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By John Gittins

Lots 11 and 12, Range IX, Calumet island, are underlain by a Grenville metamorphic complex into which sills of tourmaline granite pegmatite have been injected. The pegmatite has an average mode-potash feldspar 65 per cent, sodic plagicdase 10 to 20 per cent, quartz 5 to 20 per cent, tourmaline 10 to 15 per cent, accessory minerals < 5 per cent; it is unzoned except for a narrow border zone. Some of the feldspar has been replaced by calcite. Microcline has been ?partially replaced by sodic plagioclase. Three varieties of tourmaline are present (black, blue, and green) and spectrographic analysis suggests progressive compositional changes during its crystallization. The presence of U- and Th-bearing minerals in the pegmatite prompted the Quebec Nickel Cor,porat10n, Ltd., to explore the possibility of developing the pegmatite but it does not appear that this is economically possible at the ? present time. Tt\e Grenville metamorphic complex consists of recrystallized limestones and calcsilicate rocks of the albite-epidoteamphibolite facies and the amphibolite facies, which were derived from sedimentary rocks. Several of these are dis-equilibrium assemblages, and retrograde metamorphism has probably formed biotite and epidote from hornblende. The schistosity of the gneisses dips steeply eastward. Numerous strike faults are roughly parallel to the schistosity and one of the pegmatite sills is bounded by such a fault, dipping at 60 ° with about one foot of fault breccia. The general structure of the map-area seems to be an asymmetrical syncline ?overturned to the west. The emplacement of the pegmatite is associated with a period of folding, metamorphism, and igneous intrusion.

Jan 1, 1956

By M. H. Loveman

THE orebody described below has been rediscovered and developed within the last 3 years. It has, however, been known and worked by the Chinese for hundreds of years. When assay values and size are considered, it contains what is probably one of the largest single bodies of zinc and lead sulphides yet found. The tonnages developed at other places, as at Broken Hill, are much greater but the average zinc and lead sulphide contents are considerably lower than at Bawdwin. Bawdwin is situated in the semi-independent State of Tawng Peng, one of the numerous units which make up the Northern Shan States. These States are under British rule and are generally considered as a portion of Burma. They are governed as a separate administrative unit, however, under the Lieutenant Governor of Burma. Each State is under its own chief, or Sawbwa, who has considerable power over his own subjects. Bawdwin is approximately in latitude N 23°6&apos;, longitude E 97°20&apos;, about 50 miles south of the nearest point on the Chinese border and 450 miles north of Rangoon (Fig. 1). The period at which mining was first begun at Bawdwin is unknown. The most reliable records have been obtained by deciphering local Chinese inscriptions and from these it is concluded that the work dates back to at least the beginning of the 15th century. The first undoubted reference to the mines by a European is by Symes in 1795. Crawford in 1827 estimated the output of silver from the mines at $600,000 annually. At about the middle of the 19th century the rebellion of the Chinese Mohammedans in the neighboring Chinese province of Yunnan so weakened the power of the Chinese that the incursions of hostile tribes (Kachins) made work extremely dangerous. The mines were finally abandoned by the Chinese about 1868. The closing down of the mines was probably not entirely due to outside causes but may have been influenced somewhat by the increasing difficulty of handling the water, as the workings gradually descended below the water level of the district. Several attempts were made by the Burmese kings, Mindon Min and Thebaw, to resume operations, but because of a

Jan 12, 1916

By L. J. Drew

The plate tectonic setting, regional geology, and certain aspects of the economic geology of the iron-rare-earth-nio-bium ore bodies at Bayan Obo, Inner Mongolia, China, were studied by a team of geologists from the Tianjin Geologic Research Academy and the U.s. Geological Survey between 1987 and 1989. These ore bodies were formed by hydrothermal replacement of Middle Proterozoic dolomite in an intracontinental rift setting. A variety of veins and/or dikes that have a carbonatite-like mineralogy cut the footwall clastic rocks and migmatites. A stockwork of veins occurs at several locations in the footwall. The hanging wall is a shale that has been converted to a K-metasomatite and has microcrystalline potassium feldspar as its principal constituent. This shale served as a sealing caprock that contained the chemical solutions that reacted with the dolomite and that created the enormous concentration of mineralized rock in an 18-kilometer-long syncline. The rocks that host these ore bodies and the associated mineralized areas occur today as roof pendants in granitoid rocks of Pennian age that were emplaced during a continent-to-continent collision during that period.

