[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-156954-105":59,"doc-detail-156954-en":131},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":124,"head_meta":126,"extra_data":128,"updated_unix":130},105,"en","rare-earth-elements-mineral-profile-definitions-mineralogy-and-deposits","Rare Earth Elements - Mineral profile: Definitions, mineralogy and deposits","","Rare earth elements (REE) are defined as a group of 17 chemically similar metallic elements, comprising the 15 lanthanides plus scandium and yttrium. The profile explains why the term “rare earth” is a misnomer, contrasts crustal abundance across individual REE, and summarizes the light/heavy and sometimes middle grouping. It also outlines key characteristics such as trivalency exceptions, ionic/radiation-driven substitution in crystal structures, and relevant physical properties including melting point trends and magnetic behavior. The document then surveys REE-bearing mineral types and how REE occur in minerals rather than as native metals.",{"@graph":69,"@context":123},[70,84,106],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":40,"@type":76,"position":81},"https://docshare.wps.com/document/research-report/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/rare-earth-elements-mineral-profile-definitions-mineralogy-and-deposits/156954/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/rare-earth-elements-mineral-profile-definitions-mineralogy-and-deposits/156954.png","ImageObject",300,407,{"name":92,"@type":93},"Gloria","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-29","2026-08-29",true,{"@type":102,"interactionType":103,"userInteractionCount":105},"InteractionCounter",{"@type":104},"ViewAction",21,{"@type":107,"mainEntity":108},"FAQPage",[109,115,119],{"name":110,"@type":111,"acceptedAnswer":112},"What are rare earth elements (REE) and which elements are included?","Question",{"text":113,"@type":114},"REE are a group of 17 chemically similar metallic elements: the 15 lanthanides plus scandium and yttrium. They span atomic numbers 57 to 71 for the lanthanides.","Answer",{"name":116,"@type":111,"acceptedAnswer":117},"Why is the term “rare earth” considered a misnomer?",{"text":118,"@type":114},"Although the minerals they were originally isolated from were rare, REE are relatively plentiful in the Earth’s crust. Overall crustal abundance is reported as 9.2 ppm, with large variation by element.",{"name":120,"@type":111,"acceptedAnswer":121},"Where do REE occur in nature and in what mineral types?",{"text":122,"@type":114},"REE do not occur naturally as metallic elements. They occur in many mineral types—such as halides, carbonates, oxides, phosphates and silicates—mainly hosted by rock-forming minerals where they substitute for major ions.","https://schema.org",{"og:url":83,"og:type":125,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":127,"canonical":83},"index,follow",{"doc_id":129,"site_id":62},156954,1787970264,{"code":4,"msg":5,"data":132},{"doc_id":129,"user_id":133,"nickname":92,"user_avatar":134,"doc_module":4,"category_id":39,"category_name":40,"doc_title":65,"doc_description":67,"doc_content":135,"file_id":136,"file_url":137,"file_type":138,"file_size":139,"view_count":105,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":140,"language":141,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":142,"faqs":143,"seo_title":144,"seo_description":67,"update_tm":130,"read_time":145,"preview_page_count":4},2336474459895,"https://ap-avatar.wpscdn.com/avatar/22000baeef7a5ed0655?x-image-process=image/resize,m_fixed,w_180,h_180&k=1786071322749376916","Rare Earth Elements  \nM i ne ra ls UK  \nCen t re fo r sus t a inab le mi n era l development  \nM inera l profile  \nDefinitions, mineralogy and deposits  \nDefinitions and characteristics  \nThe rare earth elements (REE) (sometimes referred to asthe rare earth metals) are a group of 17 chemically similar metallic elements, including the 15 lanthanides, scandium and yttrium. The lanthanides are elements spanning atomic numbers 57 (lanthanum, La) to 71 (lutetium, Lu)(Table 1) . The lanthanides all occur in nature, although promethium1, the rarest, only occurs in trace quantities in natural materials as it has no long-lived or stable isotopes (Castor and Hedrick, 2006) . Scandium and yttrium are considered REE as they have similar chemical and physical properties. Separation of the individual REE was a difficult challenge for chemists in the 18th and 19th centuries, and consequently it was not until the 20th century that they were all identified. On account of their chemical similarity the REE can very easily substitute for one another making refinement to pure metal difficult.  \nThe term rare earth is a misnomer arising from the rarity of the minerals from which they were originally isolated (Figures 1 and 2) . In contrast REEs are relatively plentiful in the Earth’s crust having an overall crustal abundance of 9.2 ppm (Rudnick et al. 2003) . The crustal abundance of individual REE varies widely, from cerium the most abundant at 43 ppm (exceeding other important metals including copper—27 ppm and lead—11 ppm) to 0.28 ppm for thulium (Taylor and McLennan, 1985; Rudnick et al. 2003) .  \nThe lanthanides are commonly divided into: lower atomic weight elements, lanthanum through to europium, referred to as the light rare earth elements (LREE) and the heavy rare earth elements (HREE)—gadolinium through to lutetium and yttrium (Table 1) . Yttrium is usually grouped with the HREE because of its chemical similarity. The division is somewhat arbitrary and the term middle REE (MREE) is sometimes used to refer to those elements between europium to dysprosium (Samson and Wood, 2004) . The relative abundance of the REE varies  \nUnless otherwise stated, copyright of materials contained in this report are vested in NERC. BGS © NERC 2011. All rights reserved.  \n1 Promethium: is a radioactive element.  \nNovember 2011  \nTable 1 Selected properties of the REE. Compiled from Gupta and Krishnamurthy (2005).  \nFigure 1 Elongate prismatic fergusonite in an open cavity associated with albite and quartz, Arran, Scotland. Photograph: Fergus MacTaggart, BGS © NERC.  \nRare Earth Elements  \nMineral  \nAeschynite-(Ce)  \nAllanite-(Ce)  \nApatite  \nBastnäsite-(Ce)  \nBrannerite  \nBritholite-(Ce)  \nEudialyte  \nEuxenite-(Y)  \nFergusonite-(Ce)  \nGadolinite-(Ce)  \nKainosite-(Y)  \nLoparite  \nMonazite-(Ce)  \nParisite-(Ce)  \nXenotime  \nYttrocerite  \nHuanghoite-(Ce)  \nCebaite-(Ce)  \nFlorencite-(Ce)  \nSynchysite-(Ce)  \nSamarskite-(Y)  \nKnopite  \nFormula  \n(Ce,Ca,Fe,Th)(Ti,Nb)2(O,OH)6.(Ce,Ca,Y)2(Al,Fe3+)3(SiO4)3OH. Ca5(PO4)3(F, Cl,OH)  \n(Ce,La)(CO3)F  \n(U,Ca,Y, Ce)(Ti,Fe)2O6 (Ce,Ca)5(SiO4, PO4)3(OH,F) Na4(Ca,Ce)2(Fe2+, Mn,Y) ZrSi8O22(OH,Cl)2(?) .  \n(Y. Ca. Ce,U,Th)(Nb,Ta,Ti)2O6 (Ce,La,Nd)NbO4  \n(Ce,La,Nd,Y)2Fe2+Be2Si2O10. Ca2(Y, Ce)2Si4O12CO3. H2O.(Ce,La,Na,Ca,Sr)(Ti,Nb)O3 (Ce,La,Nd,Th)PO4  \nCa(Ce,La)2(CO3)3F2.  \nYPO4.  \n(Ca,Ce,Y, La)F3. nH2O. BaCe(CO3)2F.  \nBa3Ce2(CO3)5F2.  \nCeAl3(PO4)2(OH)6.  \nCa(Ce,LA)(CO3)2F.  \n(Y, Ce,U,Fe3+)3(Nb,Ta,Ti)5O16.(CaTi,Ce2)O3  \nApproximate REO %  \n32  \n38  \n19  \n75  \n9  \n32  \n9  \n24  \n53  \n60  \n38  \n30  \n65  \n61  \n61  \n53  \n39  \n32  \n32  \n51  \n24  \nna  \nTable 2 A selection ofREE-bearing minerals. Mineral formulae sourced from Clark (1993) and estimates of REO content based on Webmineral composition, with the exception of apatite (Casterand Hedrick 2006). Where the mineral name is followed by brackets the formula is for the specific chemical variant of the mineral identified. Note one or more other chemical variants, in which the dominant element","cbCaicxxqktFkZr9","https://ap.wps.com/l/cbCaicxxqktFkZr9","pdf",4804940,54,"English","# Definitions, mineralogy and deposits\n## Definitions and characteristics\n## Mineralogy","[{\"question\":\"What are rare earth elements (REE) and which elements are included?\",\"answer\":\"REE are a group of 17 chemically similar metallic elements: the 15 lanthanides plus scandium and yttrium. They span atomic numbers 57 to 71 for the lanthanides.\"},{\"question\":\"Why is the term “rare earth” considered a misnomer?\",\"answer\":\"Although the minerals they were originally isolated from were rare, REE are relatively plentiful in the Earth’s crust. Overall crustal abundance is reported as 9.2 ppm, with large variation by element.\"},{\"question\":\"Where do REE occur in nature and in what mineral types?\",\"answer\":\"REE do not occur naturally as metallic elements. They occur in many mineral types—such as halides, carbonates, oxides, phosphates and silicates—mainly hosted by rock-forming minerals where they substitute for major ions.\"}]","Rare Earth Elements - Mineral profile: Definitions, mineralogy and deposits | PDF",136]