Monazite, lanthanide-rich glasses, and other trace elements in copper smelter slags: Constraints on critical metal behaviour in Si-Fe-rich melts

Monazite, lanthanide-rich glasses, and other trace elements in copper smelter slags: Constraints on critical metal behaviour in Si-Fe-rich melts | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Monazite, lanthanide-rich glasses, and other trace elements in copper smelter slags: Constraints on critical metal behaviour in Si-Fe-rich melts Hassan Gezzaz, Cristiana Ciobanu, Nigel Cook, kathy Ehrig, ashley slattery, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4792518/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 06 May, 2025 Read the published version in Mineralogy and Petrology → Version 1 posted 4 You are reading this latest preprint version Abstract Furnace slags are potential new sources of critical metals. We undertook a micron- to nanoscale study that addresses speciation, distribution and associations of phases in flash furnace (FF, oxidised) and electric furnace (EF, reduced) slags from the Olympic Dam mining-smelting-refinery operation. Results enable understanding of the behaviour and partitioning of critical metals between melt and cooling crystalline phases in a controlled smelter environment that mimics Fe-Si-rich systems in Nature. Melts at ~1300 °C result in slags that differ in the relative proportions of component phases. Both FF and EF slags comprise major magnetite and two, compositionally distinct Si-Fe-rich glasses (glass-1 and -2); fayalite is a main component of EF slag. Glass-1 is rich in REE+Y (4.5–5.4 wt%, Ce 2 O 3 +La 2 O 3 ) and contains dendritic monazite-(Ce). The EF slag crystallization sequence is: magnetite→fayalite+glass-1→monazite→glass-2. Immiscibility of REE in Si-Fe-rich melt is inferred from amorphous ‘monazite-like’ droplets. Chondrite-normalised fractionation patterns are defined by downwards-sloping LREE segments in both glasses. Partition coefficients are calculated for magnetite and fayalite relative to glasses. D REY for HREE exceeds those for LREE in all phases and fayalite has an order of magnetite higher D HREE than co-existing EF magnetite. Applying lattice strain models to experimental values show excellent fits for D HREE-model trends, even if lattice strain is not the sole factor controlling partitioning. Melt polymerisation, variable/unpredictable oxidation states, and constraints from specific crystallographic sites, also impact on observed trends. This study demonstrates that clues to element behaviour in the deep Earth are available from metallurgical plants. Copper smelter slags melt-solid partitioning rare earth elements monazite Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Full Text Additional Declarations No competing interests reported. Supplementary Files Gezzazetal.SMTable3LAICPMSdata.xlsx Gezzazetal.SMTables1and2.docx HG3SMTextandfigure.docx Cite Share Download PDF Status: Published Journal Publication published 06 May, 2025 Read the published version in Mineralogy and Petrology → Version 1 posted Editorial decision: Revision requested 28 Jul, 2024 Editor assigned by journal 28 Jul, 2024 Submission checks completed at journal 24 Jul, 2024 First submitted to journal 24 Jul, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4792518","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":332736755,"identity":"7c44389d-3c4b-4548-a090-115e25761165","order_by":0,"name":"Hassan Gezzaz","email":"data:image/png;base64,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","orcid":"","institution":"University of Adelaide","correspondingAuthor":true,"prefix":"","firstName":"Hassan","middleName":"","lastName":"Gezzaz","suffix":""},{"id":332736756,"identity":"4dbe8d72-b022-4d3f-9391-f8d7e7dc8ede","order_by":1,"name":"Cristiana Ciobanu","email":"","orcid":"","institution":"University of Adelaide","correspondingAuthor":false,"prefix":"","firstName":"Cristiana","middleName":"","lastName":"Ciobanu","suffix":""},{"id":332736757,"identity":"1a2c3f22-3987-4822-aca9-5453dec873de","order_by":2,"name":"Nigel Cook","email":"","orcid":"","institution":"University of Adelaide","correspondingAuthor":false,"prefix":"","firstName":"Nigel","middleName":"","lastName":"Cook","suffix":""},{"id":332736758,"identity":"5c0db098-2923-4d26-a29e-4f0268fc7279","order_by":3,"name":"kathy Ehrig","email":"","orcid":"","institution":"University of