Jan 1, 1991

By A. K. Snelgrove

Introduction ?Concerning the inland commodities, as wel to be drawen from this land (Newfoundland) there is nothing which our East and Northe.rly countries of Europe doe yeelde, but the like also may be made in (ît) as plentifully by time and industry : Namely, rosen, pitch . . . metalls, and many moe. All which the countries will aford, and the soyle is apt to yeelde ... For besides these alreadie recounted and infinite moe, the mountains generally make shew of minerall substance : Iron very common, lead, and somewhere copper. I will not auerre of richer metalls: albeit ... more then hope may be concieued thereof. " - Narrative of Captain Hayes, second-in-command to Sir Humphrey Gilbert&apos;s Expedition, IJ83 (From Hakluyt). The investigations set forth in the following pages were made in the field in Newfoundland during the summer of 1927, and later in the laboratories and library of McGill University, and in the library of the Canadian Geological Survey at Ottawa, with the purpose of collating and adding to our knowledge of the geology of an area roughly wedge-shaped in outline, and nearly nine thousand square miles in extent, stretching across the centre of the island of Newfoundland, from the southwest to the northeast coasts. To the description of this district, which contains most of the known mineral occurrences of Newfoundland, the term mineral belt is here introduced.

Jan 1, 1928

By R. C. Schmidt

The Mont Klahoyo magnetite deposit is located about 600 km northwest of Abidjan, Ivory Coast. During an exploration period ending in 1977 an international joint venture group investigated the deposit and proved reserves of 670 million tons grading 36% iron. The deposit, occurring at the northeast end of the Baoubly-Kiriao chain of Precambrian iron formations, is associated with amphibolites, pyroxenites and gneisses of the Liberian Shield. At Mont Klahoyo occur two separate iron formations of which the lower member is the ore body. This lower member consists of a highly metamorphosed - banded quartz-magnetite iron formation in which iron silicate bands alternate with beds of quartz-magnetite. mphibolite-pyroxenites and sillimanite-cordierite-garnet gneisses form hanging and footwall rocks. The iron formation has been folded into an elongated overturned "Z" shaped major drag fold with axes trending and plunging approximately northeast. Beds are vertical or dip steeply to the southeast. The ore zone has an average thickness of 130 m and outcrops intermittently over a distance of approximately 5.5 km. Based upon detailed studies of drill cores and the results of ore dressing test work, eight stratigraphic units, identified as K-1 to K-8, are recognizable in the iron formation. Four interbedded units are low grade silicate zones (silicate facies) with the remaining quartz-magnetite units (oxide facies) repre¬senting the important ore zones of the Mont Klahoyo deposit. The ore-bearing "K" units are subdivided further, based upon their specific lithologies, iron content and concentration characteristics, into eleven ore types. The identification of these ore types is considered particularly important to mine planning and flowsheet design. A cap of oxidized materials overlies the primary quartz-magnetite iron formation but no enrichment has occurred. It is proposed that the Mont Kalhoyo iron formations were deposited, possibly chemically, in a volcanic environment as a siliceous iron formation with volcanism providing the primary source of iron and silica. Metamorphism converted the siliceous iron formation to a relatively coarse-grained quartz-magnetite-silicate iron formation.

