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By A. Ojaghi, A. R. Mohammadi

"The Marvast monazite deposit is located 35 kilometres south - southwest of Marvast in Yazd province of Iran. A representative sample weighing approximately 10 tons was prepared to study the amenability of the ore to physical beneficiation. The size fraction of +1000 µm was removed due to low monazite content and the –1000 µm size fraction was concentrated by the gravity-classification-magnetic methods. According to the results of sample characterization, the representative sample contains 220 ppm REO that is contained in monazite. It was concentrated to 41.5% REO by the above mentioned methods. The recovery of REO in the monazite concentrate was 41.5%.INTRODUCTIONRare earth elements are critical metals in many countries (Gupta, 2005; UK Geological Survey, 2011). Increasing application of these metals in hi-tech industries and price fluctuation caused by Chinese production policy has led other countries to focus on their local resources (UK Geological Survey, 2011). In this case, Iran is not an exception.REE mineralization in Iran is mainly located in the central zone. Regarding the exploration data, these deposits are divided into two categories. The first group is iron ore deposits in which the REE are carried by phosphate minerals. The other group is placer deposits where monazite is the major mineral of the deposit. The Marvast placer deposit is one of these types of deposit (Daliran, 1990; Mokhtari, 2008; Torab, &Lehmann, 2007; Alipour, 2014)."

Jan 1, 2016

By W. G. Worcester

Generally speaking, the term 'clay' appears to convey but little to the average layman other than of a sticky substance to be rigidly avoided when making a cross-country drive in the family ark- especially so if the chains have been left behind. On the other hand, the technical ceramic; engineer, though his chariot be bogged in the self-same mud-holes, will, more than likely, be planning on ways and means for the conversion of the troublesome gumbo into paving bricks over which all might ride with pleasure and security. However, to come to the point, the term 'clay' bears much the same relation to the ceramic world that the term 'ore' does to the metallurgical; in other words, as there are many kinds of ores, so also are there many kinds of clays, and it therefore becomes necessary to classify and sub-classify them previous to a discussion of their relative values and importance. Hence, a brief digression will be made from the main topic of this paper in order to enumerate and classify a number of the more important types of clays. By so doing, the relative position of Saskatchewan clays, later discussed, will be better understood.

Jan 1, 1929

By J. A. Folinsbee, Andre Robitaille, Tony Y. Chong

"Conventional crushing and grinding is followed by gravity concentration to recover free milling gold. Refractory gold, finely disseminated within the pyrite and arsenopyrite matrix, is recovered by flotation followed by pressure oxidation, cyanidation, and cementation. Non-refractory gold is recovered by cyanidation/CIP processing.A comprehensive test program aimed at improving flotation recovery was initiated in June 1995. Plant testing indicated that flotation tails value could be significantly reduced using mechanical flotation cells. Based on these test results, a flotation circuit that incorporates one of the three existing flotation columns followed by mechanical scavenging and cleaning was developed. Detailed engineering was completed in September 1996. Construction started in February 1997 and was completed in 3 months at a cost of $3.2 million. An on-stream X-ray analyzer was installed to provide real-time arsenic and iron analyses and inferred sulphur value on some of the flotation streams.The new flotation circuit proved to be an instant success. Flotation tails values were reduced by 27%. Final tails solids and solution was reduced from 0.035 to 0 023, and 0.0014 to 0.0006 oz/ton Au, respectively. Based on a mill throughput of 1,620 stpd this decrease in tails value will result in an increased gold production of 7,500 ounces per year. The payback for the project is estimated to be around one year.This paper describes the evolution of the project from bench scale testing to commissioning. Also, the operational and economic impacts on down stream processing are highlighted"

Jan 1, 1998

By Richard R. Walker, John J. Watkins, Allen C. Amos, Matulich. Angelo

THE KIDD CREEK MINE is located within the Abitibi greenstone belt, near its west end, in an area known as the Porcupine mining camp (Fig. 5). The Abitibi belt, long known for its many major gold and base metal deposits, is the largest Archean (early Precambrian) greenstone belt within the Canadian Shield. In the Porcupine area, the greenstone belt is composed principally of Keewatin (older Archean) basic to intermediate volcanics, with subordinate felsic volcanics developed• locally. Greywacke, mainly of volcanic derivation, occurs associated with and overlying these volcanics. Timiskaming (younger Archean) sediments, principally coarse clastics, unconformably overlie the Keewatin volcanics and sediments. The reader is referred to Goodwin and Ridler (1970) •r. for a more comprehensive description of the Abitibi belt.

