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By I. Peerawattuk

Growing demand for Li-based battery technologies is leading to an unprecedented growth in the lithium industry. Although innovation in battery technologies has pushed lithium into the spotlight, lithium was not always known for its application in batteries. The primary use of lithium—prior to the introduction of commercial lithium-ion batteries in the early 2000s—was in the ceramics, glass, grease, and the medical industry. Before being converted into usable forms, lithium products must be upgraded from the raw material. Processes for recovering lithium may involve: thermal treatment, water leaching, solar evaporation, ion exchange, carbonation, and electrodialysis. Presented, is a historical review of lithium applications and the different techniques of converting lithium-rich minerals and brines into usable products with additional discussion on future lithium extraction processes.

By Louis J. Czel

Although lithium was first discovered by Arfwedson in Sweden in 1817, it did not reach any significant status in commercial application until 1908 when Thomas A. Edison received a patent covering the use of lithium hydroxide in alkaline' storage batteries. Edison's achievement can be regarded as a major breakthrough in the development of the lithium industry. In the years prior to 1908 lithium salts had found only modest applications in the pharmaceutical and pyrotechnic fields. The next important milestone in the growth of this net industry occurred in Germany in 1918 when Metallgesellschaft at its metallurgical laboratory at Frankfort-on-Main discovered that the addition of a few hundredths percent of lithium metal to aluminum and its alloys increased-the hardness. This brought into being a new commercial use of lithium in the manufacture of bearing metals. The new material, called "Bahnmetall" (railroad, metal), was widely used for, many years in the manufacture of bearings for railroad and automotive purposes. Its use continued until the early 1930's and there was a short-lived renewal of its production during World War II. Subsequent use of-the alloy was soon outmoded.

Jan 1, 1961

By N Setoudeh, A Nosrati, N J. Welham

The current surge of interest in lithium (Li) is due to the anticipated demand for electric vehicles and small scale power storage. Brine deposits contain most of the global Li resource, however hard rock deposits can be more readily and rapidly developed and comprise the majority of proposed projects. These projects plan to use the conventional processing routes of dense medium separation and / or flotation to produce a spodumene concentrate for sale. The standard route for subsequent processing of spodumene concentrate is thermal decrepitation, acid leaching, solution purification and precipitation of lithium carbonate. This is typically followed by further purification. A number of projects have ores which contain other lithium minerals, principally micas, lepidolite and zinnwaldite, necessitating an alternative treatment route. Several different routes for spodumene processing are under development to reduce costs to compete with brine projects. This paper will give an overview of the strengths and weaknesses of the current and alternative processes.CITATION:Welham, N J, Nosrati, A and Setoudeh, N, 2017. Lithium ore processing – an overview of the current and new processes, in Proceedings MetPlant 2017, pp 185–194 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By MAX VOS

Lithium is the lightest and electrochemically most reactive of all metals. Renewed interest in lithium coincides with research in lithium batteries and power generation by atomic fusion. Ontario lithium resources are contained in spodumene pegmatites that can form where medium- to high-grade metamorphic volcanic-sedimentary formations are intruded by pegmatite and porphyritic granitic rocks. Spodumene pegmatites occur in at least twelve locales throughout northern Ontario, all of which are in the Superior Province of the Precambrian Shield. Tantalum, cesium, rubidium, beryllium, niobium and tin also were noted with lithium in spodumene pegmatites. Considerable potential remains for discovery of additional lithium and rare-element pegmatites in northern Ontario.