Jan 1, 1979

By Thomas H. Heine

"The Rabbit Lake uranium deposit is located at 58° 11’00”N.. 103°42'36""W., close to the west side of Wollaston Lake, and approximately 800 km north of Saskatoon. The orebody is hosted by Aphebian Wollaston Group rocks, initially deposited as a series of shallow-water marine sediments consisting, in part, of carbonates and possible saliferous petites. Metamorphism during the Hudsonian Orogeny, peaking at about 1850 Ma, recrystallized the sediments to upper amphibolite grade paragneisses. This was accompanied by partial anatexis. The waning stages of Hudsonian orogenesis appear to be marked by minor granitic intrusive activity.The post-Hudsonian period was marked by a long interval of physical and chemical erosion, resulting in the unroofing of the Wollaston metamorphic complex. The entire region underwent extensive lateritic weathering under tropical to subtropical conditions. Carbonates were especially vulnerable and, in the Rabbit Lake area, suffered extensive solutioning with accompanying formation of collapse breccias. Old zones of weakness also underwent periodic reactivation.It was during this period that uranium was leached from the surrounding meta-sediments by oxidizing meteoric waters, and transported into the karsted and fractured rocks of the Rabbit Lake doline.Athabasca Group sediments eventually covered the deposit, their diagenesis taking place at about 200 °C and 900 bars. This allowed the partial to complete recrystallization of the initial mineralization, resulting in a minimum age of 1281 ± 11 Major ""first""-generation pitchblende. Periodic fault/fracture reactivation modified the hydrologic regime within the deposit, resulting in episodic mobilization and recrystallization of pitchblende and other uraniferous species. This is clearly shown in the open pit at the present time: uranium is being mobilized and recrystallized on damp pit walls as bayleyite and liebigite due to the modification of the hydrologic system by mining activities.The uranium mineralization occurs mainly as fracture fillings, coatings, and impregnations within breccia zones and intensely altered metasediments. Lesser mineralization is intimately associated with phyllosilicates which form the matrix of a carbonate-col/apse mega-breccia. The primary ore mineral is pitchblende, consisting of five generations, and from which a large suite of secondary uraniferous minerals have formed. On a gross scale the metal content of this deposit appears to be simple, consisting almost exclusively of U, but minor Ni, As, Cu, Se, Fe and Co are also present. The eastern limit of the mineralization is defined by a vertically-dipping microgranite dyke - breccia complex, containing high-grade uranium values. The orebody is truncated to the west and at depth by the Rabbit Lake reverse fault. Minor mineralization occurs as fracture fillings in unaltered plagioclasite in the footwall of the ore body. Precipitation of uranium from solution could have taken place by a number of processes. A mobile reductant (methane, carbon dioxide, etc.) may have been generated from graphite present in some of the host rocks of the orebody. Sulphides are also a common accessory and may have aided in the formation of a reducing environment. Phyllosilicates may have acted as adsorbants for uranium, allowing for its fixation. This metal has also been incorporated into the phyllosilicates themselves."

Jan 1, 1986

By Rodgers Peale

The Waite mine, as it is locally termed, is situated in the Rouyn district, in the townships of Duprat and Dufresnoy, Quebec, and lies about 340 miles north of Toronto. Due to the impetus given prospecting in the Rouyn district by the discovery, some years ago, of copper-gold ore on the Horne claims, many exploration parties were put into the field. Early in 1925, J. H. C. Waite, C. H. Ackerman, and T. Montgomery staked the claims which now comprise the mine beating their names. Trenching and diamond drilling soon disclosed an ore-body of commercial size and grade, and by the end of 1928 a shaft had been sunk 300 feet and the mine was producing 150 tons of direct-smelting copper ore a day. In the summer of 1925, Dr. H. C. Cooke, of the Geological Survey, made a reconnaissance survey of the property (1), and since that time work of the same nature has been done by several others. MacGregor has published some interesting data on the Amulet mine (2). Using as a background a summer&apos;s work on the Horne claims at Noranda, the writer spent the summer of 1929 at the Waite.

Jan 1, 1931

By A. A. Steel

(Spokane Meeting, September, 1909.) DURING. the summer of 1905 I was employed by the U. S. Geological Survey to investigate the geology, Mining, and preparation of barite in most. of the fields of the United States. The Eastern districts have been more or less completely described ; the Virginia field in detail by Thomas L. Watson, in his paper, Geology of the Virginia Barite-Deposits,&apos; and other fields in abstract., including statistics of production and references to current literature, by various authors .2 There have also been published a few details of the occurrence of barite in the lead-mines of Washington county, Mo.3 The other accounts of this district are erroneous and meager, and since this field is the most important one in the United States at the present time, a detailed description of the local geology seems doubly desirable. Barite-deposits are scattered over nearly the whole of Washington and adjoining counties, but. the product, is all mined from the areas indicated upon the sketch-map, Fig. 1, and is shipped from the stations of the St. Louis, Iron Mountain &. Southern railway, between Blackwell and Potosi, from 45 to 60 miles SW. of St.. Louis. The topography is for the most part gently rolling, with slightly graded streams, usually less than 200 ft. below the higher hill-tops. Along Mineral fork and Indian creek are :some steep bluffs and cliffs, affording good exposures of the

