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By C. E. White

History The Con-Rycon mine is situated in the Yellowknife mining district, North West Territories, 608 air miles north of Edmonton, Alberta. The earliest reported discovery of gold in the area was made in 1898 but no extensive exploration occurred until 1928. The birth of Yellowknife as a mining community took place in 1934 with the staking of the Rich group and subsequent shipping of 16 tons of high grade ore. The Giant group was also among the claims staked in 1934, and later staking showed a tendency to close the gap between these two properties. In the fall of 1935, the A.Y.E. claims, situated south of the Giant group, were staked to cover a discovery of the Geological Survey of Canada and, after general release of the Survey's information, the adjoining ground was staked. These claims included the Con, Negus, Meg, and Kam groups. In 1936 four lapsed claims were re-staked as the P and G group and later acquired by Rycon Mines, Limited, controlled by the Consolidated Mining and Smelting Company of Canada, Limited. The Con and various adjacent groups owned by Cominco are now operated with the Rycon under one management. Surface trenching on the Con property started in 1936 and, during the fall and winter of 1936-37, a 60- foot 5 ft. by 9 ft. inclined prospect shaft was sunk. The encouragement provided by the shaft and diamond drilling in 1937 led to the decision to establish a mining plant, and in August, 1938, the 100-ton cyanide mill produced its first brick- the first gold brick poured in the history of the North West Territories. In November, 1938, the mill was enlarged to a 175-ton capacity and operated at this rate until 1941, when refractory ore was encountered. This situation was met by the installation of flotation and roasting units and, at the same time, the milling capacity was increased to 300 tons daily. Labour shortages and Government restrictions forced a reduction of output and in 1943 milling was suspended while mine development continued on a reduced scale throughout the war years. The present full-scale of operations was resumed in 1946 and the total production to the end of 1948 amounted to 288,853 oz. gold and 72,347 oz. silver.

Jan 1, 1949

By E. Lee Cameron

The old mine workings on four barite-fluorite veins of the Lake Ainslie district, Nova Scotia, were opened recently and channel sampled. The samples were then forwarded to the Ore Dressing Laboratories, Bureau of Mines, Ottawa, for chemical analyses. Following the analyses, the sample rejects were combined to form bulk samples, representing ore from each vein, for small-scale batch test work. Tonnage samples from the veins, for pilot mill testing, were submitted when requested by the Bureau. The results of the analyses on the channel samples showed that there are two grades of ore in the di strict, represented, for test purposes, by the Trout River vein and Johnson vein ores. Small-scale and pilot-plant test work was undertaken on both these ores. The Trout River ore is amenable co concentration but, because of the high-barite-co-fluorite-co-calcite ratio, a fluorite concentrate was not obtainable from the Johnson vein ore as received. However, Johnson ore blended in a 1 :1 ratio with Trout River ore gave a mill feed that was readily concentrated. The test work on these ores showed that the following concentrates are obtainable : (a) A barite concentrate, with a recovery of 85 to 95 per cent of the available barite, analysing 93 co 96 per cent BaS04, 4 co 6 per cent CaF,, and 0.5 co 2 per cent CaCO3. (b) A fluorite concentrate, with a recovery of 80 co 85 per cent of the available fluorite, analysing 94 to 97 per cent CaF, , 1 to 3 per cent BaSO., and 1 to 3 per cent CaCO3

Jan 1, 1945

By H. A. Pearse

The history of the flotation process, as applied to the practical field of ore dressing, dates back somewhat less than twenty years; yet this fact may be overlooked in view of the present universal dependence on this process in the concentration of almost all classes of ore. It is therefore interesting to recall that Britannia was the scene of some of the earliest experiments with flotation on a commercial scale. In 1911, sixteen years ago, an Elmore vacuum machine was operated for several months with encouraging results. In 1913, some time before flotation was very generally adopted elsewhere, a Minerals Separation plant, capable of treating 600 tons daily, was operating successfully at Britannia. Considering how little was known of the theory and practice of flotation at that time, the recovery was remarkably good, but it was not until the present mill was completed in 1923 that any attempt was made to raise the concentrate grade by differential flotation, or, in other words, to float the chalcopyrite while rejecting the then worthless pyrite with the tailings. The first ore passed through the present concentrator in March, 1923. As originally designed, the rated capacity was for 2,000-2,500 tons, but this has been increased year by year, until at the present time 4,000 tons daily can be treated economically. During the first few months of operation the concentrate grade averaged only 10-11 per cent Cu, but by the end of 1923 this had been raised to over 20 per cent, due to the elimination of the pyrite by differential flotation. In 1923 the tailings averaged approximately 0.25 per cent Cu, but also in the matter of recovery a considerable improvement has been effected, for during the year 1926 an average tailing of 0.15 per cent Cu was maintained.