Jan 1, 1984

By Ihor A. Kunasz

Introduction Lithium minerals occur predominantly in pegmatites which contain mineral assemblages derived from the crystallization of postmagmatic fluids or from the metasomatic action by residual pegmatitic fluids. They have been the traditional sources of raw materials for ceramic and chemical industries. With the discovery of Searles Lake, brines became new sources of lithium. Indeed, the 1960s may well be referred to as the "brine decade" because several brine bodies of significant economic importance were discovered. In the United States, the brines of Clayton Valley, Nevada, are presently exploited by Foote Mineral Co. The brines of the Great Salt Lake of Utah, the Smackover formation, and the Imperial Valley geothermal field, have been defined as important resources of lithium. In South America, new occurrences have been identified in Bolivia and Argentina. At the Salar de Atacama, Chile, new production capacity is scheduled for 1984. Following the termination of the AEC purchase program in 1959, several companies such as Maywood Chemical Co., American Lithium Chemicals, and Quebec Lithium Corp. were forced to close their operations. Nevertheless, with the development of new applications in glass ceramics, air conditioning systems, synthetic rubber, and metallurgy (aluminum potlines), the lithium industry grew steadily, and with the potential application of lithium metal in batteries and nuclear reactors, a healthy growth can be foreseen. New products and new applications are likely to stimulate exploration for expanded, reserves as well as the search for new sources from which lithium could be extracted economically. Geochemistry of Lithium Lithium is the third element in the periodic table. It is the lightest of all the metals, having an atomic weight of 6.938, an ionic radius of 0.68Å and a charge of +1. The geochemistry of lithium has been extensively studied and has been summarized by Rankama and Sahama (1950), Goldschmidt (1937), and Hortsman (1957). The distribution of lithium in igneous rocks is controlled by its size and its charge, and by the (MgO+FeO) / Li2O ratio. In the early stages of crystallization of a magma, that ratio is very large. Consequently, both magnesium and iron are removed by ferromagnesian minerals in preference to lithium which is then concentrated in the residual magma. This results in an enrichment of lithium in silicic rocks and pegmatites (Strock, 1936). Pegmatites are coarse-grained igneous rocks formed by the crystallization of postmagmatic fluids. Minerals within pegmatites may also form by metasomatism (Jahns, 1955). Genetically, the pegmatites are associated with neighboring intrusives. Mineralogically, granitic pegmatites contain feldspar, quartz, and mica as the main constituents and a variety of exotic elements such as lithium, beryllium, tantalum, tin, and cesium, which may or may not occur in economically significant concentrations. Detailed studies by numerous investigators (Cameron et al., 1949, 1954; Hanley et al., 1950; Jahns, 1953, 1955; Page et al., 1953) indicate that pegmatites often exhibit an internal zonal arrangement, with each zone containing a specific suite of minerals. The lithium minerals are usually found in the intermediate zones, and although as many as 13 zones have been recognized by Cameron, et al. (1949), a complete zonal arrangement is rarely found. Zoning of pegmatite bodies has also been observed on a regional basis. The regionally zoned pegmatite sequences exhibit mineral assemblages and complexity according to their re-

Jan 1, 1983

By Ihor A. Kunasz

Lithium minerals occur predominantly in pegmatites that contain mineral assemblages derived from the crystallization of post- magmatic fluids or from the metasomatic action of residual peg- matitic fluids. They have been the traditional sources of raw material for ceramic and chemical industries. With the discovery of the Searles Lake deposits, brines became new sources of lithium, and, today, two brine deposits satisfy nearly one-half of the free world demand for lithium chemicals. Indeed, lithium production from pegmatites has been superseded by brines sources. In the United States, the brines of Clayton Valley, NV, have been exploited since 1964 by Cyprus Foote Mineral Company, a subsidiary of Cyprus Minerals Company. In Chile, Sociedad Chilena de Litio Ltda., an affiliate of Cyprus Minerals Company, is now producing lithium carbonate from the brines of the Salar de Atacama. Recently identified brine deposits suggest that these may well become the prime sources of lithium chemicals. In Bolivia, the government is negotiating the rights to exploit the brines of the Salar de Uyuni. The Salar del Hombre Muerto in Argentina is being evaluated as a future center of chemical production. The brines of the Great Salt Lake of Utah, the Smackover Formation, and the Imperial Valley geothermal field have been defined as important resources of lithium. In Tibet, high concentrations of lithium have been reported in several saline lakes. In the People's Republic of China, lithium may be produced from the brines of the Dabusan playa in the Qinghai Basin. The 1950s saw a great number of lithium companies develop. However, following the termination of the Atomic Energy Commission purchase program in 1959, several companies, such as Maywood Chemical Co., American Lithium Chemicals, and Quebec Lithium Corp., were forced to close their operations. Nevertheless, with the development of new applications in glass ceramics, air conditioning systems, synthetic rubber, and metallurgy (aluminumpotlines), the lithium industry grew steadily. With the potential application of lithium metal in batteries, nuclear reactors, and fuel cells, a steady growth can be foreseen. New products and new applications are likely to stimulate exploration for expanded reserves as well as the search for new sources from which lithium could be extracted economically. Presently identified reserves and production capacity are sufficient to satisfy the conventional market growth of lithium.

