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By T. Y. Chong, J. A. Folinsbee

Since milling began in 1909, the PJV Dome mill has been expanded several times, to the current throughput of 11,500 tonnes per day. PJV recovers free gold using crushing and grinding followed by gravity concentration. The remaining gold in the gravity tails is recovered by cyanide leaching followed by Carbon-In -Pulp processing. Prior to 1993, cyanide tailings were impounded in the tailings pond where cyanide was allowed to degrade naturally. Effluent was discharged seasonally during the summer and early autumn to maintain the water balance. In 1993, an Effluent Treatment Plant (ETP) was designed and constructed for the purpose of removing dissolved metals and suspended solids. In 1997, an INCO SO2/Air cyanide destruction process was added to the ETP. Even though the ETP was successful in meeting the cyanide, metals and total suspended solids (TSS) discharge limits, often the treated effluent failed to pass toxicity tests. Following successful laboratory and plant scale testing, the addition of the chelant EDTA (ethylene diamine-tetra-acetic-acid) was commenced in the 1999 operating season. To date, discharged effluent has passed all toxicity tests. This paper describes the evolution of the ETP from its early conception to the various phases of upgrade needed to meet the MISA discharge limits.

Jan 1, 2005

By C. Lapointe

"IntroductionTen years ago, when nuclear fission became practical, the element uranium, until then a not very desirable by-.product of the radium industry, became overnight the strategic material par excellence. One of the several important problems that had to be solved at that time was the rapid and precise determination of uranium in ores and concentrates.GeneralThe chemical analysis of uranium ores is a long and difficult business and is complicated by the presence in most ores of a large number of interfering elements. True, much progress has been made, during the past few years, toward simplification of the analytical methods, but the chemical determination still remains the job of a skilled operator. For this reason, the chemical method has been replaced, whenever possible, by a physical determination based on the measurement of the radiations emitted by the elements of the uranium family. There are several types of instruments suitable for these measurements, but of all the radiation detectors known to the physicist, such as ionization chambers, crystal detectors, scintillation, proportional counters, and the like, the Geiger-Mueller counters have proved to be the most satisfactory for routine determinations, because of their simplicity.The Geiger-Mueller counter is a very versatile instrument; it can be constructed to detect any type of radiation, corpuscular -0r electromagnetic. Here, however, we are interested in these counters because of their ability to detect the beta and the gamma radiations, both emitted by some members of the uranium family. The beta radiation is corpuscular, and is composed of fast electrons, while the gamma radiation is electromagnetic."

Jan 1, 1950

By Amin Saravari, Jamal Jafari, Abbas Sam

"The fourth concentrate production plant includes the comminution systems and the medium-low intensity magnetic separators (LIMS). Based on different conditions, two types of materials are fed into the plant. Type A: 70% of mine ore and 30% of reject materials from magnetite plant and type B: 100% of mine ore. The goal of the present study was to increase the iron grade and the blain number with low sulfur content in final concentrate as the pellet feed. An appropriate pellet feed should have more than 67% of iron, less than 0.1% of sulfur and a Blain number of more than 1800 cm2/g. The Fe, S and Blain no. amounts for the present concentrate are 66.6%, 0.95%, and 500 cm2/g (feed type:A) and 67.8%, 2.3%, and 450 cm2/g (feed type: B), respectively. In this research, the plant improvement efficiency was evaluated by changing the feed particle size distribution and using the flotation system. Laboratory experiments were designed based on the three circuits:1) LIMS (Low Intensity Grinding Rolls) feed grinding-LIMS test-flotation test2) LIMS feed grinding-flotation test-LIMS test3) LIMS concentrate grinding-flotation testThe best results were obtained using the first circuit at the LIMS feed size (d80) of 132 ?m. The processing results using the circuit no. 1 (feed type: A), showed a LIMS concentrate with 69.8% of Fe and 0.36% of sulfur. In this case, the final concentrate (after flotation) with Fe grade of 70.3%, sulfur content of 0.07% and Blain no. of 1571 cm2/g were obtained. In case of the feed type of B, the LIMS concentrate with Fe grade of 68.7%, and sulfur grade of 1.6% was achieved. Also, the Fe and sulfur contents were 69.3%, and 0.4% respectively with a Blain number of 1112 cm2/g. According to the obtained results, it was suggested that a LIMS feed comminution along with a LIMS and flotation systems are necessary to achieve an appropriate iron and sulfur grades with an acceptable blain number. To reach a concentrate Blain number as a pelletizing feed, a High Pressure Grinding Rolls (HPGR) system at the end of the processing line was recommended."

