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By J. E. Hawley

"IntroductionA STUDY of the trace elements in the ash •of coals from nine seams in the Sydney coalfield, Nova Scotia, was undertaken at the suggestion of Dr. W. A. Bell, Geological Survey of Canada, as a part of a larger study of these and other Nova Scotia coals being made by the Geological Survey and the Nova Scotia Department of Mines under the direction of Dr. P. A. Hacquebard.The main purpose of this investigation has been to •determine if a knowledge of the trace element distribution might be of assistance in the recognition of individual seams, the distinction of which is not always easy or positive in folded and faulted strata by ordinary stratigraphic and structural means.The study has been so conducted as to afford information on the variation of trace elements in individual petrographic intervals or divisions in each of the seams examined, intervals determined by Dr. Hacquebard on the basis of their banded ingredients, vitrain, clarain, durain, fusain, etc, as observed under the microscope in polished sections. The results, as well, indicate the trace element composition of the coals of the area as a whole, and quantitative data for fifteen elements are given, along with concentrations of thirteen other elements, stated in terms of intensity ratios. Data on distribution of germanium, though considered here along with other elements, are dealt with elsewhere*."

Jan 1, 1955

By H. M. Fisher, R. E. Snow, S. C. Sun

SEVERAL constructive and fundamental studies have been made in the analysis of data obtained from experiments carried on with batch ball and rod mills. The operating characteristics of ball milling in small continuous circuits have also been appraised. It is from these analyses that some of the theories of comminution have been developed. Relatively few studies of continuous rod milling have added significantly to the fundamental concepts, because seldom have they yielded sufficiently consistent results. Perhaps they have been too limited in their scope. Careful control of the variables in batch grinding is simple compared with that encountered in a continuous operation. This factor alone has discouraged many investigators. Occasionally results of systematic changes made in industrial rod mill circuits have been published, but usually the data are sketchy and are restricted because of the unwieldiness of the equipment used. The work, in general, has not been comprehensive; nevertheless it has provided empirical relationships that have bridged the gap between postulate and practice so that by proper manipulation of formulae, a mill designer can anticipate mill size and power requirements.14 Although operating variables of a small continuous mill are not so easy to control as with the batch mill, with present day devices, and with careful experimental work, consistent results can be obtained. Nearly four years ago, in the Process Laboratory, Allis-Chalmers Mfg. Co. began a systematic study of the effects of several variables upon the performance of the pilot rod mill. A mill was built in the laboratory to provide the versatility required for the proposed study. It was constructed in sections so that it could be operated, with a few modifications, as a rod mill 30 in. x 8 ft or 30 in. x 4 ft. The discharge end of the shell was flanged so that either an end peripheral discharge or an overflow discharge could be installed. Thus the performance of at least four types of mills could be studied merely by changing the type of discharge or the length of the mill shell. The grinding experiments were designed so that a study could be made of the way in which the mill speed, feed rate, and pulp density influenced the performance of both overflow and end peripheral discharge rod mills. Four sets of experimental data were collected from the four mill arrangements. The mill in each set of experiments was fed at four rates of feed depending on the length of the mill, at four pulp densities, and at five percentages of critical speed. Electrical and mechanical controls were in- stalled to regulate all these independent variables, and auxiliary devices were used to verify the precision of the controls at each point. The dependent variables used to quantify the experiments were the reduction ratio and the hew surface area produced as calculated from sieve analyses. These were incorporated with the energy factor by the calculation of both the new surface produced per unit of energy and the Bond work index.' Rod wear, as a dependent variable, was not studied because of the short period of operation for each run. Exclusive of repeat runs, each set of experiments yielded 80 products, and the total study at least 320 products, all of which were quantified. With the operating information collected, these data presented a bewildering accumulation. Statistical analysis has been invaluable in unraveling the confusion and in presenting a means of establishing the nature and the magnitude of the significant variables. Data presented in this paper are those from the 30 in. x 4 ft end peripheral discharge rod mill, Fig. 1, when limestone was ground at feed rates of 1000, 2000, 4000, and 5000 lb per hr, at pulp densities of 50, 60, 70, and 80 pct solids, and at mill speeds of 50, 60, 70, 80, and 90 pct of the critical speed. These 80 tests have all been run at least twice, and occasionally a third time, to prove that the data obtained were reproducible. The techniques of operation and the methods of quantification of results are described in the following pages and the results analyzed statistically to show the significant variables. The variables are plotted to show the relationships that exist. A massive dolomitic limestone from Waukesha Lime and Stone Co. was used for feed during these experiments because of its availability and its tex-tural uniformity. This limestone analyzed 28.7 pct CaO, 21.0 pct MgO, 6.0 pct SiO2, 0.4 pct A1²O³, and 0.3 pct Fe²O³ and had a loss on ignition of 44.1 pct. It had a rod mill grindability at 14 mesh of 9.6 grams per revolution from which a work index of 13.9 was calculated. The ball mill grindability at