Jan 1, 1994

By Linda Gaines

Use of vehicles with electric drive, which could reduce our oil dependence, will depend on lithium-ion batteries. But is there enough lithium? Will we need to import it from a new cartel? Are there other materials with supply constraints? We project the maximum demand for lithium and other materials if electric-drive vehicles expanded their market share rapidly, estimating material demand per vehicle for four battery chemistries. Total demand for the United States is based on market shares from an Argonne scenario that reflects high demand for electric-drive vehicles, and total demand for the rest of the world is based on a similar International Energy Agency scenario. Total material demand is then compared to estimates of production and reserves, and the quantity that could be recovered by recycling, to evaluate the adequacy of supply. We also identify producing countries to examine potential dependencies on unstable regions or future cartels.

Jan 1, 2010

By Ali Tabeshian, Ragnhild E. Aune, Reza Beheshti

Today’s lithium-ion batteries (LiBs) are found in more than half of the hybrid-electric and plug-in hybrid vehicles on the marked, all-electric vehicles, and nearly all consumer electronics. As a result, recycling of LiBs will be a strategic necessity in the near future. In the present study, the feasibility of application of conventional aluminum recycling process (secondary aluminum production) as a suitable process for treatment of LiBs was studied. The overall idea is to recover aluminum, copper and lithium from a mixed waste stream of LiBs and aluminum scrap. A two-stage process, consisting of a preheating step and a melting step, were tested on cell phone batteries mixed with pure aluminum in a ratio 1:10 and the distribution of elements between the metal phase and the slag phase evaluated. The obtained results are compared and discussed based on the thermodynamic calculated by the use of the FactSage™ software version

Mar 1, 2017

By L. Yuan, C. Brown, N. Rayyan, J. Soles, T. H. Dubaniewicz

As lithium-ion batteries (LIBs) become more prevalent in the mining industry, new hazards of battery fire and explosion are emerging. Efforts must be taken to ensure that workers are safe from these new hazards, such as batteries undergoing thermal runaway in underground areas that may have explosive methane-air mixtures. Researchers at the National Institute for Occupational Safety and Health (NIOSH) investigated overpressures generated within a sealed battery enclosure filled with an explosive methane-air mixture and a single cell lithium-ion battery driven into thermal runaway using an accelerating rate calorimeter (ARC). For both iron phosphate (LFP) and nickel manganese cobalt (NMC) lithium-ion cells, the explosion overpressures remained unchanged with varying percentages of methane concentration in the atmosphere surrounding the cell. It’s likely that the gases released from the battery undergoing thermal runaway caused an inert atmosphere within the sealed canister. The results from this study will help mining equipment manufacturers develop proper measures to keep miners safe while working with lithium-ion batteries in underground gassy mines

