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. The ever, fundamental, publicly available compounds are produced from bit­ range of brucite’s price per tonne, in technical data are missing or not avail­ terns, seawater, and well and lake applications other than flame-retar- able. brines (Coope 2004). Table 1 shows dants, is not available. World brucite reserves and the magnesium content of the main resources are impossible to estimate raw materials used in magnesium metal CONTACT METAMORPHIC BRUCITE with any reasonable accuracy because production. DEPOSITS there are many inconsistencies in the As there are no large, high- Most of the brucite deposits of eco­ reported numbers. Kramer (2001) esti­ grade, developed brucite deposits in nomic interest are associated with shal­ mates brucite reserves for Nevada, production, natural brucite is not cur­ low-level igneous intrusions into MgO- USA, at 3 million tonnes and for rently used as raw material for magne­ bearing sedimentary or metasedimenta- North Korea at 2 million tonnes; how­ sium metal extraction. ry rocks. Examples of well document­ ever, there are no indications of their As an industrial mineral, ed, but not necessarily economic, grades. In Canada, under the 43-101CP brucite can be used in caustic and brucite occurrences hosted by contact Standards of Disclosure for mineral dead-burned magnesia production. It metamorphosed carbonates are projects, such tonnage estimates can­ also has a variety of other industrial described by Cartwright and Weaver not be referred to as reserves. Because mineral applications such as a func­ (1993), Ferry (1996a, b, 2000), Ferry the potential economic importance of tional filler in plastic compounds, fire and Rumble (1997) and Müller et al. brucite escaped the attention of most and smoke retardant (O’Driscoll 2005; (2004). In these and most other well- economic geologists, many carbonate- Hornsby 2001; Simandl et al. 2001), documented cases, the brucite-bearing hosted occurrences worthy of geologic electric wire insulation (Bisleri and zone is located closest to the igneous follow-up, such as those in British Fondeur 2001) and carpet backing. intrusion. Columbia (Simandl et al. 2006), were There are no reliable statistics for the Such studies are essential to never investigated in detail. brucite market in any of these fields; understand the stability of brucite- Volume 34 Number 2 June 2007 bearing assemblages and ultimately the genesis of brucite deposits. The chemi­ cal composition of the host rock and that of the ambient fluids, appropriate pressure and temperature conditions, duration of the thermal event, litholog- ical and structural controls, permeabili­ ty (infiltration rather than diffusion), direction of fluid flow and fluid/rock ratio (open system) are some of the parameters that determine if brucite is formed and the shape and grade of the deposit. Both dolomite and magnesite represent favourable host rocks for brucite formation (Fig. 1). The lower the mole fraction of carbon dioxide in the ambient fluid (X CO2), the lower the temperature required for brucite and periclase to be stable. The highest grade, nearly monomineralic brucite deposits are found in aureoles where the protolith consists of magnesite with little or no calcite, clays, chert or other mineral impurities. This is believed to be the Figure 1. Stability field of periclase and brucite in the CaO-MgO-CO2-H2O system case for the Kuldur deposit (Shevelev at 1 kbar. The shapes of the curves indicate that the stabilities of periclase and 2004) and probably for the deposits at brucite are strongly dependent on X (H2O) of the fluid (after von Trommsdorff Gabbs. In these situations, periclase and Schwander, 1969). Circled numbers refer to equations in the text. Abbrevia­ may have formed by dissociation of tions as follows: br-brucite, cc-calcite, dol-dolomite, p-periclase, m-magnesite. magnesite according to reaction (1):