Jan 1, 1955

By Reno H. Sales

Our colleagues cannot in the future earn reputations and medals for achievements in milling and smelting ore and for successful management of mining companies, if some one doesn't keep finding and mining the ore to mill and smelt and to provide the basis for the good management. Good ore seems sometimes to be quite helpful to good management, and good ore is not as easy to find as it used to be. And there are still more reasons, why—when this honor had been decided upon and named for Mr. Daniel C. Jackling—it should be initially conferred on Reno H. Sales. . The terms of reference of the award are that it should be conferred upon an individual working in the fields of mining, geology, geophysics, who has made an outstanding contribution to the progress of technology in one or more of those fields. And in this initial year (the earlier years are the easiest) just that was done. I think I could get away with it amongst the old-timers of my generation if I say that this time they made the award to the individual, who made the outstanding contribution. But, as Al Smith used to say, "Let's look at the record." Really, the record is mixed up a little with extra-lateral litigation—the old-time "apex cases" under Section 2322 of the Revised Statutes. Reno Sales doesn't like such litigation, but there is little question that the urgency, generated by conflicting claims of intra-limital and extra-lateral rights, and consequent necessity for committing to records and maps the complications of Butte structure, did advance—and by several years—the first continuous, accurate, systematic, and scientific portrayal of the geological and mineralogical details of what is, after all, the most important and the most complicated copper district—at least in North America. Prior to Sales' time, some of the most eminent of geologists often waived details. One geologist took the judge to the window to show him the Rarus fault going through a notch in the Continental Divide. The entertaining testimony in the Bluebird litigation was as perfect in literary style as it was innocent of the criteria by which faulting and lack of continuity of vein structure are now recognized. At any rate, this need for an accurate record of structure was in the background—to whatever extent it was, or was not, the etiological agent—for formation of the Geological Department of the Amalgamated Copper Co. in and about the year 1900. Charles W. Goodale was at that time the head of the Boston & Montana, and John D. Ryan succeeded William Scallon as the president of Anaconda Copper Mining Co. in 1905. Horace V. Winchell, for years a specialist in extra-lateral litigation, was perhaps the man who at that date had the vision, the persuasive weight with the management, and the willingness to defend the idea of large current expenditures (as then viewed) for a complete and sys-

Jan 1, 1955

By L. H. Banning

Recent dry-top electric smelting tests at the Northwest Electrodevelopment Experiment Station, Albany, Oreg., indicate that a high-titanium slag and a good grade of pig iron can be produced from alluvial Idaho ilmenite. A total of 120 tons of concentrates were smelted during this investigation, to yield an average of 0.5 ton of slag and 0.3 ton of pig iron per ton of ilmenite. Power consumption averaged 1,400 kv.-hr. per ton of ilmenite, at a feed rate of 400 to 500 pounds per hour, when operating at an electrical energy input of 290 to 370 kilowatts. The optimum operating voltage appeared to be 110 volts, phase-to-phase. Graphite electrode consumption averaged 15.6 pounds per ton of ilmenite smelted. Magnesite furnace refractory withstood the corrosive action of the hot metal and slag better than carbon refractory.

Jan 1, 1955

By W. A. Stickney

This report summarizes the results of laboratory tests of five samples of low-grade phosphate ores from Idaho. The laboratory test work has demonstrated that by grinding, desliming, and flotation a portion of the siliceous gangue can be removed. The highly carbonaceous ores responded successfully to treatment after preroasting, to produce a plus-30-percent-P205 product. It has been found that highly siliceous ores, as represented by the samples treated, are more readily amenable to concentration than ores high in calcium carbonate. Of the five samples tested, four were amenable to concentration to a product containing over 30 percent P205. One sample, from the Conda, second bed, was not amenable to mineral-dressing treatment to produce a plus-25-percent-P205 product.