Jan 1, 1974

By Paul Guliov

Preliminary investigations of stone resources were conducted in the La Range, Johnson Lake-Pelican Narrows-Deschambault Lake and Creighton-Amisk Lake regions of Saskatchewan. The work identified a rich variety of accessible, attractive and technically promising stone resources. Ordovician dolomites in various combinations of red, buff, yellow, grey and purple are very dense and take a very good polish. These are classified as marbles in the industry and some rival the famous marbles of Verona, Italy. A wide variety of attractive granites have been identified. Among these is a jade green stone (charnockite) and ornamental banded granites (gneisses). A dark greenish to black stone (amphibolite) with white and red veining resembles the well-known Verde Antique variety of Vermont and Italy and surpasses it aesthetically and in engineering properties. Some of these stones have been displayed at Canadian and United States expositions where they received an enthusiastic response from the international stone industry. More detailed evaluation and test quarrying of promising deposits are required. Such work could be rewarding to the industry as some stone varieties in the province have the potential for gaining international markets.

Jan 1, 2001

By Leroy C. Stewart

Owing mainly to the use of ethylene dibromide in the production of tetraethyl lead for gasoline treatment, there has been a tremendous increase during the past decade in the demand for bromine. In the United States, production, derived mainly as a by-product from the treatment of brines from salt wells, rose steadily from about two million pounds in 1924 to nine million pounds in 1931. In 1936, production amounted to between 20 and 21 million pounds. Much of the increase during the past four or five years has been due to the operation of the Ethyl-Dow Chemical Company's plant, which extracts bromine directly from sea water. The process employed by the Ethyl-Dow Company is somewhat similar to that in use on salt-well brines at their plant at Midland, Michigan, but whereas these brines contain around 1,300 parts per million bromine, sea water contains only 65 to 70 p.p.m.-about as much as the waste effluent in the brine process. By intensive research, however, a process was developed whereby a very considerable percentage of the bromine content of sea water could be recovered, and at a satisfactory operating cost. In its essentials, the process consists in liberating the bromine from the sea water by treat-ment with chlorine, blowing the bromine out of the water by a current of air, and finally absorbing it in a solution of soda-ash.

Jan 1, 1938

By J. J. Baz-Dresch

"The Cannon Mine, a joint venture between Asamera Minerals (the operator) and Breakwater Resources, is located in the centre of Washington state at the eastern base of the Cascade Mountains. The mine complex is located three blocks south of the city limits of Wenatchee, part of an urban area with a total population of 47 000. The closest residence is 350 feet from the mine portal.The B-Neath zone is a narrow, high-grade, downward extension of the southern tail of the mine's main ore body, the B-North zone. It also underlies the northernmost portion of the B-West zone (Fig . I) . The ore is usually reasonably competent but completely surrounded by very weak rock consisting of shear zone and unsilicified sandstones and siltstones.The zone has maximum dimensions of 420 ft in thickness, 500 ft in length , and 200 ft in width . The economic reserves extend from the 70-ft elevation (elevation above sea level) to the 630-ft elevation and consist of about 1.3 million tons of geologic reserves (proven and probable) at an average grade of 0.33 ounces per ton.Acquisition and ExplorationInitial DiscoveryThe initial discovery of the B-Neath zone was made by Tenneco Minerals during July through September, 1984. Their 22-hole surface drilling program consisted of 18 200 ft of drilling. Tenneco Minerals had acquired the 91/2 acre lease from United Mining Corporation.Asamera Minerals subsequently purchased Tenneco's lease in July, 1985; Tenneco retained a royalty position which was later purchased by Echo Bay Mining.Follow-up drilling by Asamera Minerals consisted of both surface and underground drilling. Eight surface holes (7200 ft) were drilled commencing in December, 1985. Following evaluation of the geologic data, an access drift was driven on strike along the top of the ore zone on the 500 level. Diamond drilling from this platform consisted of 17 200 ft in 79 holes."