Feb 1, 1910

By J Vann

Geometallurgy is inherently multidisciplinary and it gains its power to deliver improved outcomes for the minerals industry by bridging silos between disciplines. This cross-disciplinary approach unlocks value, identifies (and avoids) value destruction and provides a pathway to better implementation of an energy efficient and sustainable minerals industry. Despite this promise, we argue that the cross disciplinary approach also represents the greatest threat to the success of geometallurgy. Some key cross disciplinary issues identified are:Geometallurgy has so far evolved in the technical sphere, mainly by collaborations of geologists and metallurgists. Consequently, in many cases the business dimensions and value have not been incorporated. Financial and risk evaluation viewpoints need to be assimilated into the geometallurgical paradigm. In fact, until such measures are integrated into practices, the value cannot be fully demonstrated.The historical and current efforts on geometallurgy have been highly focused on improved sampling and measurement of geometallurgical properties or appropriate proxies. This work has been driven by professional and academic geologists and metallurgical engineers. It is notable that mining engineers (who are critical in the value delivery of geometallurgy through changed planning approaches) have so far been at the margins, or absent. The construction of valid three dimensional (3D) geometallurgical models raises some important organisational, mathematical and geostatistical considerations. The enhancement of resource models to account for geometallurgical aspects must be managed carefully if the full value of geometallurgical thinking is to be realised.The use of 3D geometallurgical models to change business decision making and practices is the real nub of the problem. We believe sophisticated scenario based evaluation methods are required if the potential impacts of spatial rock properties on processes further down the mining value chain are to be realistically evaluated. Such changed practices require ‘whole of value chain thinking’ to embed this change into the business in an ongoing way.Because profitable geometallurgy demands changed approaches to business decision-making and also organisation of the firm (radically changed in some cases), the senior executive viewpoint must be incorporated into the language and thinking of geometallurgy. This is unavoidable if the establishment of a geometallurgical approach to project evaluation, development and operation is to be successful and sustained.A powerful analogy for the problem faced by geometallurgy is the transformation of safety culture in the mining industry in the past 20 years. We argue that, as in the safety revolution, explicit models, cultural change and management of the ‘soft’ dimensions of the problem are pivotal to success of geometallurgy. In light of this, we propose a model (‘the Geomet Curve’) that gives a framework and pathway for geometallurgy in seven steps. The implications of this model for technical and organisational steps required at different stages are discussed.

Sep 5, 2011

By L W. Morley

The Division is concerned with physical methods as applied to geo-logical research and mapping. An at-tempt is made to describe long-term goals, illustrated by examples of projects in the fields of aeromagnetic interpretation, palaeomagnetic re-search, Pleistocene and groundwater geophysics, seismic surveying, electromagnetic research and instrument development. Cooperative projects in surveys and research, with universities, private companies and provincial organizations, are frequently undertaken. An outstanding example of this is the recently approved Federal-Provincial Aeromagnetic Survey Plan, the purpose of which is discussed both from an economic and a scientific point of view. HISTORY OF THE DIVISION M AGNETIC, electrical, seismic and gravity methods, as a means of extending the geologist&apos;s sphere of observation beyond the head of his hammer, came into wide-spread use for the first time after World ?war I. Interest in these methods was aroused amongst geologists of the Geological Survey and, in 1928, a group of these geologists and university

Jan 1, 1963

By Frederick B. Henderson

On 10 August 1976, The Geosat Committee was organized in Denver to institute The Geosat Program. This program is an industry backed effort to evaluate and help select optimum space remote sensing systems for geological purposes. It is believed that the recommendations of The Geosat Committee can be supported by industry as additional exploration tools which can materially benefit industry and the Nation with respect to our energy and other natural resources needs. Appended is a general summary of The Geosat Committee Organizational Meeting and general review of The Geosat Program. The Geosat Workshop Report. The Geosat Committee, and The Geosat Program will be reviewed at a special afternoon session, Friday, 3 September.