Jan 1, 1955

The Black Hills Mineral Atlas briefly summarizes all important data available on the mines and mineral deposits in the Black Hills that have been explored, developed, mined, or located. The purpose of the atlas is threefold; First, from available data the general potentialities of the Black Hills region can be determined, although it is not possible to calculate actual ore reserves; second, it will provide the necessary basic information regarding a given property or commodity for further detailed study; and third, the compilation is a comprehensive directory of Black Hills deposits.

Jan 1, 1955

By H. P. Holmes

Tonnage quantities of hafnium metal have been prepared in Kroll-process equipment designed for producing zirconium. Some slight process modifications have been necessary, but overall operation is the same as for zirconium. Hafnium oxide is chlorinated in the presence of carbon and the resultant hafnium tetrachloride reduced by magnesium metal. Byproduct magnesium chloride is removed in a high-vacuum distillation step and the hafnium sponge metal crushed for further use. Arc-melted metal can be forged and rolled to sheet, but the best material produced to date would not be considered cold ductile. INTRODUCTION This investigation is part of the program for the production of pure metals from domestic and foreign ores that has been underway at the Bureau of Mines for several years. It was done in cooperation with the Atomic Energy Commission and the Bureau of Ships.

Jan 1, 1955

By Frank Doxley

"FIRST OF ALL I should like to express to the members my sincere thanks for having had the privilege of serving them as President during the year now ending, to the Council for their guidance, and to the Secretary-Treasurer for his untiring efforts on both the Society's and my behalf during my year of office.During the .past five years the Canadian •Coal picture has changed considerably. In the West, production has been almost halved and many mines have been closed, due to the development and expansion of oil and natural gas industries, which, with some imported residual oil -on the Pacific coast -have provided competition which has been impossible to meet. The two major railway companies have embarked on an oil-burning and dieselization .programme and with this has .been lost one of the largest available markets for coal. Natural gas pipe-line installations still further threaten the remaining outlets for Western coal.In the East, retention of markets has also been a •problem, due to the intense competition provided by imported American •coal and the importation of residual oil.Because of cost it is impossible for central industrial Canada to be supplied with .coal from the Maritimes and markets are, therefore, restricted to fringe areas in Ontario and Quebec, and the Maritime Provinces.The dieselization programme of the Canadian National Rail ways has meant the loss of a large market for Nova Scotian coal and it is fair to assume that within a comparatively short time the market will be completely lost."

Jan 1, 1955

By Wm. Snow, J. R. Wallace, E. P. Duchemin

"GeneralA NOT INCONSIDERABLE proportion of the Canadian economy is dependent on the coal mining industry. This is particularly true of the eastern portion of Canada and especially so of the ( authors') province of Nova Scotia. Much has been said about the trying economic straits of the coal industry in Nova Scotia ( 1), faced, as it is, with difficult mining problems, with considerable distance from large markets, and with •competition from other (and usually foreign) fuels. It is of particular interest, at this time, therefore, to discuss one of the larger outlets for coal -that of the production of metallurgical coke.Scope of PaperWhile the title of this paper indicates that it deals with Metallurgical Coke in Canada, the authors beg leave to treat the Canadian industry very briefly and to deal specifically with coal, •coke, and smelting problems with which they are familiar, namely, the operation of the Dominion Steel and Coal Corporation in the Sydney, N.S., area. No mention is made of metallurgical coke for use in the •many foundries in Canada or in the non-ferrons metallurgical industries.Coal and Coke StatisticsA few statistics of the total output of .Canadian coal, production of metallurgical coke, and similar figures for the Dosco holdings (Sydney area only) are shown in Table I."