Jan 1, 1990

By P. K. Kaiser, C. D. Martin, F. Amann

"This article focuses on the uniaxial compressive strength (UCS) of homogeneous and heterogeneous rocks. Critical factors impacting the UCS of rocks are reviewed and then separate assessments of UCS data from homogeneous and heterogeneous rocks are presented. The variability (coefficient of variation) of UCS test results for homogeneous rocks is found to be generally <25% while for heterogeneous rocks the variability is >35%. Failure mode variation is found to be the cause of the variability of UCS test results in heterogeneous rocks. Empirical engineering design methods that use UCS as an input parameter are discussed and suggestions are provided for selecting appropriate UCS values.INTRODUCTIONThe UCS is one of the most commonly used rock engineering parameters whether for rock mass classification or for strength determination. The mean UCS and its variability are often assumed to represent a reliable rock material property. For the reasons discussed in this article, UCS is rarely representative of the intact rock UCS. The UCS test simply records the collapse load during uniaxial loading of a cylindrical specimen. As suggested by many, the UCS is an index rather than a unique engineering parameter. The UCS is thus a proxy for rock strength which depends on the loading rate (e.g., Bieniawski 1967), specimen geometry (e.g., Hudson et al., 1971), specimen size (e.g., Bieniawski 1968), and many other factors. Furthermore, the UCS is not the same as the Hoek-Brown strength criterion parameter sci.There are differences in opinion on what is commonly considered to be ‘intact rock’. When sampling ‘intact’ pieces of core from drillholes crossing blocks of rock bound by block forming discontinuities, samples will be ‘intact’ but some samples will be veined, others will be damaged, and others will be neither. According to Hoek (1983), intact rock pieces are “the unfractured blocks occurring between structural discontinuities in a typical rock mass” and the sci parameter for intact rock is determined using the fitting procedure proposed by Hoek and Brown (1997) based on the data requirements outlined by Hoek (1983). Studies (e.g., Bewick and Kaiser 2014; Kaiser and Kim 2014) have shown that independently determined UCS and sci values for the same rock type are not equivalent. Thus, UCS data cannot be used as a replacement for sci."

Jan 1, 2015

By L. J. Cabri

A gold sample assaying 11.4 g Ault was selected for this study. Approximately 99% of the gold in this sample occurs as discrete gold minerals; the balance occurring as invisible gold in pyrite (determined by SIMS analysis). The sample was coarsely ground and sieved, yielding -38, 17, 22 and 22 wt.% in the -400+160 um, -160+80 um, -80+40 µm and -40 µm size fractions. Assays of the size fractions gave a gold distribution of -32, 20, 21, and 27% respectively. Processing with the hydroseparator (model HS-02) gave two tailings products and one concentrate from each size fraction. Assays of the concentrate from each size fraction gave gold recoveries of -7, 7, 24, 19%, respectively. Polished sections were prepared from each hydroseparation product and studied by image analysis to automatically search for gold minerals. Calculations were done using the surface area of the grains of gold minerals found on the polished sections.

Jan 1, 2005

By R. A. Price

The base of the biozone of Olenellus is accepted as the most universally applicable criterion for defining the base of the Cambrian System. The use of this definitive criterion is restricted by important practical considerations. In the southeastern Canadian Cordillera this zone appears to truncate the basal ortho-quartzite of a west to east marine -transgression. This transgression began in Interior British Columbia in the Late Proterozoic and terminated in the region of the present Rockies in the Late Waucobian. Most of the material deposited by the transgressing sea originated in the eastern positive element &apos;Laurentia&apos; and was transported over the intervening low Proterozoic-Windermere erosion surface. The configuration of the advancing shoreline and the distribution of the sediments were controlled by the tectonic activity of positive elements in northwestern Montana (Montania) and in the Fairmont Hot Springs-Radium area of British Columbia.

Jan 1, 1956

By R. L. Every, A. G. Fonseca

"Sulphur deposition on the internal wall of a pipeline is caused by the temperature effect on the solubility of sulphur in the carrier fluid and is not due to particulate sulphur present. Deposition can be completely eliminated by proper insulation of the pipeline to prevent ""cold-spots"" and the resultant temperature gradient necessary for sulphur to precipitate from solution. Friction head losses for sulphur-condensate slurry systems are quite acceptable from a technical and economic standpoint and, in fact, are less than many present commercial slurry systems. Slurry transportation of sulphur in a hydrocarbon pipeline is a viable possibility and promises to have economic advantage over currently accepted transportation modes."