(1) Magnesite = Periclase (MgO) + ure 1 appropriately represents the con­ ± magnesite cannot be expected. If the CO2 ditions of brucite formation. In such protolith is siliceous carbonate, then cases, periclase (MgO) is believed to calc-silicate minerals will be part of the Magnesite dissociation takes place dur­ have formed by a prograde, infiltra­ mineral paragenesis. Figure 2 illustrates ing the prograde metamorphic (or tion-driven reaction (3), referred to as the stability field of periclase, brucite metasomatic) phase. Later, periclase dolomite dissociation: and some of the other mineral assem­ may rehydrate to form brucite during blages that are expected at 1.5 kbar in the retrograde phase by the hydration (3) Dolomite = Periclase + Calcite + silicious dolomite, a geological setting reaction (2): CO2 that can be approximated by a CaO- MgO-SiO2-H2O-CO2 system. (2) Brucite = Periclase + H2O In most contact metamorphic settings, Contact metamorphic aureoles periclase does not survive the retro­ that overprint siliceous dolomite-bear­ Worldwide, sedimentary-hosted mag- grade metamorphism that follows a ing carbonates are divided into two nesite deposits such as those described metamorphic climax and it rehydrates categories: those aureoles that, at the by Simandl and Schultes (2004) repre­ to form brucite according to reaction peak of high-grade metamorphism, sent an ideal protolith for the forma­ (2). contained periclase-forsterite-calcite tion of high-grade brucite deposits, but In settings where mole frac­ and those that contained dolomite- they are uncommon. The settings tion of water (X H2O) is extremely forsterite-calcite (no periclase) assem­ where magnesite-rich rocks are affect­ high, brucite may form directly by blages. ed by contact metamorphism or meta­ reactions (4) and (5): If the prograde metamorphic somatism are, therefore, truly rare. peak assemblage is dolomite-forsterite- Dolostones have lower magnesium (4) Dolomite + H2O = Brucite + Cal- calcite, then brucite will form through content than magnesite-rich rocks so cite + CO2 reaction (6); however, during the retro­ they are less likely to host nearly grade stage forsterite may also react monomineralic brucite deposits. (5) Magnesite + H2O = Brucite + CO2 with calcite, H2O and CO2 to form Dolomitic rocks are present over rela­ tremolite and dolomite or serpentine tively wide areas in most geological set­ In most geological settings, almost and dolomite (Ferry 2000). tings. If the dolomite is pure, then Fig- pure carbonate consisting of dolomite 60

(11) Tremolite + 11 Dolomite 8 Forsterite + 13 Calcite H2O 9 CO

(12) 3 Dolomite + Diopside = 2 Forsterite + 4 Calcite + 2 CO2 (13) 0.21 Tremolite + 0.064 Calcite + 0.15 CO2 ! 0.105 Dolomite + 0.02 gb H2O + 0.171 SiO2 (metastable)

(14) Tremolite + 3 Calcite = 4 Diop- side + Dolomite + H2O + CO2

SELECTED EXAMPLES OF FAVOURABLE GEOLOGICAL SET­ TINGS FOR BRUCITE EXPLORATION In most localities, where brucite occurs within impure dolomitic rocks (CaO- MgO-SiO2-H2O-CO2 system) in a con­ tact metamorphic environment, the Figure 2. Stability field of periclase and brucite in the CaO-MgO-SiO -CO -H O 2 2 2 reactions shown in Figure 2 apply. system at 1.5 kbar. The shapes of the curves are identical to Figure 1; however, this With increasing temperature and figure also provides information regarding the stability of a number of calc-silicate minerals. Circled numbers refer to reaction equations in text. br-brucite, per-peri- decreasing distance to the intrusive clase, qtz-quartz, tlc-talc, tr-tremolite, cc-calcite, dol-dolomite, di-diopside, fo- contact, there is a successive appear­ forsterite. Reaction 13 is metastable (after Müller et al. 2004). ance of talc, tremolite, forsterite and periclase and/or brucite. This pattern (6) 34 Forsterite + 51 H2O = Serpen- brucite rather than the formation of has been found in several well- tine 20 Brucite serpentine or any other magnesium sili­ described localities. The Ubehebe Peak cate. In many such cases, textural evi­ contact aureole, in California, USA As with most