Please note that this is an author-produced PDF of an article accepted for publication following peer review. The definitive publisher-authenticated version is available on the publisher Web site komatiite whereas +1.06‰, and +0.14 between ranging values positive showed (SDO shale P1), A1; (Nod nodules two-stage Manga +0.05‰. of composition BSE average an suggesting a +0.16‰, and −0.13 between values through (2 purification 0.05‰ NIST was for 986 SRM precision measurement intermediate and After 0.04‰, and 0.02 between was isotope mean) the deposits. of error Ni mass-dependent ore of standard (two precision for Measurement method. correction and double-spike corrected a using bias range mass instrumental were and MC-ICP-MS the by measured rocks were report ratios isotope Ni to procedure, magmatic chromatography (d) and in 986 fractionations isotope SRM Ni the NIST to relative Earth material Silicate Bulk reference the of composition isotope the assess to (c) reference materials, geological various of composition isotope Ni the determine to (b) determination, isotope Ni and rocks, sedimentary and for procedure analytical an todetail (a) fourfold: is igneous contribution Our poorly known. remains ore deposits terrestrial of composition isotope Ni the biosignature, potential a as and cosmochemistry for isotopes Ni of applicability the demonstrated have studies initial Although Abstract Bleuenn Gueguen, : *: Corresponding author 3 2 1 Thedefinitive version isavailable at ©2013 Research InternationalGeoanalysts of Association © http://dx.doi.org 297 pages 37, 3, Issue Volume 2013, September Research Geoanalytical and Geostandards tnad stpqe e ééec d nce NS SM 8, t d rpre l gme des gamme la reporter (d) et 986, SRM NIST au nickel rapport par de (BSE) Globale référence Silicatée de Terre la isotopique de isotopique standard composition la estimer (c) variés, contribution Notre connue. référence de géologiques matériaux peu de isotopique composition la déterminer (b) nickel, en isotopiques très encore est minerais de compositions des détermination la pour analytique procédure la détailler (a) axes, quatre en s'organise dépôts des celle que ainsi terrestres sédimentaires et ignées roches des nickel du isotopique composition la biologique, signature que tant en et cosmochimie en nickel du isotopes des pertinence la démontrent études premières les que Bien Résumé : abiotic fractionation : Keywords −0.10 −1.03‰. to varied from Department of Geological Departmentof Sciences, Manitoba, University of Canada Winnipeg, GéosciencesIFREMER, Brest, Plouzané, Marines, de Unité France Centre Mer, de la Université BretagneInstitut UniversitaireEuropéen UMRde Occidentale, 6538, France Plouzané,

2013 The Authors.Geostandards 2013 and Geoana Nickel Isotope Variations in Terrestrial Silicate Rocks and Geological Geological and Rocks Silicate Terrestrial in Variations Nickel Isotope Bleuenn Gueguen Bleuenn :

nickel ; stable isotopes ; isotopes ; stable nickel / 10.1111/j.1751 MS by MC-ICP- Measured Materials Reference 1,2,* s Rouxel Olivier , ). Igneous- and mantle-derived rocks displayed a restricted range of of range restricted a displayed rocks mantle-derived and Igneous- ). - 908X.2013.00209.x http://onlinelibrary.wiley.com/

- 1), coal (CLB coal 1), MC 1,2 [email protected] -ICP- , Emmanuel Ponzevera Emmanuel , lytical lytical

MS

– - ; geological reference materials ; Bulk Silicate Earth; Earth; Silicate Bulk ; materials geological reference ; 1) and a metal a and 1) 317

- 2 contaminated soil (NIST SRM 2711) 2711) SRM (NIST soil contaminated , Andrey Bekker , Andrey

http://archimer - hosted Ni hosted 3

, Yves Fouquet , Yves Archimer - rich sulfides sulfides rich .ifremer.fr δ 60/58 nese nese 2

Ni Ni 1

Please note that this is an author-produced PDF of an article accepted for publication following peer review. The definitive publisher-authenticated version is available on the publisher Web site is, that isotopes, occurring naturally five has Nickel abiotique ; fractionnement Globale Silicatée Mots- −1.03‰. −0.10 à de allant négatives δ valeurs valeurs des ont des komatiites les dans présents nickel en riches donnent sulfures les que tandis +1.06‰, et +0.14 271) SRM (NIST métaux en contaminé sol le et (CLB-1) charbon le (SDO-1), shale le P1), A1; (Nod manganèse de nodules Les +0.05‰. à BSE de restreinte gamme une δ la montrent isotopiques mantelliques valeurs NIST de et le ignées pour roches standard Les intermédiaire (erreur (2s). mesure 0.05‰ de de mesures est précision 986 la nos SRM et de 0.04‰, masse et fidélité de 0.02 entre La biais comprise du est double-spike. moyenne) corrigés du puis méthode MC-ICP-MS la par par mesurés instrumental été ont nickel du isotopiques rapports les étapes, deux en chromatographie de les procédure une suivant purification et Après minerais. de magmatiques dépôts roches les dans masse la de dépendants nickel du isotopiques fractionnements significant Ni isotope fractionation in magmatic sulfides, and only two studies subsequently report Ni Ni report crustal of composition isotope subsequently studies two demonstrates only (2006) and sulfides, Hirata magmatic in and fractionation Tanimizu isotope Ni by significant study initial as An such systems. isotope behind processes non-traditional lags reservoirs other terrestrial abiotic of systematics isotope or Ni of understanding However, the micro-organisms, crystallisation. potential, mineral its despite by during or Ni systems, aqueous in of adsorption or assimilation precipitation chemical as Rouxel and such Anbar processes, 2004, Beard biotic and either of Albarede result the be should (e.g., environments natural in Cu fractionation observed any and that implies It Cr 2007). Mo, Fe, as such metals transition mass- induce not will processes controlled 1983, Lugmair of and decay (Rugel rapid the Shimamura from resulting meteorites 1983, iron in Allegre anomaly Moynier and 2006, Hirata Morand and (e.g., Tanimizu processes cosmochemical to mainly applied been have studies isotope Ni date, To respectively. 0.9%, and 3.6% 1.1%, 26%, 68%, clés et

al : . 2009). As Ni occurs solely in one natural valence state (Ni state valence natural one in solely occurs Ni As 2009). . nickel ; isotopes stables ; MC-ICP-MS ; matériaux géologiques de référence ; Terre Terre ; référence de géologiques matériaux ; MC-ICP-MS ; stables isotopes ; nickel 60/58 Ni entre −0.13 et +0.16‰, ce qui suggère une composition moyenne de la la de moyenne composition une suggère qui ce +0.16‰, et −0.13 entre Ni et

al . 2007, Cook Cook 2007, . depende t stpc rcintos s s h cs o other for case the is as fractionations isotopic nt 58 Ni, et 60 Ni, Ni,

al . 2008), specifically to detect any any detect to specifically 2008), . 61 60 Ni, Ni, Fe, which has a half-life of 2.62 Myr Myr 2.62 of half-life a has which Fe, 62 60/58 Ni and Ni 2+ i oiie cmrss entre comprises positives Ni ) in the Earth's crust, redox- crust, Earth's the in ) 64 Ni, with abundances of of abundances with Ni, 60 Ni 2

terrestrial analyses based rocks, ofmantle-derived on rocks and komatiites. composition oftheBulk SilicateEarthnecessary o ofrocktypes range alarge in detectable with thepurpose laboratories and Ni isotopecompositionforRMstoallowacomp forinstrumental method tocorrect pl coupled collector-inductively isotopic determination ingeological samples, includingsediments igneous and rocks by multi- Ni high-precision protocol toperform analytical and experimental this studyat (1)developing an growingNi isot of studiesapplySince a number with methanogens(Cameron values, and encompassesthe magnitude fractio of Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards dolerite sampled inNort DNC-1,a Iceland; from BHVO namely materials, reference geological Sample description Materials andmethods ligands,as Ni such among indicatethatfractionation Ni results Theexperimental andhydroxides). carbonates among abiotic Niisotopefractionations aqueous uncertain. More recently, Fujii Identification biosignatures in 2009). ofsuch 60 methan producing methanogens –micro-organisms etal rocks (Cameron

Accepted ArticleNi/ 58 Ni ratiosby1.5‰ byinco uptopreferential Geological reference materials: materials: reference Geological 2+ , NiSO . 2009,Gall 4 , NiCO et al et al asma-mass spectrometry (MC-ICP-MS) and using adouble-spike (MC-ICP-MS) and asma-mass spectrometry et al . 2009). . 2009). of demonstrating thatsignifiof demonstrating massbias,(2)providing asubsta . (2011) report theoreticala . (2011)report 3 , NiHCO . 2012). Interestingly, studydemonstratedthat recent . 2012). a Samples analysed inthisstudy include several USGS ccurring on Earth, and (3) assessing Ni isotopic assessing onEarth,and(3) ccurring 3 complex naturalsystem complex + -2, a basalt-2, fromHawaii , NiCl ope systematics tonaturalsamples, we aimed for interpreting Niisotopefractionation in h Carolina (USA);DTS-1,a dunite sample from species (i.e., chlorides, sulfides, sulfates, sulfates, sulfides, chlorides, (i.e., species arison of Ni isotope data among different ofNiisotopedataamong different arison nation during biological processes associated during associated nation biologicalprocesses rporation of the light isotope(Cameron rporation ofthelight e in anaerobic environments –fractionate environments e inanaerobic + andNiOH cant Ni isotope variations are variationsare cant Niisotope nd experimental constraintson experimental nd + isupto 2.5‰in ntial and releva ntial and s, however, remains s, however, (USA); BIR-1,a basalt (USA); nt dataset of nt dataset δ 60/58 Ni et al . Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards crystallisation. and poten Earth (BSE)Niisotopecomposition this selected set and ofigneous mantle-derived allowed rocks the estimation ofthe Bulk Silicate al during Japan) Eastern (hole C,PacificOcean, thefirstfewmetres in stratigraphic sequence, addition, samplesofa between olivineglass, andwhilstserpentinite by hand-picking separated were Deep basalts FeMO glass ofthe andfresh Olivine analysed. also were (Ifremer-Genavir) Atalante by R/V the etal hydrothermal field(Rouxel Washington). Samples ofserpentinised ultramafic FeMO the during recovered were These samples site the from were selected pillow lavaflows recentolivine-phyric from fromseafloorglass basalts andolivine volcanic analysed. Formation geological material reference pr element and major study oftrace etal Mn-nodule RMs,Axelsson For Govindaraju (1994). oftheseRMsand USA). Furtherdescription NISTalso analysed SRM2711,amodernsoilRM collected and thegraniteG-2 (USA); Kentucky Morehead, from shale aDevonian in theCastlemanCoalfield,Maryland, USA);SDO-1, depth)Lowercoal oceans, bedBakerstown (Bettinger respectively; a fromthe Mine CLB-1, coal theAtlan from manganese nodules No (USA); State Washington the areain Sisters the Twin Sisters area Washington inthe PCC-1,a state peridotite (USA); sample fromthe Twin