Jan 1, 1972

By R. F. Coulter

THE Flin Flon concentrating and metallurgical plants (Figure 1) of the Hudson Bay Mining and Smelting Co., Limited, lie adjacent to the town of Flin Flon, on the Manitoba-Saskatchewan border, 400 miles northwest of Winnipeg. Since the start of milling operations in 1930, over 50 million tons of ore from the Flin Flon mine have been treated in the concentrator. During the past few years, newly discovered orebodies have been brought into production and their ores processed at the company's main metallurgical plants. All these properties are within a 75-mile radius of Flin Flon and have aided substantially in augmenting plant metal production as well as retarding depletion of ore reserves in the Flin Flon mine. •Current satellite producers are the Schist Lake, Coronation, and Chisel Lake mines. The Schist Lake mine, located 3 ½ miles southeast of the main plant, is a copper-zinc producer. It was brought into production in 1954. The

Jan 1, 1962

By D. B. Dreisinger, M. R. Tavakoli

"Vanadium has been produced from a variety of sources. This metal is known to make aqueous solutions of complex speciation as a function of vanadium concentration and pH. Considering the method of leaching, the impurities in the pregnant leach solution, and the planned vanadium product, different extractants and flowsheets can be applied for solution purification. This paper reviews the purification of vanadium leaching solution using organophosphorus, solvating, and amine extractants. This review focuses on vanadium separation from iron, molybdenum, and uranium, which are often present in vanadium resources such as primary ores, fly ashes, and spent catalysts.RÉSUMÉ Le vanadium est produit à partir de diverses sources. Ce métal est connu pour permettre des solutions aqueuses de spéciations complexes en fonction de la concentration du vanadium et du pH. En tenant compte de la méthode de lixiviation, des impuretés dans la solution mère de lixiviation et du produit de vanadium planifié, divers agents d’extraction et schémas de traitement peuvent être mis en oeuvre pour purifier la solution. Le présent article étudie la purification de la solution de lixiviation du vanadium au moyen d’extractants organophosphorés, solvants et aminés. L’étude cible la séparation du vanadium du fer, du molybdène et de l’uranium, lesquels sont souvent présents dans les ressources de vanadium telles que les minerais primaires, les cendres volantes et les catalyseurs usés."

Jan 1, 2016

By John B. Hodgeson

AMMONIA is an essential constituent in the production of the ammonium-sulphate and ammonium-phosohate soil fertilizers manufactured by the Consolidated Mining and Smelting Company of Canada, Limited. The fertilizer plant, built in 1930 at Warfield, near Trail, provides a means of utilizing the large amount of sulphuric acid produced from the sulphur dioxide which is removed from the smelter smoke. The plant has an avail-able source of cheap power which makes the production of fertilizer economically possible. The fundamental operations involved in the production of ammonia at the Warfield plant are, first, the manufacture of hydrogen by the electrolytic dissociation of water; next, the recovery of nitrogen by the fractional distillation of liquid air; and finally, the combination of hydrogen and nitrogen in proper proportions and under suitable conditions to form ammonia.

Jan 1, 1938

By G. M. Ross, I. M. Ross, J. A. Scott

"The otherwise waste heat in many water streams in the mining industry can be used to provide space heating of adjacent infrastructure including laboratories, workshops, and offices. This can be achieved by using heat pump systems, which can work as a replacement or in conjunction with existing space heating. In the example investigated—process cooling streams at an ore smelter—the analysis provided illustrates that annual heating costs can be 19% lower and a simultaneous 62% reduction in CO2 emissions can be achieved.RÉSUMÉ Dans l’industrie minière, la chaleur qui serait normalement perdue des circuits d’eau pourrait servir à chauffer des structures adjacentes incluant les laboratoires, les ateliers et les bureaux. Cela pourrait se faire en utilisant des systèmes de thermopompes, qui pourraient remplacer ou s’ajouter au chauffage existant. Dans l’exemple étudié, des circuits de refroidissement de procédé à une fonderie, l’analyse fournie illustre qu’il est possible de réduire les coûts annuels de chauffage de 19 % et d’obtenir une réduction simultanée de 62 % des émissions de CO2."