Jan 1, 1976

By G. Drennan, A. Cameron

"South African mining operations depend on the skilled professionals produced through the tertiary education sector. In geoscience courses at the University of the Witwatersrand, which lead into the mining sector, there has been a significant increase in student intake over the past 15 years. This increase has been characterized by a radical shift in demography: in classes where white male students once formed the majority, black female students are now in the majority. This demographic shift appears closely linked to policies addressing issues of social justice and transformation in post-apartheid South Africa. We document this change and consider the role played by employment equity legislation (as in the Mining Charter) and corporate social investment strategies in the mining industry, notably through bursaries offered to black female students. We also look at the changing needs of the industry, where the critical need for managerial skills, not just technical knowledge, is highlighted through data from surveys of past students and industry managers. Our findings indicate the need for a curriculum adjustment to meet these changing requirements, as well as more rigorous selection criteria for bursars than simply gender, race, and appropriate matric results. IntroductionThe South African economy has historically been linked to mining and the exploitation of mineral resources. South African mining operations are dependent on the professional labour that is produced through the tertiary education sector, with critical thinking, teamwork, and the art of negotiation having been identified as the crucial skills required for this industry (Sideropoulos, 2014). Over the past three decades the South African system of education has gone through a period of dysfunction that it is struggling to rectify (Maphai, 2014). This has impacted on the levels of academic preparedness of students applying for places in higher education. Concurrently, government and university policies have widened access to higher education in response to the need to address issues of social injustice and transformation related to South Africa’s history of apartheid. As a result, the number of students admitted to universities has increased dramatically. In the School of Geosciences at the University of the Witwatersrand (Wits), the increase in student numbers has been accompanied by a significant change in demographics: classrooms which in the past were dominated by white males have given way to classrooms in which black females are often in the majority. This demographic shift is related to legislation such as the Mineral and Petroleum Resources Development Act and the Broadbased Socio-Economic Empowerment Charter, developed to reshape the socio-economic and equity frameworks of the country (Botha and Cronje, 2015). Requirements aimed at transformation in terms of management, skills development, and employment equity, together with corporate social investment (CSI) requirements, have resulted in bursaries being made available to attract students from designated groups, which in turn has increased the number of black students, and notably black female students, taking courses in geosciences. However, due to the economic downturn, instability in the mining industry has recently resulted in the downsizing of some mines, with international investors pulling out of South Africa. This instability resulted in devastating strikes across all sectors of the mining industry (Stewart, 2013) and in Marikana, an important platinum mining area, the strike culminated in a deadly shoot-out between miners and police. The resulting tensions spilled over into the gold mining sector, resulting in further strike action, shaft closures, and retrenchments. These challenges have implications not only for the mining industry in South Africa, but for the tertiary education providers whose graduates would have been absorbed into the mine-related workforce."

Jan 1, 2017

By Gary S. Brierley, Tracy J. Lyman

INTRODUCTION Geotechnical engineers play a major role in tunnel design primarily because tunnels are constructed entirely within the ground. In general, this role can be divided into two major tasks: subsurface investigations and project design. Under subsurface investigations, it is necessary for the geotechnical engineer to accurately describe the ground in which the project will be built. Under project design, it is necessary for the geotechnical engineer to work together with other members of the design team to make certain that the tunnel fulfills its intended purpose at least cost. Given in the paper are the authors&apos; opinions about what constitutes an adequate scope of services for these two tasks on a tunneling project. SUBSURFACE INVESTIGATIONS o Background Study All subsurface exploration programs for tunnels begin with a thorough investigation of background information about the proposed site. Such background information includes geologic, reports topographic maps, aerial photography, and case history reports of other nearby tunnels. Once completed, it is necessary to study the background information so that the proper scope and magnitude of subsurface exploration work is performed in a manner that provides maximum input to a knowledge of those intact and rock mass properties that are important for an understanding of the entire ground mass. The blind application of field and laboratory techniques, no matter how sophisticated, is wasteful and potentially