Accepted etal . 2000,Rouxel Article Selected samples ofbasalts, mantle-derived andmarine rocks sediments: Fresh . 2003) w alsostudied.Together were ltered and fresh basalts, and deep-sea clays (from the top ofthe (from the clays deep-sea basalts,and andfresh ltered FeMO Deep . 2004,Fouquet concentrations. In addition,the concentrations. tic (Blake Plateau at 788 m depth) and Pacific (at 4300m (at at788mdepth)andPacific Plateau tic (Blake at the base of Loihi Seamount (Edwards Loihi Seamount(Edwards of at thebase ovided by the CRPG (Nancy, France) was also was also France) (Nancy, by CRPG the ovided their chemical composition can befoundin chemical compositioncan their to evaluate potential Ni powders were prepared from bulk rocks. Inbulk rocks. from prepared powders were below the seafloor) recovered at IODP at site1149 recovered theseafloor) below cruise 185 by the R/V Joides Resolution (Plank 185byR/VJoides cruise the tial Ni isotope fractionationduring olivine d-A-1 and Nod-P-1 repr andNod-P-1 d-A-1 in the Sullivan quarry (Rhode Island, USA).We in theSullivanquarry (Rhode et al et cruise by the R/V Thompson (University of byR/VThompson(University cruise the rocks that were recovered from the Logatchev fromthe recovered rocks thatwere affected by metal contamination (Montana, metalcontamination by affected . 2010) during the MICROSMOKE cruise . 2010)during theMICROSMOKE . (2002)providean ith volcanic rocks available as RMs, asRMs, available rocks volcanic ith ca . 3.8 IF-GGa BandedIron isotope fractionation isotopefractionation esenting composites of intercomparison et al . 2011). et et Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards withhot8moll washed were Teflon beakers in Western Australiathe andAbitibigreenstone beltinCanada (Bekker belt greenstone Agnew-Wiluna the areas: two from analysed oreswere sulfide Ni-rich associated Acceptedmol l withcold1.2 cleaned was acids. Allplasticware France apparatus (Analab, fromreag double-distilled and columnworkwere (Milli-Q grade) Bothwas used. concentrated nitricand hydrochloricfordissolution acids used Experimental procedure isotopecompositions(Moynierpreviously Ni determined and content Ni high very their because of procedure and analytical experimental the testing analysed. was also in massive andblebbysulfides; ArticleMuir andComba1979,Houlé a kom mineralisation occursin the Abitibigreenstone beltinCanada mine,Alexo are wherefrom the sulfide Fe-Ni-Cu-PGE greenstone are belt among the largest komatiite-hosted Ni-Cu-PGEore deposits.Samples from grains.TheMountKeith pentlandite andpyrrhotite mostly comprising aggregates orsulfide ores sulfide massive sulfides, occurs asdisseminated komatiites withcumulates, thinspinifex-textured units and komatiitic basalts. Mineralisation volcanogenic massive sulfidic sulfides, cherts sequencewith felsicmafic and toultramaficcomp beltiscomposed greenstone Ga Agnew-Wiluna Komatiite-hosted Ni-rich sulfides: Reagents and materials: Reagents andmaterials: meteorites: Iron Two iron meteorites,na Two iron ). Acids of lower molarity were prepared from these double-distilled fromthese were prepared molarity ). Acidsoflower et al atiitic unitwitholivine cumu addition, brownolivineassociated Ultra-pure 18.2M Ultra-pure . 2012). Nickel-rich sulfideoresse . 2012).Nickel-rich Bulk rock samples comprising bothkomatiites and -1 , carbonaceous shales, and laterally variable variable andlaterally shales, carbonaceous , HNO of a deep-marine volcanic and volcaniclastic volcanic adeep-marine of mely Gibeon and Nantan, were selected for for selected were andNantan, Gibeon mely ent-grade acids using a Cleanacids® distillation aCleanacids® acidsusing ent-grade ositions, whichlocally cont and Perseverance sites of the Agnew-Wiluna of theAgnew-Wiluna sites andPerseverance Ω 3 (reagent grade). grade). (reagent cm water witha cm made Millipore system -1 HCl(reagentgrade), whereas Savillex® et al lates (Naldrett and Mason1968, lates (Naldrett . 2007,Cook withdisseminatedNi-sulfides lected forthisstudylected include et al et et al . 2009).The ains largelensesof . 2008). ca . 2.7 and 6moll HCl, while silicatewere witha rocksmixture digested of2mlconcentrated(28moll HF Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted dissolution. chemical to digestion orga at600°Ctooxidise nicmatterbefore ashed prior were coal CLB-1 SDO-1andthe solution madeby thattheshale SCPScience).Note onepuremono-elementa and blank one procedural DTS-1,P ofBHVO-2, with duplicates processed below,allsample As explained optima-grade H by dissolv solutions wereprepared fi inthecourseof potential fluoridesformed was repeated toachievecomplete digestion HNO dissolvedinamixtureofconcentrated Thesolidresiduewasthen evaporation todryness. at 70–80°Covernightput onahotTeflonplate grad orSuprapure Grade Metal Trace Articlesulfides and ironmeteorit in weighed sample powderwas through a gravimetric approach. amount ofspikeused,wedidnotattemptto by MC-ICP-MS using nickelNIST SRM the g 500 µg together proportiontoobtainafi mixed inknown separatelyconcentrated in distilled HNO OriginalLaboratory. spikesNational inmetalformwere theOakRidge dissolvedprovided by withspikes prepared was The double-spikeused Sample digestion: -1 andwitha -1 HCl and further evaporated to dryness at at dryness to evaporated andfurther HCl 2 O 2 was added to each sample to ensure complete oxidation of Fe. ofFe. oxidation complete ensure to eachsample to wasadded 61 Ni/ es were digested with 5 ml of concentrated HNO with5mlofconcentrated es weredigested 62 Depending on their Ni concentrations, between 50 and 250 mg of and between50 Depending ontheirNiconcentrations, Ni ratioof~1.Thedouble-spikec batches, generally including Teflon beakers. Non-siliceous Non-siliceous Teflon beakers. ingin 10mlof6moll residue the e) and 6 ml of concentrated HNO of concentrated and6ml e) 3 and evaporated at 70 °C. Aliquots of the spikes were andevaporatedat70°C.Aliquotsofthespikeswere determinethedoublespikeisotopecomposition of non-siliceous rocks and ensure removal of removal ensure rocksand of non-siliceous 986 standardsolution.Consideringlimited the and then caps were removed toallow removed thencapswere and rst dissolutionstep ofsiliceousmaterials.Finalrst CC-1, Nod-P-1 or Nod-A-1 CC-1, Nod-P-1orNod-A-1 61 nal double-spike solution at a concentration of nal double-spikesolutionataconcentration Ni (batch127890)and l solutionofNi(Ni a temperature of 70–80 °C.Thislatterstep of70–80 a temperature twenty-four samples, were samples, twenty-four materials such asMn-nodules, materials such oncentration was then determined wasthendetermined oncentration -1 HCl, andonedropof Plasma Calstandard 3 . Closed beakers were were . Closedbeakers 62 3 and5mlof6moll Ni (batch233026) reference materials, materials, reference -1