Jan 1, 1927

By V. F. STANLEY

THERE is not the slightest doubt that the present recoveries of valuable minerals by the Broken Hill mills could be improved, and that further machinery would be installed for the purpose if it could be assured that a high price of metals would be maintained; but concentration, like all other com¬mercial propositions, is a question of profit and loss, and no sensible metallurgist would carry out his work in such a manner as to obtain high recoveries at a financial loss to his company. There is a point in all concentration at which the added money obtained from the higher recovery of minerals is balanced by the extra cost of obtaining the last part of the recovery; a wise metallurgist will be content with his work before his working-expenditure reaches this point. To a casual observer, the work being done by the various Broken Hill mills is identically the same. A closer investigation will show that this is far from being the case, for it is a remarkable fact that, although the larger mines extend over a length of approximately only 2 miles, such a difference in the physical and chemical properties of the ores exists that, from the first reduction downwards, special treatment is necessary in each case, and hardly any two mills are identical in operation. The details of this paper refer directly- to the work of one . particular mill in Broken Hill, for the reason that the ore from each mine presents special difficulties and requires its own special treatment. I have selected the mill referred to because it has been constructed and modified under my supervision.

Sep 1, 1909

By J. S. Godard

The mining developments in western Quebec have shown the ores of this district to be more complex in character than was at first expected. When the initial discoveries were made it was thought that the ores would be similar in character to those of Kirkland Lake and Porcupine areas. Developments have since shown that although the ores along the southern margin of the belt are somewhat similar, those within the belt, constituting by far the greater proportion, are vastly different, being complex mixtures of base-metal sulphides carrying values in the precious metals. These mixtures of base-metal sulphides of copper, zinc, and iron, present several problems to the metallurgist, especially in their concentration into marketable products. For the purpose .of this paper the following classification may be made of the ores of the district. Group I. - Milling Ores: (a) Ores in which~ arsenopyrite is the predominating sulphide. In this class of ore the gold occurs in fractures in the quartz and is associated to a lesser extent with the arsenopyrite and pyrite. Examples of this class of ore are the Granada, south of Pelletier lake, and the O'Brien and the Thompson in Cadillac township. (b) Ores in which iron pyrite is the predominating sulphide and gold is the valuable constituent. This may also be classed as a concentrating ore-Group III.

Jan 1, 1928

By M. N. Nabighian

Utilization of x-ray diffraction data for mineral identification has been well documented and accepted as an analytical tool in industrial and research organizations. However, the search for new methods to minimize errors affecting measured reflection intensities is being carried out by all concerned. Recent application of computer capability has greatly reduced the time required in handling data for mineral analysis and has increased the capability of accepting more data for greater precision. The purpose of this communication is (1) to describe the concept of cross-power in XRD analysis, and (2) to show that direct comparison analysis for multiphase systems has improved analytical accuracy when all available x-ray diffraction data are used in conjunction with high speed data processing by computer.

Jan 1, 1972

By A. J. Dudzik

In 2006 Arch Materials initiated the development of an underground limestone mining complex. The decision to proceed with the project was the end result of several years of market research and geological reconnaissance. The scope of the project included the construction of two declines to the mining horizons located approximately 900 feet below the surface, the means and methods of this phase will be the primary focus of this discussion. The design, fabrication and erection of a state of the art crushing and screening processing plant which when completed will have the primary crushing located on the mine level allowing uniformly sized material to be brought to the surface by means of a highly efficient conveyor system and a surface portion of the plant where material would be additionally processed, screened and stockpiled into specific product types. Also included in the scope of the project is the construction of offices, warehouse and shop facilities necessary to support the operations, commercial sales and distribution of the finished products.