Jan 1, 1955

By E. J. Gleim

[THE ORGANIC act under which Federal Bureau of Mines was established provided for the investigation of the safe use of electricity in mines. Each Congress appropriates funds for conducting this investigation. As part of this investigation, electrical apparatus used in mines is studied to determine if its operation and use might introduce a hazard. From this study, certain safety standards have been developed. These standards, established with the aid of both the manufacturer and user of such apparatus, are published in schedules, and apparatus that complies with the requirements set forth these schedules is classified as "permissible." This term is defined to designate apparatus as "completely assembled and conforming in every respect with the design formally approved by the Bureau of Mines." In the judgment of the Bureau, the manufacturers of such apparatus have adhered to certain minimum standards of safety in supplying a product that when properly used and maintained is safe for operation in mines where flammable gas or coal dust may accumulate. This work of the Bureau of Mines for increasing safety does not make it obligatory for manufacturers of mine equipment to produce only that of permissible classification. Before the effective date of the Federal Mine Safety Code,5 the Bureau sought to promote safety by recommending that mine operators install permissible equipment in gassy mines as a preventive measure against gas and dust explosions initiated by electrical equipment. For some years, the mining laws of several States have prescribed the conditions under which permissible equipment must be used. The Federal Mine Safety Code requires that ?all new electric face equipment and replacements of equipment purchased for mines where nonpermissible equipment is now being used shall be of a permissible type approved by the United States Bureau of Mines,]

Jan 1, 1955

By Y. O. Fortier

"ForewordTHE Arctic Archipelago and northern Greenland contain an orogenic region that is as much as 300 miles wide and over 1,400 miles long. It occupies much of what was formerly classified with the Arctic Plains and grouped with other plains and lowlands of Canada as one main geological division. It is proposed that this folded region be designated the Innuitian Region and be recognized as one of the main geological divisions of Canada.Canada's main geological divisions (see Geological Survey of Canada, 1947) have been considered as consisting of a central shield, largely surrounded by plains that separate it from eastern and western mountains. The plains include the Interior Plains, the St. Lawrence Lowlands, the Arctic Plains or Low-lands, and the Hudson Bay Lowland, which is in the central part of the Shield. Plains and mountains are, strictly speaking, physiographic terms, but because mountains are generally folded regions and plains are generally made of undisturbed strata, such terms are useful vehicles to express the fundamental make-up of the land. Nevertheless, it is preferable to use the terms Appalachian and Cordilleran 'Regions' rather than 'Mountains', as those geological divisions are not exclusively made of mountains.Because of the lack of more definite information, the 'Arctic Plains' have included, in the past, regions with plateaux two to four thousand feet above the nearby sea, mountain ranges reaching approximately 10,000 feet above sea level, and regions of folded strata."

Jan 1, 1955

By M. P. Tixier, A. Poupon, M. E. Loy

Simple qualitative methods are explained for identifying those shaly sands in a well that are most likely to contain oil. A need for more precise measurement of the variables that enter shaly sand analysis is indicated. Field examples are given to illustrate the methods. A theoretical discussion of the quantitative interpretation of shaly sands is given as a basis for discussion and as a guide for the future. While not generally capable of practical application at the present time because of the lack of sufficient accuracy of the electric log data, these methods may become more feasible in the future as the result of the improved logging methods now being introduced. INTRODUCTION Experience has shown that for porous formations containing only a negligible amount of clayey material, reliable information on the fluid saturation and porosity of the reservoir rocks can usually be derived from the electrical logs. The interpretation is based on empirical formulae relating the true resistivity of a porous formation to its lithologic character, to the resistivity of the interstitial water, and to the proportions of water and hydrocarbons in the pores.' If the resistivity of the interstitial water is not known, its approximate value can be derived from the SP curve.2,3 The porosity can usually be determined to a good approximation from a MicroLog, or a MicroLaterolog.4,5 When the reservoir rocks contain an appreciable percentage of clayey material, an additional factor is introduced into the analysis. In a clean formation, the matrix is an electrical insulator, so that the ability of the formation to conduct current is due only to the conductivity of the electrolytes in the pores; in a shaly formation, the shale constitutes a part of the rock matrix able to conduct current, and influences the resistivity of the formation. On the other hand, the spontaneous emf's and the circulation of the SP currents are also responsive to the presence of the shaly material. All other factors being the same, the deflection of the SP curve opposite a shaly permeable formation is smaller than the deflection which would be observed if the formation were clean. The effects of the presence of shale on the resistivity and on the SP curves in a shaly formation are functions of the amount, of the specific resistivity, and of the geometrical distribution of the shaly material within the formation. The presence of shale therefore constitutes an important complication in electrical log interpretation. It is easy to realize, for example, that the presence of a large amount of clayey material in a sand may have such a predominant effect that the resistivity of the sand will not change very much, whether the pores are entirely filled with connate water, or contain a high saturation of hydrocarbons. Important research projects have been undertaken to investigate the influence of shales and to find a way to allow for this influence in the interpretation of a log. The problem of the SP in shaly sands was analyzed mathematically by H. G. Doll"' for the case of sands with shale laminations. Formulae expressing the resistivity of shaly formations were proposed by Patnode and Wyllie8 and de Witte.9 Other quite interesting theoretical and experimental results have been published by various authors.l0,ll,12,l3,14 The purpose of the present paper is to discuss an approach to electrical log interpretation in shaly sands. This approach is based partly on some of the theoretical and experimental data available in the literature and partly on observations made on actual field logs. Comparatively simple methods for qualitative and semi-quantitative analysis are described. These methods depend principally upon information provided by the electrical logs.