-1 3

1 Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards ammonia solutionand 4mlofultra-pure water. Nickel was quantitatively eluted fromthe resin was then elut matrix maintain apHof8–9.The with 0.3mlof1moll column,1mlofthe initialsolutionin0.24 loadingmol thesampleonto l mol l initially Conditi water. withultrapure washed at pH8–9.About0.5ml(wetvolume) solutions tobuffer ontheresin,ammoniumcitratewasadded complex formation oftheNi-DMG prevent the co-precipitationofmetals inthe form ontheresin.To retained 8–9 toformaninsolubleNi-DMGcomplex Ni atpH that scavenges ofpol Ni-resin, made The specific metals. earth alkaline and suchasalkali elements rock-forming major including step, purification anion-exchange the after remaining elements below, theNi-spec use ensure ofthe resinrequired ofall was completeremoval matrix to filled witha specific nickelresin commerciallyavailable fromEichrom (Ni-Spec). Asdiscussed 0.24 moll in1mlof dryness at100–120°C on ahotplateandthendissolved thentakento fraction was wa elution work.Nickel column chromatography digestion wereas keptarchive solutions, fractionfinal solutionsin6moll ofthe mol l 15mlof3moll then ml ofultra-purewater, begun 15 loading by columns was ofthe mesh).Thewashing procedure form (BioRad 100-200 filled was with3ml(wet inthe(15 ml)reservoir) volume) chlorideresin ofanionic AG1-X8 columns (i.e.,disposablepolypchromatography and Cooketal protoc chemical purification Accepted Article HClduringZnandmostoftheCoa whichFe, -1 -1 ammonium citrateand11.7moll HCl. Conditioningml of6moll carried was outwith5 Nickel chemical purification byion- -1 HCl.This solutionona wasthenpurified . (2007) and followed a two-stage procedure. The first set of ion-exchange The firstsetofion-exchange procedure. followedatwo-stage . (2007)and -1 ammonium citrate,and0.1mlof11.7moll ol used was adapted from previous work by Cameron Cameron previousworkby from ol usedwasadapted ymethacrylate, contains a dimethylglyoxime (DMG)molecule of Ni-Spec resin was loaded resin was loaded Ni-Spec of -1 -1 HCl on the columns. The final solutions obtainedafter HCl onthe columns.Thefinalsolutions and a only splitwas taken forion-exchange optima-grade ammonia adjusted to pH 8–9. Before to pH8–9. Before optima-gradeadjusted ammonia -1 oning was made using a mixture of2.1ml of 0.2 oning madeusingamixture was exchange chromatography columns: HNO ed with 4.2 mlofmixed ammoniumcitrateand ed nd Cu were retained on the resin. TheelutedNi onthe nd Cuwereretained ropylene columns equipped withalarge-volume columnsequipped ropylene of insolublehydroxides,whichmay inhibit the s achievedbypassing through15mlof6moll 3 , 15 ml of ultra-pure water, and5mlof0.24 , 15mlofultra-purewater, second series of chromatography columns chromatography of second series -1 HClfollowed bythe loading ofa -1 into disposablecolumnsand optima-grade ammonia to to ammonia optima-grade -1 HClwasmixed et al The . (2009) - 0.28 moll ona todryness eluted Nisolutionwasevaporated resin. The reuse ofthe and regeneration any ented prev therefore, with nitricacid.Thistechnique, Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards respectively; material, SRM 986reference where R δ as perfollowing: mildeviation (‰) stable isotopedeltanota scheme reduction data and procedure Mass spectrometry these blanks. betaken toreduce should care areanalysed, sizes anddidnotrequire negligible was considered footnotes (see chemistry through generally processed generally blankswere procedural geologi onthe were notdependent proced publishedexperimental recently yieldsresinthan wereIn 85%,while alwayscontrast throughAG1-X8 quantitative. toanother values blank determine procedural spike/natural ratio (i.e., be equal inthe tothe sample. Nicontent Chemistryyields were using determined the measured amount waschosento below, thedouble-spike sample.Asexplained solution wasaddedtoeach through the purification chemical Before with 8mlof3moll Acceptedx/58 Article Ni =(R Nickel isotope compositionis expr Nickelisotope Delta notation: spl -1 andR HNO spl /R NIST NIST 3 when it was ready for isotope determination. isotopedetermination. for whenitwasready – 1) x 1000 (1) -1 are the isotopicratios the are HNO 62 tion, i.e.,sampleisotopicratiosareexpr Ni/ 3 , which ensured oxidation anddest , whichensuredoxidation 58 Ni). Chemistry blanks were also spiked,whichenabledusto Ni). Chemistry were blanks ca. cal matrix and amount ofnickel andamount cal matrix yields through. Chemistry Ni-s 3–4 ng, and since between 0.5 and > 1 µg of nickel was ofnickel 1 µg 0.5and> since between and 3–4ng, ure for nickel purification (Gall purification(Gall nickel for ure Ni-spec column, aknownamountofdouble-spike column, Ni-spec x x Ni stands for one of the following isotopes: forone ofthethree Ni stands Ni/ any correction. However, when smaller sample when However, correction. any 58 Ni of the unknown sample and thenickelNISTNi oftheunknownsample hot plate at 90 °C and the residuedissolvedin hot plateat90°Candthe in Tables 3, 4, 5, 6 and 7),thisblanklevel inTables3,4,5,6and essed following the conventional theconventional essed following ruction of the Ni-DMG complex Ni-DMGcomplex ruction ofthe essed relative to essed relative pec resin were generally better generally better were resin pec loaded on thecolumn.Nickel loaded on et al . 2012), our yields . 2012),our a standard ratio a standard not exceed 0.5 mV and 0.2 mVonthespikedisotope 0.5mVand0.2 not exceed The main interferences on Ni isotopes included Fe (e.g., (e.g., Niisotopes includedFe on The maininterferences analysis total timerequiredper often whereas washoutconsisted an integr eachhaving cycles, Fifty measurement desolvation introductionsystem. Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards argon generated inthe Ca) oxides min coupled witha50µl al or Al (e.g., other conetypes samples was negligible, the since measured instrumentalblank signal intensity mass on and skimmer conescontribution tothe were (Xcone) ofNi,their Niisotopic made ratios of ml wastypically V/µg resolution modewiththeApexQ ~50–75 Nickel ionbeamintensityNi isotopesasdiscussedbelow.inamedium on interferences resolution mode,butthemedium-resolutionmode interfering Fe monitored at mass of measurement was equippedwithni Thisinstrument France. ICP-MS operatedPôle at theSpectrométrie Océan data inthisstudy is ratherthantothe belongs tothe‰symbol inthedeltanota multiplication factorof1000 thatfollowing Copl note abundant). However, 60 Ni, Acceptedch a spray waseither . (2007).Theinletsystem Article 61 Ni or MC-ICP-MS settings: settings: MC-ICP-MS 62 Ni, andthelight isotope, 58 Ni, 60 Ni/ 60 Ni, Ni, 58 -1 Ni anditwill bereportedas PFA micro-concentricnebulise 61 Pt cones) was unnecessary, as already demonstrated by Moynier Moynier by demonstrated asalready Pt cones)wasunnecessary, Ni and All samples wereanalysed ona was, therefore, approximately approximately was, therefore, 57 measurement cycles,measurement eachwithanintegration timeof4 s.The plasmawith identical masses (e.g., either a medium orhighFe.a mass- Theinstrumentwasrunineither 62 Ni, 58 Ni, is placed in the denominator (it is also the most most the also is (it denominator the placedin is Ni, 63 δ Cu and notation. Theratiothatwill notation. tion couldbepermitted ne Faraday cups that allowed simultaneous Faraday allowed ne cupsthat en's (2011) recommendation, omissionofthe (2011)recommendation, en's ation timeof4s,were ation amber (i.e., Stable Intr amber (i.e.,Stable was sufficient to resolve argide and oxide andoxide argide was sufficienttoresolve (PSO) located at IFREMER, Centre de Brest, deBrest, Centre IFREMER, at located (PSO) 65 Cu isotopes,aswellisobarically- 62 δ Ni. Thisalsoindicated thattheuseof 60/58 58 r) or an ApexQ (ESI, USA) USA) (ESI, an ApexQ r) or Fe on Ni. 4 min (analysis plus washout). 4 min(analysis Neptune (Thermo-Electron) Neptune (Thermo-Electron) MC- -1 58 on Ni), Ar or other element (e.g., (e.g., Ni), Arorotherelement because technically it technically because 40 58 performed onsamples, performed Ar Ni. Although bothsample oduction System (SiS) oduction be usedtodescribethe 18 O + on 58 Ni + ), and 58 Ni did et et isotope inthisstudy. Argide Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards forNiisotopes(<0.1‰) was negligible correction 3‰ permassunit(e mayas byasmuch vary important tonotethatthis isonly correction an solutionat nickelmixed and measurements ofiron (f nickel f M ironratio; natural corrected where ( ( of interference and the measured chemical fromNiduring separated criticalgiven that itaffects the major isotope ofargon oxide. duetotheproduction USA) system (ESI, the ApexQ to resolve polyatomic interferences on 40 36 interference-free ofthe measurement 64 interferencesfrom Xe The isotopes. other major potential spectral interference on etal Fehr reported by argon resu of ultrapure solution; and(3)theuse potentialand(2)no a high first-ionisation ions(e.g., doubly-charged Fe 58 Ar Ar Zn. configurationofth SincetheFaradaycup isthe mass discrimination factor considered equivalent tothe mass discrimination factor of AcceptedFe/ Article 18 25 57 O Mg Fe) correction: interference Fe isotope 58 + Ni , and Fe/ + ), which is generally around 1.8. The disc generally around1.8.The ), whichis , and measured 57 Fe) 42 Ca 38 =( measured Ar 16 23 O 58 . (2004) forTeisotopemeasurements . (2004) Na + Fe/ on on is the raw ratio measured by is measuredMC-ICP-MS; therawratio ( + 57 on 124 58 Fe) Ni and oxide interferences included interferences and oxide Xe 61 58 natural + Ni . Medium-resolution modesallowedus (andalsohigh-resolution) istheatomicweightof 2+ 58 + on ; Fe on .(M purification prior to analysis, toanalysis, prior purification 36 Ar 66 62 58 Zn isotope, we did not attempt to measure the Zn wedidnotattempttomeasurethe isotope, Ni). The latter was negligible has considering (1)Xe that 58 26 Ni 58 /M Mg 124 Ni was corrected using Equation 2: Equation using Ni wascorrected + , which stillremained significant even when using 57 Consideration ofisobaric interference fromFewas Xe .g., Dauphas and Rouxel 2006). However, this 2006).However, Dauphas andRouxel .g., + 58 , ) approximation since the natural Fe isotope ratio sincethenaturalFe isotope approximation fFe Ni. Therefore,evenFe quantitatively if was e mass spectrometer didnotallowsimultaneous spectrometer e mass 38 lted innegligible aspreviously lted Xeintensity, 2+ Ar (2) was measured on mass 62 intheblank onmass62 was measured the beginning of each analytical session. It session. analytical is each thebeginning of given that iron interference was very small wasvery given thatironinterference rimination factorwa 24 Mg 58 + Fe; M Fe; , and withpotentialimportantisobaric 36 46 Ar 57 Ca 57 isthe atomic mass of 24 Fe was systematically Fe wassystematically 16 Mg 58 O Fe/ + + s estimatedbasedon on on and 57 Fe) 62 44 Ni natural Ca + ; 16 64 23 O is the Ni isfrom Na + 64 on 35 Ni 57 Cl Fe; and 60 + Ni , + ; Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards this Hence, artefacts. analytical by significant ofpurified compositions 99%, itispossiblethatCu-corrected Niisotope recovery nickel that Considering (R (R (Equation 4). us tousef sessions, whichallowed Niisotopes;(2)f as mass fractionationlaw isotope ratiosofNIST SRM976 relationship (plotnotshown)be fractionationbeingwith the fractionation law“f” each factor specific The element. for linear Marechal instrumentalmassbi for which isusedtocorrect amountof method isbasedonaddingaknown fo waslowerthan precision analytical why the each and after solution wasmeasuredbefore instrumental massbiasusing thecalibrato ofNISTratios. TheNiisotopecomposition minor amountsofiron(Fe/Niratiosfrom0.001to SRM 986solutions dopedwithvariousamountsof we estimated the ofnickel irononthe effect of isotopic by composition measuring several NIST afterchemical when separation, ironwas quantitatively removedanalyte. fromthe Additionally,

Acceptedmeas meas Article /R /R Inter-elemental correction of Ni instrumental mass bias using Cu isotopes: isotopes: Cu using mass bias instrumental Ni of correction Inter-elemental true true et al ) ) Ni Cu =(M =(M -ICP-MS follows an exponential mass- massbiasonMC-ICP-MSexponential . 1999),instrumental followsan 60 65 Ni/M Cu/M 58 63 Ni) Cu) fNi tween logarithmstween SRM986andCu ofNiisotope ratiosofNIST fCu yield on the Ni-spec resinpurifi yield ontheNi-spec confirmed that (1) Cuisotope confirmed that(1) (4) (3) Cu determinedonNIST 3)tocalculatef SRM976(Equation r-bracketing method (a non-doped NIST SRM986 method(anon-doped r-bracketing Cu SRM 986 Fe-doped solutions was corrected for SRM 986Fe-dopedsolutionswascorrected /f Fe-doped NIST SRM 986 solution), which explains Fe-doped NIST SRM986solution),whichexplains correction method is only suitable for Ni-rich ores forNi-rich method isonly correction suitable Ni r the samples corrected with the double-spike. withthedouble-spike. samplescorrected r the Cu standard solution (i.e., NIST SRM976), standard solution(i.e.,NIST Cu was constantduringindividualanalytical as. As demonstrated in previous studies(e.g.,as. Asdemonstratedinprevious 0.010) didnotproduceany biasinNiisotope iron. The results (see Table 1)showthat (seeTable iron. Theresults s follow the same exponential s followthesameexponential cation step ranged from 85%to rangedfrom cation step samples were affected affected were samples This Ni