Jan 1, 2010

By F. T. Havard

(Canal Zone meeting, November, 1910.) I. INTRODUCTION. THE present truce in litigation between Western smelting and ranching interests gives opportunity for a summary of the results achieved by metallurgists in condensing fume and de-acidifying furnace-gases. In the absence of complete records of past experiments, there has been a good deal of unnecessary duplication of attempts and' failures. Yet, especially under the recent policy of our large corporations, looking to the economic recovery of the values of by- and waste products, original and, in some cases, effective measures have been developed by American metallurgists. In the case of Bliss vs. the Anaconda Copper Mining Co., the Montana Supreme Court, recognizing the progressive efforts made to render the flue-gases innocuous, and the value to the community of the smelting company's operations, refused to hamper its work, and returned a verdict in favor of the defendant. In the trial, the experimental firms of the company in the so-called "affected region" were proved to be thriving perfectly, showing that immunity was guaranteed to vegetation and stock by the wide distribution of the sulphurous acid gas in the dry air of Montana. Indeed, L. S. Austin has proved that by the time the fume is 4,000 ft.. distant from the stack, the percentage of sulphurous acid has been diminished from 2.28 to 0.00045; and Angus Smith has shown that rain must contain 40 parts per million of free acid before vegetation is affected. The arsenic in the stack-gases is but a very small part of the original content of the ore, of which 80 per cent. and over is rejected in the concentrator and furnace waste-products or recovered in the flues. Nevertheless, neither the peace in Montana nor the armistice

Aug 1, 1910

The sulphide ores of the Kalgoorlie goldfield have long been looked upon as' refractory, involving special metallurgical treatment. For many years two kinds of treatment have been practised-(l) wet treatment, including fine grinding, amalgamation or concentration of the free gold, concentration of the sulphide minerals with subsequent roasting and cyanidation, and cyanidation or bromo-cyanidation of the residue from the concentrating operation; (2) dry-crushing of the ore and roasting the whole of thecrushed ore, amalgamation of the gold in the calcine during fine grading, followed by cyanidation. The wet treatment was advanced a stage further when, in 1929, the Lake View and Star Ltd. adopted large scale flotation. As a consequence, however, further metallurgical problems were introduced. This paper covers the investigation, ,of one of the most prominent of these problems.Flotation preceded by strakes was satisfactory to a point.The flotation concentrate consisted largely of auriferous pyrite and tellurides, and the gangue minerals in the concentrate were practically barren.Several sources of loss of gold values were, however, found to be associated with this circuit, viz.-(a) There was the loss of gold in the flotation tailing.(b) Loss by dusting during roasting of the flotation concentrate.(c) Loss of gold in the cyanided residue.

Jan 1, 1937

By David T. Day

IN 1897 I published a proposed explanation t for the variation in color and specific gravity of Pennsylvania oils. A resume of this subject was also presented at the First International Petroleum Congress, in Paris, in 1900. Since that time much experimental work bearing upon this explanation has been carried on by myself, in the United States Geological Survey, and under my direction, by Dr. J. Elliott Gilpin, Marshall P. Cram, and 0. E. Bransky, at the Johns Hopkins University. The experimental results thus accumulated seem to throw considerable additional light upon the variations in color and specific gravity of petroleum, as found in different parts of the world, and also upon the variations in chemical composition. Therefore, it seems as if a, summary of the evidence thus obtained might be of value to those members of the Institute who are interested in the examination of oil-fields. The summary is here presented for that purpose. The phenomenon has often been observed in many oil-fields that oils of different color, specific gravity, and chemical composition may be found within short distances of each other. A conspicuous example of this is the occurrence at Jennings, Welsh, and Anse la Butte, La., of petroleum chemically somewhat similar to Russian petroleum; that is, characterized by the presence of naphthenes. Another characteristic is the presence of considerable percentages of asphaltic compounds, sufficient in quantity to disguise the presence of solid paraffin wax, and perhaps also to render that paraffin wax more soluble * Published by permission of the Director of the United States Geological Survey. 1 Proceedings of the American Philosophical Society of Philadelphia, vol. xxxvi., No. 154, pp. 112 to 115 (January, 1897).