Mar 2, 2022

By D. J. McCracken

During 1995, the estimated consumption of lithium minerals in the western world was 139 kt (153,000 st).This amounted to 18 kt (20,000 st) of lithium carbonate equivalent (LCE). Overall tonnage demand for lithium minerals increased by 10.8 kt (11,900 st) during 1995from 1994. From 1992 to 1995, overall tonnage demand has increased 62%, from 85.5 to 139 kt (94,240 st). There are four major producers of lithium minerals. Gwalia Consolidated in Western Australia is the largest producer of spodumene. It supplies high-grade spodumene concentrate, fine-spodumene concentrate, glass-grade spodumene and chemical-grade spodumene.Tantalum Mining (Tanco) of Manitoba, Canada, produces high-grade spodumene concentrate, fine-spodumene, concentrate and montebrasite. Bikita Minerals in Zimbabwe is the largest manufacturer of petalite. It supplies high-grade and container-glass petalite.

Jan 1, 1996

By M. Tamlin

The state of the lithium mineral industry is closely linked to the performance of the glass and ceramic industries and to the overall economy. Demand for the glass/ceramic products in Europe, Asia and North America remained strong during 1999. This was due to a slight improvement in the economy during the latter half of the year. Consequently, demand for lithium minerals was firm, with a positive outlook. The major economic minerals for lithium are spodumene, petalite and lepidolite. The latter was once the primary mineral. But its importance hasdeclined since the 1960s. The lithium industry consists of two different segments: •The lithium minerals segment mines from hard-rock deposits and physically processes the material to high-grade concentrates. •The lithium chemicals and metal industry segment. The major feedstock for specialty lithium chemicals was previously high-grade spodumene ore converted to lithium carbonate. However, most lithium carbonate is now sourced from salars in North and South America.

Jan 1, 2000

By Charles Taschereau

The statements made in this presentation contain certain forward-looking statements concerning potential developments affecting the business, prospects, financial condition and other aspects of Canada Lithium Corp. The actual results of the specific items described in this presentation, and the company?s operations generally, may differ materially from what is projected in such forward-looking statements. Although such statements are based upon the best judgments of Canada Lithium Corp. management as of the date of this presentation, significant deviations in magnitude, timing and other factors may result from business risks and uncertainties including, without limitation, the Company?s dependence on third parties, general market and economic conditions, technical factors, the availability of outside capital, receipt of revenues and other factors, many of which are beyond the control of the Company. Canada Lithium Corp. disclaims any obligation to update information contained in any forward-looking statement. Toronto Stock Exchange: CLQToronto CLQOTCQX: CLQMFOTCQX: CLQMF

May 1, 2011

By Hans E. Madeisky, Bruce W. Downing

Abstract-The acid rock drainage (ARD) buffering capacity of mine waste is governed by its bulk chemical composition and its mineral assemblage. Conventional acid base accounting (ABA) tests can be used to predict short-term buffering, but should be used with caution to model or predict the long-term ARD buffering capacity of mine waste. ABA data for mine waste samples from four different deposit types: anorthosite-hosted magmatic sulfide nickel, dunite-hosted magmatic sulfide nickel, porphyry copper-gold, and volcanic-hosted high sulfidation epithermal silver, were compared with whole-rock geochemical and petrographic data obtained from the same samples. Our objective was to devise and test a method of predicting ARD buffering capacity based on bulk chemistry and modal mineralogy. In other words, we developed a quantitative theoretical method for calculating neutralizing potential, relying on easily obtainable and relatively inexpensive whole-rock and sulfur XRF analyses, which could substitute for conventional ABA procedures in situations where these procedures are either too costly or too time consuming. For each deposit type, models were devised that reasonably approximate the net neutralization potential estimated by the ABA data obtained from laboratory tests. Once an appropriate model has been developed and tested, portable X-ray fluorescence equipment, already used for grade control at many mine sites, could provide the wholerock and sulfur analyses required to estimate the ARD potential of the waste material. Although this approach is not intended as a substitute for the legally mandated ABA test procedure, it could facilitate the timely and cost-effective management and mitigation of ARD at a mine site.