industrial minerals and dence suggests that periclase that (Fig. 3), is an excellent example show­ metal ores, grade is one of the most formed during peak metamorphism ing the first appearance of index min­ important economic parameters. was subsequently converted to brucite; erals tremolite, forsterite and periclase Therefore, exploration geologists however, this is probably not universal, retrograded to brucite; at this locality should concentrate their efforts on and is not applicable to all brucite talc was not reported. The absence of geological settings with favourable bulk occurrences or deposits because the diopside zone at this site was inter­ chemical composition where, X (CO2) brucite may also form by reactions 5 preted by Müller et al. (2004) as a may have approached zero (i.e. an and 6. result of fluid infiltration. A similar open system rich in meteoric or mag- Brucite may be destabilized in pattern is observed at the Beinn an matic fluids), temperature exceeded surface environments (regolith or out­ Dubhaich aureole, northwest Scotland 600ºC and where permeability was crop) and converted to hydromagnesite (Fig. 4; Holmes 1992; Ferry and Rum­ high during the peak conditions of and atinite (Schilling 1968). ble 1997), but at this locality, talc was contact metamorphism. Such settings The reactions explaining the noted. Mineral zonations, together with coincide with the highest metamorphic sequence in which talc, tremolite, diop- the position of the heat source grade of metamorphic aureoles (near side and forsterite appear in typical (igneous body) may be used in the intrusive-carbonate contacts and along contact metamorphic environments, exploration for brucite deposits to nearby fault and fracture zones), where (Fig. 2), are listed below. focus on favourable environments. the hydrothermal fluid travels quickly Brucite-bearing zones depicted by Fig­ without cooling down because of its (7) 3 Dolomite + 4 Quartz + 1 H O ures 3 and 4 are not known to contain reactions with the host rock. 2 = 1 Talc + 3 Calcite + 3 CO2 economic brucite deposits; however, It is essential that ambient flu­ both show the either partial or com­ ids retain high X (H2O), low X (CO2) (8) 5 Talc + 6 Calcite 4 Quartz = plete metamorphic sequence of talc, and the rocks remain calcite deficient 3 Tremolite 6 CO2 +2 H2O tremolite, forsterite and periclase (com­ for the optimum preservation of monly retrograded to brucite). brucite; otherwise, destabilization of (9) 5 Dolomite + 8 Quartz 1 H2O Depending on the chemical composi­ brucite will occur by reaction with cal- = 1 Tremolite + 3 Calcite + 7 CO2 tion of the protolith, hydrothermal flu­ cite to form retrograde dolomite as ids and pressure/temperature condi­ shown in reaction (4). (10) Dolomite + 2 Quartz = Diopside tions, other minerals, such as wollas- Low silica activity in the ambi­ + CO tonite, may be present (Fig. 3). ent fluid also favours precipitation of Figure 5 shows the extent of GEOSCIENCE CANADA Volume 34 Number 2 June 2007 61

Figure 3. Mineral zoning within contact metamorphic aureole can be used to focus exploration efforts. In this example from Ubehebe Peak, Death Valley National Park, California, USA, the first appearance of tremolite (Tr), forsterite (Fo), and periclase (Per) indicates increasing temperature. Periclase formed in the hottest part of the contact zone, but was replaced by brucite. The appearance of wollastonite (Wo) may indicate local variation in the composition of the protolith. Pognip Lime- Figure 5. Geological setting of the stone(Op), Eureka Quartzite (Oeq), Ely Springs Dolomite (Oes), Hidden Valley Marble Canyon Mine, Texas, USA. Dolomite (DShv), Lost Burro Formation (Dib), Perdido Formation (Mp), Tin The zoned pluton consists of granite, Mountain Limestone (Mtm), alluvium (Qal), Paleozoic rocks (PAL) (from Roselle syenodiorite and syenogabbro. The et al. 1999). brucite-in line shows good continuity but variable width of the brucite-bear- ing zone (after Newman and Hoffman (1996).

