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By A. A. Paoli

The selection of a mining plant for carrying on development work presents many problems distinct in themselves, and affected by various local factors. In this paper, the writer proposes outlining and discussing in some detail the chief factors governing the economic selection of such plants. This will be followed by an enumeration of the underground and surface plant required for carrying on several hypothetical exploratory and mining operations. Where it is impossible or not convenient to obtain hydro-electric power, and where wood for fuel is scarce, we now find oil engines being used. A 100 h.p. oil engine, such as would be required to operate a three-drill air compressor, consumes approximately five Imperial gallons of fuel-oil per hour at full load. On the basis of a 60 per cent load factor, this gives, for eight hours' operation, a probable actual consumption of twenty-four Imperial gallons.

Jan 1, 1929

By Sydney C. Mifflen

COAL MINING, with its some 15,000 employees, is directly responsible for the livelihood of one-fifth of the population of the Province of Nova Scotia and indirectly so for that of possibly another fifth. Deposits of coal are known and worked in four counties of the Province, from which is being produced yearly tonnages as noted below: Cumberland County 750,000 tons Piccou County 400,000 tons Inverness County 100,000 tons Cape Breton County 5,250,000 tons TOTAL FOR NOVA SCOTIA 6,500,000 tons Production in Cape Breton county is entirely from the one source, the Sydney coalfield, and not only is this field the most important in respect to output, as is disclosed above, but it is also the largest presently known deposit in the Province and holds the greatest tonnage yet in reserve for future mining. In the light of the above more or less generally known facts, it is trite to remark on the importance of the Sydney coalfield in the internal economy of the Province. On the other hand, not nearly as well-known nor as frankly recognized is its significance in the national life of Canada, for from this field is produced not only 80 per cent of the Nova Scotia coal but over 40 per cent of all coal mined in the Dominion. Another noteworthy comparison can be made from the fact that the Sydney field contributes 22 per cent of all the bituminous coal consumed in Canada, the remainder being made up of 7 per cent mined elsewhere in Nova Scotia, 27 per cent from other parts of Canada (British Columbia and Alberta, principally), while the remaining 44 per cent is imported, practically wholly, from the United States of America.

Jan 1, 1941

By K. Adham, C. Lee

Over the last forty years, a number of specific fluidized bed applications in nickel extraction have been developed for commercial use. Five important processes have gained particular acceptance, namely, sulphide ore roasting, nickel sulphide (matte) roasting, nickel oxide reduction, laterite ore pre-reduction, and nickel chloride pyrohydrolysis. These applications involve different feed materials and process conditions, however, all benefit from fast reaction kinetics and high heat and mass transfer rates in the fluidized bed reactors. They have been studied, tested, and implemented by various nickel producers, who have published their results in many papers and patents. This paper examines the design issues surrounding the application of fluidized bed technology to the above nickel processes. Based on the available data in the open literature, computerized process modelling is used to provide generic flowsheets that illustrate the key features of each process.

Jan 1, 2004

By A. S. Bayne

WITH the great increase in the use of power-driven machinery in industry, and consequent large-scale operations, the hazards to which , workmen are exposed have become much more numerous than at the beginning of the century. This is especially noticeable in mining. In the past thirty years or so, improvements in methods of excavation and metallurgy have made possible the exploitation of deposits which would have failed to make ore in previous years. This improvement, together with the in-creased use of machinery, has facilitated the mining of tremendously greater tonnages with a marked decrease in unit cost of production. This 'speed up' in mining creates numerous problems demanding close attention of operators and necessitates careful prep;tratory planning, as well as diligent supervision of actual operations. Underground openings increase in size so fast, and all phases of mining, mucking, and transportation proceed at such a rate, that a short period of reduced vigilance on the part of operators . results in disaster, both from the standpoint of safety and economies. Happily, the challenge of increased hazards has been successfully met by a general application of the slogan 'Safety First'. Today, we have large manufacturing concerns devoted entirely to the development and production of safety equipment for the protection of workmen in various branches of industry. Machinery manufacturers, in co-operation with their mining customers, have included the best possible in foolproof devices in the manufacture of hoists, compressors, boilers, electric motors, and equipment of all kinds. Mining companies and private individuals spend thousands of dollars and devote a great deal of time to research with the single object of preventing accidents and combating miners? diseases. Governments throughout the world have written regulations into their statures for the protection of miners and operators. Staffs are appointed to enforce these laws and investigate accidents to ascertain means of preventing them for the future benefit of the industry.