Jan 1, 1997

By Hans E. Madeisky, Bruce W. Downing

The acid rock drainage (ARD) buffering capacity of mine waste is governed by its bulk chemical composition and its mineral assemblage. Conventional acid base accounting (ABA) tests can be used to predict short-term buffering, but should be used with caution to model or predict the long-term ARD buffering capacity of mine waste. ABA data for mine waste samples from four different deposit types: an orthosite-hosted magmatic sul?de nickel, dunite-hosted magmatic sul?denickel, porphyry copper-gold, and volcanic-hosted high sul?dation epithermal silver, were compared with whole-rock geochemical and petrographic data obtained from the same samples. Our objective was to devise and test a method of predicting ARD buffering capacity based on bulk chemistry and modal mineralogy. In other words, we developed a quantitative theoretical method for calculating neutralizing potential, relying on easily obtainable and relatively inexpensive whole-rock and sulfur XRF analyses, which could substitute for conventional ABA procedures in situations where these procedures are either too costly or too time consuming. For each deposit type, models were devised that reasonably approximate the net neutralization potential estimated by the ABA data obtained from laboratory tests. Once an appropriate model has been developed and tested, portable X-ray ?uorescence equipment, already used for grade control at many mine sites, could provide the whole-rock and sulfur analyses required to estimate the ARD potential of the waste material. Although this approach is not intended as a substitute for the legally mandated ABA test procedure, it could facilitate the timely and cost-effective management and mitigation of ARD at a mine site.

Jan 1, 1997

By H. Ranjbar

The Darrehzar porphyry Cu deposit is situated in the Urumieh-Dokhtar magmatic suite of Central Iran. The REE and trace element data suggest that the deposit lies within a continental margin setting. Phyllic and propylitic alteration are pervasive in the area but potassic and argillicalteration are not readily recognized on the surface. This is possibly the result of super gene weathering of the surface rocks or because of an intense phyllic overprint. Poor soil development and abundant outcrop make the area suitable for a case study of lithogeochemical exploration technique for Cu deposits. A total of 262 rock samples was collected over the area and analyzed for 15 elements. The geochemical data cor-relate with the mineralogical composition of the rocks with the phyllic zone being marked by high-er concentrations of Si, Al, K, and by a high sericitization index while Ca, Mg, Sr, total Fe and Mn are more abundant in the propylitic zone. The lithogeochemical study indicates a metal zonation from a Cu + Mo-rich core to a Zn + Pb ± Ag-rich outer zone. Principal component analysis is useful for separating element associations, which in turn reflect the alteration halos. Principal components 1 and 2 depict alteration zoning, where-as 3 shows an association of Cu and Mo, that roughly defines the mineralized area.