Adelaide","correspondingAuthor":false,"prefix":"","firstName":"kathy","middleName":"","lastName":"Ehrig","suffix":""},{"id":332736759,"identity":"d00d2de8-85fa-4d4a-a4d8-fc18245b5acd","order_by":4,"name":"ashley slattery","email":"","orcid":"","institution":"University of Adelaide","correspondingAuthor":false,"prefix":"","firstName":"ashley","middleName":"","lastName":"slattery","suffix":""},{"id":332736760,"identity":"f226ba22-eba1-4345-9203-89eec879684a","order_by":5,"name":"benjamin wade","email":"","orcid":"","institution":"University of Adelaide","correspondingAuthor":false,"prefix":"","firstName":"benjamin","middleName":"","lastName":"wade","suffix":""},{"id":332736761,"identity":"134ade5c-4cc9-4d3a-b50e-207c842a4ff8","order_by":6,"name":"sarah gilbert","email":"","orcid":"","institution":"University of Adelaide","correspondingAuthor":false,"prefix":"","firstName":"sarah","middleName":"","lastName":"gilbert","suffix":""},{"id":332736762,"identity":"30f0a94a-30bf-4829-8513-8756e8a841c3","order_by":7,"name":"yuri camporodriguez","email":"","orcid":"","institution":"University of Adelaide","correspondingAuthor":false,"prefix":"","firstName":"yuri","middleName":"","lastName":"camporodriguez","suffix":""}],"badges":[],"createdAt":"2024-07-24 05:26:36","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4792518/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4792518/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00710-025-00897-2","type":"published","date":"2025-05-06T15:57:16+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":62944325,"identity":"b51e1e63-f0c2-4488-ae92-a330610adbd1","added_by":"auto","created_at":"2024-08-21 10:05:56","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":24957161,"visible":true,"origin":"","legend":"\u003cp\u003ePetrographic aspects of the two slags. Automated mineralogy and BSE maps of FF (\u003cstrong\u003ea\u003c/strong\u003e) and EF (\u003cstrong\u003eb\u003c/strong\u003e) slags with calculated compositions using AM phase proportions and EPMA data from Table 1. BSE images show associations and textures of main components in FF (\u003cstrong\u003ec,d\u003c/strong\u003e) and FF (\u003cstrong\u003ee.f\u003c/strong\u003e) slags. Cu‒metallic copper; Fa‒fayalite; gl1,2‒glasses-1, -2; Mag‒magnetite\u003c/p\u003e","description":"","filename":"Figure1HG.png","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/6eb416a0bf8a5b0f7ff8af5d.png"},{"id":62942916,"identity":"076d9cf1-4f2c-4990-abd3-43261440f668","added_by":"auto","created_at":"2024-08-21 09:49:56","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":6870253,"visible":true,"origin":"","legend":"\u003cp\u003eAspects of glass-1 (gl1) containing monazite (Mnz) and amorphous REE-P-droplets in FF slag. BSE images \u003cstrong\u003e(a-c\u003c/strong\u003e) showing filaments of Mnz and mottling with REE-P-droplets in gl1. (\u003cstrong\u003ed\u003c/strong\u003e) HAADF image and EDS STEM maps of amorphous REE-P-droplets in glass-1. Cu‒copper; Del‒delafossite; Mag‒magnetite\u003c/p\u003e","description":"","filename":"Figure2HG.png","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/459915c152f31f034f1e1ec6.png"},{"id":62942921,"identity":"cb697523-568a-4c1b-9191-96fde15dc57c","added_by":"auto","created_at":"2024-08-21 09:49:56","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":16771481,"visible":true,"origin":"","legend":"\u003cp\u003eMonazite (Mnz) and amorphous REE-P-droplets in EF slag. (\u003cstrong\u003ea-c\u003c/strong\u003e) BSE images showing sub-micron filaments of monazite in glass-1, often crosscutting boundaries between glass and fayalite (Fa). (\u003cstrong\u003ed\u003c/strong\u003e) HAADF image and EDS STEM maps of symplectites between glass-1 and fayalite. (\u003cstrong\u003ee\u003c/strong\u003e) EDS STEM overlay maps showing nanoparticles of monazite and chalcocite (Cc) along the Fa-glass-1 contact (circle marked on (\u003cstrong\u003ed\u003c/strong\u003e). (\u003cstrong\u003ef, g\u003c/strong\u003e) BSE images showing monazite filaments within glass-1 with various styles of mottling. (\u003cstrong\u003eh,i\u003c/strong\u003e) Image and maps showing nanosized REE-P-droplets (arrowed) in glass-1. gl2‒glass2; Mag‒magnetite\u003c/p\u003e","description":"","filename":"Figure3HG.png","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/e72821d9b87c036c392c1329.png"},{"id":62943613,"identity":"c5047859-a762-4e2f-bfea-8e52e6a3fbde","added_by":"auto","created_at":"2024-08-21 09:57:56","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":9388256,"visible":true,"origin":"","legend":"\u003cp\u003eMorphological