Jan 1, 2016

By R. Amata

"The Gakara Rare Earth deposit in Burundi (East Africa) is unique for its high grade (e.g., 54.3% TREO on average) and low uranium and thorium levels. The majority of the light rare earth (RE) elements in material from Gakara are contained within the familiar RE minerals bastnaesite and monazite. Extensive metallurgical test work was conducted by SGS Minerals Services on mineral samples collected from the Gakara deposit. Various whole ore hydrometallurgical processing routes were examined in a scoping level test program. Preliminary beneficiation testing was also conducted, though it was determined that only marginal upgrading would be achieved with significant RE losses. Thus a hydrometallurgical process on whole ore was developed to minimize the overall process complexity and achieve maximum RE recovery. Results from the test work will be presented, along with the selected base case flowsheet involving agitated atmospheric sulphation of the RE minerals, RE double sulphate precipitation, caustic conversion, redissolution, and carbonate precipitation. Following the base case flowsheet, a purified cerium free mixed RE carbonate with low levels of radioactive elements was produced.INTRODUCTIONRainbow Rare Earths Limited (Rainbow) is a mining company engaged in the exploration and development of the Gakara rare earth deposit in Burundi; Figure 1 shows the project location. The project is located in the Bujumbura Province and 45 km from the Burundi capital of Bujumbura. Notable for its exceedingly high in-situ grade – 54.3% on average total rare earth oxide (TREO), low uranium and thorium levels and familiar rare earth minerals, bastnaesite and monazite – Gakara is the world’s richest rare earth deposit. The project, a previously operating mine from 1948–1978, has a significant mineral inventory base, a long life of mine, well understood mineralogy, and robust economics. Rainbow is focused on bringing Gakara into production in the near term, ramping up to produce 5,000 t/y of a 54%+ TREO concentrate."

Jan 1, 2016

By S. R. McCutcheon, D. R. Lentz, W. S. Downey

"Abstract - The Little Falls member of the Nepisiguit Falls Formation is situated in the northern part of the Brunswick Belt of the Bathurst Mining Camp and has been interpreted as the distal equivalent of proximal tuffaceous rocks that host the stratiform Brunswick No. 12 and No. 6 Pb-Zn massive sulfide deposits. It comprises fine-grained, greenish-gray tuffaceous sandstone in the lower part, and coarse-grained, crystal-rich tuffaceous sandstone in the upper part. Petrographic evidence suggests that these rocks have a turbiditic origin. The Little Falls member is underlain by the Vallée Lourdes member, mainly composed of relatively shallow-water calcareous rocks, and is conformably overlain by Mn-rich sedimentary rocks, mainly red argillites that host the Tetagouche Falls Mn-(Fe) deposit. All these rocks are considered to belong to the Nepisiguit Falls Formation, part of the Ordovician Tetagouche Group. Whole-rock geochemical data from the fine-grained tuffaceous sandstone and coarse-grained tuffaceous sandstone indicate that the two units of the Little Falls member are distinct. Zr and TiO2 contents, and total rare earth element (REE) values are higher in the coarse-grained unit (average Zr/TiO2 = 0.040, average SREE = 247 ppm, n = 6) than in the fine-grained unit (average Zr/TiO2 = 0.048, average SREE = 158 ppm, n = 17), which can be attributed to the variation in crystal content between the two units. Both units are HREE-enriched and have elevated La/Yb relative to the typical Nepisiguit Falls Formation. Overall, the geochemical data combined with evidence from the bounding units suggest that the Little Falls member was deposited in relatively shallow water, possibly in a near-arc environment. The relationship of volcanic facies within the Nepisiguit Falls Formation and the geochemistry of these facies indicate strongly that fine grained, reworked tuffaceous rocks, regardless of whether they are the distal equivalents of proximal tuffaceous rocks, are not associated with the major ore-bearing horizons of the Bathurst Mining Camp. Sommaire - Le Membre de Little Falls de la Formation de Nepisiguit Falls se retrouve dans la partie nord de la Ceinture Brunswick du Camp Minier de Bathurst ou elle a été interprétée comme l’équivalent distal des roches tuffacées proximales hôtes des gisements de sulfures massifs de Pb-Zn stratiformes Brunswick No.12 et No.6. Il consiste en grès tuffacé à grains fins gris verdâtre dans sa partie inférieure et en grès tuffacé à grains grossiers riche en cristaux dans sa partie supérieure. Les données pétrographiques suggèrent que ces roches ont été déposées par des courants de turbidité. Le Membre de Little Falls repose sur le Membre de Vallée Lourdes, lequel consiste principalement en roches calcareuses déposées en eau relativement peu profonde; il est de plus recouvert en concordance par des roches sédimentaires manganifères, lesquelles consistent principalement en argilites rouges hôtes du gisement de Mn-(Fe) de Tetagouche Falls. Toutes ces roches appartiennent à la Formation de Nepisiguit Falls, laquelle fait partie du Groupe de Tetagouche, d’âge Ordovicien. Les données lithogéochimiques des grès tuffacés à grains fins et à grains grossiers indiquent que ces deux unités du Membre de Little Falls sont distinctes. Les teneurs en Zr et en TiO2, ainsi que la teneur totale en Éléments des Terres Rares (ÉTR) sont plus élevées dans l’unité à grains grossiers (Zr/TiO2 moyen = 0.040, SREE moyen = 247 ppm, n = 6) que dans l’unité à grains fins (Zr/TiO2 moyen = 0.048, SREE moyen = 158 ppm, n = 17), ce qui pourrait s’expliquer par la variation de la quantité de cristaux dans chacune de ces deux unités. Chacune de ces deux unités présente un enrichissement en ÉTRL ainsi qu’un rapport La/Yb relativement plus grand que ce qui est typiquement observé dans la Formation de Nepisiguit Falls. Les données géochimiques considérées conjointement à l’information provenant des unités adjacentes suggèrent que le Me"