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards asathree-dime spike methodcanbevisualised etal byupon themethoddescribed Siebert 2. presented inTable rinsetimeand double-spike solution,anextended solution andthe In betweenthestandard spike solution. toavoidcross-contamination order solution was used tocalculate the f 61 methodtodeterminethetrue usingwas thendetermined theCu-dopingcorrection isotopic ratios,i.e., calculate mass-discrimination the instrumental factor f a The isotopiccompositionofNIST SRM986wasfirs RM are calibratedsame onthe instrument spike andRMisotopecompositiondonotintrodu Indeed, bySiebert previously instrument. asdiscussed bothisot tocross-calibrate critical therefore isotope ratios might be influenced and by the ofinstrument instrumental type settings, and itis yield precisecompositi does not asufficiently such asNIST SRM986(Gramlich nor orafter gravimetrically determined either thedo Determination of usingNi isotopedataobtainedCu al and ironmeteoritespur Ni/ 60 Accepted Article. 2006,Moynier Ni/ 58 Ni and 58 The double-spike calculation procedure was based procedure calculation double-spike The scheme: correction spike Double Ni ratioof0.385199 ± 0.000728(2 62 Ni/ et al 58 62 Ni ratios ofthespikevs.NIST SRM986.ACu-dopedpurestandard Ni/ . 2007,Cook ified through anion-exchange resin as throughanion-exchange ified 58 uble-spike composition: composition: uble-spike Ni and 61 -doping and double-spike methods. -doping anddouble-spike Cu Ni/ et al et al /f 58 Ni . 1989). In practice, however, Ni. Theisotopic composition ratio, which was then applied toCu-dopedpure double- ratio,whichwasthenapplied . 2008). Inwas usedtocompare . 2008). addition,thisapproach and that isotope data are expressed as expressed isotopedataare and that . (2001) for Mo isotope determination. Thedouble- forMoisotopedetermination. . (2001) s ope reference materials and spike onthesame andspike materials ope reference ) (Gramlich malisation to a known isotopic reference material, material, toaknownisotopicreference malisation on for small quantities of spike. In smallquantitiesofspike. addition, on for nsional diagram where axes represent the three the three represent axes diagramwhere nsional ce bias providing that both doublespikeand thatboth ce biasproviding “on-peak zero”method Incomposition canbe double-spike theory, t determined by intern t determinedby Ni et al , which allowed the calculation of other calculationofother , whichallowedthe et al . (2001), uncertainties onthenatural . (2001),uncertainties . 1989).Thisratiowasthenusedto used in previous studies(Quitté used inprevious the gravimetric technique the of thenickeldoublespike was used.Resultsare al normalisationusing δ 60/58 60 Ni/ Ni values. 58 Ni, et et Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Acceptedsamples withnickel concentr of theprecision spike correction, MC-ICP-MS during thedouble- acquisition.With ofmeasurement cycles fifty calculated on mean the error of standard asatwo reported is precision measurement the analysis, For each Measurement precision andlimit ofdetection Results of analytical method development ng, by MC-ICP-MS. nickel,downto50 t ofvery smallamountsof measuremen accurate session);and(iv) analytical instrumental mass bias and the assumption that f rati corrected (because precision overall analytical concentra and accuratenickel separa chemical fractionation during bracketing or sample-calibrator double spikemethodoffers that ofthesamples.The Articleof NIST SRM986nickelsolutionsatthesameni bymeasurements the wasbracketed analysis sample Each analysis. sample during acquired were integration time) tical cycles (~4minoftotal analy In fifty toobtainsatisfactory precision, order Matlab™. orusing spreadsheet either onanExcel™ run toproperly iterations were tothemeasur appliedsubsequently which were toaccountforbothna making calculations iterative (AlbaredeBeard Atemplate and 2004). established tocalculate was those plane intercepts by used todetermine fractionati byMC-ICP-MS, are andsamplemeasured compositions ofthedouble-spike,standardsolution asspeci measured isotopicratios on factors between the measured and corrected isotopic ratios ratios isotopic andcorrected measured the between on factors ations ranging from 100 ngg ations rangingfrom100 tions of samples using theisot tions ofsamplesusing obtain the fractionation factors.Th thefractionation obtain methods by allowing: (i) the correction of potential isotopic ofpotential correction (i)the methods byallowing: fied above.Line and plane in δ 60/58 tion through Ni-spec resin; (ii) tion throughNi-specresin; Ni values was usually around ± (2SE)for Ni valueswasusually 0.02–0.04‰ ed raw isotope ratios. Atleasttwonested rawisotoperatios. ed Cu ckel concentration and spike/standard ratio as ratio andspike/standard ckel concentration os were less affected by the stability the by of os werelessaffected /f tural andinstrumental several advantages relative totheCu-doping relative advantages several Ni remainedconstantthroughout the -1 to 1 µg g to1µg opic dilutionmethod;(iii)better tercepts, defined by isotopic defined tercepts, e template could be performed couldbeperformed e template the determination of precise ofprecise thedetermination -1 . Precision atlower . Precision fractionation factors, fractionation Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted tothewas precisionrepeatability similar (n= under duplicates BHVO-2 calculated 11) for 0.041‰ (2 of 3 fordetails).Avalue Table of (seefootnotes samples ofthese analyses PCC-1,DTS-1, DNC-1,BIR- materials (BHVO-2, The precisionunderintermediate measurements. for 320 a valueof0.045‰ method. For 2 instance, compositiondeterminedby oftheNiisotope thedouble-spike conditions intermediate precision 986allowedusto for NIST SRM set acquired NIST SRM986Niisotoperatiosdeterminedduring wenormaliseddelt session.Asaresult, analytical within 0.02–0.05‰(2 remainedconstant sessionsbut unit betweenanalytical to0.2‰permass NIST usingmethodmay byup thedouble-spike SRM986calculated deviate an (CSB) bracketing similar tothecalibrator-sample A spikedNIST SRM986solutionwasmeasured Article RMs 986and NIST SRM of precision measurement Intermediate systems ontheMC-ICP-MS instrument. 100–200 ngg of nickel concentrations For optimummeasurement precision during measurements, isotope we usually ran samples with of nickel. g ± at10ng 0.07‰,butbecame worse showsthatbelow30ngg and nickel concentrations, the against reported is analysis foreach calculated mean the errorof standard two 1,the Figure NIST analysing by wasassessed concentrations s determined using all NIST SRM986 de determinedusingallNIST precision conditionswasalso -1 -1 , when using either the ApexQ or SiS introduction orSiS theApexQ either , whenusing and lower concentrations, e.g., 2SE = 0.59‰ at 2 ng g 2SE=0.59‰at2ng e.g., concentrations, andlower evaluate the measurement precision under precision themeasurement evaluate SRM 986 solution at different concentrations. In SRM 986solutionatdifferentconcentrations. before and after each sample inamanner sample each and after before a values of the samples relative to the average totheaverage relative a valuesofthesamples 1, Nod-A-1 and Nod-P-1) using duplicate Nod-P-1) 1, Nod-A-1and the same analytical session. The large data Thelarge data session. analytical thesame -1 alysis. We found that the Niisotoperatiosof alysis. Wefoundthatthe the precision slightly deteriorated toabout slightly theprecision deteriorated estimated for certified reference reference certified estimated for lta values calculated so far gave far lta valuescalculatedso s ) during each each ) during s ) -1

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted (notincluding freedom of samples and23degrees 2s purificationprocedure), the spikedafter BHVO-2 similar. From data inTable3withfive samples 21degrees and freedom(notincluding of the mean. Thismethodisa where = k s² (5) (Steele conditions wouldbetopoolallth anothermethodforestimatin Alternatively, standard solution. value of0.020± (2 0.065‰ yielded anaverage 2) (Figure procedure chromatography entire the through processed science) ArticleIn themono-elem addition, ofnickel. and 5µg 0.2 i.e.,between chemistry, the through ofsamplematerial processed amounts even fordifferent theisotopi important tonotethatforBHVO-2 and 7),whichissimilartothein andtheir duplicate RMs, i.e.,PCC-1,Nod-A-1,N Ni-resindidnotin ofNithroughthe recovery sample and after spiked before results gave similarvalues,i.e.,0.006± 0.041‰(2 purification. Although onesamp only complete purificationprocedure variability Oneofth inisotopemeasurements. conditions. Thissuggests thatthechemical -1 s ∑ is the standard deviation, deviation, isthestandard i d et al i 2 (5) . 2011): δ 60/58 ppropriate when conditionsofsampleprocessing ppropriate when Ni values generally did not deviate by more than 0.069‰ (2s morethan0.069‰ generally didnotdeviateby Ni values s , n=tothat fordirect 24),which issimilar analysis ofNi-PCal od-P-1, BIR-1, DNC-1 and DTS-1, were also analysed in analysed also andDTS-1,were DNC-1 od-P-1, BIR-1, purification, respectively. This indicates that theincomplete purification, respectively. Thisindicatesthat termediate measuremen to evaluate potential Niisotope evaluate potential to e data and to calculate thest e dataandtocalculate k is the degree of freedom and freedom of isthedegree le was spiked subsequentto was spiked le termediate precision precision underintermediate g the purification methoddidnotintroduce additional purification troduce Ni isotope fractionation (Table 3). Other (Table3).Other Niisotopefractionation troduce c composition and recovery remained invariant remained andrecovery c composition e BHVO-2 basalt duplicates was spiked after a was spikedafter duplicates e BHVO-2basalt ental solution of Ni-PCal (Ni Plasmacal®, SCP SCP (NiPlasmacal®, ental solutionofNi-PCal single measurements on USGS G-2, IF-GUSGS G-2, and single on measurements s ) and-0.067± (2SE)forthesamples 0.017‰ was 0.045‰; from data in Table 7 with six inTable7withsix was0.045‰;fromdata t precision of NIST SRM 986. It SRM986. t precisionofNIST isalso andard deviation using Equation deviation andard fractionation during chemical during fractionation d isthe deviation fromthe the purification procedure, the procedure, the purification and measurement are

; Tables3 δ 0.01 ± values clusteringaround 0.02‰.Evenspike/sa Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards ratio~ 1throughoutstudy. weusedaspike/ sample this and 8, ratios between0.7 yielded(2SE) and-0.24± higher forNIST ratios SRM986,whereas than0.6 0.06‰ spike/sample ratioslower samp As showninFigure under-spiked 3,only NISTdouble-spike mixture. SRM986andthe intensities (correctedinstrumental mass for bias), isotopic masses, and true SRM986),thespike/ ofNIST spike/concentration of ratio(concentration a concentration gInstead reportin of theratio). ofsimply from nickel whereas ratio), (denominator ofthe sample from theNIST inanatural SRM986solutionisequivalentto the nickelpresent ratio,oneshoul ratios. Tosimply visualisethemeaningofspike/sample solutions added tomakefinal ofNIST SRM986waskeptfixe concentration correction. the robustnessofdouble-spike ratios (b withspike/sample different undertaken Several testswere Optimum spike/sampleratio for Niisotope determination precision'). ('external reproducibility measurement ng the for assessi adequate study bothmethodswere following Steele deviation calculated themethodologyof NIST SRM986 reproducibility of as themeasurement 2 freedom), of samples and44degrees NIST SRM2711),2 Accepted60/58 Article Ni valuesof0.04± 0.02‰.Although anoptimum s was 0.053‰. Taking samples from both Tables 3 and 7(i.e.,eleven 0.053‰.Taking frombothTables3and was samples or equal to 0.6 yielded or equalto0.6 with different spike/sample ra with differentspike/sample s was 0.050‰. Hence, the 2 Hence,the was0.050‰. For each sample used for the tests, the forthe each sampleused For d and different amounts of double-spike were amounts ofdouble-spikewere d anddifferent les may not be properly corrected. Indeed, corrected. mayles notbeproperly the double-spikesolutionisspike(numerator δ 60/58 sample ratio was calculated using measured sample ratiowascalculated mple ratios of up to 7 gave consistent mple ratiosofupto7 Ni values ranging between -0.05±Ni valuesranging between 0.02‰ (see above) is comparable to the standard tothestandard iscomparable (see above) precision was obtained forspike/sample precisionwasobtained et al tios, which is tantamount to tios, whichistantamount . (2011), indicating that inour that . (2011),indicating etween 0.03 and 8) to evaluate 0.03 and8)toevaluate etween s value of 0.045‰ calculated 0.045‰calculated valueof d considerthatnickel 61 Ni/ 58 Ni ratiosof δ 60/58 61 Ni/ Ni 58 Ni for Cuand>10 Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards to monitorall natural Niisotope ratios. Ass me bracketing acalibrator-sample using analysed interferencesfrom calcium (e.g., oxides elementsproxyfor matrix-forming insilicate rocks. good Ca,whichisa also donewith solutions.Thesamewas in analysed and 0.5 ratios between2 of the influence column purification,wetested with Caand separately effect Potential matrix high amountsofiron. ifsampleshad even chemical procedure during the >>10 efficiency (separation solutions from interference 64 10 as10 as low > 10 purification,was after divided byelementremaining themassof estimated separation efficiency factor,the defined asmass (g)an element of loaded onresin concentrations inpurifiedsamples were all Brest. II)at PSO, X-series (ICP-Q-MS, ICP-Quadrupole elementswithan ofmatrix concentrations measuring basalts andshale)by checked was Chemical purificationefficiency Evaluation of potential matrix effect ~0.6and4, spike/sample ratiosbetween optimum spike/sample ratio. Calculations indicated that the best results were obtained with The Matlab®templatec Ni wasnotconsideredinourdouble-spikecalc

Accepted6 Article ), although care should betake ), although should care 3 . On the other hand, Zn was well separated (s Zn wellseparated was . Ontheotherhand, 7 for Mn. Titanium was found more difficult Titanium wasfoundmore forMn. 64 Zn was not critical for our study. Iron was not detected in all analysed inallanalysed Iron study. wasnotdetected Zn notcriticalforour was s were further assessed using seve assessed using further s were S. Since several Ni-rich sulfides we Ni-richsulfides S. Sinceseveral et al onstructed byRudgeet ing sample preparation. Since Zn duringpreparation. n toavoid contamination sample 6 ), which suggests that quantitatively ironwas separated andchemical purification efficiency Potassium, Na,Ca,Cr, 40 Ca which is consistent below thebelow detection limitofthe instrument. The hown in Table 1, the results suggest that isobaric thatisobaric hown inTable1,theresults suggest 18 for a number of RMs (e.g., manganese nodules, a numberofRMs(e.g., for O on sulfur on the instrumental mass biaswithS/Ni ontheinstrumentalmass sulfur ulations andfinalresu ulations thod and without a nickel double-spike inorder andwithoutanickel thod . (2009) allowed us to further evaluate the evaluate . (2009)allowedustofurther Calcium isalso a sour 58 Ni). Matrix-doped nickelsolutionswere Ni). Matrix-doped ral NIST SRM 986 solutionsdoped ral NIST SRM986 eparation efficiency factor betterthan factor efficiency eparation re analysed without Ni-specresin analysed re to separate with a separation factor factor aseparation with to separate withourresults. Mn, Fe, Mo andCo Mn, Fe,Mo lts, potential isobaric lts, potential 6 for Na and Mg, ~10 and Mg, forNa ce ofpotentialisobaric ce 6

