and the literature relative to their geology is voluminous. This is particularly true in regard to genesis.There is a significant and interesting parallel in time between the advancement of the science of economic geology and the great expansion of the nickel industry. The controversies regarding the fundamental classification of orebodies into generalized types were in full swing during the height of the development and expansion of the great nickel mines, and the Sudbury deposits, being the most important and the only ones of the sulphide type extensively developed, have been the chief source of information in regard to this type. The observations and the conclusions drawn thereon from numerous studies of the various mines of the district have not only influenced, but are the essence of, this chapter of the science."

Jan 1, 1954

Eagle Plains Resources? Exploration in the Northern Cordillera ?Eagle Plains Resources Ltd. (EPL) is actively exploring for Zn-Pb deposits in the northern Cordillera in both carbonate-hosted and shale-hosted (sedex) environments. ?This presentation will review some of the significant carbonate-hosted Zn-Pb showings occurring in the Mackenzie Mountains, NWT and make limited comparisons with sedexdeposits in the adjacent Selwyn Basin.

May 1, 2006

By W. A. Lang

RESEARCH has been defined as the link between the present and the future. Science, wonderful though its achievements may be, has but scratched the surface of the unknown. Research is directing its attention to winning new facts in order that their application to the processes of today may open up new sources of wealth for the common benefit. Two classes of research investigations are often recognized-fundamental and applied, but these classes merge into each other and it is often hard to distinguish one from the other. Fundamental research is carried out primarily to develop basic facts, but frequently these are found to have immediate economic value, while applied research, specifically aimed at economic values, often necessitates a preliminary fundamental investigation. Both are essential and both should proceed by scientific method. It is obvious in fuel technology that a knowledge of the physical and chemical constitution of the various coals is fundamental to their industrial utilization, and further, a knowledge of the way these coals react under different conditions of temperature, atmosphere, etc., is necessary in solving such problems as storage, combustion, carbonization, gasification, or con-version to liquid fuels. The wide range of coals, the complexity, of their constitution, and the many uses for coal, makes fuel research no simple subject but one with unending possibilities. The Research Council of Alberta, formerly known as the Scientific and Industrial Research Council of Alberta, was established in 1919, to promote the development and conservation of the natural resources of the Province. The work of the Council was arranged in six major divisions: Fuels; Geology; Road Materials; Soils; Natural Gas; and Forest Products. The office and laboratories are located in the University of Alberta. The Council was financed until the depression of 1933 by a separate vote of the Legislature, but since then has been continued, though on a much smaller scale, as one of the activities of the University. It might, however, be noted that although the Council is now in abeyance, a skeleton organization has been maintained so that it can be brought back to active service as soon as conditions warrant. Annual reports are still submitted to the Legislature. Funds have not been made available, however, for the publication of the last five reports.

Jan 1, 1942

By G. B. Harris, C. W. White

A study to investigate the recovery of base metals, notably copper, nickel, cobalt, zinc and manganese from iron-free concentrated chloride solutions using ion exchange was undertaken. In such solutions, apart from nickel and, to a lesser extent manganese, these metals are present predominantly as complex anions, and therefore conventional separation techniques based on cationic resins are not applicable. The results demonstrated that zinc, copper and cobalt can all be separately recovered leaving nickel and manganese behind. Specifically, zinc is a major nuisance element in nickel and cobalt processing, and the testwork showed that it can be preferentially removed prior to copper and cobalt. Selective resins for both copper and cobalt were identified, and it was demonstrated that the strength of the chloride background matrix has a significant effect on the efficiency of separation. An additional major advantage in such systems is that stripping can mostly be effected with water. Finally, some observations are made on the hurdles that must be overcome when attempting to introduce and commercialise new technologies.

Jan 1, 2015

By Feng Xue, Mi Xujun, Peng Lijun, Yin Xiangqian, Liu Dongmei, Xie Haofeng, Huang Guojie, Yang Zhen