Jan 1, 2006

By E. Fritz

This paper reviews the history, developments and 10 milestones of the oxygen steelmaking processes, with a special focus on conventional autothermic converters, high-speed converters with a blowing rate up to 5 m3n/t min and allothermic converters with coal addition, post combustion and the possibility to increase the scrap rate up to 50%. Related operating results are introduced. A new process route, which is based on hot metal and chromium ore, is outlined. The cost advantage for the production of 304 stainless steel grade is higher than 100 USS/t. The synthesis of EAF and oxygen converter steelmaking, a comparison of decarburization rates, refining combustion burners for optimized oxygen-management in EAF and an example for a large advanced EAF are outlined. Possibilities of flexible steelmaking and the growth and outlook of worldwide oxygen steelmaking are described.

Jan 1, 2004

By V. Gregoire

THE DEVELOPMENT by the Iron Ore Company of Canada of the Quebec-Labrador mining project, which eventually led to &apos;Iron Ore in 1954&apos;, involved, from the start, several distinct undertakings. Among them, the most important were: The construction of a 360-mile railway, linking Knob Lake with Seven Islands. The erection of a railway terminal, and harbour facilities, at Seven Islands itself. The building of an entire townsite at Schefferville (formerly Knob Lake) The construction of two hydroelectric plants; and, finally, The development of a sufficient number of orebodies to enable a production of 10 to 15 million tons of ore a year. Since these phases of the project have already been the subject of previous discussions, this paper will not elaborate further on them but will rather concern itself with a brief outline of the Company&apos;s current mining practices.

Jan 1, 1958

By H. J. McQueen

The modeling of the extrusion of 6061 alloy and its composites with 10 to 20 vol% Al203 or SiC by two techniques. The uniaxial finite element method FEM (DEFORM" ) provided force-stroke curves and temperature rise over the range 450-500 °C, 2.6-5mm/s and extrusion ratios of 31 and 64. The traditional technique considers ideal work and redundant work as well as friction and uses average temperatures and strain rates. The two techniques are used to clarify each other and to extend the analysis to 400 and 350 °C. The calculated efficiencies are compared to measured values in extrusion trials and to values derived for 7075 extrusion analyses. The analyses are based on constitutive equations determined by torsion testing tests.

Jan 1, 2004