Jan 1, 1955

By Louis Frost

"1N 1951, the Dominion Steel and Coal Corporation, as part of a programme of modernization in their coal mining operations at Sydney Mines and Glace Bay, Nova Scotia, undertook the development of two large cross-measure tunnels, which were to be used for the purpose of raising the coal from the underground workings by conveyor belts direct to wash plants located on the surface.These tunnels were to reach from the surface to central loading points underground located at a depth of 600 and 900 feet, respectively. They were to be driven on a pitching gradient of 11 degrees to the horizontal, and they were to reach a length of 3,600 feet in the Sydney Mines area and 10,000 feet in the Glace Bay area.The longer tunnel, 19 feet in diameter, was driven a distance of 1,500 feet and, for domestic reasons, bas not yet been •completed. The other tunnel, in the Sydney Mines area, 18 feet in diameter, is steel supported and concreted throughout its entire length. This tunnel has been completed and will be in operation at an early date.The development of this particutar tunnel posed an additional problem, as the rock through which it had to pass was considered to be water-bearing. In the sinking of Princess Colliery shafts in 1866, a great deal of water had been encountered, and it had been necessary, while sinking, to line the shaft with cast-iron tubbing through the water-bearing strata. The shaft had to be lined for a depth of 300 feet at the upper end. It was anticipated that we would meet with difficulty in driving the tunnel through this strata."