Jun 1, 1910

By Henry S. Drinker

(Canal Zone Meeting, November, 1910.) FEW men reach middle life without having had the experience of failure in one or more undertakings; and most of us can look back with gratitude to help or advice given us by friends at critical periods of our lives. If, as men, we ask and take the benefit of such aid, why should we expect our sons to be stronger? A parent can make no greater mistake than to send a boy, however steady and intelligent he may be, off' to school or college, and expect the boy always to cope successfully with all the new conditions and new difficulties that may confront him. This is undoubtedly more the case with a freshman, in his first year at college, than in later years, or than it is with a boy at day- or boarding-school, where the boy receives a greater degree of care and oversight than can be given to the young man entering college; of all periods in life, the youth in his freshman year-fresh from the overshadowing care of home and school-may need judicious advice and timely aid. The change from the restraint of home and school to the freedom of college life is sudden and marked, and it is in this the first year of the boy or young man of 17, 18, or 19 years of age, that some tactful, judicious aid should be near him in his work and course. Some boys go to college so well prepared that they become careless and finally fall behind in their work from over-confidence. Others meet trouble from ambitiously trying to do more than their previous preparation, or physical or mental strength, can sustain. Others fall behind from illness-from injuries-from natural inability to grasp at first, without more aid than comes to them in the regular course of instruction, the higher mathematics-or mayhap the modern languages, or other subjects presented by the advanced curriculum of the present day. When a boy or youth begins to

Jan 1, 1911

By A Audétat, W T. Li

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Middle and Lower Yangtze River metallogenic belt is one of the most important polymetallic resource areas in China. Iron oxide-apatite deposits, mainly distributed in Ningwu and Luzong volcanic basins, are a distinct type of iron deposits in this region. These deposits have a close temporal and spatial relationship with Mesozoic dioritic porphyries and are characterised by magnetite-apatite-pyroxene/actinolite ± anhydrite assemblage and large-scale sodic-calcic alteration.Widespread multiphase inclusions in pre- to main-mineralisation stage pyroxene and garnet in Meishan (in the Ningwu basin), Luohe and Nihe (both in the Luzong basin) iron deposits were trapped at ~780°C in extremely saline brines (~90 wt per cent NaCl equivalent), consisting of Na (13–24 wt per cent), K (7–11 wt per cent), Ca (~7 wt per cent), Fe (~2 wt per cent), Cl (19–47 wt per cent) and SO4 (3–39 wt per cent), based on petrologic, microthermometric, Raman spectroscopic studies and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses of natural fluid inclusions and synthetic analogues. The high Cl/Br, Na/B and S/B ratios in brine inclusions and the heavy sulfur isotopic values of anhydrite and pyrite (d34SAnh = +15.2 to +16.9‰, d34SPy = +4.6 to +12.1‰) suggest a significant contribution from both halite- and anhydrite-bearing sedimentary rocks. The involvement of evaporites caused the production of large amounts of high-salinity brines with apparently enhanced capacity to extract iron from the dioritic intrusions.According to their geologic features and the above characteristics, these iron oxide-apatite deposits are considered to be a special type of iron oxide copper gold (IOCG) deposits characterised by high contents of Na, Ca, Cl and SO4 in the ore-forming fluids. Moreover, we believe that evaporite-bearing sedimentary basins are more prospective than evaporite-free ones for these kinds of deposits.CITATION:Li, W T, Audétat, A and Zhang, J, 2015. The connection between evaporites and iron oxide-apatite deposits, Yangtze River, China – laser ablation inductively coupled plasma mass spectrometry analysis of Na, S, Cl and Br in fluid inclusions, in Proceedings PACRIM 2015 Congress, pp 623–630 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Stainier X.