Jan 1, 2016

By Jack G. Hazan

The Critical Path Method is the modern scientific answer for solving the planning and scheduling problems inherent in today's complex projects. With this method, nothing is left to chance. All resources are controlled and kept to the minimum. The various phases are properly planned and strategically determined. Optimum conditions are evaluated for the most economical and fastest way to complete a definite project. The method must be fully understood and implemented with positive data and continuous feedback to obtain the best results. This paper covers the various aspects of the Critical Path Method and mentions some of its applications in the mining and metallurgical fields. T 0 progress to a higher state of human welfare necessarily involves sacrifices. The greatest sacrifice is to relinquish social freedom in favour of economic freedom. In the old days, for example, a cobbler was free to work at whatever time of the day he chose; today, he can't. He is now forced to adapt himself to environment and to work at stand-

Jan 1, 1965

By J. E. Nesset, J. A. Finch, Rosenblum. F., S. Somot

"In a previous presentation at the CMP, evidence was shown for the formation of hydrogen sulphide (H2S) in self-heating experiments on pyrrhotite-rich samples (Somot and Finch, 2006). Oxidation of H2S is strongly exothermic leading to the proposition that H2S is playing a key role in the self-heating process. Subsequently, tests in two weathering apparatus (I and II) were run under varying oxygen levels to further examine conditions leading to self-heating. To characterise their resulting self-heating capacity the samples from the weathering tests were subjected to a modified Stage B test using the self-heating apparatus developed by Rosenblum and co-workers (Rosenblum and Spira, 1995; Rosenblum et al., 2001). Results showed highest self-heating after weathering occurs under low oxygen conditions, supporting the H2S hypothesis. It was observed that highest heating rates are not directly related to highest weight gains of samples.INTRODUCTION“Sulphides” refer to several types of minerals containing sulphur in its lowest oxidation state of - 2. Self-heating is the spontaneous heating of a material without external heat input. It is well established that some sulphides will self-heat on exposure to moisture and oxygen (Farnsworth, 1977; Good, 1977; Rosenblum et al., 2001; Wu and Li, 2005). This process is highly exothermic and if the heat generated is not dissipated, combustion may occur when the temperature reaches the ignition point of the sulphide (typically 350-400 °C). The hazards of sulphide self-heating range from handling hot material, to sulphur dioxide release, to fires. The literature documents self-heating incidents underground, on ships and trucks transporting sulphide concentrates, and in mine waste (tailing) disposal areas (Stachulak, 1990; Lukaszewski, 1969; Headley et al., 1977). Lukaszewski (1969), Farnsworth (1977), and Good (1977) note that sulphide minerals can act as fuel to promote underground mine fires. Based on such findings, sulphide minerals could become classified as hazardous materials, making transport of concentrates and storage of mine waste subject to stricter and more costly regulation. The problem is one the industry is keen to avoid."

Jan 1, 2009

By Iain Sommerville, Hugh Mountford, Dawid D. Smith, Claude Dube, Brett Hixson

JW Aluminum use lean and Six Sigma techniques to continuously improve their target of reliable, repeatable and reproducible (3R) manufacturing. Six Sigma’s second stage gate, known as "Measure" involves identification and qualifying appropriate measuring systems. Metal quality (inclusions) are known in the industry to be an important element in 3R casting. The measurement of inclusions at JW Aluminum historically depended on outside vendors. In order to establish real time inclusion measurement ability within JW Aluminum, inclusion measurement systems in the marketplace were investigated. The qualification of a MetalVision MV20/20 ultrasonic inclusion analyzer are discussed as well as the subsequent application of the system in melting and casting improvement projects.

Jan 1, 2015

By W. G. Millar

Until a fire occurs, insurance and prevention work are often looked on as unavoidable necessities, but as insurance is back of all business credit, it is essential to know that in case of damage money will be available to cover the loss; while the interruption of production, often caused by a fire, brings home the realization that if prevention work avoids such an interruption, it is well worth while. Fire insurance is a legal contract guaranteeing the payment of large amounts to an owner, but it is possible there is no other important contract that receives so little consideration. Although previously carried on elsewhere, it is only of recent years that insurance engineering has been actively followed up in Canada, with inspections of an owner's property carried out for his benefit. Now inspections of this kind are made, advice on fire prevention and protection work ?is available, reports with recommendations with regard to the above are furnished periodically, and with this method applied the owner receives the broadest possible cover and security at the lowest cost. Rates are set by the underwriters by rating schedules which charge for defects in a building and allow credits for protection and other favourable features . These schedules are based on the past record of loss of mining properties as a class, so that a fire in another mining property indirectly affects you, but the amount paid is reduced in proportion as your property is improved. The writer feels, from personal experience, that there is no industry where fire prevention receives more attention than the mining industry, and it is a pleasure to advise that, due to this co-operation, some reduction in the basis rates for mining risks is now being made by the underwriters.