variation of µm- and nanosized monazite (Mnz) shown as BSE images (\u003cstrong\u003ea-c\u003c/strong\u003e) and EDS STEM maps (\u003cstrong\u003ed-i\u003c/strong\u003e). This comprises single or branched dendrites formed by agglomerations of Mnz nanoparticles (NPs) (\u003cstrong\u003ea,b,d,e,g\u003c/strong\u003e), clusters/arrays of euhedral grains (\u003cstrong\u003ec,h\u003c/strong\u003e) or bladed symplectites with glass-1 (\u003cstrong\u003ef\u003c/strong\u003e). Note uraninite (Urn) NPs within the symplectites. (\u003cstrong\u003ei\u003c/strong\u003e) Image and EDS STEM maps of rare apatite-Ce (Ap) at contact between delafossite (Del), glass-1 (gl1) and SiO\u003csub\u003e2\u003c/sub\u003e. Crs‒cristobalite; Fa‒fayalite; Mag‒magnetite\u003c/p\u003e","description":"","filename":"Figure4HG.png","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/c6ca8dd92c91f9d62edec937.png"},{"id":62943627,"identity":"7b08dc10-6151-48b6-9fd6-0d51fec45215","added_by":"auto","created_at":"2024-08-21 09:57:59","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":16928621,"visible":true,"origin":"","legend":"\u003cp\u003e(\u003cstrong\u003ea\u003c/strong\u003e) Nanoparticles of monazite (Mnz) and molybdenite (Mol) at contact between glass-1 (gl1) and fayalite (Fa). (\u003cstrong\u003eb\u003c/strong\u003e) Euhedral grain of monazite showing homogenous composition for main elements. (\u003cstrong\u003ec-e\u003c/strong\u003e) High-resolution images, corresponding fast Fourier transform (FFT) patterns, crystal-models and STEM simulations of monazite on zone axes as labelled.\u003c/p\u003e","description":"","filename":"Figure5HG.png","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/e039d3aa19f7932b6c9b5808.png"},{"id":62942928,"identity":"7401bb23-40b2-4906-937f-f6263c41a0cc","added_by":"auto","created_at":"2024-08-21 09:49:59","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":16466549,"visible":true,"origin":"","legend":"\u003cp\u003eBoxplots showing trace elements in all analysed phases as labelled from FF (\u003cstrong\u003ea,b\u003c/strong\u003e) and EF (\u003cstrong\u003ec,d\u003c/strong\u003e) slag. Elements are categorized as spinel group, lithophile elements, REY and other incompatible elements, and a grouping of ‘other metals’ (Cr, As, Sb, Sn, Ga, and Ge)\u003c/p\u003e","description":"","filename":"Figure6HG.png","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/35aa0ad0b5fa6e70b2638e27.png"},{"id":62943615,"identity":"3eca798f-8a85-4d9a-bf66-73f005be16f3","added_by":"auto","created_at":"2024-08-21 09:57:57","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":5520748,"visible":true,"origin":"","legend":"\u003cp\u003e(a-f) Binary plots of LA-ICPMS data showing trends between elements in different phases from EF slag. (a) P vs 𝛴REE (b) Nb vs 𝛴REE, (c) Yb vs 𝛴REE, (d) Ni vs Co, (e) V vs Ti, (f) Mn vs Mg. (g) P vs 𝛴REE in glass-1 and -2 in slags as labelled. (h) Ni vs Co in FF and EF magnetite. (i) Mn vs Zn in FF and EF magnetite\u003c/p\u003e","description":"","filename":"Figure7HG.png","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/b27efa9cdbd254c4886c06dc.png"},{"id":62943626,"identity":"46ea4b41-f546-4445-9ea0-ec348b976ef4","added_by":"auto","created_at":"2024-08-21 09:57:58","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":10557317,"visible":true,"origin":"","legend":"\u003cp\u003e(a,b) Chondrite-normalized fractionalization patterns in glasses from slag types as labelled. Note comparable trends between glasses for each slag type, albeit one order of magnitude lower and with a pronounced positive Eu-anomaly in glass-2. (c) Time-resolved LA-ICP-MS depth profiles of selected elements, as labelled, in inclusion-free glass-1 from FF and EF slags. (d) Time-resolved LA-ICPMS depth profiles of selected elements in glass-1 from FF slag containing monazite inclusions. (e-h) Chondrite-normalised fractionation patterns for magnetite and fayalite as labelled. Note patterns in (e) and (f) are for magnetite with \u0026lt;100 ppm and \u0026gt;100 ppm ΣREY, respectively. Patterns in (g) and (h) are for fayalite with \u0026lt;500 ppm and \u0026gt;500 ppm ΣREY, respectively\u003c/p\u003e","description":"","filename":"Figure8HG.png","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/a5005ec70c21ee6fadf4d052.png"},{"id":62942927,"identity":"73d6e094-5b67-45ef-af4b-4b0bb1c34676","added_by":"auto","created_at":"2024-08-21 