Jan 1, 1938

By Marc C. Bétournay

Hydrogen fuelcells are a known technology, having been applied to stationary (e.g equipment, buildings, power plants) and vehicle applications (e.g transit buses, space shuttles). There is currently a growing need to provide alternate power systems to diesel fuel for underground mining vehicles to improve underground air quality and reduce production costs and green house gas emissions. To date, however, fuelcells have not been exposed to underground mine air and physical conditions. A testing program was carried out to provide information on the vulnerabilities of fuelcells as part of a number of proof-of-concept projects to apply hydrogen power to underground mining vehicles. The fuelcell type of choice for the industry, the Proton Exchange Membrane, would function at the range of temperatures encountered in underground and surface operations, and use hydrogen that is stored under low pressure and risk. A small fuelcell stack was tested in a cooperative project between CANMET, the Fuelcell Propulsion Institute, INCO, the Ontario Ministry of Labour, Sandia National laboratories and H-Power. This article will review the tests carried out to measure the effects from high humidity, mineral dust, diesel emission gasses and diesel particulate matter as well as from shock and vibration provided to the unit in underground conditions, at INCO?s 175 Orebody minesite and INCO?s Stobie Mine. The test results provided will show that the unit was not affected by the underground conditions: physically and electrically the unit performed without any reduction in operation or adverse effects imposed.

May 1, 2003

By Erwin L. Zodrow

"The neglect of including the toxic metal mercury in the list of escaping elements (Zodrow, CIM Bulletin, September 1982, pp. 138-140) was pointed out to the author in a private letter by J.E. Rehder, dated September 21, 1982. I welcome this opportunity to present my preliminary mercury research data based on coal investigations supported by N.S.E.R.C and the University College.As mercury is a volatile element and liquid at room temperature, special analytical techniques are required to determine concentrations in whole coal. In the investigation, the coal is analyzed by flameless atomic absorption with a lower detection limit of approximately 10 parts per billion, which, however, is a function of the ash contents of the coals (personal communication, J.L. Brooker, XRAL, 1981).Coal seams of the Sydney Coalfield studied so far include: the Point Aconi, a thin shaly coal, the Upper Bonar, an overrider of the Harbour seam, and the Harbour, Shoemaker and McAulay seams, all of which are shown in stratigraphic succession in Figure 1. The seams have been channel-sampled taking 15-cm coal intervals as one sample for analysis. One channel sample has been investigated from each of the seams listed (two channels were taken from the Point Aconi seam), resulting in 38 samples. Table 1 shows the results, which include mercury contents, ash and total sulphur per sample interval. Figure 2 is a frequency distribution of the 38 determinations."

Jan 1, 1982

By CIM Mineral Resource, Mineral Reserve Committee

These Leading Practice Guidelines for Mineral Processing (LPGMP) were prepared by the Sub-Committee on Leading Practice Guidelines for Mineral Processing. The Sub-Committee reports to the Executive Committee of the Canadian Mineral Processors (CMP) which is a Technical Society of the Canadian Institute of Mining, Metallurgy, and Petroleum (CIM) and incorporates those members of the CIM who are concerned with the processing of mineral deposits. The LPGMP covers the involvement of mineral processing professionals, referred to as Practitioners in this document, in providing inputs to the estimation of Mineral Resources and Mineral Reserves and providing technical content for internal reports as well as public reports on mineral projects as required under National Instrument 43-101 Standards of Disclosure for Mineral Projects (NI 43-101). The LPGMP supplement the CIM Exploration Practice Guidelines (2018) and the CIM Estimation of Mineral Resources and Mineral Reserves Practice Guidelines (2019) which are referenced in Companion Policy 43-101CP to NI 43-101 and recognized internationally. The LPGMP consist of 3 sections: • Principles of Process Support in Mineral Resources and Mineral Reserves Estimation; • Appendix A – Use of Supporting Studies in Process Evaluation and Assessment for NI 43-101 Documentation; • Appendix B – Glossary of Terms Relevant to the LPGMP. The LPGMP deal primarily with the description of leading practice as it applies to the mineral processing and extraction of base metals, precious metals, and other mineral products by the application of mineral processing technology. Other commodities may be considered with future updates of these guidelines. It is expected that this is a ‘living’ document and that these guidelines will develop in the future to address the requirements of the mining industry, investing public, and mining professionals involved. Clarifications and changes to these guidelines will be done under the guidance of the Executive Committee of the CMP.