Jan 1, 1989

Disposal of solid and liquid wastes from mining and milling operations has become a focus of attention in recent years. Consequently, the geotechnical engineer is more frequently associated with design of disposal facilities. Jack Wulff, a representative of one consulting firm with experience in this field, talks with ME about the geotechnical engineer&apos;s contribution. Mr. Wulff, mine and mill waste disposal today is receiving more attention-and many more dollars-than in the past. Regulatory agencies have promulgated demanding requirements concerning mill waste (especially uranium mill waste) and specialist consultants are frequently being called in to design disposal systems. What can the experienced geotechnical engineer add to the development of waste disposal facilities? It&apos;s true that geotechnical engineers have recently become more visible in the minerals sector, but we&apos;ve been around mining for a long time-as foundation engineers for mills and mine support buildings, and for geotechnical aspects of open pits, pipelines, railroads, roads, and so forth. We&apos;ve also designed water supply dams, which could be considered recursors of tailings dams and other forms of disposal systems. Let me show by example what geotechnical engineering can contribute to waste disposal facility design. I recently was asked to look at several small wastewater impoundments which had failed. The design of the earth embankments appeared, at first glance, to be rather conservative. They were only about 3.4 m high, the slopes were 3 to 1 (horizontal to vertical), with about 24 m of bottom contact with the earth foundation. But there had been three episodes of dike failure in a few months, all upon initial filling. The problem was the nature of some material in the foundation that was also used as structural fill-a dispersive clay that readily deflocculated and eroded on contact with water, especially with seeping or flowing water. The design did not include the defensive measures required to use such materials confidently in water retention structures. Apparently, the designer did not recognize the potential problem posed by the unusual soil characteristics. That&apos;s the sort of engineering information fundamental to geotechnical engineering, but not necessarily a part of the civil, structural, or mining engineer&apos;s professional training or experience. This difference in expertise is not simply a matter of factual knowledge-it also affects the design process. The structural engineer can design a structure to fit the client&apos;s functional needs and can specify the materials (grade of steel, PVC, concrete, etc.) to meet the demands of the design. The geotechnical engineer&apos;s design process is somewhat different, since we work with natural materials, not man-made materials produced according to specification. We first have to establish what kinds of materials are available (usually directly from the chosen site, since importation of materials becomes expensive). Then we determine the engineering properties and characteristics and, finally, design the structure to fulfill the client&apos;s requirements within parameters dictated by available materials. In brief, the geotechnical engineer works with naturally-evolved, not man-made, materials and uses design techniques developed to accommodate that fact. Because no two sites are exactly alike in configuration, structural (geologic) characteristics, or available materials, there will be unique design and judgmental questions to be resolved on virtually every project. You said that water retention dams could be considered the precursors of tailings dams-you probably had a specific technical relationship in mind. There&apos;s a very strong carryover of methodology from earth dam design, where the technology developed and where it has become very refined. In designing a tailings impoundment or similar facility, essentially the same procedures of field sampling are involved (with a geotechnical engineer or an engineering geologist directing the program since representative

Jan 7, 1980

By I. Blayda

The purpose of this work is to study and make comparative analysis of germanium extraction and related valuable components of the sublimates from the burning of domestic power coals (product 1) and germanium sulfide materials, which are a waste of lead-zinc production (product 2), by traditional chemical methods (distillation of germanium in the form of tetrachloride from raw and preliminary burning source) and by microbial bioleaching of sulfur-oxidizing bacteria. The dependence of the germanium extraction by chemical methods from phase composition of the initial raw materials was installed. The germanium tetrachloride extraction from products 1 and 2 were 78.50 and 19.52%, respectively. Such difference in indexes on extraction, is caused by germanium confinement as concomitant trace component to the basic phases to carriers. The share of acid-non-soluble compounds (tetragonal modification GeO2 and silikogermanaties) in the product 1 account for 21.5 % of germanium. Ratio between acid-soluble and acid-not -soluble germanium forms are 19.52 and 80.48 %, respectively, in the product 2. Our experiments have shown, that implementation of restorative firing (with addition of 30-40 % carbon at 1150 0?) of sulfide product 2 considerably impacted on the extraction of germanium tetrachloride (91.76 %) in comparison with its low enough extraction at straight distillation of hydrochloric acid (19.52 %). The results are confirmed by a set of physical methods. The results of processing the same so-called hard phase?s material (product 2) with the help of microorganisms are presented. It Has been established, that selected strains of bacteria are capable of extracting from initial raw materials not only macro components (iron, zinc, lead, manganese, aluminum, nickel), but also micro impurity of rare metals (gallium, germanium, zirconium). It is important that these metals were not extracted by traditional chemical methods (with application of aggressive conditions and heats) independently of the phase composition of the source. Almost complete extractions of germanium in solution using sulfur-oxidizing bacteria take place in the first day of the process independently of the phase composition of the source and the type strain. The results have practical significance and can be the basis for developing a unified biotechnological method of technogenic waste processing with a purpose of their sterilization and detoxification with simultaneous obtaining concentrates of valuable metals. Keywords: germanium, extraction, sublimates, bioleaching, sulfur-oxidizing bacteria.