Jan 1, 1928

By H. H. Bleakney

THIS paper presents evidence that in 3 1/2% nickel steel, the published temperature for the Ac1 transformation, l,275°F., represents the completion of that transformation, and that its inception occurs approximately 275°F. lower, at about l,000°F. The formation of austenite within this range, especially at the higher temperatures, and its subsequent decomposition to martensite, results in considerable impairment of the properties of the steel. That the solid solution found to occur below l,275°F. is austenite has been questioned, but the evidence herewith presented, while not decisive, appears to be reasonably convincing. INTRODUCTION The February, 1939, issue of Metals Technology contains a very interesting paper by I. N. Zavarine, Associate Professor of Metallurgical Engineering at the Massachusetts Institute of Technology. In that paper, Professor Zavarine presented photomicrographs illustrative of the microstructures produced by heating nickel steels to a temperature slightly below the carbon change point, and holding them at that temperature for various lengths of time. His illustrations show that the structures found after such treatment do not consist merely of ferrite and carbides, but are characterized by the presence of a third phase, which he describes as a' 'sub-critical solid solution'. The occurrence of this third phase in increasing amounts is accompanied by an increase in strength and a loss of ductility and impairment of elastic ratio of the steel. Some years ago, one of the authors encountered the above-mentioned phenomenon in treating large forgings of 3.5% nickel steel. After normalizing and then drawing at l,250°F., very poor mechanical properties were obtained. Investigation of the steel disclosed no inferiority in quality. Eventually, after considerable waste of time and money, a draw temperature of l,150°F. was tried. This treatment resulted in a very great increase in elastic ratio, over 5 per cent increase in percentage elongation, and proportionate improvement in reduction of area.

Jan 1, 1941

By M. Kunst

The creep behavior of three AJ62 alloys was investigated in a wide range of stresses and temperatures. Multi-level tensile creep tests revealed a distinct primary creep stage and a high stress exponent up to a value of 10. The threshold stress concept which is commonly used in combination with high stress exponents was utilized in the analysis of creep behaviour. This resulted in an effective stress exponent for the AJ alloys indi¬cating dislocation climb as the dominating creep mechanism. In addition, microstructural observations of the lamellar eutectic and of the a-Mg-matrix were carried out using opti¬cal microscopy, SEM and TEM. The creep properties of the alloys are discussed in the context of microstructural parameters such as phase volume-fraction, stability and solute supersaturation.

Jan 1, 2006

By Esau Arinaitwe

The most extensively used methods and approaches for characterizing and selecting frothers for plant application are based on measurements in clean water in the absence of solids and without consideration of physicochemical factors that are known to influence the properties and behavior of practical flotation froths, and hence metallurgical performance. These factors include aquatic chemistry, collectors, modifiers, particle shape and size, and pH. Understanding interactions between these factors and the role and relevance that they play in characterizing frothers and froth zone properties will greatly aid in the frother selection and evaluation process. Such an understanding will also greatly enhance the ability to create frother solutions that are sufficiently robust to plant variability (such as mineralogical, comminution, operational, physical and chemical). This paper reports results of a “systems approach” study designed to probe ways in which physicochemical factors a) influence frothing and bubble size in 2- and 3-phase systems, and b) confound correlation of fundamental measurements with flotation outcome. The concepts and insights gleaned from fundamental frother studies, together with empirical laboratory flotation tests and a thorough understanding of plant needs and challenges were used to develop and implement customized frother formulation at a Cu-Mo flotation plant. Plant metallurgical data and qualitative assessment of froth zone properties showed that a frother formulation developed using the approach described here provided marked improvements in froth characteristics (mineralization, mobility, stability, persistence). These improvements resulted in better circuit control and significant performance advantages, such as improved coarse particle recovery, without detrimental downstream effects. INTRODUCTION Successful recovery of value minerals of sufficient grade via the flotation process requires selective manipulation of the value minerals to render them hydrophobic using collectors and modifiers. The hydrophobized minerals then attach to air bubbles and the mineral-bubble aggregates are selectively transported through the froth zone into the launder. Frothers play a critical role in froth formation and more importantly in achieving and maintaining desirable froth characteristics (for example, stability, mobility, persistence) that are essential in facilitating the selective transport and recovery of value minerals. Fundamentally, frothers contribute to the transient stability of thin liquid films and so aid in reducing bubble coalescence rates in the pulp and froth zones, thus maintaining the small bubbles required for efficient bubble-particle attachment. Invariably, the action of frothers at the liquid/gas interface in the pulp and froth zones impacts bubble stability, water and solids transport to the froth, which in turn impacts froth mobility, froth carrying capacity, and the concentrate grade. Consequently, selection and evaluation of frothers for flotation plants requires careful consideration of the frother type, though the choice is limited to only two main classes of compounds in terms of fundamental chemistry (short chain alcohols and polyglycols). Even with the selection of what is thought to be the best frother for a given application, practical knowledge of the froth zone and experience in controlling its properties is essential for maximizing metallurgical performance.