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Acceptedigneous incl isotope valuesinvarious rocks, compare Niisotopefractionation It isimportant estimate tohavean ofthe Bulk Silicateto interpret Earthvalue and inorder Assessment ofthe Bulk Silicate Earth (BSE)Niisotope composition Sample analysis results and discussion the doubl of validate thereliability uncertainties the total range for of cal AsshowninFigure4,values correction. anddouble-spike entireprocedure involvedpurificationthrough the method doping. Thesecond anion-excha purification through involvedsample method massbiasusing methods.One instrumental two different for corrected Several sulfides aswell asand Ni-rich analysed ironmeteoriteswere (i.e., Ni-rich meteorites) Articlemass bias Comparison between Cu-doping and double-spike correctionmethods for instrumental non-doped NIST SRM986. isthetwostandarddevi precision The reported instrumental massbias for corrected and Swere section onMC-ICP-MSNIST SRM986dopedwithCa valuesfor settings), measuredNiisotope fromCaO. interferences resolved majorisobaric Ca/Ni = 1and S/Ni= 1,respectively. also imply Theseresults the that medium-resolutionmode yieldingand 0.5, between 1 interferencesand ininstrumental changes mass bias were insignificantelement/Ni for ratios δ 60/58 nge resin andinstrumentalma nge resin Ni valuesof-0.18± 0.14‰ (2 in natural samples. Hence, our approach was to measure Ni tomeasure was approach Hence,our in naturalsamples. δ e-spike data re e-spike data 60/58 Ni values from -0.60‰ to 0.40‰. These results further Ni valuesfrom-0.60‰to0.40‰.Theseresultsfurther culated withthetwomethodsfallwithin culated uding oceanic basalts and Archaean komatiites.The andArchaean oceanic basalts uding ation value based on replicate measurements of measurements replicate ation valuebasedon using the sample-calibrator bracketing method. method. bracketing using thesample-calibrator Note thatsimilartotheFe-doping (see tests duction scheme. scheme. duction ss bias correction basedonCu- ss biascorrection s ) and 0.02 ±) and0.02 0.14‰(2 s ) for e Logatchev hydrothermal field hada Logatchev field hydrothermal Serpentinitefromthe positive valueof+0.10‰. olivinecrystals displayed+0.07‰, whilehand-picked yielded aslightly more of Loihi avalue BSE Ni which isimportantfordetermining the (Kurz values between -0.10‰ and +0.15‰; BHVO-2 gave a near zero zero gave anear +0.15‰;BHVO-2 -0.10‰and values between h’s mantle as indicated by their highprobably mantleasindicatedbytheir derivedfrom deep enrichedEarth’s the (Logatchev field).Fresh pillow basalts from Lo Seamount)andse (Loihi samples fromHawaii 2s Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards toanas or heterogeneity material reference inth smalldiscrepancy The (~+0.1‰). BHVO-2 In Gall contrast, for BHVO-2. with values up to+0.34±systematically 0.08‰ (2 heavier published previously For comparison, significant. beconsidered to uncertainty analytical the to close of a smallrange IODP 1149,displayed and core fre BIR-1, DTS-1andPCC-1) DNC-1, (BHVO-2, reported inthisstudy.Insummary, all mantle-derived rocks analysed inthisstudy, i.e., RMs Ni with agreement in andare basalts, altered δ (Plank etal Incomposition of-0.07‰. addition, perido value of-0.13‰,whereas ultramafic RMs(i.e., basalt,dunite and peridotite) closelyclustereda range within of mantleisotopecomposition. Earth’s theearly represent of themodernman yieldestimate an former 60/58