Sep 1, 2012

By R. J. Latino

Because of the lack of a universally accepted definition or standard for RCA, we are left to our own conventions in the marketplace as to what is most ?effective? or a ?Best Practice? for our own facilities or organization. This lack of uniformity in the application of RCA produces an equal lack of uniformity in the measureable outcomes of RCA on the bottom-line from site to site and industry to industry. What is the definition of success for an RCA? Is it regulatory compliance? Is it some quantifiable measure of bottom-line performance? Is compliance and bottom-line performance the same thing? Can we measure the ROI we receive by doing compliant RCA? These questions must be adequately addressed if any definition of RCA is to be effective on the bottom-line. Like our various Corporate Vision and Mission Statements, what would be our Vision and Mission for RCA? When pondering the answer to this question, we should consider: ? What Key Performance Indicators will the Success of RCA be Linked to? This provides a direct correlation to the corporate dashboard and therefore garners support for the RCA effort when implemented at the sharp end. Not until we know what KPI?s will effectively measure our maintenance and reliability objectives can we begin to establish which opportunities will afford the greatest returns1. ? What Bottom-Line Metrics will be Tracked to Measure the Effectiveness of Our RCA Effort? Will it be increased production, profitability, regulatory compliance, etc.? Will it be decreased injuries/fatalities, claims, customer complaints, risks, etc.? We should be specific about these metrics and their correlation to the metrics on our corporate dashboard. ? What Will Trigger an RCA Investigation? Normally companies will establish quantifiable thresholds to be surpassed before an RCA will be conducted. Examples may be an OSHA recordable injury, a failure event in which production losses exceed $250,000, an equipment failure in excess of $50,000 or a regulatory violation. This is the norm. However, we should realize this is using our RCA skills totally on a reactive basis. High Reliability Organizations (HRO) strive for proaction and they also use RCA proactively. Why can?t we use RCA to analyze why unacceptable risks from an FMEA are so high? It is perfectly applicable yet rarely implemented in this fashion.

Feb 27, 2013

By D. Atkinson

"Porphyry molybdenum-tungsten mineralization on the east flank of Hudson Bay Mountain crops out over 5 km2 and is intersected to depths of 2 km. Features such as a hornblende-biotite aureole, mineralogical zoning and dike, vein and fracture geometries within lithologies of the Middle to Lower Jurassic Hazelton Group and Cretaceous Skeena Group reflect an intrusive complex, the Upper Cretaceous to Early Tertiary Hudson Bay Mountain stock which has been intersected by drill holes. The stock is believed to be the mineralizing agent. A southeast-dipping granodiorite sill has been outlined by drilling within the Hazelton Group. Molybdenite and scheelite veins cut all rock types; however, the granodiorite sill hosts a higher density of fine-grained, banded, quartz-molybdenite and pegmatitic quartz-molybdenite veins reflecting a competency contrast between the intrusive sill and other country rock. Due to the relative abundance of these veins, grade is higher within areas of the sill. Above the 15000£ cross-cut 20.6 million tonnes grading 0.401% MoS2 and 0.041% W03 have been defined. During exploration of the deposit sampling procedures had to be adjusted because of the nugget effect attributed to drill intersections of banded and pegmatitic veins.IntroductionMolybdenite was discovered in outcrop at the foot of Kathlyn Glacier on Hudson Bay Mountain and first reported by the Geological Survey of Canada in 1944. The deposit has several names: Hudson Bay Mountain or Glacier Gulch, both after its location, and Yorke-Hardy after the original staker.The deposit is on the east flank of Hudson Bay Mountain, 9 km northwest of Smithers, west-central British Columbia, within NTS area 93L/14 (54° 49' North, 127° 18' West, Fig. 1). Hudson Bay Mountain, on the southern edge of the Bulkley Valley, is a dominant topographical feature reaching 2590 m elevation. Mineralization is partly overlain by the Kathyln Glacier which is visible from Highway 16. Access to the 3100 m of underground development is from a portal at 1066 m elevation on the east slope of Hudson Bay Mountain."