Jan 1, 2019

1. Scientific prospecting has had a profound and some-what unexpected effect on the world's supply of raw materials over the past twenty years. Where shortages were recently anticipated, abundance now prevails. It seems probable that, for the foreseeable future, adequate metallic resources will be found at costs well within the world's economic means. 2. The amount of research devoted to scientific prospecting has been extremely small in relation to the possible importance of the problem and to what could be done. It has been dominated by the thought of a dozen brilliant men, and true research expenditures have not amounted to more than a few million dollars. 3. An undue proportion of the expenditures have been for so-called geological research -mostly of a petrologial character. The results have essentially been of historic interest only. However, there has been some in-crease in genetic understanding, and this is of great importance for future resources. 4. Basic advances in mineral exploration have been made in detection techniques, generally called geophysics and geochemistry.

Jan 1, 1964

By Garry Johansen, Andrew McCallum, Sandy Gray, Gary Patrick, Jennifer Abols

"The authors challenge the traditional thinking that whole ore cyanidation followed by Carbon in Pulp (CIP) or Carbon in Leach (CIL) should be applied as a standard process in the majority of gold processing flowsheets. The concept of whole ore leaching by using cyanide can result in unnecessary environmental and capital risk. Alternative, currently available technologies can be used to provide the desired level of gold recovery at a much lower installed cost and less impact on the environment. Gravity concentration, alone or in conjunction with flotation, can produce a gold bearing concentrate that can then be fed directly to a batch or continuous intensive cyanidation unit.The InLine Leach Reactor (ILR) is an intensive cyanidation unit developed by Gekko Systems of Australia. Advantages of this technology include significantly reduced capital outlays for greenfield plants or plant upgrades and increased investor returns. Reduction of onsite cyanide and carbon inventories improves plant safety, materials handling and site security. By using direct electrowinning to treat the gold bearing solutions produced by the ILR, the need for a conventional carbon stripping circuit is removed. Potential also exists to increase grind size – saving energy, further reducing capital and operating costs and decreasing the environmental impact of a mill. Detoxification of cyanide before the release of solution to the tailings dam can minimise tailings disposal and containment requirements.When used in the right application the proposed process will have little or no impact on gold recovery and may actually increase recovery for complex ores. Areas applicable to this type of treatment include: plants in environmentally sensitive regions, lower tonnage higher grade deposits, coarse gold deposits, and preg robbing ores - some of which may not currently be economically feasible using standard processes and flowsheets. We have provided three examples of such projects, where an alternative to whole ore leach and CIP or CIL has delivered these benefits."

Jan 1, 2003

By John Knox

The object of this paper is to present an analysis of the major problems encountered both in the design and application of downhole drills. Particular reference is made to design features governed by: physical size limitations; metallurgical material standards; physical operating environment; range of commercial materials to be drilled; high power output required, coupled with simplicity from the operating and maintenance viewpoint; and bit design. The history of attempts to develop downhole drills is discussed, and representative mechanical configurations are illustrated. The general design and application aspects of the different types are commented on. The application of this drill type in various commercial fields, such as (a) oil-well drilling, (b) open-pit mining and (c) underground mining, is discussed, along with the limitations presently imposed by the commercial state of the art in the manufacture of accessory equipment; e.g., drill rods, air compressors, mountings, etc. Suggestions on the possible future direction of the development and application of this tool are put forth.