The connexion between the Kent and the Continental coalfields on the one hand and the western British coalfields on the other has been for many years a controversial subject between geologists. These coalfields were once considered as detached portions of a former extensive sheet of Carboniferous deposits, but some geologists seem now to incline to the view that they were never connected. The writer hopes to show that the problem is one of the most difficult of geological investigations; that we are still far from a perfect solution; and that both of the extreme theories must be set aside. The physiography of NW Europe during the Carboniferous, with its various generations of earlier folds, is outlined and the features of the Lower and Upper Carboniferous anticlines and synclines discussed, followed by consideration of the denudation of the coalfields and local descriptions of the Malvernian range and Usk anticline, the Pennine chain, the Shropshire coalfield and the Kent coalfield. An attempt is made to trace the transverse Midland anticlines southwards and to deal with the intervening syncline: for example, if the dissymmetrical profile of the Pennine Chain holds good at its southern end then the syncline west of the chain must be deeper than the syncline east of it (the Kent syncline), and in this syncline the deepest part must be at its south-eastern corner, and therefore south of the diagonal ridge. T here is some actual evidence of the existence of Coal-Measures in this syncline, as the results of the Batsford and Burford borings prove. The hypothetical character of most of the conclusions will prove, beyond any doubt, how fa r geologists still are from a perfect settlement of this problem, and how much this settlement is dependent on the more or less advanced state of knowledge regarding all the geological features of these coalfields and of the surrounding country

Dec 1, 1916

By I Gray

This paper examines the effects of the changes in stress that a coal may undergo as part of the drainage process. As a consequence of this, some coal seams will come to the situation that they have zero horizontal stress existing within them at the time of mining. The hypothesis of this paper is that this lack of horizontal confining stress means that on mining, the vertical stresses may be easily raised to a level where failure occurs. This failure may be accompanied by significant energy release from energy stored within the coal as well as that coming from the roof and floor. To determine the state of stress within the coal seam, the concept of the effective stress path that the coal passes through is examined and is found to be very dependent on the shrinkage of the coal with degassing, the Young’s modulus of the coal and its Poisson’s ratio. The Young’s modulus of the coal is important and has been found to be highly dependent on the state of stress within the coal. It may change by more than an order of magnitude.CITATION:Gray, I, 2014. The consequences for pillar stability of zero confining stress brought about by forced or natural drainage, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 331–336 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By Edward W. Parker

IF one is to place any credence at all in the reports published in the daily press, the subject of conservation has been a very lively topic of conversation during the past 60 days, and it does not appear that the temperature of the summer months has been in any way moderated by the discussion. It is a subject in which we are all vitally interested and to which, so far as our mineral resources are concerned, both the Institute and the Geological Survey have liberally contributed. The report of the National Conservation Commission, appointed by President Roosevelt, contains a series of papers on the conservation of mineral resources, all of which were prepared by members of the Geological Survey and were compiled largely from information previously collected by that Federal bureau in the performance of its regular duties. It is not the purpose of this paper to reiterate in extenso any of the material already published. The contributions of the Survey officials to the Commission's report have been published in a separate document as Bulletin No. 394. This docunient is for free distribution and may be obtained upon application to the Director of the Survey. In the preparation of this paper I desire merely to make a few suggestions regarding the possible necessity of some restraint upon or control of one branch of the mining industry with which I have been somewhat closely associated for the past 20 years-that of coal. Most of the members of the Institute are cognizant of the suits brought by the government against the anthracite-operators in Pennsylvania, or the combination of interests commonly known as the ? hard-coal trust." No defense of any illegal combination in restraint of trade is intended, but there are some facts which should not be lost sight of, and unfortu-\

Nov 1, 1909

By Ruddle R. W.

The slags produced in copper smelting are largely composed of silica and ferrous oxide and may therefore be regarded as essentially ferrous silicates. A fair amount of information is available on the constitutions of the liquid slags used in copper smelting and, in this connection, the large volume of work being carried out on steelmaking slags should be helpful. Constitutional diagrams are available for most of the principal systems involved (SiO2-FeO; SiO2-FeO-Al2O 3; SiO2-FeO-CaO; SiO2-FeO- MgO; and SiO2-FeO-CaO-Al2O3) and these show that additions of Al2O3 and CaO reduce the freezing points of SiO2-FeO slags but that additions of MgO increase the freezing point. A certain amount of information is available on the thermodynamics of slags, but much further work on this subject is required. Modern theories of the constitution of liquid slags deny the existence of molecular compounds but consider that liquid slags are mixtures of various ions such as, Fe2+. O2- and SiO4(4-). Little appears to be known of the reactions between matte and minor constituents dissolved in the slag