Accepted ArticleFigure 5display isot and , n=11).Table4 Ni values between -0.03 and +0.10‰, without an and+0.10‰,without Ni valuesbetween-0.03 et al Igneous and ultramaf . 1983). Therefore, they might represen they might . 1983).Therefore, . 2000,Rouxel etal ic rock ic rock samples: et al . 2003) were also analysed (Tab also analysed . 2003)were tite PCC-1hadthevalueof . (2012) obtained resultssimila . (2012)obtained fresh andalteredbasaltsrec δ 60/58 Ni values (figure 5 in Cameron Ni values 5inCameron (figure tle isotope composition,whereasthelattermay tle isotope yet unclear difference in analytical methods. inanalytical yet difference unclear opic and chemical compositionofthebasalt and chemical opic isotope values for other mafic igneous rocks igneous rocks other mafic isotope valuesfor rpentinite fromtheMid-AtlanticRidgerpentinite isotope composition. Fresh glass isotopecomposition.Fresh from material ihi Seamountwereselect ihi As presented in Table 3 and Figure 5,maficand Figure inTable3and As presented δ e data, although minor, e data,although 60/58 t themostprimitivemantle composition, Ni values,lessthan0.1‰,whichistoo sh and altered basalts from Loihi from seamount altered basalts sh and y significant difference between fresh and fresh between y difference significant s ) for PCC-1 and +0.13 ±) forPCC-1and 0.03‰(2 +0.12‰ and dunite DTS-1hada +0.12‰ anddunite le 5 and Figure 5). They gave 5).They and Figure le 5 overed at IODP coresite1149 overed at δ 60/58 r tooursforbothPCC-1and Ni value (0.01± 0.04‰, ed since they were ed might to berelated et al . 2009)are 3 He/ δ δ 60/58 60/58 4 He ratios Ni Ni s ) Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Acceptedvalues aslow-0.82±0.02‰, withmost Zimbabwesulfidesthat from show a systematic enrichment inlowatomic number isotopes to magmatic Ni-rich Archaean for data isotope Ni recent by confirmed further is interpretation pr Ni isotopestookplaceduringthemagmatic fractionation inkomatiites, ourresults clearly dem isotope composition ofkomatiites.yet Regardless as ofthe, unclear, mechanism ofNiisotope toobtain didnotexpect BSE composition,andwe The choice these of sampleswas essentially motivated by ourattempt toassessa value the for 0.26 to-0.10‰. whereas olivine minerals and pure komatiite samples wereclosebasalt tomodern values, from- were values, from-0.62to-1.03‰, -0.10to-1.03‰(T these samples,rangingfrom large Anunexpected BE-2). (BE-1and separates composed ofalmost purekomatiitic materials (B andA) twosamples were olivine mineral otherswere MC-1,TD21,MKTD76), dominated by mineralisation(AX-1,AX-2, pentlandite were representative of Ni-sulfide-mineralised Article obtainedforig values of fall intherange δ As expected, ofth asrepresentative composition canbetaken Niisotope their continents. Therefore, origin fromthe derived both detritalandchemical repos sedimentsarethe Deep-sea onEarth. important sedimentary reservoir the mostcommoncomponentofsedimentson fresh 1149 along and withaltered Ni isotope composition of koma of Ni isotopecomposition Ni isotopecompositio 60/58 Ni values of +0.04 and +0.02‰ for deep-sea clays (Table 5, Figure 5) clearly clearly 5,Figure5) clays (Table fordeep-sea +0.02‰ Ni valuesof+0.04and Deep-sea clays were collected at IODP at site collected clays were Deep-sea clays: deep-sea of n basalts describe basalts determined on samples withelev on determined neous and ultramafic rocks in our study. inourstudy. ultramaficrocks neous and tiite-hosted Ni-sulfide ores: Ni-sulfide tiite-hosted values clustering around -0.40‰ (Hofmann around -0.40‰ values clustering ultramafic magmas. While some samples were ocesses that formed these rocks. This rocks. thatformed these ocesses able 6, Figure 5), butthemostnegative 6,Figure5), able e average composition of the continental crust. crust. continental ofthe composition e average range of Ni isotope values was measured on wasmeasured ofNiisotopevalues range d above(Plank oceanic seafloor; hence they represent an represent they hence oceanic seafloor; onstrate that significant abiotic fractionation of such a large range of variation intheNi ofvariation range such alarge et al ated content ofpentlandite, content ated . 2000). Clay minerals are Clay are . 2000). minerals Our komatiite samples itory of ofmaterials et al δ 60/58 . Ni Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Acceptedinferences other fromstudiesstable precluding of a isotopeestimate straightforward systems, of 2006, TengRouxel to non-traditionalisotopes,including a Mg isotope systems traditionallowat rangingfrom temperature mass-dependent fracti could be potentially toinvestigate used crystallisation processes at system the magmatic scale. promising totheirubiquitousoccu resultscoupled athighthat govern Niisotopefractionation temp inma and crystallisation effects indicates that Niisotopes are at least as sensitive asFe isotopes tohigh-temperature processes Niisotopeva of of ~0.2‰.Sincetherange magmatic differentiationFe inthe KilaueaIki produced (Hawaii) lava lake Feisotopefractionati temperature either crustalcontamin to -0.30‰in from+0.36 witharange samples waslessvariable, Article high temperatures at occurring Ni isotopefractionations theobserved Therefore, and reservoircrustal ismostprobablybefrom a sourced linked withpartial mantle melting. sulfidesaturationto promoted emplacement, which reactions. Although Sisotopes indicate crustal forsulfurduringcontribution komatiite itunde where poor atmosphere, suggest that these values negative reflectass previously yielded negative All Archaean komatiite samplesand associated mineralisation Ni-sulfide from thisstudy komatiites ofNi-rich reflectsulfides. contribution the submitted). Therefore,seems very it likely that negativeNi isotope valuesmeasured these for Ni isotope composition of theBulk Silicate of Ni isotopecomposition Earth: et al ation orhigh-temperatu . 2008). Our results for Ni isotopes are, forNi . 2008).Ourresults Δ 33 (i.e., abiotic Ironfractionation). S values(Table6;Bekker rwent mass-independent frac rwent mass-independent iled discussion of parameters ofparameters iled discussion gmatic adeta Although systems. on has been documented by Teng by Teng on hasbeendocumented onation processes have been infe havebeen onation processes nd Fe Dauphasand Young andGalynd (e.g., 2004, riations reported in our study was ~0.90‰,it reportedinourstudywas riations imilation ofsulfurprocessedthroughan oxygen- re fractionation (Bekker re fractionation omic number isotopes, O and S(e.g., 2001), omic numberisotopes,Oand Eiler erature is beyond the scope of this paper, these ofthispaper,these isbeyond thescope erature are solely the result ofmagmatic processes rrence in mantle rocks mean thatNiisotopes inmantlerocksmean rrence form sulfide mineralisation, Niisunlikelyform sulfidemineralisation, to et al tionation during photochemical Mantle heteroge . 2009). Bekker Bekker . 2009). to some extent, consistentwith tosomeextent, isotope composition ofthesame isotope composition terpreted as being the result of beingas the terpreted rred from studiesofstable from rred et al et al . (2008), whoshowthat . (2008), isotope fractionations . 2009).High- neity andhigh- neity et al . (2009) metals suchasNi,Cu,Zn andCoformin Mn-nodul respectively. and +0.36‰, values of+1.03‰ Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Acceptedgave oceans andPacific Atlantic the from samples composite represent that Nod-P-1) fromseawater eitherdirectly sources, derived pr sediments organic matter-rich water column insediments. orduringdiagenesis Hence,values positive Niisotope inmarine organometallic and complexes, withironsulfides (e.g., whichformeither pyrite), may inthe et al 2004,BrumsackTribovillard (e.g., Algeo andMaynard 2006, metals such Cu,Vand as Zn, Mo,Ni,U, metal/Al leading to ratios well above crustal values by arecharacterised shales 1961), organic-rich for bulkcr proxyas a generally considered are Although withinteresting shales forfuturestudies. prospects environments temperature positive values relativeBSE Niisotope provide fractionationinlow- strongevidence for to USA) gave (Maryland, and CLB-1 coal USA) Kentucky, Ohioshale(Morehead, Devonian namely SDO-1 ArticleNi isotopesin BSE. compositionof clays oftheNiisotope improvesourunderstanding minerals suchasdeep-sea our in analysed rocks ofmantle-derived range Steele 0.036‰ determinedby BSE estimate Our reproducibility). 0.05‰ (measurement common basalts of composition totheaverage value -0.1 and between~ rocks, from mantle-derived δ in range observed a narrow we since However, value. Earth Silicate Bulk the . 2011). In marine sediments nickelhasast In. 2011). marinesediments Geological reference materials materials reference RMs:Geological Mn-nodule samples: matter-rich Organic δ 60/58 selected RMs RMs selected Ni valuesof+0.58‰and+ et al of isotopically heavy nickel contributionofisotopically heavy the reflect obably . (2011) on Japanese basalt JP-1 basalt . (2011)onJapanese Samples containing c Sampleshigh ustal composition (e.g., Turekian and Wedepohl andWedepohl (e.g., composition Turekian ustal 0.47‰, respectively (Table 7 and Figure 5). These 5).These and Figure 7 (Table respectively 0.47‰, or in association orin deep-sea sediments generally at water depths depths generallyat water sediments deep-sea study and the inclusion of common sedimentary inclusionofcommon studyandthe authigenic enrichments of redox-sensitive enrichments trace authigenic of redox-sensitive +0.1‰, we feel confident to ascribe the BSE ascribethe confidentto wefeel +0.1‰, rong affinity to organic matter, forming forming matter, toorganic affinity rong and mantle-derived rocks, whichis+0.05±rocks, andmantle-derived es are typically enriched intransition enriched es aretypically of manganese nodules (Nod-A-1 and nodules(Nod-A-1 of manganese is slightly thatof+0.179± lowerthan et al with organic matter. matter. with organic ontents of organic matter, ontents oforganic . 2006,Scottetal and dunite DTS-2. The large andduniteDTS-2.Thelarge 60/58 Ni values . 2008,Scott δ 60/58 Ni Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted hold trueforMn-noduleCdisot The samemight seawater. of strength ionic high the because of probably Cd seawater with compared fractionated w thatCdisotopesincorporated (2010) argue on Fe-Mn(Gueguen oxides results onnickeladsorption growth. Similarly, Niisotopes might be affectedthis mechanism by revealed as by experimental which in porewaters, developed closed system equilibrium fractionation during preferential adsorp Rehkämper intheNi responsible forvariations are whichoftheseprocesses to establish clearly areneeded dataset, nodules, aswellalarger theseme contribution ofeach regarding the surfaces. entirenodule tocover observed have been (4) matter re-mineralisation, matter tothesediments a high oforganic supply (3)biological produ ontooxyhydroxides, seawater from directly growth, (2)adsorption ofmetals during nodule scavenged ontoMn-oxides Article with sediments (e.g.,associated processe (1)diagenetic suchvariations: explain withothermetalisotopesystof nodules,compared tomechanismsinvolvedintheformation and indicatesthatNiisotopesareparticularly sensitive massuni twonodulesislarger(per between these 2004) andCdisotopes. ofMo(Anbar exception 2004; Rehkämper 2010, Schmittetal (Dideriksen for previously analysed These noduleshadbeen individual Mn-nodulescollectedfromtheAtlantic of alarge number from RMswereprepared twoMn-nodule The interface. at thesediment-water concentri and 6km.Theyconsist of between 4 et al et al . (2002) argue that variations inTl argue that variations . (2002) . 2006), Zn and Cu (Bigalke etal (Bigalke Zn andCu . 2006), et al . 2009, Cloquet . 2002), highlighting differences in their isotopic composition withthe highlighting intheirisotopiccomposition . 2002), differences in situ organic matter) were released were organicmatter) isotopecompositionofFe-Mn nodules. biological activity, specifically that of microbial mats,which biological thatof activity, specifically et al . 2005),Mo(Barling ith Mn-oxides intoFe-Mn were not crusts ith Mn-oxides chanisms tothecompositionchanisms ofpolymetallic cally laminated Fe-Mn oxyhydroxides precipitated s through which metals contained in subsurface insubsurface s throughwhichmetalscontained are an important source of metals forMn-nodule animportantsourceof are The difference inNi Thedifference other isotopic systems (Table 8) such as Fe 8)suchas isotopicsystems (Table other ope compositions thatprobably biotic reflect ope providing metalstopor t) than for any other studiedisotopesystem,t) thanforanyother . 2010,Chapmanetal . ctivity insurfacewhich could waters, result in isotope ratios of Mn-nodules reflect isotoperatiosofMn-nodulesreflect ems. Several processes ems. Severalprocesses 5). 7andFigure (Table and Pacificoceans tion ofheavy ina Tlisotopes ontoMn-oxides It investigations thatmoredetailed isclear et al . 2011). Alternatively, Horner Horner . 2011).Alternatively, et al into pore waters andthen intoporewaters . 2001) and Tl(Nielsenetal . 2001)and isotopecomposition . 2006), Cd (Horner . 2006),Cd(Horner e waters during organic- waters during e could be inferred to beinferred could et al et al . . . soil sampleNIST SRM 2711(Table7a Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted ofδ range the with agreement full in also are Our values with datainCook Table 5;2 TheIron meteoritesNantan Gibeon and bothdisplayed fairly similar positive variations. w reservoirs extraterrestrial concerns mainly 2007, Regelous (B processes nucleosynthetic Since the firstNiisotope measurements onmeteoritic were made materials tostudy comp and to rocks Ni-rich on procedure analytical goalsOur main inmeasuring ironmeteorite were samples toimplement ourexperimental and ironmeteorites of Ni isotopecomposition (Table 7). IF-G inheavyNiisotopesof+0.45‰ Formationan enrichment sampledisplayed suggesting variabilityNi isotope ratios inwithincommon continental Finally, rocks. Iron the Article Niisotopes heavy in significantly enriched was content nickel low very G-2with granite contrast, In (see above). clays deep-sea Pacific to river sedimentwith to close, withinuncertainty, +0.14‰, whichisvery bybiologicalactivity,affected alt Niisotopesinprecipita suggestthat therefore We intheirdepletion example, for (and zinc), (Schmitt fractionations rather bymicro-organisms than Other RMs corresponding to major terrestrial reservoirs: terrestrial tomajor RMscorresponding Other et al s calculated on duplicate analyses) of duplicateanalyses) on calculated . 2009). The chemical behaviour of nickel in seawater is akin tothatofcadmium isakin nickel in seawater behaviourof . 2009).Thechemical et al et al δ . 2008,Chenetal 60/58 . (2008),whoobtaineda δ Ni values of +0.10 and +0.13‰, respectively (Cameron (Cameron respectively and +0.13‰, Ni valuesof+0.10 irck andLugmair Cook 1988, hough this remains to be demonstrated. hough tobedemonstrated. thisremains . 2009), the available dataset of available dataset . 2009),the nd Figure 5) was found to have a 5) wasfoundtohave Figure nd with a +0.43‰ value (Table 7 and Figure5), 7and +0.43‰ value(Table with a surface waters upon their uptake by upontheiruptake phytoplankton. waters surface ith themain focus onmass- fractionation during adsorption onFe-Mn during oxides adsorption fractionation +0.26‰ and +0.31‰, respectively, consistent and+0.31‰, respectively, +0.26‰ 62/58 ted marine Fe-Mn mightalso ted marineoxides havebeen are our data with results frompreviousstudies. withresults are ourdata lithogenic sedimentssu Ni valueof+0.37±Iron. 0.09‰onGibeon 60/58 et al Ni valuesmeasurediniron . 2006,2007,Moynier The metal-contaminated Themetal-contaminated Ni isotope determinations Niisotope independent Niisotope independent δ 60/58 ch asloessandNile δ Ni valueof 60/58 et al Ni values (see values Ni . 2009)and et al . Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted differentiation metallic ofthe core. Silicate Bulk the from differed may have afteritsaccretion NiisotopecompositionoftheEarth andthat segregation during core Earth’s Altogether, these results suggest that significan magmatic temperature °C),withthe metal (800 being enriched number inlowatomic isotopes. demonstrated anisotopicfracti Huh Recently, distinct phases(e.g.,solid-vapour, metal-silicate). vari interpretation, nickelisotope isotopicpool,whichwa acommon fractionation from meteorites followthe same mass-dependent line fractionation as terrestrial samples and indicate Moynierdependent Niisotopecompositions, suggestive lateral of heterogeneity inthe earlySolar System. Alternatively, based onmass- Ni of Inaddition, therange have alsooverlapped. bodies forthedifferen ofparent source regions Niisot fractionated independently mass- between Theoverlap chondrites. classes of different materialstothe precursor of region formed inarestricted Article (2011) andRegelous protosolar nebulaofmineralog mixing withinthe result of likely tobethe are mass-independent, are and chondrites,which etal As discussedby Regelous mass unit. ICP-MS solutionbatc the AesarNistandard thatMoynier etal however importanttonote in meteorites few and +0.80‰(only atomic numberisot enriched inhigh are also meteorites analysedMoynier by meteorites by Cameron et al et al et . (2008)suggestthateachironme et al . (2009)andSteeleet onation of at least -0.3‰ between at least-0.3‰ onation of withdifferent ical phases riations among iron meteorites ironmeteorites isotopicvariationsamong . (2008),theobserved the protosolar nebula aswas theprotosolarnebula et al ations in meteorites reflect ph reflect ations inmeteorites ope values of iron ope valuesofiron these datasets have negative havenegative these datasets . (2007) and Cameronetal . (2007)and Earth composition developed after the early theearly developed after composition Earth h No 066110910 and expressed theirresultsasper 066110910 andexpressed h No opes and have a range of a range opes andhave . (2007) report their isotopic ratios withrespectto reporttheirisotopicratios . (2007) et al et t classes of chondrites classes ofchondrites t t Ni isotope fractionations may have occurred isotopefractionationsmay occurred t Ni have isotopevaluesamongir . (2007)andCook . (2011),i.e.,0.24to0.36‰.Other meteorites and s homogenised in the solar nebula. Insolar nebula. this s homogenisedinthe nucleosynthetic origin. Steele teorite class had theirprotolith teorite classhad previously demonstrated forthe demonstrated previously ysicochemical reactions between ysicochemical reactions . (2009), including. (2009),chondrites, metallic andsilicatephasesat metallic et al Ni isotope values). ItNi isotopevalues). is chondrites suggeststhatthe chondrites et al values between +0.02‰ between values and iron meteoritesmightand iron . (2009) experimentally experimentally . (2009) . (2007) argue thatall . (2007)argue on meteoritesisalso on et al . materials, which show a range of range materials, whichshowa Ni isotopeco +0.05 ± herethe 0.05‰.We report nodules and organic matter-rich shales have positiveδ have shales nodules andorganic matter-rich Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted methods pres analytical new resultsforRMsand throughch processed small amountsofNiwere small butmeaningful fractionations ofmoreten than times the analytical precision evenwhen c ofNi large range a including sulfides,and of samplemeasuring matrices range a broad Ni is demonstrated thatfor processes, while negative fracti isotope fractionations systematic, are i.e.,fractionations positive characterise low-temperature theBSE value,and,more from significantly deviate andse magmatic (e.g., reservoirs (Gueguen Mn oxides and, potentially,processes bylow- abiotic producedby also 2009), buttheycan be are notanuniquebi Ni isotopefractionations value.This anearzero close tothatofBSE with otherwise, as least shownby the mineralised samples, komatiite have compositions Niisotope sulfides withnegative δ Article somevariationsinthe explain from -0.10to-1.03‰,indicatingthatfractionation samples ofkomatiites associated and Ni-sulfide mineralisation displaya range of inaqueous inorganic Niisotopefractionations crystals allowed the ustoestablish isotopi andultramafic and minerals altered fresh such igneous and rocks askomatiites basalts, olivine and clays, mantle-derived ofdeep-sea rockIn investigation thispaper, Conclusions et al et 60/58 . 2011). Therefore, the Ni isotope . 2011).Therefore,the otopes the double-spike correcti otopes thedouble-spike Ni values affectedNi isotope thecomposition of komatiites, which Ni isotopecompositionofnatural onations mark high-temperature onations markhigh-temperature dimentary rocks) relevant to the biogeochemical Ni cycle might might cycle Ni biogeochemical the to relevant rocks) dimentary δ temperature processes during co-precipitation ofNiwithFe- co-precipitation during processes temperature 60/58 Ni values more than 1‰. Interestingly,Ni valuesmorethan1‰. bothFe-Mn c composition of the Bulk Silicate Earth at at Earth Silicate Bulk ofthe c composition oncentrations. The method allowed us to measure ustomeasure Themethodallowed oncentrations. from silicatefrom rocks tometalliferous deposits, osignature, as was recently inferred (Cameron inferred recently aswas osignature, environments. We alsofoundthatbulkrock environments.We emistry and determined byMC-ICP-MS.emistry The anddetermined processes such as high-temperature magmatic magmatic as high-temperature such processes is an important finding since itemphasisesthat animportantfinding since is ented hereshould help ented mposition ofselected in high-temperature magmatic systems can can systems in high-temperature magmatic importantly, our results demonstratethatNi results importantly, our 60/58 Ni values,suggesting eitherbioticor on method is appropriate for on methodisappropriatefor composition of speci processes. Finally, we processes. have samples. Wesamples. infer that Ni-rich s of RMs andmafic s of geological reference geological reference to make Ni isotope to fic terrestrial fic terrestrial δ 60/58 δ 60/58 Ni values Ni = et al . Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted Mineralogy andGeochemistry, 55 Observati Molybdenum stableisotopes: Anbar A.D.(2004) cyclothems. Chemical Geology, 206, 289–318. faciesinco redox and behavior Trace-element Algeo T.J.andMaynard J.B.(2004) 55, 113–152. isotopes. Analytical methodsfornon-traditional F.Albarede andBeardB.(2004) References visiting scientist grant. by suppor Europôle Mer.Participation was AB ArticleISOMAR European Marie-Curie tothismanuscript.Thestud and corrections comments constructive for their thanked gratefully are Meisel Thomas editor andthe reviewers commentsonthefi thoughtful Sorensen fortheir Aust andWestern mineralisation fromCanada meteorite samples,FiorentiniMarco ofkomatiites andforsamples and associated Ni-sulfide for andYoanGerman Liorzou thankCéline We Acknowledgements materials. and planetary measurements morefreque and straightforward, more project (European Reintegr project(European , 429–454. , 429–454. ons, interpretations and directions. anddirections. ons, interpretations y was supported by funding from Ifremer, the y from funding supported by was re shales of Upper Pennsylvanian Kansas-type Kansas-type Pennsylvanian ofUpper shales re ralia. We thank Harry Elderfield and Jeffrey andJeffrey thankHarry Elderfield We ralia. ted by NSERC Discovery Grant and IFREMER and byGrant ted NSERCDiscovery laboratory assistance, Jean-Alix Barrat for iron Barrat for Jean-Alix assistance, laboratory Reviews inMineralogyandReviews Geochemistry, rst draftofthismanus ntlystudies utilised ofterrestrial infuture ation grant#FP7#247837),and cript. Two anonymous Twoanonymous cript. Reviews in Reviews Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted Mo intercalibration. tr IC1 contamination-prone (BATS) GEOTRACES (2012) M., RouxelO.,Sohrin Y., St M.,LacanF.,GallonFornaceK.,Gault-Ringold C.,Galer RadicA.,Rehkämper A.R., S., Boyle E.A.,JohnS.Abouchami W.,AdkinsJ.F 131–143. 90 Letters, Science Planetary and isotopesin Allendeinclusions.Earth Nickel andchromium Birck J.L.andLugmair G.W. (1988) soil. ofsour Stable CuandZn ratiosastracers isotope Bigalke M.,WeyerS.,Kobz Atmospheric sulfurinArchaean komatiite-hostednickel deposits. (2009) M.L., Fiorentini A.,BarleyM.E., Bekker Article 193,447–457. ScienceLetters, Planetary vari Natural mass-dependent Barling J.,ArnoldG.L. and AnbarA.D.(2001) Analyst, 127,76–82. of Mn-Fenodulesby Multielemental analysis Axelsson M.D.,Rodushkin I.,Ingri J.andOhlander B.(2002) 35, 717–746. Metal stable isotopes inpaleoceanography. Anbar A.D.andRouxelO.(2007) , 6801–6813. 74,6801–6813. Geochimica Acta, Cosmochimica et Limnology and Oceanography: Methods,10 Limnology ations intheisotopiccompositionofmolybdenum. a J. and Wilcke W. (2010) a J.andWilckeW.(2010) irling C.,Thompsonand ZhaoZ.C. Y. C.,VanceD.,Xue Annual Review ofEarth and Planetary Sciences, Rouxel O.J., Rumble D. and Beresford S.W. S.W. Beresford O.J.,Rumble D.and Rouxel ICP-MS: Optimisationofanalytical method. ces and transport of Cu and Zn in contaminated Zn incontaminated Cuand andtransportof ces ., Echegoyen-Sa ., ace element isotopes Cd, Fe, Pb, Zn, and Cu Fe,Pb, Cd, isotopes element ace Science, 326 nz Y., Ellwood M.,Flegalnz Y.,Ellwood , 653–665. , 1086–1089. Earth and , Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards AcceptedCook D.L.,WadhwaM., Janney P.E., Dauphas Science, 42,2067–2077. Mass-dependent fractionation ofnickel isotopes inmeteoritic andPlanetary metal. Meteoritics Cook D.L.,WadhwaM., ClaytonR.N.,Daupha doi: 10.1029/2007GL032431. Nickel isotopic anomalies introilite fromironmeteorites. 35, GeophysicalResearchLetters, M., Cook D.L.,ClaytonR.N.,Wadhwa MC-ICP-MS. by measured BCR 176,GSS-1,GXR-1,GXR-2,GSD-12,Nod-P-1, isotopicNatural cadmium variationsineight Cloquet C.,RouxelO.,CarignanJ.andLibourel G. (2005) Cosmochimica 73 Acta, isot fornickel A search Chen J.H.,Papanastassiou D.A.andWasserburg G.J. (2009) Article materials. isotopic and Chemical separation Chapman B.J.andWilkinson J.B.,Mason T.F.D.,Coles WeissD.J.,J.J. (2006) United the of Sciences Academy of National the of Proceedings stableisotopesofnickel. onthe A biomarkerbased C. andHouseC.H.(2009) Archer D., Cameron V.,Vance black shaleformation. carbon organic recent metalcontentof The trace Brumsack H.J.(2006) Geostandards andGeoanalytical 30 Research, Palaeogeography, Palaeoclimatology, Palaeoecology, 232,344–361. Palaeogeography, Palaeoclimatology, Palaeoecology, opic anomaliesinironme , 10944–10948. America, 106,10944–10948. Statesof , 1461–1471. Geostandards andGeoanalytical 29 Research, m five geological reference reference geological from five variations ofCuandZn Janney P.E. andDavisA.M.(2008) geological reference materials (NIST SRM2711, materials geological reference -rich sediments: Implications sediments: forCretaceous -rich teorites and s N.,Janney P.E. andDavisA.M. (2007) N., ClaytonR.N.andDavis A.M. (2006) Nod-A-1) and anthropogenic samples, andanthropogenic Nod-A-1) , 5–16. , 5–16. Geochimica et Geochimica chondrites. , 95–106. Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted Geophysical MonographSeries,188 of Anewtype mineralization: along processes ofhydrothermal Geodiversity Rouxel O.(2010) Cherkashov G., T.,Poroshina Semkova I.,Bohn M.,DonvalJ.P.,P. K., Henry Murphy and FouquetP., Etoubleau Y.,Cambon J.,Charlou J.L., Ondréas H.,Barriga F.J.A.S., Geochemistry, 43 Oxygen isotope ofbasaltic variations mantleand lavas upper rocks. Eiler J.M.(2001) Journal ISME The at 5000moffHawaii. Fe-o venting supports hydrothermal Ultra-diffuse Chan C.S.,TeboB.M., Staudi RouxelO.J.,Bach K.J.,Edwards GlazerB.T., double spike. Iron isotopesinnaturalcarbona ArticleDideriksen K.,andStipp S.L.S. BakerJ.A. (2006) 831–832. Mass spectrometryand natural va Dauphas N.and Rouxel O.(2006) results. measurement on ofstable-isotope-r expressi termsfor Guidelines andrecommended Coplen T.B.(2011) metal via multicollectorICP-MS. ofnon-mass-dependent High measurements precision Geochimica et Cosmochimica Acta, 70,118–132. Acta, etCosmochimicaGeochimica , 319–364. , 319–364. Rapid Communications in Mass Spectrometry, 25 oceanic Cu-Zn-Co-Au volcanogenic massive sulfidedeposit. volcanogenicmassive Cu-Zn-Co-Au oceanic te minerals determined by determined te minerals MC-ICP-MS withaFe-58-Fe-54 gel H. and Moyer C.L. (2011) gel H.and MoyerC.L.(2011) riations ofironisotopes. riations Analytical Chemistry, 78,8477–8484. , 444pp. , 1–11. the mid-atlantic ridge W., EmersonR.E., TonerB.M., D.,Davis xidizing bacteria and massive umberdeposition and massive bacteria xidizing effects innickel effects Mass Spectrometry Reviews, 25 Reviews, Mass Spectrometry Reviews inMineralogy and Reviews and ultramafic-hosted and ultramafic-hosted atio and gas-ratio atio andgas-ratio isotopes inmeteoritic isotopes , 2538–2560. , Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted me marine and ancient Ni biogeochemicalcyclethroughgeological time: Insightsvariations fromNiisotope inmodern Y. (2011) Gueguen B.,Rouxel O.,Ponzevera E.,Sorensen J.V., Toner B.M., Bekker A. andFouquet theNa Researchof of atomic ratiosand Absolute isotopicabundance Gramlich L.A.,BarnesI.L.and J.W.,Machlan PaulsenP.J. (1989) 18(SpecialIssue) Geostandards Newsletter, and sa 1994 compilationofworking values Govindaraju K. (1994) 847-877. Green Mount Keith,Agnew–Wiluna andgenesisof Controls ontheemplacement N.,Beresford M.,Rosengren Fiorentini Article 83–94. chondrites, ironmeteor Application ofMC-ICP-MS totheprecisedeter M.andHallidayFehrM.A., Rehkämper A.N.(2004) and MC-ICP-MS. Analytical Journalof Determination ofma Gall L.,Williams H.,SiebertC.andHallidayA.(2012) oceans. modern andancient investigation isotopicfrac ofnickel andexperimental Theoretical Fujii T.,MoynierF., N.and Abe Dauphas M. (2011) ss-dependent variations innickelis variations ss-dependent tallifereous deposits. tallifereous tional Institute of St Instituteof tional ites andsulfides. ites Geochimica Acta, et 75 Cosmochimica stone Belt, Australia. stone Western International Journal International Atomic Spectrometry, 27 S., Grguric B. and BarleyM.(2007) B.and Grguric S., mple description for 383 geostandards. for383 mple description AGU Fall 2011 AGU Meeting andards andTechnology,94 the MKD5 and Sarah’s Find Ni–Cu–PGE deposits, Find MKD5 andSarah’s the , 158pp. , 158pp. weight of a reference sample ofnickel. sample reference ofa weight mination oftelluriumisotope compositionsin otope compositionsusing doublespiking of Mass Spectrometry, 232 MassSpectrometry, of tionation in species relevant to speciesrelevant tionation in Mineralium Deposita, 42, Deposita, Mineralium , 137–145. , 137–145. , 469–482. , 469–482. , San Francisco, USA. USA. Francisco, , San , 347-356. 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(2012) Geophysics 11 Geosystems, archivesof as crusts Ferromanganese Xue Z. and HeinJ.R.(2010 M., Horner T.J.,SchönbächlerM.,Rehkämper deposits inZimbabweand nickel multiple-sulfur, using ironisotope data. Comparing orthomagmatic and hydrothermalmineralization models ofkomatiite-hosted nickel Deposita) Mineralium Hofmann A.,Bekker A.,Dirks P.,Gueguen B., , 1525–2027. )