Jan 1, 1955

By H. W. Hitzrot

SEPARATING a mixture of particle sizes of material suspended in a liquid medium is by no means an exact science. Selecting machines for individual classifying operations is even more difficult. The plant operator's own background is of course invaluable, and considerable help may be obtained from technical articles, talks with sales engineers, and handbooks on ore dressing. These several sources of information, however, are difficult to marshal in proper perspective for the major decision on classification units that an operator may be called upon to make. To the present writer's knowledge this assembly of facts is not available in handbooks, and technical papers are scarce on classification equipment developed in the past five or six years. It is believed that this paper will be helpful to users of classification equipment at this particular period in the development of hydro-classification. For easy reference the following classification units now available and in use in metallurgical and industrial operations are listed below, with a brief description of each. Unit-type classifiers, bowl classifiers, and bowl desiltors are all rectangular tanks, slightly tilted, with reciprocating rakes or screws to remove settled sands. The unit-type classifier, Figs. 1 and 2, is available in widths from 14 in. to 20 ft and lengths up to 40 ft. The shallow bowl of the bowl classifier, Fig. 3, equipped with rotating rakes, is superimposed on the lower end of the tank. Reciprocating rake compartments for this design range from 18 in. to 20 ft wide. Bowl diameters vary from 4 to 28 ft. The flat-bottomed bowl of the desiltor, Fig. 4, of relatively large diameter, is equipped with rakes rotating outward and partly over a pit, which is created by extension of the rectangular tank into and under the bowl section. Bowl desiltors are available with reciprocating rake sections 4 to 20 ft wide and bowls from 20 to 50 ft in diam. The bowl desiltor is used for applications beyond the range of the bowl classifier. The hydroseparator, Figs. 5 and 6, is a circular tank equipped with slowly rotating rake arms, set on a slope, with interrupted rake or spiral blades to move the settled solids to a central discharge cone. Tank diameters vary from 4 to 250 ft. Tank depths at center are 2 to 3 ft for small units and up to 25 ft for larger units. Hydraulic classifiers of the sizer and super-sorter types, Figs. 7 and 8, are narrow, deep, rectangular tanks divided by vertical baffles into a series of pockets. Hydraulic water is added near the bottom of each pocket. Perforated constriction plates, spiral flow arrangements, or jets are used to disseminate the water under pressure (hydraulic water) throughout the bed of material in the pocket. Discharge valves on each pocket are operated automatically by a pneumatic mechanism, a pincer-type mechanism, or a pressure control and motor combination actuated by a hydrostatic tube within the pocket. Hydraulic classifiers are available in 4, 5, 6, and 8-pocket units of varying constriction plate areas to suit conditions. There is now a jet sizer of unit pocket design that can be made up in 1 to 25 sections or more to accommodate sizing requirements. The hydroscillator, Fig. 9, is a rectangular tank set on a slope of 3 to 4 in. per ft. A bowl is superimposed on the lower end. The bowl bottom is an oscillating rubber-covered disk, perforated to allow hydraulic water introduced beneath the disk to set up a teeter bed and thus produce an oversize or rake product exceptionally free of slimes, and material minus the mesh of separation. A shallow dam at the periphery of the bowl allows the coarse or oversize fraction to spill over and drop down into the tank compartment, where it is moved up the deck by reciprocating rakes. The material, minus the mesh of separation, overflows a circular and stationary weir which is several inches higher than the dam on the oscillating disk. It is carried off in a circular launder in the usual manner. These units are available in bowl diameters from 4 to 14 ft and with reciprocating rake compartment widths to suit the tons per hour to be handled. Centrifugal classifiers include the solid bowl centrifuge and the cyclone classifier. The solid bowl centrifuge, Fig. 10, consists of a truncated cone fixed to a horizontal shaft and rotating at high speed. An internal spiral rotating at slightly less speed continuously removes solids deposited on the inner surface of the cone, or bowl. Feed enters the cone by means of the hollow center shaft. Overflow leaves through ports at the large end of the cone, and oversize solids, moved by the spiral, exit through ports at the small end. Centrifugal classifiers of this type are available in cone diameters from 18 to 54 in. The cyclone classifier, Fig. 11, is a stationary cone having a cylindrical upper section and a lower cone section. Feed is introduced tangentially into the upper cylindrical section under pressure from a hydrostatic head or by means of a pump. Centrifugal force thus induced effects a classification within the cone, the fine sizes being carried off in the overflow through an opening at the top of the cylindrical section. Coarse solids at relatively high pulp density exit through a control valve at the apex of the lower cone section. Cyclone classifiers are available in 3, 6, 12, 14, 24, and 30-in. diam. The cone classifier, Fig. 12, is a steel-plate cone with sides usually about 60" from horizontal. It contains no rotating mechanism. Feed enters a feed-well at center and classification is effected by gravity and pulp density. Fines are carried off in the flow over a peripheral weir at the top of the cone. Settled solids exit through an opening at the apex. An apex valve actuated through levers and rods by the pulp density in the lower cone section is usually supplied. Diameters are usually maximum at 8 ft.

Jan 1, 1955

By W. L. Dare

This circular is the first of a series of publications describing uranium mining on the Colorado Plateau. Later circulars are planned in which exploration, development, and mining methods and costs will be described after a detailed study of various operations. Because of the introductory character of this paper, those well-publicized phases of the industry such as geography, history, prospecting, and exploration are described but briefly. Primarily, attention has been devoted to the general problems that are encountered in mining ore bodies and to the factors that affect the selection of development and mining methods. Those familiar with mining may class the information contained in this paper as elementary; however, its inclusion is considered necessary for the completeness of the series of papers. It will also serve as a source of information for people who are interested in uranium but are unfamiliar with mining.

Jan 1, 1955

By Sherwin F. Kelly

"THE TITLE I have chosen is certainly not one of those self-explanatory ones. I shall endeavour to make its significance clear during my remarks but, in the hope of minimizing that inevitable exodus which follows a good lunch such as this, I am going to withhold the final key to its meaning until the very last sentence of this talk.Some explanation is due at the beginning, however, so for those of you unfamiliar with Spanish I will explain that casa means house, or home. The casa about which I am going to talk necessitates a wide .and generous interpretation of the word, because I am using it to indicate principally that portion of the North American continent which is the home, in the western hemisphere, of British and American ideals of justice and freedom, the dignity of the individual and his right to exercise private initiative .and engage in private enterprise. In a wider sense, I am including the entire western hemisphere, which may yet stand as the last bulwark of political and industrial democracy.As for the treasures of which I am about to speak, may I remind you that there are no• material treasures but those derived from the earth, and they are derived by one of two processes, -mining and farming. These two fundamental industries are the basis, and the sole material basis, of our welfare, our wealth, our very existence. From farming, whether it be farming of the land. or farming of the sea, we obtain the food to keep us alive, healthy and able to work."