09:49:58","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":6597029,"visible":true,"origin":"","legend":"\u003cp\u003eRepresentative time-resolved depth LA-ICP-MS profiles for phases as labelled. Numbers in brackets represent element concentrations in ppm. Note flat, relatively smooth signals for all elements except LREE (La, Ce) in (\u003cstrong\u003ec\u003c/strong\u003e, \u003cstrong\u003eb,\u003c/strong\u003e \u003cstrong\u003ed\u003c/strong\u003e, and \u003cstrong\u003eh\u003c/strong\u003e). Irregular signals indicate the presence of subsurface inclusions of monazite and/or glass in magnetite and fayalite. Note correlation between Nb and REE in fayalite from (\u003cstrong\u003eh\u003c/strong\u003e)\u003c/p\u003e","description":"","filename":"Figure9HG.png","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/9c6129728c9f7afbd8fc771c.png"},{"id":62942930,"identity":"99a84070-1b8a-4fcc-87e1-8176bce0fc53","added_by":"auto","created_at":"2024-08-21 09:49:59","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":4473986,"visible":true,"origin":"","legend":"\u003cp\u003eExperimental partition coefficients (D\u003csub\u003ei-exp\u003c/sub\u003e) of elements of interest in phases as labelled. \u003cstrong\u003e(a-c\u003c/strong\u003e) REY, (\u003cstrong\u003ed-f\u003c/strong\u003e) divalent elements, (\u003cstrong\u003eg-i\u003c/strong\u003e) Heterovalent HFSE elements. Experimental partition coefficients for plotted elements and comparison with literature data are listed beneath each. References: 1−Dygert et al. (2020); 2−Wijbrans et al. (2015); 3−\u003csup\u003e \u003c/sup\u003eSievwright et al. (2020) \u0026nbsp;\u003c/p\u003e","description":"","filename":"Figure10HG.png","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/82ff9fed96866cf334a55f54.png"},{"id":62942924,"identity":"ee075c53-2d89-4bc3-8991-3a5f1fe8a017","added_by":"auto","created_at":"2024-08-21 09:49:58","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":3787013,"visible":true,"origin":"","legend":"\u003cp\u003eExperimental D\u003csub\u003ei\u003c/sub\u003e values (blue circles) fitted along parabolas (orange line) obtained by lattice strain model for REY (\u003cstrong\u003ea-c\u003c/strong\u003e), divalent elements (\u003cstrong\u003ed-f\u003c/strong\u003e) and tetravalent elements (\u003cstrong\u003eg-i\u003c/strong\u003e). Parabola fitting parameters, fractions of Ni and Co in tetrahedral sites (T) and fractions of V\u003csup\u003e4+\u003c/sup\u003e in octahedral sites (M) are listed below each plot. Red circles in (\u003cstrong\u003ea\u003c/strong\u003e) and (\u003cstrong\u003ec\u003c/strong\u003e) are V\u003csup\u003e3+\u003c/sup\u003e values calculated using fractions obtained from parabola fitting. Fa‒fayalite; Mag‒magnetite\u003c/p\u003e","description":"","filename":"Figure11HG.png","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/aa2f8f619cc727fce39702c4.png"},{"id":82537572,"identity":"f58c204a-8285-4bb6-90a0-d83bb2c62b4c","added_by":"auto","created_at":"2025-05-12 16:08:49","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":14855603,"visible":true,"origin":"","legend":"","description":"","filename":"2JulyHassanpaper3MP.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1_covered_2bb2042d-8160-494e-9954-acc8144654b3.pdf"},{"id":62943611,"identity":"84127c08-918e-43dc-829c-1ee784fd1f40","added_by":"auto","created_at":"2024-08-21 09:57:56","extension":"xlsx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":28269,"visible":true,"origin":"","legend":"","description":"","filename":"Gezzazetal.SMTable3LAICPMSdata.xlsx","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/c068acf759e34b86a6da4498.xlsx"},{"id":62942918,"identity":"8860c91d-a9a6-4d35-8af3-a28c80492860","added_by":"auto","created_at":"2024-08-21 09:49:56","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":217910,"visible":true,"origin":"","legend":"","description":"","filename":"Gezzazetal.SMTables1and2.docx","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/f5a0854b4f268e675260b80f.docx"},{"id":62942922,"identity":"22b64ff5-e38b-4fcd-8ba4-ac403c60aad4","added_by":"auto","created_at":"2024-08-21 09:49:57","extension":"docx","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":630933,"visible":true,"origin":"","legend":"","description":"","filename":"HG3SMTextandfigure.docx","url":"https://assets-eu.researchsquare.com/files/rs-4792518/v1/1a99d6e6e259930fe9551ce1.