zinc isotopiccompositionsby pl Mineralium Deposita, 47 Deposita, mineralization.Mineralium ed Ni–Cu–(PGE) deep water Cd isotopecompositions. water deep Earth andPlanetary , 388–406. , 388–406. Luck J.M. andAlbarèdeF. (2007) otopes between metal andsilicates:Constraints otopes betweenmetal om Loihi seamount and the island of Hawaii. om Loihi islandofHawaii. seamountandthe EOS TransactionsAGU, 90 EOS Rouxel O.J.andRumble D.(Submitted to Nielsen S.G., Williams H.,HallidayA.N., Science Letters, 63 Science Letters, asma-source massspectrometry. Deposita. Mineralium Geochemistry Geochemistry . , 167–176. , Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted deposits. ferromanganese Thallium isotope variations inseawater and hydrogenetic, diagenetic, and hydrothermal (2002) RehkämperFrank M.,M., Hein J.R.,PorcelliD., HallidayA.,Ingri J. andLiebetrau V. 272, 330–338. SolarSystem. intheearly Nickel isotopeheterogeneity Regelous M.,ElliottT. of metals andnotrace Nickel isotopes inironmeteorites-nucleosynthetic M., LatkoczyC.,HallidayA.N.andGünther Quitté G., D.(2006) Meier Site 1149.Proceedings ofthe Ocean Drilling Progr Plank T.,Ludden J.N.etal water samples by MC-ICP-MS. The precise and accuratedetermination ofthallium isotope compositions and concentrations for ArticleNielsen S.G., M.,BakerJ.andHallidayA.N.(2004) Rehkämper Canadian Journal of Earth Sciences,5 bodies ultramaficigneous Contrasting Archaean G.D. (1968) Naldrett A.J.andMason Mineralogist, 17 ofvolcan An example The Dundonalddeposit: Muir J.E.andComba C.D.A.(1979) Geochimica 71 Acta, et Cosmochimica Comparative stableisotopegeoche , 351–359. 60 Fe. Fe. and CoathC.D.(2008) Earth andPlanetary Earth and Planetary Science Letters, 242 Letters, Science Planetary and Earth . (2000) Chemical Geology, 204 chondrites and mistryNi, Cu,Zn, Feinchondrites of and , 4365–4379. , 4365–4379. , 111–143. , 111–143. ic-type nickel-sulfi ic-type in Dundonald and Clergue Townships,Ontario. inDundonaldandClergue , 65–81. 197,65–81. Letters, Science anomaliesinsulphide am, Partam,A: InitialReports, 185. Earth and Planetary Science Letters, Letters, Science Planetary and Earth , 109–124. de mineralization. , 16–25. , 16–25. s withnoeffects in iron meteorites. Canadian Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted (2011) Reinhard Scott C.T.,BekkerA., ocean. oftheProterozoic oxygenation thestepwise Tracing Scott C.,LyonsT.W.,BekkerA.,ShenY.,Po 277 environment. EarthandPlanetary ScienceLetters, isotopic cadmium Mass-dependent Galer andAbouchamiSchmitt S.J.G. (2009) A.D., W. ofthe New measurement Günther-Leopold I.,Weinreich T.,KnieKorschinek Faestermann K.,Rugel G., The doublespiketoolbox. Rudge J.F., B.C. Reynolds andBourdon B.(2009) ArticleEconomic Geologists, ,585–600. 99 fields ontheMid-AtlanticRidge. Copper isotopesystematics ofth Rouxel O.,Fouquetand Ludden Y. J.N.(2004) alteration crust during oceanic fractionation Iron isotope Rouxel O.,Dobbek N.,Ludden J.and Fouquet Y.(2003) Western Australia. komatiite-hosted MtKeithnick Reconstructionextensive ofan Archaean dacitic submarine volcaniccomplex associated withthe S.W.and PalichRosengren N.,CasR.A.F., Beresford B.M.(2008) Precambrian Research, 161 Research, Precambrian 60 Chemical Geology,265,420–431. Fe half-life. el deposit, Agnew-Wiluna Greenstone Belt,Yilgarn Greenstone el deposit,Agnew-Wiluna Craton, tchev sea-floor hydrothermal hydrothermal Loga sea-floor tchev and Lucky Strike,Rainbow, e Economic Geology andtheBullEconomic R. and Wohlmuther M. (2009) R. andWohlmutherM.(2009) C.T.,SchnetgerB.,Krapez B variations innaturew Physical Review Letters,103 Physical Review ulton S.W.,ChuX.and AnbarA.D.(2008) ulton , 34–52. G., Poutivtsev M., . Chemical Geology, 202,155–182. . Chemical ith emphasis on the marine ith emphasisonthe , 262–272. Nature, 452 ., Rumble D.andLyonsT.W. ., Rumble etin of etin of the Societyof , 072502. , 072502. Schumann D.,Kivel N., , 456-U5. , 456-U5. Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards 72 Bulletin, America Distribution ofthe elements insome major unitsof the Earth's crust. Turekian K.K. andWe 12–32. and metalsaspaleoredox Trace Tribovillard N.,AlgeoT.J.,Lyons 320, 1620–1622. durin Iron isotopefractionation Teng F.Z., DauphasN.andHelz R.T.(2008) spectrometry. Determination ofnatura Tanimizu M.andHirataT.(2006) Cosmochimica 75 Acta, Confirmation ofmass-independent Niis M.(2011) CoathC.D.andRegelous Steele R.C.J.,ElliottT., coupled plasma-massspectrometry. by isotopefractionation double-sp Determination ofmolybdenum T.F.and KramersSiebert C.,Nägler J.D.(2001) Letters, 63 conditionsbefore euxinic Late Archean Accepted ArticleNi isotopiccompositions inA Shimamura T.andLugmair (1983) G.W. , 177–188. , 177–188. Journal of Analytical Journal of , 175–192. l isotopic variationinnickelus l depohl K.H. (1961) , 7906–7925. llende andothe g magmatic inKilaueaIki differentiation LavaLake. paleoproductivity proxies: Anupdate. proxies: paleoproductivity Geochemistry Geophysics Geosystems, 2 T. and Riboulleau A.(2006) Atomic Spectrometry, 21 Atomic Spectrometry, the rise of atmospheric oxygen. atmosphericoxygen. theriseof otopic variability inironmeteorites. r meteorites. ing inductively coupled plasma-mass ing coupled inductively Earth andPlanetary Science , 1423–1426. , 1423–1426. ike multicollectorinductively Geological Society of Geological Societyof Chemical Geology, 232 Geology, 39,119–122. Geochimica et Geochimica , 1032. , 1032. Science, , precision of the determination of precision ofthedetermination onthe Ni concentration of toassesstheeffect NIST done measurements were SRM986.These Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards fresh dunite,deep-sea basalts, peridotite, claysolivine crystals. and forfurther Seedetails. text various igneous andvolca 0.05‰, determinedusing Cameron etal repr are terrestrial materials byclosedclaysandand symbols, deep-sea areliteratureboth extraterrestrial shown and for data the literature.RMs,koma Figure 5.Plotshowingisotopecompositionin Ni oneachmethod). fordetails text measured (see massbiaswhenNiisotoperatiosare ofinstrumental correction double-spike methodfor thetwomethods theconsistency of It indicates wasplottedonthefigure methods. The1:1lineartrend values obtainedw Figure 4.Comparisonof 2 of range the indicate lines Thedashed were processed. This figure themeasur showstheconsistency of standard This chemistry. through was processed Figure 2. forfurtherdetails). (see text grey band the by shown onthefigure <0.06‰ i.e.,2SE to obtain satisfactory precision, during wasnecessary analysis MC-ICP-MS (inngg valuesversusNiconcentration delta (2SE)of errors Figure 1.Plotoftwostandard captions Figure Geochemistry, 55 co The isotopegeochemistryand Young E.D.andGaly A. (2004) Acceptedof NIST SRM986,δ still correctly (seefordetails). black determined text The the line isotopic stands composition for deltavalues),wher andnon-zero bars (wide error f were samples (ratiosbelow0.6) Figure 3.PlotofNIST SRM986de de Ni of mean for the calculated Article