Jan 1, 1997

By L. K. Mireku

"Abstract - The Halfmile Lake South Deep zone, Bathurst Mining Camp, New Brunswick, was discovered by Noranda Inc. (Exploration) as a result of a 3-D seismic survey in 1998 and the subsequent drilling of ten diamond-drill cores. The deposit consists of massive, breccia, and stockwork Pb-Zn-Cu sulfide minerals, and is hosted by a volcano-sedimentary sequence belonging to the overturned Ordovician Tetagouche Group. Epiclastic rocks and interbedded fine-grained felsic pyroclastic rocks dominate the stratigraphic footwall. Locally, crystal-rich felsic tuffs and subordinate epiclastic rocks comprise the immediate stratigraphic hanging wall. The entire stratigraphic sequence was intruded by quartz-feldspar porphyritic intrusions, and cut by intermediate and basic dikes. The volcanic and sedimentary rocks can be discriminated geochemically using trace element ratios such as Zr/TiO2 and Nb/TiO2, despite intensive alteration and cleavage development. These ratios indicate that four protolith volcanic compositions exist: rhyolite, dacite, andesite, and basalt. The aphyric and feldspar- and quartz-phyric volcanic rocks are dacitic and rhyolitic in composition; epiclastic rocks have trace element ratios consistent with dacitic compositions. Pearce element ratio diagrams, general element ratio diagrams, and petrographic observations demonstrate that the rhyolitic volcanic rocks exhibit evidence of albite, potassium feldspar, and quartz fractionation, dacitic volcanic rocks exhibit little evidence of any fractionation, and epiclastic sedimentary rocks exhibit evidence of quartz sorting only. Hydrothermal alteration is best represented by the presence of phengitic muscovite and daphnitic chlorite. Minor calcite occurs in the stratigraphic hanging wall, deep in the stratigraphic footwall, and in post-mineralization dikes, and thus is not interpreted to be part of the causative hydrothermal event. Element additions and losses during alteration have been used to determine net alteration reactions, and these have been used to identify alteration parameters that are independent of other forms of alteration and fractionation/sorting, and which can be used to guide exploration. These parameters include: a bulk hydrolysis measure, (2Ca+Na+K-2CO2)/Al; a muscovite alteration measure, K/Al; an albite destruction measure, Na/Al; a chlorite alteration measure, (Fe+Mg-S/2)/Al; a chlorite composition measure, (Fe-S/2)/Mg; a sulfidization measure, S/Ti; and a carbonatization measure, CO2/Ti. With the exception of the carbonatization measure, these alteration parameters define a distinct lateral and vertical zone of intense hydrothermal alteration in the stratigraphic footwall of the deposit, and demonstrate that the epiclastic rocks are predominantly chlorite altered, and the volcanic rocks are predominantly muscovite altered. Within the alteration halo, element additions of Fe and H, and element losses of Na are characteristic. Potassium was added to muscovite-altered rocks, but subsequently removed from chlorite-altered rocks. The results from this study demonstrate that metamorphism and deformation have not significantly obscured hydrothermal alteration signatures."

Jan 1, 2006

By V. J. Sopuck, O. P. Lavin, Ian Nichol

"A major challenge of contemporary exploration geochemistry is the development of procedures that can locate blind mineralization or mineralization that sub-crops below a cover of transported overburden, the composition of which bears no relation to the underlying mineralization. Over the past few years, the possible existence of diagnostic geochemical features in the country rock associated with volcanogenic massive sulphide deposits has attracted increasing attention both on the local mine scale and on the regional scale. In the present investigation, the nature of the geochemistry of a number of Archean greenstone belts of the Canadian Shield is examined to determine the feasibility of distinguishing productive from non-productive areas of copper-zinc mineralization. The results indicate that productive areas are distinguishable from non-productive areas providing consideration is given to the effects of igneous differentiation on rock compositionIntroductionArchean massive sulphide deposits are an important source of copper and zinc, and to a lesser extent silver and gold, particularly in Canada. As in the case of most other forms of mineralization, there is a continual need to develop new techniques that will improve the chances of success in the search for these deposits. The majority of Archean areas in the northern latitudes are overlain by a variable cover of glacial overburden. Considerable progress has been made in the development of new geochemical exploration techniques for use in glaciated terrain, based on the detection of anomalous dispersion in the glacial overburden. In certain situations, however, as in the search for blind deposits or in areas covered by glaciolacustrine deposits, overburden geochemistry offers little hope for success. In the case of massive sulphide deposits, one possible solution may lie in the detection of anomalous geochemical signatures in the bedrock. Recognizing this possibility, attention has been directed to the investigation of the nature of lithogeochemical dispersion associated with massive sulphide deposits on both regional and local scales, to establish the potential of lithogeochemistry as an aid in the search for these deposits."