Figure 4. Geology of the southeastern part of the Beinn an Dubhaich aure­ ole, Isle of Skye, northwestern Scot­ land (after Holmes 1992; Ferry and Rumble 1997). The first appearance of index minerals such as talc, tremolite and forsterite can be used to zero in on potentially economic brucite deposits. 62 the favourable brucite-bearing zone in first appearances of tremolite, forsterite the Marble Canyon area of Texas, with periclase and/or brucite directly which developed in dolomitic rocks in contact with the intrusive rock (Fig. that surrounded an elliptically shaped 4). Also, exploration should not be intrusive complex, consisting of horn­ limited to areas surrounding the plu- blende-bearing granite, syenodiorite ton, as suggested by Figures 3, 4 and 5 and syenogabbro (Newman and Hoff­ because the roof pendants caught with­ man 1996). The brucite occurs within in the plutonic rocks offer ideal condi­ dolomitic rocks of the Hueco and tions for brucite formation as well. Bone Springs formations (Fig. 5). The There is also the possibility brucite-bearing halo surrounding the that the potential for formation of an zoned intrusive body is up to 150 m economic brucite deposit increases Figure 6. Brucite-bearing carbonate wide. The protolith of the Hueco For­ when the marbles are in contact with boulder characterized by mottled tex­ mation is less siliceous than that of the silica-undersaturated rocks, such as ture caused by white, porous, soft Bone Springs Formation; consequently, syeno-gabbros (Fig. 5), or when the patches consisting of weathered it contains fewer calc-silicate minerals intrusive rock is a syenite, such as at brucite. The less weathered grey and has a better potential to host eco­ the Stephen Cross Quarry in Québec. matrix consists of calcite. nomic brucite deposits (Newman and Due to its visible and near Hoffman 1996). Applied Chemical infrared spectra properties, remote Magnesias Corp. markets the brucite- sensing methods could identify brucite- bearing marble mined from this zone. rich rocks (Kozak and Duke 1999). The recessive nature of brucite SUMMARY AND GUIDELINES FOR deposits makes boulder tracing one of MINERAL EXPLORATION AND the most effective prospecting meth­ DEVELOPMENT ods. Brucite-bearing carbonate boul­ Brucite currently has a relatively small ders are mostly pale (white or grey), are market (Simandl et al. 2006), largely characterized by mottled texture and due to the rarity of high-grade deposits have porous soft patches within the in comparison to other more common carbonate matrix (Figs. 6 and 7). magnesium-bearing minerals, such as Depending on the degree of weather­ dolomite and magnesite. Large, high- ing and ore grade, brucite can be Figure 7. Photomicrograph of brucite grade brucite deposits could be a altered to hydromagnesite or atinite for (br) aggregates in carbonate matrix source of material for a variety of depths down to, or greater than, five (brown). Matrix consists predominant­ industrial mineral applications, such as metres. If brucite is formed within a ly of calcite (ca). Field of view approx­ manufacturing of caustic or dead- dolomite rather than a magnesite pro- imately 2.5 mm, plane light. burned magnesia or for the production tolith, the deposit is expected to have a of magnesium metal. One of the most lower grade and the alteration is not spectacular brucite specimen at the important advantages of brucite over expected to be as deep. Kennedy Lake Mine and also provided magnesium-bearing carbonates is that most of the project-related photo­ it does not contain CO2 that would be CONCLUSION graphic documentation. Brian Grant released during calcination or process­ Brucite is an industrial mineral with an and David Lefebure from the British ing. It is conceivable that the future excellent market-growth potential; it is Columbia Ministry of Energy, Mines use of brucite may involve CO2 credits. currently used in a variety of niche and Petroleum Resources helped to Brucite would be an excellent candi­ markets such as fillers, flame retardant improve earlier versions of this manu­ date for mineral sequestration if it were and in environment rehabilitation. The script. Léopold Nadeau of the Geolog­ available on a large scale at a low to main reason why brucite is not used ical Survey of Canada in Quebec City moderate price. more widely is due to the rarity of proof-read the final version. Although brucite is relatively large, high-grade deposits. Worldwide, widespread as an accessory mineral in a there are several brucite occurrences REFERENCES variety of rock types, Mg-rich carbon­ similar to those reported in British Anonymous, 2005, The brucite of Kuldur ate horizons within contact metamor- Columbia (Simandl et al. 2006), where deposit: Russian Mining Chemical Company. Online at: phic aureoles have the best exploration the extent of the brucite-bearing zone [http://www.brucite.ru/eng/] potential. Dolostone or magnesite- and brucite content is unknown. Such Bisleri, C., and Fondeur, J.H., 2001, Fire- bearing rocks are the most favourable occurrences merit detailed follow-up resistant and water-resistant halogen- protoliths because they provide in situ exploration using guidelines highlight­ free low-voltage cables, patent sources of magnesia. In normal contact ed here. EP1128397: Online at: aureoles, exploration geologists should [http://v3.espacenet.com] expect the following (or similar ACKNOWLEDGEMENTS Business Research Services Inc., 2006, sequence): unaffected carbonate rock, Laura Simandl, from St. Margaret’s Years 2000-2005. Primary Magnesium first appearance of talc followed by School in Victoria, collected the most Production: Online at: GEOSCIENCE CANADA Volume 34 Number 2 June 2007 63

[http://www.intlmag.org/files/yend20 fluid infiltration of the calc-silicate magmas represented in the system 05.pdf] aureole of the Beinn an Dubhaich CaO-MgO-CO2-H2O at 0.2 GPa: Cartwright, I., and Weaver, T.R., 1993, granite, Skye: Journal of Petrology, v. Mineralogy and Petrology, v. 68, p. Fluid-rock interaction between syen­ 33, p.1261-1293. 225-256. ites and marbles at Stephen Cross Hora, Z.D., 1998, Ultramafic-hosted Liu, K., Cheng, H., and Zhow, J., 2004, Quarry, Québec, Canada: petrological Chryssotile Asbestos, in Geological Investigation of brucite-fiber-rein- and stable isotope data: Contributions Fieldwork 1997: British Columbia forced concrete: Cement and Concrete to Mineralogy and Petrology, v. 113, Ministry of Employment and Invest­ Research, v. 34, p.1981-1986. no. 4, p. 533-544. ment, Paper 1998-1, p. 24K-1- 24K-4. Malkov, B.A., 1974, Brucite in kimberlite: Chen, Z.Y., O’Connor, W., and Gerde- Hornsby, P.R., 2001, Fire retardant fillers Transactions (Doklady) of U.S.S.R mann, S.J., 2006, Chemistry of aque­ for polymers: International Materials Academy of Science, Earth Science ous mineral carbonation for carbon Reviews, v. 46, no.4, p. 199-210. Section, v. 215, p. 157-160. sequestration and explanation of Jacob, H.-L., Cotnoir, D., Depatie, J., Gof- Müller, T., Baumgartner, L.P., Foster, Jr., experimental results: Environmental faux, D., Dans, D., and Bergeron, M., C.T., and Vennemann, T.W., 2004, Progress, v. 25, no. 2, p. 161-166. 