Nov 25, 2022

By M. A. Upham

"MINING is Canada's second largest basic industry, producing material with a gross value of 2.5 billion dollars, led only by agriculture with 2.9 billion dollars. It pro-vides employment, directly and in-directly, for three quarters of a million people. Since the Second War, the value of mineral production in Canada has tripled. Economists forecast that over the next 15 years its value will triple again. Canada is a basic and leading supplier of nickel, iron, copper, zinc, lead and uranium. It is also a major oil producer, leads the world in the production of asbestos and in five years will be the leading producer of potash, a basic constituent of fertilizer.It can be seen that Canada's wealth and economic progress lies in being a primary producer of economic minerals and in building secondary industries to manufacture finished products from these raw materials. Canada's future in the field of mineral production looks bright, with our resources just starting to be tapped. Outside of the large expanse of Soviet Russia, we are by far the world's most fertile mineral exploration area."

Jan 1, 1967

By E. Pribonic

Failure of a mine material hoist can cause injuries, fatalities and significant infrastructure damage, along with an associated loss of production. Principal causes of hoist accidents are overwind and underwind. Past and present means of arresting hoisting equipment are marginally effective and utilize destructive systems that are not reusable following an arrest. The use of permanent magnet eddy current arrestor technology is proposed; the history and fundamental science of the technology are presented, followed by real world examples and calculations of performance for failsafe, friction-free, instantly reusable eddy current arrestors as applied to stopping a 30-ton ore skip traveling at 16 metres per second. A comparison of existing arrestor types with the eddy current arrestor is included and limitations of the ECA are also discussed.

Jan 1, 2008

By F. O. Verret

Several grindability tests were developed over the years to design grinding circuits or optimize existing operations. Each test has its own strengths and weaknesses and it is imperative to select the proper test procedure(s) to meet project deliverables and minimize the risk of a project. Pilot plant testing of large bulk samples historically constituted the traditional approach for AG or SAG design, but was gradually replaced by small-scale tests. Nowadays, conducting grindability tests requiring only a few kilos of material on several samples is a more typical approach to grinding mill design. This paper summarises the requirements and deliverables of various bench-scale test procedures, their strengths and weaknesses, and cases where AG/SAG pilot testing should still be performed.

Jan 1, 2012

By Tassos Grammatikopoulos, Sarah Prout, William Mercer, C. Gunning

"The Nechalacho rare metal deposit is located in NWT, Canada. Avalon Rare Metals Inc. is now evaluating processing techniques for recovery of REE to be used in the industry. QEMSCANTM analysis coupled with whole rock, REE, Zr and Nb, and electron microprobe analyses were utilized to identify and quantify the mineralogy of the deposit, and define the REE distribution among minerals. QEMSCANTM mineralogy was performed on fifty intact drill samples using EXPLOMINTM that provided textural information for the mineralization; crushed samples were used to determine the variability of the ore and define REE domains, and composite samples to determine the liberation and association of the REE minerals. The sample matrix predominantly consists of biotite, feldspars, quartz, muscovite/clays, minor chlorite and amphibole, magnetite and hematite and carbonates. REE include in decreasing order of abundance allanite (3.6%), monazite (1.5%), synchysite (0.9%), columbite (0.9%), fergusonite (0.6%), bastnaesite (0.4%), and zircon 11.0%. The majority of the HREE are carried by fergusonite and zircon, and the LREE by monazite, allanite, synchysite and bastnaesite. QEMSCANTM mineralogical data is extremely valuable in assessing the mineralogy of the ore. The data have been implemented in defining the mineralogy of the ore body, support metallurgical test work, predict recoveries and grades, and finally calculate reserves of the deposit.INTRODUCTIONAvalon is in the unique position of owning and developing one of the world’s largest rare earth deposits in the Northwest Territories of Canada.The term Rare Earth Elements (REE) is used to describe the 15 lanthanide elements or metals and, more recently, the metals yttrium and scandium, which display similar physical and chemical properties. REE are not particularly rare and have a similar abundance in the earth’s crust to nickel, tin or tungsten. Unlike these better known metals however, the rare earths have little tendency to become concentrated into commercial ore deposits. When they do become concentrated, deposits of REEs usually display enrichment in one of two groups. The most commonly occurring deposits of REEs contain a sub-group of elements referred to as the “light rare earth elements” (LREEs), which include lanthanum, cerium, praseodymium, neodymium, and samarium. Less commonly, deposits of REEs contain the much more valuable sub-group of elements referred to as the “heavy rare earth elements” (HREEs), which include europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium. Yttrium and scandium most commonly occur in association with this second HREE sub-group. Generally, LREEs are produced from the mineral bastnaesite, and the HREEs have been produced from the minerals xenotime and monazite. LREEs continue to be produced from bastnaesite, however in the 1980s, China started production of HREEs from unique laterite clay deposits. China now produces approximately 95% of the world’s rare earths."