Isotopic composition of the mono-elemental standard solutionNiPlasmaCal®afterit standard Isotopiccomposition ofthemono-elemental . 2009,Steele , 197–230. , 197–230. 60/58 Ni =0.00‰. eralisation, mantle-derived rocks mineralisation,mantle-derived tiites andassociatedNi-sulfide esented by open symbols (Cook byopensymbols esented et al lta values of Ni PlasmaCal®. lta valuesof . 2011). The grey bar stands for the BSE bar standsforthe grey . 2011).The Ni isotopes. Nickel concentration in solution above 40 ng g insolutionabove40ng Niisotopes.Nickelconcentration smochemistry ofmagnesium. ound not to be correctly calculated by the double-spike method the by calculated ound nottobecorrectly lta values versus differentsp lta valuesversus ith the Cu-doping and double-spike correction correction Cu-dopingith theanddouble-spike , but moreimportantly useofthe itvalidates , but solution was run along with each sample batch. batch. eachsample with wasrunalong solution ed value even when diff valueeven ed eas over-spiked samples up to a ratio of 7 were toaratioof7were up over-spikedsamples eas ‰ of terrestrial sample ‰ ofterrestrial nic rocks and minerals such as altered and asaltered and mineralssuch nic rocks to show that data points followthisline. toshowthatdatapoints s (2 s et al = 0.07‰ for 24 datapoints) for =0.07‰ Reviews in Reviews Mineralogy and ike/sample ratios. Under-spiked ratios.Under-spiked ike/sample . 2007,Moynier erent amountsofnickel erent s from thisstudys from and δ 60/58 Ni valueof0.05± et al . 2007, -1 ) of -1 -1

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted Article

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted Article

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted Article

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted Article

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted Article

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted Article

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards

Acceptedδ60/58 Articleδ60/58 Ni (± 2SE, ‰) 2SE of Ni NIST SRM 986 (‰) 0.5 1.0 1.5 -0.05 0.05 0.15 -0.1 0 0.1 0 0 0 10 20 5 30 Ni Pcalsolutionbatch# Ni concentration (ngg 10 40 50 15 60 2 standarddeviation Mean deltaNivalueforPCal -1 ) 70 20 80 90 25

100

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards

Acceptedδ60/58 s Articleδ60/58 Ni (‰ ± 1 ) Cu-doping method Ni (‰ ± 2SE) -0.60 -0.40 -0.20 0.00 0.20 0.40 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 0.1 0.2 0.3 0.4 0.5 0.6 0 -0.60 0 0.5 δ -0.40 60/58 Ni (‰±2SE)double-spike method 1 -0.20 1.5 spike/sample ratio 1:1 Line 2 0.00 2.5 0.20 3 3.5 0.40

4 8

Association of Geoanalysts Association of Geoanalysts International © 2013 Research andGeoanalytical © 2013The Authors. Geostandards Accepted Article 1 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 -1 -1.2 Chondrites Serpentinite Dunite δ 60/58 Komatiites andassociatedNi-sulfidemineralisation Ni (‰) Olivine crystals Contaminated soil sediments Deep-sea surfaceclaysandlithogenic Altered andfreshbasalts Pacific Peridotite Iron meteorites Granite Iron Formation Coal Mn-nodules Devonian shale Devonian Atlantic 1.2