Jan 1, 1980

Ancient volcanogenic Cu-Zn-Pb-Ag-Au massive sulfide ores commonly have associated with them along strike and in the immediate hanging wall a distinctive sediment that is thin, usually cherty and metal enriched, and generally referred to as an "exhalite horizon" or "tuffaceous exhalite". Typical examplks include the 13 Ma tetsusekiei of the Kuroko deposits of Japan (Kalogeropoulos and Scott, 1983, Econ. Geol.) and the 2700 Ma contact tuffs of Noranda, Canada (Kalogeropoulos and Scott, 1989, Can. J. Earth Sci.) and Key Tuffite of Mattagami, Canada (Liaghat and McLean, 1992, Explor. Min. Geol.). Attempts to use trace element distributions as lithogeochemical guides to ore have been largely unsuccessful. Exhalites have been considered to be the products of seafloor hydrothermal activity that is peripheral to the main ore-producing vents. However, large actively-forming polyrnetallic sulfide deposits at the Explorer mid-ocean basalt spreading ridge (1 850 m depth) in the NE Pacific and the eastern Manus back-arc dacitic spreading center (1650 m depth) in the western Pacific have demonstrated that the exhalite horizons are more likely produced by fallout of particulates from the main hydrothermal plume. In a typical hydrothermal plume, grains of >27 µm represent up to 97% of the mass (although only 2% of the population) of the particulates and are calculated by Stokes equations to fall from the plume to the seafloor within a few krn of their source. The particles are primarily composed of anhydrite, barite, amorphous silica, iron oxyhydroxides and metal sulfides and oxides. Plumes are subject to bottom currents which push them in preferred directions, just like smoke plumes in the atmosphere are subject to the vagaries of wind direction. Bottom currents in the deep ocean can be 50 m/min or

Jan 1, 1993

By P. Trudel, M. A. . Cloutier

This lithogeochemical study demonstrates that the Gilman and Blondeau Formations in the Chibougamau area belong to a subalkaline suite of tholeiitic affinity poor in potassium. The Gilman Formation is composed mostly of basalts, with subordinate andesites and rare dacites, while the Blondeau Formation comprises all lithologies of the basalt-andesite-dacite-rhyodacite-rhyolite ensemble. Both AFM and Harker variation diagrams show that all these rocks originated by differentiation from the same magma reservoir, and are related to one volcanic episode, This study did not, however, identify hydrothermal alteration zones useful for regional geochemical prospect ion.

Jan 1, 1984

By Michel Mellinger

This paper presents preliminary results of a project aimed at obtaining a better understanding of the genesis of gold mineralization in northern Saskatchewan using lithogeochemistry. The properties sampled were: Weedy Lake (B Zone), Waddy Lake (Komis Zone) and Wedge Lake (Twin Zone) in the La Range belt, and the Rio mine in the Flin Flon area. Although the three vein-type deposits rudied here (Weedy Lake. Waddy Lake, Rio deposit) occur in different geological situation . a common gold deposition mechanism appears to have been active at all three location . Hydrothermal fluids carrying sulphur in solution in exces of gold thio-complexes moved through fractured host-rocks until they reached a site where pyrite precipitation wa triggered. As pyrite precipitated, the a/ aAu activity ratio of the fluid decreased. until a critical thre hold was reached and gold thio-complexe were de tabilized . resulting in the co-precipitation of gold and pyrite. The conditions triggering the precipitation of pyrite appear to have been: the abundance of iron in host-rock ~ilicates at Waddy Lake. and temperature decrease upon the reaching of structural trap~ at both Weedy Lake and the Rio deposit. with additional involvement of carbonatizationrelated reactions between fluid and host-rocks for the latter. In addition to pyrite precipitation , potassic alteration of the mafic metavolcanics is observed at Waddy Lake. while at the Rio deposit, the extensive carbonatization of the host-rocks i coupled with the deposition of chlorite that may have been remobilized from the altered mafic host rocks. In both the B Zone at Weedy Lake and the Komis Zone at Waddy Lake, a di tinct vanadium signature give some clue about the direction in which the hydrothermal fluids have moved . and the interpretation made is con istent with the geological ituation in either case. As for the Wedge Lake deposits, the distinct base metals-precious metals a sociation within a sulphide-facies iron formation confirm the volcanic exhalative origin of this gold mineralization .

Jan 1, 1986