Jan 1, 2011

By D. DeGagne, E. De Souza, J. F. Archibald

This paper describes the potential use of anew agent material for backfill consolidation, ground waste glass, to be used as partial replacement of Portland cement fractions within backfill. Significant fractions of commercial and residential silica glass production is currently utilized as waste landfill and must be disposed of at high cost and with no foreseeable environ-mental benefit. This paper also demonstrates that waste glass materials could be effectively recycled as backfill additives, and that a significant, large and stable source of additive supply, currently land filled, can be developed. This new application will generate added value for such materials, serve to promote positive environ-mental stewardship and satisfy engineering sup-port requirements in mines.

Jan 1, 1997

By Donald Leroux, Lori Lynn Smith, Robert Hutchison

"The grinding circuit of the Heath Steele concentrator was sampled under five different sets of operating conditions. The balanced results of the sampling campaigns were used to calibrate steady-state rod mill, ball mill and cyclone models using a commercial simulation software package (JKSimMet® ). Thirteen process variables had the potential to affect significantly the performance of the grinding circuit. Statistical-Design-of- Experiments techniques were applied to plan the suite of simulations in order to improve the quality of and minimize the time to find the optimal solution. The effect of each factor on three performance indices (the cyclone overflow size distribution, the circulating load and the cyclone underflow density) was modeled with empirical polynomial relationships using another software package (Design-Expert@)T. he conditions under which the cyclone overflow size distribution was maximized while respecting circulating load and cyclone density constraints were identified using these relationships. Among the most interesting results is the prediction of a set of conditions where the circuit target size distribution is achieved with only three ball mills instead of four.IntroductionProduction at the Heath Steele concentrator (near Miramichi, New Brunswick) started some 43 years ago at a rate of 750 t/d. The plant capacity was increased to 4000 t/d through successive expansion phases in the seventies (Sapiro, 1977; Johnston, 1978). However, as a result of depleting ore reserves, the plant throughput had to be gradually reduced to the current production rate of 2700 t/d. Heath Steele Mines currently have proven and probable reserves which would see it producing until the end of 1999 (Noranda Inc., 1997).An analysis of the grinding circuit of the Heath Steele concentrator was recently commissioned to identify opportunities for reducing operating costs while maintaining budgeted mill throughput and metallurgical performance. Since the plant will likely be operated below nominal capacity for the rest of its lifetime, the possibility of improving grinding efficiency by operating with fewer ball mills and/or crushers was contemplated."

Jan 1, 1999

By Steven W. Wilson, Brigitte Lacouture, Nichola A. McKay

"The Aqqaluk deposit is a lead-zinc ore body that lies immediately north of the Main Pit at Teck Cominco’s Red Dog Mine in Alaska. It is scheduled to begin production in 2011 or 2012. A project team was formed in late 2004 to plan and implement an ore characterisation and metallurgical evaluation on the Aqqaluk ore. The main objective of this program was to facilitate the transition from Main Pit to Aqqaluk ore in the Red Dog concentrator. The program will develop a detailed, spatially-oriented characterisation of the Aqqaluk deposit attributes including lithology, ore geochemistry, bulk mineralogy, ore texture, as well as evaluating the metallurgical characteristics of ore hardness, process water geochemistry, bench-scale floatability and mineral liberation in ground feed, concentrate and tails. Developing correlations between the metallurgical response and the ore characterisation data is key to the emerging science of geometallurgy. This on-going program is a technical due diligence study that aims to reduce the risk associated with processing a new ore and to provide predictive information for mining and stockpile preparation.The test work to date has focused on characterising the five ore zones currently identified in the Aqqaluk deposit, namely: Siliceous (sub-divided to High Zn:Fe and Low Zn:Fe), Vein, Median Plate and Baritic ores. It identified a number of challenges associated with surface oxidation, or weathering, of the core samples and outlined a program for future sample collection and storage. Metallurgical testing evaluated ore hardness by a variety of methods. Preliminary floatability studies have been completed and some initial links have been established between the ore characteristics and the flotation response. Soluble mineral weathering products, the relative abundance of pyrite and marcasite and the iron content in the sphalerite grains have all shown a correlation to mineral recovery.As new core is received, both the ore characterisation and the metallurgical testing will be continued with a view to strengthen the existing correlations and develop new links."