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Monazite, lanthanide-rich glasses, and other trace elements in copper smelter slags: Constraints on critical metal behaviour in Si-Fe-rich melts","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"mineralogy-and-petrology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mipe","sideBox":"Learn more about [Mineralogy and Petrology](http://link.springer.com/journal/710)","snPcode":"710","submissionUrl":"https://submission.nature.com/new-submission/710/3","title":"Mineralogy and Petrology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Copper smelter slags ,melt-solid partitioning ,rare earth elements ,monazite","lastPublishedDoi":"10.21203/rs.3.rs-4792518/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4792518/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eFurnace slags are potential new sources of critical metals. We undertook a micron- to nanoscale study that addresses speciation, distribution and associations of phases in flash furnace (FF, oxidised) and electric furnace (EF, reduced) slags from the Olympic Dam mining-smelting-refinery operation. Results enable understanding of the behaviour and partitioning of critical metals between melt and cooling crystalline phases in a controlled smelter environment that mimics Fe-Si-rich systems in Nature. Melts at ~1300 °C result in slags that differ in the relative proportions of component phases. Both FF and EF slags comprise major magnetite and two, compositionally distinct Si-Fe-rich glasses (glass-1 and -2); fayalite is a main component of EF slag. Glass-1 is rich in REE+Y (4.5–5.4 wt%, Ce\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e+La\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e) and contains dendritic monazite-(Ce). The EF slag crystallization sequence is: magnetite→fayalite+glass-1→monazite→glass-2. Immiscibility of REE in Si-Fe-rich melt is inferred from amorphous ‘monazite-like’ droplets. Chondrite-normalised fractionation patterns are defined by downwards-sloping LREE segments in both glasses. Partition coefficients are calculated for magnetite and fayalite relative to glasses. D\u003csub\u003eREY\u003c/sub\u003e\u0026nbsp;for HREE exceeds those for LREE in all phases and fayalite has an order of magnetite higher D\u003csub\u003eHREE\u003c/sub\u003e\u0026nbsp;than co-existing EF magnetite. Applying lattice strain models to experimental values show excellent fits for D\u003csub\u003eHREE-model\u003c/sub\u003e\u0026nbsp;trends, even if lattice strain is not the sole factor controlling partitioning. Melt polymerisation, variable/unpredictable oxidation states, and constraints from specific crystallographic sites, also impact on observed trends. This study demonstrates that clues to element behaviour in the deep Earth are available from metallurgical plants.\u003c/p\u003e","manuscriptTitle":"Monazite, lanthanide-rich glasses, and other trace elements in copper smelter slags: Constraints on critical metal behaviour in Si-Fe-rich melts","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-08-21 09:49:51","doi":"10.21203/rs.3.rs-4792518/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-07-28T11:04:26+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-07-28T09:26:59+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-07-25T00:47:13+00:00","index":"","fulltext":""},{"type":"submitted","content":"Mineralogy and Petrology","date":"2024-07-24T05:25:20+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"mineralogy-and-petrology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mipe","sideBox":"Learn more about [Mineralogy and Petrology](http://link.springer.com/journal/710)","snPcode":"710","submissionUrl":"https://submission.nature.com/new-submission/710/3","title":"Mineralogy and Petrology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"665926a8-4586-4072-83a8-0b95e9b1d47b","owner":[],"postedDate":"August 21st, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-05-12T16:00:22+00:00","versionOfRecord":{"articleIdentity":"rs-4792518","link":"https://doi.org/10.1007/s00710-025-00897-2","journal":{"identity":"mineralogy-and-petrology","isVorOnly":false,"title":"Mineralogy and Petrology"},"publishedOn":"2025-05-06 15:57:16","publishedOnDateReadable":"May 6th, 2025"},"versionCreatedAt":"2024-08-21 09:49:51","video":"","vorDoi":"10.1007/s00710-025-00897-2","vorDoiUrl":"https://doi.org/10.1007/s00710-025-00897-2","workflowStages":[]},"version":"v1","identity":"rs-4792518","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4792518","identity":"rs-4792518","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}