Jan 1, 1965

By I. Farr, M. R. Mock, J. C. Robison

"HPAL and POX autoclave vapor-space gasses are vented through an autoclave PCV (Pressure Control Valve). The downstream steam-born mist of liquid droplets and solid particles travels in excess of 1000 m/s with megawatts of kinetic power at temperatures up to 160 C. The characteristics of downstream states often result in problems with corrosion, erosion, noise and vibration. Comprehension of those and related characteristics aids in improved pressure control, overpressure control and autoclave level control. We introduce compressible multiphase flow concepts and constructs germane to such flow including choked flow, continuous phase change, shock waves and supersonic flow plumes. Flow modeling based on first principles quantitatively predicts such flows providing a tool for component sizing and a method to estimate effects of water injection on flow. Insight deduced from modeling aids in mitigation of afore mentioned problems of which we share some from-site examples.INTRODUCTION First principles related to fluid thermodynamics and compressible flow have been employed akin to their application in the rocket industry. We will present the results of the application of those principles conceptually and authentically without mathematical rigour while using language of the pertinent disciplines. The autoclave (AC) vapor space over the slurry of a POX (Pressure Oxidation) or HPAL (High-Pressure Acid Leach) system (depicted in Figure 1) is vented via a PCV (pressure control valve) followed by certain ducting, and perhaps a nozzle, before exiting at atmospheric (typically) pressure. As indicated by its name the PCV controls the AC pressure as the flow control component of a pressure control loop."

Jan 1, 2017

By T. A. Lazier, C. S. Longley

"Paymaster Consolidated Mines, Limited, owns several groups of claims in various parts of the Porcupine district. The area in which mining has been carried on includes parts of lots 5, 6, and 7, con. 1, Tisdale township, and twelve adjoining claims in Deloro township to the south. Highway No. 67A between South Porcupine and Timmins crosses the property.The discovery of the Dome mine in 1909 caused a rush of prospectors to the district and in a few weeks practically all territory adjacent to the Dome was staked. At that time work was started on the West Dome, West Dome Lake, Apex, and Standard properties. These were consolidated in 1930 to form the present Company. Gold was produced from the West Dome Lake from 1915 to 1930, and from the Standard-Paymaster from 1922 to 1928. The total production of the previous and present companies from 1915 to November 30, 1946, has been 487,170 oz. gold and 149,342 oz. silver from 2,337,554 tons of ore."

Jan 1, 1954

By K. W. Fritzsche

The prosperity of any nation depends, to a large extent, on its natural resources such as oil, coal, 'metal, timber, waterpower, and fertile soil. Each one of these resources forms the basis of a huge industry. The mining and smelting industry ranks among the first since it paves the way for a number of other industries. The mines and smelters provide a market for electric power, coal, timber, and agricultural products: other industries in turn provide a market for metals and non-metals. The real pioneering, however, is done by the prospector who goes into the wilderness to search for the ores from which the metals are to be extracted for the use of men. Prospecting is an interesting and fascinating occupation. There are many difficulties and hardships in the way but the lure of gold and the vision of finding an outcrop that may develop into a large bank account, within a reasonably short time, will urge the prospector forward. Thus, on the outskirts of this northern hemisphere hundreds of prospectors are searching and toiling and of whom nothing is known or heard until they reach civilization and announce a new discovery. Then a mad rush takes place and everybody who can afford to go will take a gamblers chance and plant stakes in the neighbourhood of the new discovery, or wherever an outcrop of mineralized rock can be found, with the hope of winning a fortune.

Jan 1, 1925

By Julian V. Simela

Conventional methods of underground surveying use theodolites/total stations and 3D laser scanners to obtain information about the underground environment. Current methods of geo-referencing these instruments to a mine reference system include triangulation, trilateration and resection. However, despite technological advancements, surveying procedures have remained slow, laborious and relatively unchanged during the last half-century. Recent innovations in the robotics community have shown that automated mapping of underground mining tunnels can be undertaken using 2D/3D laser scanners. These techniques have the potential to, in turn, improve upon current underground surveying and mapping methods. Automating surveying and mapping using current surveying tools without changing the setting up procedures or removing current constraints, or even changing the type of equipment used, does not change the status quo. The problem of moving from a static, tripod based surveying and mapping system to an unconstrained mobile surveying and mapping system is the subject of this paper. A current challenge for automated mapping is the ability to automatically geo-reference a mobile mapping system to a mine reference system. For a mobile mapping system that uses a horizontally mounted 2D laser scanner to gather data of the underground environment, the challenge of determining its position and orientation within the mine environment is magnified even more. This paper introduces Mobile Automated Scanner Triangulateration (MAST), a technique under development at Queen?s that is designed to geo-reference a mobile mapping system to a mine reference system for the purposes of underground mine surveying. MAST quickly and automatically determines scanner 2D position and orientation (azimuth) in a mine reference frame by using minimal human input.