Jan 1, 1953

By Ivan E. Goodner, Charles H. Fulton

THE subject of the constitution of copper-iron mattes has received considerable attention in recent years by Keller,1 Bolles,2 Hofman,3 and Gibb and Philp.4 Still more recently Friedrich, Röntgen, Wiedmann, Heyn and Bauer, and Leroux have published, in some instances, elaborate researches on the various systems of the sulphides, and the sulphides and their respective metals, which enter into the constitution of mattes, and have added very greatly to the knowledge of the subject. The work of Friedrich has been especially fruitful. But to date no effort has been made to correlate the data obtained in the latter researches and apply then to the study of the product called " matte," which is made in such large quantities by copper and lead-smelters. In this paper we propose to determine, by metallographic and chemical means, the constitution of copper-iron and copper-lead mattes in the light of the recent data above mentioned. We do not discuss copper-nickel mattes or speisses (artificial arsenides). The paper is divided into three sections I. A review and discussion of the various binary systems of the metallic, sulphides, and the binary systems of various metals and their respective sulphides entering into the constitution of mattes; also a discussion of the physical and chemical properties of these sulphides. II. A description of the results obtained from the chemical and metallographic examinations of the samples of copper-iron and copper-lead-iron matte obtained from various plants.

Nov 1, 1908

By W. S. CAYPLESS, H. O. Hofman, E. E. HARRINGTON

1. INTRODUCTION. AT the Lake Superior meeting, September, 1904, Messrs. A. Gibb and R. C. Philp presented a paper entitled " The Constitution of Mattes Produced in Copper Smelting,)' in which they concluded that ferrous and cuprous sulphides formed the chemical compound, 5 Cu2S, fee. They arrived at this inference from the observed fact that a matte containing Cu2S, 90.4, and Fee, 9.6 per cent (or, in round figures, Cu2S, 90, and Fee, 10 per cent.), did not contain any metallic copper, while one with more than 10 per cent of FeS readily dissolved copper, and with less than this amount retained copper in mechanical suspension. Although they determined the melting-points of five mattes containing from 32.6 to 80.1 per cent of copper, they did not draw a freezing-point curve, as the necessary apparatus was not available. A microscopical examination of 11 polished samples, gave them a grayish-black field of very uniform appearance, except that 5 of the specimens showed the presence of metallic copper. The object of the present investigation was to supplement the above paper by drawing the freezing-point curve of the series ferrous sulphide cuprous sulphide, and to see how the constitution could be further, revealed by microscopical work. The results obtained lead to conclusions very different from those of Gibb and Philp. While their paper bears the date 1904, it was published only in 1906.2 In the meantime, Bolles3 had presented his paper, "The Concentration of Gold and Silver in Iron Bottoms." The raw material which formed the basis of the research was a matte containing Fe, 61.68, and Cu, 11.20

Jan 1, 1907

By Albert Sauveur

IT is not without some hesitation, and even misgiving, that I venture into a discussion of the now classical Roberts-Austen Roozeboom diagram, lest I too fail, like so many other writers, in giving a satisfactory and logical explanation of these interesting curves. Roozeboom's original diagram is reproduced in Fig. 1. The generally accepted meaning of the various curves has been so often described before this Institute that it will suffice to recall it briefly before passing to my own interpretation of the changes involved.

Nov 1, 1906

By Ruddle R. W.

Solid mattes are generally held to be either (a) eutectiferous mixtures of the component sulphides Cu2S and FeS or (b) mixtures of complex sulphides. This chapter shows that liquid mattes consist essentially of a homogeneous phase in which iron, copper and sulphur are present. The amount of sulphur is generally less than that required to account for all the metals as stoichiometric sulphides; mattes cannot therefore be regarded as mixtures of FeS and Cu2S. Some iron oxide may be dissolved in the sulphide phase and magnetite is often present as a second phase. If the sulphur content of the matte is reduced the composition enters the miscibility gap in the ternary system and either an iron- or copper-rich solution (depending upon the composition of the matte) separates as a new phase. On solidification any one of four phases (iron, copper, Cu2S and FeS solid solutions) may crystallize as primaries. The remainder of the matte solidifies as a ternary eutectic. It is possible that iron oxides enter into this eutectic. Knowledge of the ternary Cu-Fe-S system is far from complete and nothing is known of the quaternary system Cu-Fe-S-O

Jan 1, 1953