1991, Les Mineraux Industriel du Metastable prograde mineral reactions Coope, B., 2004, Magnesium metal – Quebec cours intensif no.3: Associa­ in contact aureoles: Geology, v. 32, sources, processes and markets, in tion Professionelle des Geologues et no. 9, p. 821-824. Simandl, G.J., McMillan, W.J. and Geophysiciens du Québec. Newman, T.E., and Hoffman, G.K., 1996, Robinson, N.D., eds., Proceedings of Kelley, D.S., Karson, J.A., Blackman, D.K., Brucite deposit in Marble Canyon, the 37th Forum on the Geology of Früh-Green, G.L., Butterfield, D.A., Culberson County, Texas, in Austin, Industrial Minerals, May 23-25, 2001, Lilley, M.D., Olson, E.J., Schrenk, G.S., Hoffman, G.K., Barker, J.M., Victoria, BC, Canada: British Colum­ M.O., Roe, K.K., Lebon, G.T., and Zidek, J. and Gilson, N., eds., Proceed- st bia Ministry of Energy and Mines, Rivizzigno, P, 2001a, An off axis ings, 31 Forum on the Geology of Paper 2004-2, p. 1-56. hydrothermal vent field discovered Industrial Minerals: New Mexico Davis, J.M.G., Addison, J., Bolton, R.E., near the Mid-Atlantic Ridge at 30°N: Bureau of Mines and Natural Donaldson, K., Jones, A.D., and Nature, v. 412 (6843), p. 150–157. Resources, Bulletin 154, p. 37-42. Miller, B.D., 1985, Inhalation studies Kelley, D. S., Karson, J., Blackman, D., O’Driscoll, M., 2005, Magnesia minors – on the effects of tremolite and brucite Früh-Green, G., Butterfield, D., Lilley, brucite, huntite and hydromagnesite: dust in rats: Carcinogenesis, v. 6, no. M., Schrenk, M., Olson, E., Roe, K., Industrial Minerals, No. 453, Metal 5, p. 667-674. and Lebon, J., Applegate, B., Bacher, Bulletin Plc., p. 41-47. Ferry, J.M., 1996a, Three novel isograds in N., Cann, J., Gee, J., Hanna, H., Øvereng, O., 2000, Granåsen, a dolomite- metamorphosed siliceous dolomites Hurst, S., John, J., Lyons, S., Morgan, brucite deposit with potential for from the Ballachulish aureole: Ameri­ J., Nooner, S., Ross, K., Sasagawa, G., industrial development: Norges Geol- can Mineralogist, v. 81, p. 485-494. and Schroeder, T., 2001b, Discovery ogiske Undersøkelse, Bulletin 436, p. Ferry, J.M., 1996b, Prograde and retro­ of Lost City: An off-axis peridotite- 75-84. grade fluid flow during contact meta- hosted, hydrothermal field near 30°N Perrault, S., 2003, The ups and downs of morphism of siliceous carbonate rocks on the Mid-Atlantic Ridge: Newsletter industrial mineral production in from the Ballachulish aureole, Scot­ of the US RIDGE Initiative, v. 11, Québec: a response to changing mar­ land: Contribution to Mineralogy and no. 2, p. 3-9. kets: Newsletter of the Mineralogical Petrology, v. 124, p. 235-254. Khan, S.A., Ali, K., and Alam, S. J., 1971, Association of Canada, No. 71, p. 1- Ferry, J.M., 2000, Patterns of mineral Brucite deposits of Hindubagh (West 23. occurrences in metamorphic rocks: Pakistan): Pakistan Journal of Scientif­ Roselle, G.T., Baumgartner, L.P., and Val­ American Mineralogist, v. 85, p. 1573- ic and Industrial Research, v. 14, no. ley, J.W., 1999, Stable isotope evi­ 1588. 