Aug 1, 2013

By E. Özberk

Uranium minerals are often associated with iron minerals, and during the hydrometallurgical processing of the uranium ores, iron plays several significant roles. The presence of Fe(III) in solution promotes the oxidative acid leaching for the recovery of uranium. The control of the distribution of impurities in milling and refining is also affected by dissolved iron. When rejected from the process streams, iron usually collects other impurities and contributes to the stabilization of the wastes for final disposal. These roles of iron, as they relate to current uranium processing operations, are discussed in detail, and some broad and historical perspectives are also presented.

Jan 1, 2006

By F. J. Hrach, S. A. Gasiorowski, J. D. Bittner

"Separation Technologies, LLC (ST) has developed a processing system based on triboelectric charging and electrostatic separation that provides the mineral processing industry a means to beneficiate fine materials with an entirely dry technology. In contrast to the other available electrostatic separation processes that are typically limited to particles greater than 75 µm in size, the ST belt separator is ideally suited for separation of very fine (<1 µm) to moderately coarse (500 µm) materials with very high throughputs.. The technology has been also successfully applied to the beneficiation of a variety of minerals including calcium carbonates, talc, and potash. TECHNOLOGY OVERVIEWThe ST separator utilizes electrical charge differences between materials produced by surface contact or triboelectric charging. When two materials are in contact, material with a higher affinity for electrons gains electrons and thus charges negative, while material with lower electron affinity charges positive. This contact exchange of charge is universally observed for all materials, at times causing electrostatic nuisances that are a problem in some industries. Electron affinity is dependent on the chemical composition of the particle surface and will result in substantial differential charging of materials in a mixture of discrete particles of different composition.In the ST separator (Figures 1 and 2), material is fed into the thin gap 0.9 – 1.5 cm (0.35 -0.6 in.) between two parallel planar electrodes. The particles are triboelectrically charged by interparticle contact. For example, in the case of coal combustion fly ash, a mixture of carbon particles and mineral particles, the positively charged carbon and the negatively charged mineral are attracted to opposite electrodes. The particles are then swept up by a continuous moving open-mesh belt and conveyed in opposite directions. The belt moves the particles adjacent to each electrode toward opposite ends of the separator. The electric field need only move the particles a tiny fraction of a centimeter to move a particle from a left-moving to a right-moving stream. The counter current flow of the separating particles and continual triboelectric charging by carbon-mineral collisions provides for a multistage separation and results in excellent purity and recovery in a single-pass unit. The high belt speed also enables very high throughputs, up to 40 tonnes per hour on a single separator. By controlling various process parameters, such as belt speed, feed point, electrode gap and feed rate, the ST process produces low carbon fly ash at carbon contents of 2 % ± 0.5% from feed fly ashes ranging in carbon from 4% to over 30%."

Jan 1, 2012

By R. J. Traill

Introduction Following the discovery of high-grade deposits of pitchblende in the Great Bear Lake area of the Northwest Territories by Mr. Gilbert LaBine in May, 1930, samples were submitted to the Mines Branch for examination and investigation as to suitable methods of treatment (1). The purpose of this paper is to present, briefly, the results of the investigative work conducted on the ores and an outline of the methods developed for the extraction of the radium content and recovery of the by-products. The paper is presented in two parts. Part I gives a review of the history of radium production and of the principal processes used in other countries. Part II describes the work and gives the results of the Mines Branch investigation. Part 1-Radium Production In Other Countries Historical Outline Uranium was discovered in 1789, and more than a century later Madame Curie, while studying the physical properties of this element, observed that the ore of uranium exhibited greater activity than the pure uranium com-pounds she had prepared and traced the cause to the presence of a new element which she named radium. Eventually, research proved radium to be a disintegration product of uranium, and always present in uranium ores.

Jan 1, 1933