Jan 1, 2007

By F. Halverson

"The theory of flocculation usually is in a state of flux, involves many diverse phenomena, and is complex and sometimes contradictory in details. Instead of attempting a general discourse, I shall discuss selected observations made at our Stamford Laboratories, which impinge on theoretical aspects in two somewhat distinct areas of flocculation. Since some of you many not be familiar with flocculation, and :.n order that we all attach the same meaning to the jargon used, I first would like to review briefly a generalized picture of what goes on.Assume we have a suspension of particles in water, with a distribution in the sizes of particles. The surfaces of the particles interact to some extent with the water--· tending to alter the extent of hydration, may generate some ion exchange, all being somewhat variable with time--developing a surface condition which is very complex in details. We refer to this suspension as the ""substrate.""In the usual situation, if the suspension is allowed to stand quietly, the large particles settle out first, with somewhat smaller particles settling more slowly, and then there is a portion of very fine material which takes a long time or doesn't settle out at all. This resistance to settling t~ the very fine particles results from many factors, but all relate back to the size and density of the particles, to their surface properties, and to the other components in the aqueous suspending medium."

Jan 1, 1978

By J. Duncan Crone

"A test surface Pulse EM(PEM) survey over a plunging massive sulphide lens, located in the Snow Lake area of Manitoba, has shown that it is possible to detect the body to a depth of 300 metres. Another surface survey in the Athabasca basin of Saskatchewan, clearly outlined a large, basement graphitic zone below 450 metres of sandstone cover. Deep detection of these conductive bodies was achieved by energizing large volumes of ground with a strong transmitted EM field. Such large fields also energize all other conductors present in the exploration area. Both of the above survey results indicate that more than one conductor is present. In such cases, detailed field coverage is required for accurate interpretation, and interpretational procedures that assume simple geometrical shapes should be applied with caution. In all cases geological and geophysical information should be coordinated in detail. The first test drill hole still has a high risk of missing the deep conductive body and two or three holes should be budgeted per target.Borehole Pulse EM surveys are now routinely used to help zero in on deep conductive targets. They are also proving effective in development drilling programs by outlining the edges of conductive bodies. The results of surveys from northern Quebec illustrate how they may provide more accurate shape and tonnage estimates."

Jan 1, 1985

By J. G. Henning

Following completion of planned mining operations at the Goldcorp Dome Open Pit Mine, a high-grade Shaft Pillar located in the pit highwall was recovered. Mining of this Shaft pillar faced numerous rock engineering design and implementation challenges due to its remote position on the highwall and the presence of mine workings within the wall. The case example presented in this paper discusses the geotechnical investigation performed at the site, novel measures undertaken for installation of ground support required for rockmass reinforcement and for worker protection, as well as operational challenges to successful mining of the Shaft Pillar.