Jan 1, 1955

By M. R. Geer

This report presents the results of washability examinations of seven coals from the principal coal-producing fields of Montana. A complete performance test of the Baum-type jig operated at one of the mines is included, as are the results of cleaning tests made on two of the coals in a dense-medium pilot plant. The coals examined from the Red Lodge, Bull Mountain, and Forsyth fields are comparatively easy to clean. Ash contents of 5 to 10 percent can be obtained at yields of washed coal ranging from 90 to 95 percent. The coal from the Great Falls field, however, could not be cleaned readily to less than 14 percent ash, and the rejection of impurity would amount to over 25 percent. The two coals treated in the dense-medium pilot plant were characterized by sharp separation of impurity, high recovery efficiency, and satisfactory reduction in ash content.

Jan 1, 1955

By W. L. Ott, J. E. Hawley, C. L. Lewis

"IntroductionTHE APPLICATION of spectrochemical analysis to metals of the platinum group was advocated by Harvey (3) as follows: ""The spectra of the platinum group metals have been studied less than many of the more common metals. The rarity of occurrence of these elements makes the analysis relatively unusual. Potentially, the analysis of this group is an excellent application of spectrographic methods, particularly in contrast to the tedious chemical procedure"".Wichers (8) divides platinum-metal analysis into three broad divisions as follows :( 1) The detection and estimation of these metals in other materials, e.g., ores, where the amounts present are very small.(2) The detection and estimation of impurities in the refined metals themselves ....(3) The analysis of alloys of the platinum metals .....The present paper deals with the second division: analysis of refined rhodium.Research on spectrochemical techniques for determination of trace contaminants in refined platinum metals was begun at Queen's University in 1949, under the supervision of Professor J. E. Hawley. Since 1953, the work has been continued in the Metallurgical Laboratories of Falconbridge Nickel Mines, Limited. Techniques for spectrochemical analysis of refined platinum and palladium have been published ( 4, 5). A technique for analysis of refined iridium has been developed but not yet published."

Jan 1, 1955

By W. D. Mcmillan

Important reserves of nickel ore occur in the Levies district in Oriente, Cuba. The area is mountainous and mostly covered by heavy vegetation. The ore bodies comprise surface tracts of nickeliferous laterite underlain with decomposed serpentine of ore grade. The Cuban Nickel Co., a wholly owned United States Government corporation, owns a plant for leaching the nickel from its ores at Nicaro, Oriente, Cuba, Between December 1943 and March 31, 1954, 5,902,225 short tons of ore was treated, with a recovery of 116,206,519 pounds of nickel (52,711 metric tons). In 1953, 1,330, 224 short tons of ore was mined and 27;"3,129 pounds of nickel produced. The Cuban Nickel Co. also owns a townsite, with the necessary facilities, mining equipment, and 11 miles of railroad. Ore for the plant has been produced from the Ocujal-San Juan claims on lends owned by the Nicaro Nickel Co., a sub¬sidiary of Freeport Sulphur Co. The Government enterprise is man-aged by the Nickel Processing Corp. The Cuban Nickel Co. has denounced mineral concessions and has purchased other claims from private owners.

Jan 1, 1955

By M. R. Geer

Full-seam mining with continuous mining machines in dirty coal beds may increase loss of coal in the washery refuse. At one mine mentioned in this report the loss of salable coal was increased sixfold. Cleaning trials were made on three samples of jig refuse in a dense-medium pilot plant to demonstrate the application of this process to the recovery of coal from waste. These tests demonstrated that coal could be separated from impurity with the same degree of sharpness obtained in treating raw coal by dense medium. However, the recovery efficiency achieved in treating refuse averaged distinctly lower than that possible with raw coal because of the greater proportion of intermediate-density material in the feed and the lower yield of clean coal.

Jan 1, 1955