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Brucite – Industrial Mineral with a Future George J Document generated on 10/01/2021 8:12 p.m. Geoscience Canada Brucite – Industrial Mineral with a Future George J. Simandl, Suzanne Paradis and Melanie Irvine Volume 34, Number 2, June 2007 Article abstract Brucite, Mg(OH)2, is an uncommon mineral primarily known to mineral URI: https://id.erudit.org/iderudit/geocan34_2art01 collectors, and to specialists studying contact metamorphic and ultramafic rocks. It is an environmentally friendly flame-retardant and is in commercial See table of contents demand; it also represents a potential ore source for the metal, magnesium, which is itself in great demand. The present brucite market for flame-retardants is less than 50 000 tonnes annually, but it is increasing Publisher(s) exponentially. Brucite has the advantage of not containing CO2; hence none is released during calcination, a positive feature in today’s society concerned The Geological Association of Canada with climate change. This review paper summarises the topic for scientists studying the thermodynamic properties of brucite, geologists studying its ISSN contact meta-morphic characteristics, exploration geologists and potential end-users. Given the demand for the mineral and metal, high-grade brucite 0315-0941 (print) deposits may become hot exploration targets within the next few years. 1911-4850 (digital) Explore this journal Cite this article Simandl, G. J., Paradis, S. & Irvine, M. (2007). Brucite – Industrial Mineral with a Future. Geoscience Canada, 34(2), 57–64. All rights reserved © The Geological Association of Canada, 2007 This document is protected by copyright law. Use of the services of Érudit (including reproduction) is subject to its terms and conditions, which can be viewed online. https://apropos.erudit.org/en/users/policy-on-use/ This article is disseminated and preserved by Érudit. Érudit is a non-profit inter-university consortium of the Université de Montréal, Université Laval, and the Université du Québec à Montréal. Its mission is to promote and disseminate research. https://www.erudit.org/en/ GEOSCIENCE CANADA Volume 34 Number 2 June 2007 57 ARTICLE the topic for scientists studying the Table 1. The main raw materials used thermodynamic properties of brucite, in the production of magnesium metal. geologists studying its contact meta- Periclase is a natural form of man- morphic characteristics, exploration made magnesia (MgO). In most geo­ geologists and potential end-users. logical settings, periclase retrogrades to Given the demand for the mineral and brucite. metal, high-grade brucite deposits may become hot exploration targets within Chemical Mg Content Name Formula (wt %) the next few years. Brucite Mg(OH)2 41.7 SOMMAIRE Carnallite KMgCl3·6(H2O) 8.8 Brucite – Industrial Mineral La brucite, Mg(OH)2, est un minéral Dolomite CaMg(CO3)2 13.2 plutôt rare connu surtout des collec­ Forsterite Mg2SiO4 34.6 With A Future tionneurs de minéraux et des spécial­ Magnesite MgCO3 28.8 istes du métamorphisme de contact et Olivine (Mg,Fe)2SiO4 25.4 Periclase MgO 60.3 George J. Simandl1, Suzanne des roches ultramafiques. La brucite Serpentine Mg Si O (OH) 26.3 Paradis2 and Melanie Irvine1 est un matériau ignifuge écologique qui 3 2 5 4 1 est en demande commercialement; il British Columbia Ministry of Energy, Mines Mg(OH) . It has a higher magnesium représente aussi une source potentielle 2 and Petroleum Resources, PO 9333 STN content than any other raw material, de magnésium métallique, pour lequel PROV GOV’T, Victoria, BC, V8W commonly used or considered as ore existe une forte demande. La demande 9N3 Canada. Corresponding author (Table 1). Brucite forms soft, waxy to e-mail: [email protected] actuelle de brucite comme matériau glassy, white, pale-green, grey or blue ignifuge est de moins de 50 000 tonnes crystals, plate aggregates, rosettes, 2 Geological Survey of Canada, Sidney, annuellement, mais elle croît exponen- fibrous masses and fracture fillings. It Natural Resources Canada, 9860 West tiellement. La brucite a l'avantage de is relatively soft (2.5 on the Mohs Saanich Road, Sidney BC, V8L 4B2 ne pas contenir de CO2; et donc, aucun scale) and has a low density (2.38–2.40 3 Canada CO2 n'est produit lors de sa calcina­ g/cm ). It is soluble in hydrochloric tion, caractéristique très appréciée en acid but has no effervescence. Weath­ SUMMARY ces temps d'inquiétudes en regard des ering transforms waxy, fresh brucite Brucite, Mg(OH)2, is an uncommon changements climatiques. Notre article into a chalk-like material. mineral primarily known to mineral de synthèse présente un résumé de la Brucite is widely distributed in collectors, and to specialists studying question à l'intention des scientifiques ultramafic rocks (Khan et al. 1971; contact metamorphic and ultramafic intéressés par les propriétés thermody­ Hora 1998). It is also found in a variety rocks. It is an environmentally friendly namique de la brucite, aux géologues of exotic settings such as kimberlites flame-retardant and is in commercial intéressés par ses caractéristiques de (Malkov 1974) and carbonatites (Lee