6, p. 542-545. dence of heterogeneous fluid infiltra­ Ferry, J.M. and Rumble, D., 1997, Forma­ Kozak, P.K., and Duke, E.F., 1999, Visible tion at Ubehebe Peak, California: tion and destruction of periclase by and near infrared spectra of contact American Journal of Science, v. 299, fluid flow in two contact aureoles: metamorphosed calcareous rocks: p. 93-138. Contributions to Mineralogy and implications for mapping metamor- Ross, M., and Nolan, R.P., 2003, History Petrology, v. 128, p. 313-334. phic isograds by hyper spectral remote of asbestos discovery and use and Früh-Green, G.L., Kelley, D.S., sensing methods: The Thirteenth asbestos-related disease in context Bernasconi, S.M., Karson, J.A., Lud- International Conference on Applied with the occurrence of asbestos within wig, K.A., Butterfield, D.A., Boschi, Geological Remote Sensing, p. I-363- ophiolite complexes: Geological Soci­ C., and Proskurowski, G., 2003, I-370. ety of America, Special Paper 273, p. 30,000 years of hydrothermal activity Kramer, D.A., 2001, Magnesium, its Alloys 447-470. at the Lost City Vent Field: Science, v. and Compounds: US Geological Sur­ Rothon, R., 2004, European flame retar­ 301, p. 495-498. vey, Open-File Report 01-341, 29 p. dants: Industrial Minerals, No. 437, Godfrey, P.J., 2000, Magnesium Cement Kus, J., and Mavis, J., 2001, Britannia miti­ Metal Bulletin Plc., p. 35-39. Project Independent Appraisal: gation program – interim treatment, Schilling, J.H., 1968, The Gabbs magne- TecEco Pty Ltd., 23 p. Britannia Mine Remediation Project, site-brucite deposit, Nye County, Hébert, Y., and Paré, C., 1990, Les Corporate Land and Resource Gover­ Nevada, in Ridge, J.D., ed., Ore ressources en minéraux de magnesium nance: Ministry of Sustainable Deposits of the United States, 1933- et leur utilisation au Québec: Ministère Resource Management, 2 p. 1967: Graton-Sales, American Insti­ de l’Énergie et des Ressources du Lee, W.-J., Fanelli, M.F., Cava, N., and tute of Mining, Metallurgical and Québec, MB 90-31. Wyllie, P.J., 2000, Calciocarbonatite Petroleum Engineers, New York, v. 2, Holmes, M.B., 1992, Metamorphism and and magnesiocarbonatite rocks and p. 1608-1621. 64

Shevelev, A. I., 2004, Magnesite deposits of Russia: 32nd International Geologi­ cal Congress, Florence, Italy, DWO 14-16. GEOLOGICAL Simandl, G.J., and Schultes, H., 2004, Clas­ sification of magnesite deposits with ASSOCIATION OF emphasis on the Mount Brussilof and Kunwara types, in Simandl, G.J., CANADA McMillan, W.J. and Robinson, N.D., eds., Proceedings of the 37th Forum on (2007-2008) the Geology of Industrial Minerals, May 23-25, 2001, Victoria, BC, Cana­ da: British Columbia Ministry of Ener­ OFFICERS gy and Mines, Paper 2004-2, p. 83-85. President Simandl, G. J., Simandl, J., and Debreceni, Carolyn (‘Lyn) Anglin A., 2001, Hydromagnesite-magnesite resources: potential flame retardant Vice-President material: British Columbia Ministry of Carolyn Relf Energy and Mines, Geological Field- Past President work 2000, p. 327-336 Robert Marquis Simandl, G. J., Paradis, S., Robinson, N. D, Simandl, L., and Irvine, M.L., 2006, Secretary-Treasurer Brucite in British Columbia: British Roger Mason Columbia Ministry of Energy and Mines and Petroleum Resources, COUNCILLORS Geofile 2006-3. von Trommsdorff, V., and Schwander, H., Carolyn (‘Lyn) Anglin 1969, Brucitmarmore in den Bergeller- Kevin Ansdell alpen: Bulletin Suisse de Mineralogie Penny Colton et Petrographie, v. 49, no. 2, p. 333- Peter Dimmell 340. Greg Finn Xeidakis, G.S., 1996, Stabilization of John Gosse swelling clays by Mg (OH)2. Changes in clay properties after addition of Jeff Harris Mg-hydroxide: Engineering Geology, John Ketchum v. 44, p. 107-120. Garth Kirkham Alain Liard Michel Malo Robert Marquis Roger Mason Jeff Packard Steve Piercey Carolyn Relf Jim Teller Eileen van der Flier-Keller

STANDING COMMITTEES Communications: John Gosse Finance: Michel Malo Publications: Jeff Harris Science Program: Greg Finn