The Age-hardening Cu-Cr alloys are extensively used in integrated circuit lead frame, railway contact wire, resistance welding electrode and continuous casting mold copper plate, owing to having an excellent combination of high electrical or thermal conductivity and high strength. High temperature performance is very important during the service process. Effect of Magnesium and Zirconium on softening behavior of Cr-Cr alloy are investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). During the softening process in the Cu-Cr alloy, the recrystallization process, grain growth and Cr precipitates coarsening are observed. The addition of Mg or Zr to the Cu-Cr alloy, the resistance to elevated temperature can be significantly improved, owing to being restrained the growth of the precipitates by segregating along precipitates surface. INTRODUCTION Age-hardening Cu-Cr system alloys can be widely uesed in many fileds such as electrodes for spot welding (Hatakeyama et al., 2008; Cheng, Shen & Yu, 2013; Zhou et al., 2016; Chbihi, Sauvage & Blavette, 2012), intergrated circuit lead frame (Hatakeyama et al., 2008; Cheng, Shen & Yu, 2013; Zhou et al., 2016; Liu et al., 2006; Pang et al., Xia et al., 2012; Wang et al., 2009; Huang et al., 2003; Cheng, Yu & Shen, 2014; Zhang et al., 2016; Li et al., 2007) and railway contact wire (Cheng, Shen & Yu, 2013; Zhou et al., 2016; Chbihi, Sauvage & Blavette, 2012; Liu et al., 2006; Pang et al., Xia et al., 2012; Wang et al., 2009; Huang et al., 2003), because it has high strength, good electrical and thermal conductivity. The precipitation behavior of binary or ternary Cu-Cr alloys had been investigated by many researchers (Chbihi, Sauvage & Blavette, 2012; Peng et al., 2017; Batra et al., 2002). In addition, to obtain additional mechanical properties without much deterioration in electrical conductivity, trace addition of alloying elements like Zr, Ag, rare metals (Y and Ce) and Mg are added into Cu-Cr alloy. The addition Mg to Cu-Cr alloy accelerated the process of precipitates nucleation and restrained the growth of the precipitates by segregating along precipitates surface during aging, which enhanced the stability of the deformation microstructure and improved the mechanical properties of the alloy (Zhao et al., 2018). Additional zirconium in Cu-Cr alloy enhances the strength by the decrease in inter-precipitate spacing of Cr precipitates and the formation of Cu5Zr phase (Chihiro, Ryoichi & Kazue, 2008). Owing to the decrease in inter-precipitation spacing of Cr precipitates and to the Ag-atom-drag effect on dislocation motion, the addition of Ag can increase in strength, stress relaxation resistance and without much deterioration in electrical conductivity (Chihiro, Ryoichi & Kazue, 2008). The enhance in strength and electrical conductivity of the Cu-Cr-Zr alloy by adding Ce and Y elements are attributed to removing oxygen and sulfur from as-cast alloy (Li et al., 2006). However, the effect of Mg or Zr element on microstructure and properties of Cu-Cr alloy during the softening process are not clear. Therefore, Microstructure evolution and properties of a Cu-Cr systems alloy were investigated in detail by OM and TEM. The Relationship between microstructure and properties of Cu-Cr systems alloy was also discussed.

Jan 1, 2019

By Beatrice Pierre, Juan Carrasco

Altonorte began as a concentrate roasting operation in 1988 under the name of Refimet. In 1993, a copper smelter was built with a design capacity of 203,000 tonnes per annum of concentrate. Since 2001, many technological advances have been made in Altonorte, where the biggest Noranda Reactor in the world is installed being the first Noranda Reactor reaching above one million tonnes of copper concentrates processed per annum. In 2013, Altonorte was acquired by Glencore. Recently due to various new environmental regulations in Chile, Altonorte has evolved to new standards of operation in order to reach the vision of becoming a World Class Smelter. This paper describes the path followed to improve safety, environmental performance, process capacity, reliability, and productivity. The foundation for the growth and success in Altonorte is our People. Employee engagement and branding of our cultural journey is what allows Altonorte to face the future with the certainty of becoming a World Class Smelter. INTRODUCTION Altonorte is located in Antofagasta, the mining capital in the north of Chile and is the last smelter built in Chile practically completed with second hand equipment. The biggest technological change in Altonorte occurred during the phase 3 expansion in 2003, where the old Reverberatory furnace was shut down and replaced by the biggest Noranda Reactor installed in the world. The vessel measures 5.3 m × 26m. ºAdditionally, this project contemplated a new rotary dryer, three (3) new Peirce Smith converters, new anode furnaces and a new Acid plant. The nominal capacity was to treat 816.000 tons of new concentrate per year. In 2008, a new expansion phase was implemented where a new double absorption acid plant replaced the oldest acid plant. Bottlenecks such as blowing capacity and oxygen availability were solved installing a new air blower and a new contract was negotiated with our oxygen supplier to increase oxygen availability up to 683 tpd. This improvement defined the current nominal capacity of 1.100.000 ton of new concentrate per year. Current process description All concentrates are received by trucks directly from domestic mines or from the Antofagasta international port in cases of imported concentrates; the concentrate warehouse has a capacity of 25 kt where the blend is prepared to feed the smelter.

Jan 1, 2019

By A. A. Millar

THE output of coal from the Province of Alberta reached its peak; in the year 1928, when 7,334,179 tons were produced. Following this, a steady decline was recorded, and in 1930 a low mark of 4,564, 290 tons was made. Since that time, however, the tendency has been upward, and this year (1937) 5,551,682 tons were produced, compared with 5,696, 375 tons in 1936 and 5,462,973 tons in 1935. The value of the output in 1937 was $14,434,969, against $14, 720,004 in 1936. The coals of Alberta have been classed under three heads, viz., domestic, sub-bituminous, and bituminous The domestic (or lignite) and the sub-bituminous coals are used chiefly for domestic purposes, with the possible exception of the smaller sizes and the output of the two stripping pits at Stereo and Coal Valley The bituminous output is used mainly by the railways, for locomotive purposes, which, in 1937, accounted for 80.6 per? cenr of the total sales of bituminous coal. A fair proportion is sold for stationary engine and steam purposes and, in 1937, 25,000 tons were used in making briquettes at plants operated by the Canmore Coal Company, Limited, and Brazeau Collieries, Limited. The International Coal & Coke Company, Limited, used 99,500 tons in their plant at Coleman, for making coke. The bulk of the 66,000 tons of coke produced was sold for use at the smelter at Trail, B.C.

Jan 1, 1938