et demand; it also represents a potential minéral de métamorphisme de contact, al. 2000). Most of the economic ore source for the metal, magnesium, ainsi qu'aux géologues en général et brucite deposits appear to be hosted by which is itself in great demand. The aux utilisateurs. Étant donné la marbles affected by high-temperature, present brucite market for flame-retar- demande de brucite comme minéral et low-pressure metamorphism (mainly in dants is less than 50 000 tonnes annu­ comme source de métal, les bons gise­ pluton-associated, contact metamor- ally, but it is increasing exponentially. ments de brucite pourraient constituer phic aureoles). The fibrous variety of Brucite has the advantage of not con­ des cibles d'exploration dans un avenir brucite, nemalite, is common in ultra- taining CO2; hence none is released rapproché. mafic rocks, where it coexists with during calcination, a positive feature in chrysotile (Ross and Nolan 2003; Khan today’s society concerned with climate INTRODUCTION et al. 1971). Ultramafic-hosted deposits change. This review paper summarises Brucite is a magnesium hydroxide were considered as potential sources of 58 brucite in the past (Khan et al. 1971) Brucite occurrences have however, the world market for flame and are being considered again because recently been recognized in new geo­ retardant mineral fillers has been esti­ brucite fibres from the Shaan Nan logical settings, such as in accumula­ mated at 500 000 tonnes; magnesium Asbestos Mine in Shaan Xi Province, tions on the sea floor (Kelley et al. hydroxide accounts for approximately China, were tested as a reinforcing 2001a, b; Früh-Green et al. 2003), and 10% (Rothon 2004). The magnesium material for concrete (Liu et al. 2004). in the future brucite deposits belonging hydroxide estimate includes natural and The unfortunate association of brucite to this category may become of eco­ synthetic brucite. Natural brucite prob­ with asbestos in ultramafic settings, is nomic interest. ably accounts for less than 25 000 the main reason why carbonate-hosted tonnes in the field of flame-retardants. brucite deposits are the recommended BRUCITE USES Brucite is used also in waste- and preferred exploration targets. The The brucite market is relatively small, water treatment. For example, it has early negative studies on the inhalation but it is growing rapidly. Brucite is been proposed as one of the key min­ effects of brucite dust are invalid classified either as a magnesium metal erals in Britannia Mine’s (BC) effluent because the supposedly pure brucite ore or as an industrial mineral. In both treatment as a neutralizing reactant samples used in the experiments, con­ instances, it has to compete for its (Kus and Mavis 2001). Other uses tained up to 10% chrysotile (Davies et share of the market with other materi­ include agricultural feed, a dietary mag­ al. 1985). Liu et al. (2004) list a number als. According to the International nesium supplement, odour control, and of recent studies indicating that pure Magnesium Association, the primary in specialty cement preparations as an brucite is virtually harmless and this magnesium metal production for 2005 additive to Portland cements (Godfrey should allay some of the health con­ is estimated at 667 000 tonnes (Busi­ 2000). There is promising laboratory- cerns raised in earlier studies. ness Research Services Inc. 2006). scale research into the use of brucite in Examples of carbonate-hosted Many common rock-forming minerals stabilization of swelling clays (Xeidakis brucite deposits of economic signifi­ contain magnesium; however, brucite, 1996). Brucite readily reacts with CO2 cance are Cross Quarry near Wake- carnallite, dolomite and magnesite are during mineral carbonation tests to field, Québec, Canada (Jacob et al. the main ore minerals (Coope 2004). form magnesium carbonates; however, 1991; Hébert and Paré 1990; Perreault Hydrated chlorites other than carnallite brucite is not widely available (Chen et 2003); Kuldur, eastern Russia (Anony­ (such as bischofite), brines and seawa- al. 2006). mous 2005); Granåsen, Norway ter also represent important Mg Depending on the intended (Øvereng 2000); Gabbs magnesite– resources. In addition, serpentine industrial mineral use, natural brucite brucite deposit, Nye County, Nevada, (including asbestos tailings) and olivine competes for its share of the market USA (Schilling 1968) and Marble are possible raw materials. The extrac­ with synthetic brucite, commonly Canyon, Culberson County, Texas, tion of magnesium from silicates is referred to in the manufacturing indus­ USA (Newman and Hoffman 1996). technologically feasible but economi­ try by its chemical formula, magnesium Other undeveloped or cally challenging as was proven by the hydroxide, and with other minerals and exhausted brucite deposits occur in 2003 closure of Noranda’s Magnola compounds such as magnesite, China, Arizona, United Kingdom, Ire­ plant located in Québec. Elemental dolomite, huntite, hydromagnesite, land, North Korea and Canada; how­ magnesium (metal) and magnesium MgO, CaO, zeolites and others.
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