Jan 1, 1995

By C. J. Cajka

Commodity agreements, trade liberalization, producer cartels, the New International Economic Order, price stabilization and access to supply are buzz words of the day. The international concern and dialogue on these concepts, often by a new breed of politically motivated experts, have generated intense interest in seeking an international solution to natural resource problems. While this momentum was maintained during the past year, the growing incidence of protectionist actions by several major nations has been eroding confidence in the global approach. The seriousness of current difficulties has created an urgent need for decisive action. At the same time, the limitations of the global approach have become more evident.

Jan 1, 1978

By Aidan Giblett

"It is important to make a clear distinction on the scope of work of the Global Mining Standards and Guidelines (GMSG) guideline for sampling grinding circuits. Many mineral processing practitioners are familiar with the sampling and surveying of comminution circuits, in particular grinding circuits, for performance diagnosis and the identification of optimization potential. These surveys often provide information for population balance modelling of individual comminution and classification unit processes, and consequently require a large amount of information to calibrate and validate the unit models. As a result, these surveys are labour intensive, somewhat expensive, depending on internal capabilities of the mine site or company and have a long time span from initial planning to final reporting. They also require a high level of expertise to process the survey data, simulate the circuit and make sensible recommendations on follow up actions.As a result of these factors, full grinding circuit surveys are not a common occurrence at a large number of processing facilities, and several years may pass before follow up surveys are conducted. In the ensuing gap between surveys, the efficiency of the grinding circuit must often be taken on faith, and this is considered an unacceptable lapse in an environment of strained natural resources and low commodity prices.To support the rapid and productive energy efficiency analysis being promoted by the ICE working group, a much simplified survey and analysis process is required. The process reflected in the GMSG guideline is indeed more conducive to frequent analysis, at a skill level that is well within the capabilities of the average plant metallurgist. As a result, it becomes feasible to conduct mini-surveys of plant performance, which can be used to quickly and precisely diagnose the high level impact of process changes. These methods can also be manipulated by an experienced practitioner to provide sufficient information for modelling of the circuit to estimate the impact of process changes, allowing an initial rate and rank exercise to focus plant optimization efforts."

Jan 1, 2015

By F. J. Alcock

IN the summer of 1934, gold was discovered on Lodge bay, on the north shore of lake Athabaska in northern Saskatchewan, about fifty miles east of the Alberta boundary line. The first claims were taken up by the Consolidated Mining and Smelting Company of Canada, Limited, and there was a &apos;rush&apos; to locate similar showings. Staking continued through the summer and succeeding winter, and in the spring of 1935 the provincial government established a recording office at a convenient point which is central to the more important holdings and where &apos;planes can land in any weather. During the past summer, the name of this townsite was changed from Beaverlodge to Goldfields, and a post office was established here. The season was one of great activity; a great deal of assessment and development work was carried out and a large amount of further prospecting done. In addition to the work by private companies, geological investigation was carried out in the region by a Federal Geological Survey party under the charge of the writer and a reconnaissance examination was made of an area of some 7,000 square miles surrounding the region of particular interest. Though this was the first discovery of gold in the region it was not the first occasion that prospecting had been carried out along the north side of lake Athabaska. Over twenty years ago, a number of prospectors were at work in the area and a large number of claims were staked, many of which were never recorded. One man by the name of Piché, in the years 1910, 1912, and 1913, took up a considerable number of claims north of Pine Channel narrows, east of Fond du Lac. His discoveries, which consisted of small showings of sulphides in sedimentary gneiss, proved to be of no economic importance. In 1915, a sudden widespread interest was aroused by the report that a sample of ore collected near Fond du Lac had yielded a very high assay in silver. In March and April of that year, prospectors began to rush into the field by dog teams to take up claims, and, as soon as the Athabaska river was free of ice, others started by boat from Athabaska Landing. Some hundreds of claims were staked and recorded in the Dominion Land Office at Edmonton or at Fort Smith. By July, most of the prospectors had? left the region, having failed to find any silver ore. In 1921, considerable prominence was given to the area a few miles east of Goldfields by reports that very large masses of iron ore were available there. Claims were taken up, but the material is much too low grade to be considered commercial ore.

Jan 1, 1936