May 1, 2009

By Paul Armstrong

THE first discovery of lead and zinc ore on Calumet island was made in 1893 by John Lawn, who then staked a portion of the property now owned by Calumet Mines, Limited. His discovery was developed by James and Calvin Russell, who are said to have shipped a few tons of sorted ore, averaging 39 per cent zinc, 13 per cent lead, and 11 oz. silver per ton. In 1898, the property was being operated by the Grand Calumet Mining Company, who mined and shipped, for treatment in a Belgian smelter, 1,100 tons of ore averaging 32 per cent zinc, 9 per cent lead, and an unreported content of gold and silver. After some indecisive exploration by an American syndicate in 1907, the property lay idle until1910, when the Calumet Metals Company-later reorganized as the Calumet Zinc and Lead Company-re-commenced exploration. After sinking an 85-foot shaft-the McDonald shaft-and doing a few hundred feet of drifting and cross-cutting, this Company, in 1912, erected a 150-ton daily capacity gravity-concentration plant, in which some 800 tons of ore, mined from the McDonald shaft and Bowie pit, were milled. Owing to very disappointing mill recoveries, the property was shut clown and-after several years of idleness-in? 1916 the mill and mining plant were destroyed by fire and the Company went into bankruptcy. In 1918, an unknown operator shipped to an Omaha, Nebraska, smelter 22 tons of ore, probably sorted from the dumps of the Ste. Anne shaft and Galena pits, averaging 44 percent lead, and 0.26 oz. gold and 61 oz. silver per ton. The British Metals Corporation (Canada), Limited, in 1926, optioned the property. They unwatered the McDonald shaft and, after doing an additional 300 feet of cross-cutting and drifting on the 85-ft. level, estimated there were some 33,000 tons of ore between this level and the surface. Surface exploration, including trenching, on other showings on the property gave discouraging results and the option was dropped.

Jan 1, 1941

By D. J. McLaren

"Arctic Canada is one of the largest undeveloped terrains remaining in the world, and is in many ways unique. The ecological balance of the region is more delicate than tropical or temperate regions of similar size. This region is likely to be developed by research for and production of resources, primarily petroleum, in the immediate future. As well as sensitive terrain surface caused by permafrost in some areas, many large and small mammals and birds are also in a delicate balance with the environment. Small changes in this balance can have large effects.The probability of finding petroleum in different regions varies widely, but already there are good indications on the mainland and in the Islands that both oil and gas are present. Geophysical work in the offshore, particularly the Beaufort Sea, suggests further promising potential. Possible reserves in the Islands and mainland Arctic may amount to 50 or more billion barrels.A responsible approach to problems facing exploitation in an Arctic environment includes the careful monitoring by industry of likely effects of their activities. The Mackenzie Valley Pipeline Research Association test loop at Inuvik provides an example of such monitoring. Outside Canada, the operations at Prudhoe Bay on the north coast of Alaska show how major companies may operate responsibly and reduce environmental interference to a minim'.::at. Nevertheless, four variables must affect any decisions to be made concerning energy resource exploitation in the Arctic. These are man's need for energy, economic and industrial pressures to develop energy sources, the desire to preserve a deteriorating environment, and the role of government as representing all individuals in the country and their several points of view. Factors that must be taken into account in making any decisions include the importance of Canadian oil in a world picture, the need for alternative sources of energy in the near future, the depletion of nonrenewable resources at an accelerating rate and the increasing awareness that the major problems facing man have no direct technical solution and that social or political decisions must precede further techno-logical development."

Jan 1, 1971

By Mario Bergeron

L'exploration géologique pour les EOP (EOP: platine, palladium, iridium, osmium, ruthénium, rhodium) requiert avant tout des méthodes appropriees à la mesure de ces élémenIs. L'approche analytique choisie doit tenir compte de plusieurs facteurs, les plus importants étant: le type de materiel analysé, sa representativite, la sensibitite de la methode et les cotits reliés à son utilisation. Dans cette optique, plusieurs démarches ana/ytiquessont possibles, toutes requérant une étape de préconcentration. L 'une des plus adéquate consiste à effectuer une préconcentration par fusion plombeuse suivie d'une analyse par émission au plasma, cette procédure permettant de mesurer Ie platine, la palladium et Ie rhodium à des couts compétitifs (15 $/échantillon). Advenant 10 presence de teneurs appréciables de l'un ou plusieurs de ces éléments, une préconcentration par fusion au sulfure de nickel suivie d 'une analyse par activation neutronique assure alors la mesure de tous les EGP ainsi que celie de l’or (90 $/échantillon). Il est important de noter que Ie nickel, ades teneurs superieures à 4%, interfère au cours de l'étape de préconcentration par fusion plombeuse, ce qui se traduit pas sous-dosage des concentrations en platine, effectivement presentes dans l'échantillon. Ainsi, les géologues à la recherche d'EPG dans des environnements géologiques riches en nickel devraient s'assurer que l'analyse utilise, au cours de l'étape de préconcentration, une fusion au sulfure de nickel.

Jan 1, 1990