[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"minerals:one:1036":3},{"id":4,"longid":5,"guid":6,"name":7,"shortcode_ima":8,"entrytype":9,"entrytype_text":10,"varietyof":11,"synid":11,"polytypeof":11,"groupid":12,"weighting":13,"nolocadd":14,"blacklisted":14,"mindat_formula":15,"mindat_formula_note":11,"ima_formula":16,"elements":17,"sigelements":21,"key_elements":22,"impurities":23,"cim":24,"ima_status":25,"ima_notes":11,"ima_history":11,"approval_year":11,"publication_year":28,"discovery_year":29,"strunz10ed1":30,"strunz10ed2":31,"strunz10ed3":31,"strunz10ed4":32,"dana8ed1":33,"dana8ed2":34,"dana8ed3":35,"dana8ed4":35,"csystem":36,"cclass":37,"spacegroup":38,"spacegroupset":39,"a":40,"b":41,"c":41,"alpha":41,"beta":41,"gamma":41,"aerror":11,"berror":11,"cerror":11,"alphaerror":11,"betaerror":11,"gammaerror":11,"va3":11,"z":42,"csmetamict":14,"commentcrystal":11,"twinning":43,"tranglide":11,"parting":44,"epitaxidescription":11,"morphology":45,"tlform":11,"hmin":46,"hmax":46,"hardtype":11,"vhnmin":47,"vhnmax":48,"vhnerror":11,"vhng":49,"vhns":11,"commenthard":11,"dmeas":50,"dmeas2":51,"dcalc":52,"dmeaserror":11,"dcalcerror":11,"commentdense":11,"lustre":11,"lustretype":53,"commentluster":11,"diapheny":54,"streak":55,"colour":56,"commentcolor":11,"colors":57,"streak_colors":60,"luminescence":11,"uv":61,"cleavage":11,"cleavagetype":62,"fracturetype":63,"tenacity":64,"commentbreak":65,"opticaltype":66,"opticalsign":11,"opticalalpha":41,"opticalalpha2":41,"opticalalphaerror":11,"opticalbeta":41,"opticalbeta2":41,"opticalbetaerror":11,"opticalgamma":41,"opticalgamma2":41,"opticalgammaerror":11,"opticalomega":41,"opticalomega2":41,"opticalomegaerror":11,"opticalepsilon":41,"opticalepsilon2":41,"opticalepsilonerror":11,"opticaln":67,"opticaln2":68,"opticalnerror":11,"optical2vcalc":41,"optical2vcalc2":41,"optical2vcalcerror":11,"optical2vmeasured":41,"optical2vmeasured2":41,"optical2vmeasurederror":11,"rimin":11,"rimax":11,"opticaldispersion":11,"opticalpleochroism":69,"opticalpleochorismdesc":11,"opticalbirefringence":70,"opticalcomments":11,"opticalcolour":71,"opticalinternal":72,"opticaltropic":66,"opticalanisotropism":11,"opticalbireflectance":11,"opticalextinction":11,"opticalr":73,"specdispm":11,"ir":11,"electrical":11,"magnetism":11,"thermalbehaviour":11,"other":74,"industrial":75,"occurrence":11,"otheroccurrence":76,"type_specimen_store":11,"description_short":77,"aboutname":78,"rock_parent":11,"rock_parent2":11,"rock_root":9,"rock_bgs_code":11,"meteoritical_code":11,"updttime":79,"reviewed_at":11,"variety_of":11,"varieties":80,"group_members":97,"associates":261,"confused_with":324,"type_localities":337,"occurrence_total":344,"citations":345,"images":498,"structures":820,"synonyms":849,"language_names":877,"wikidata_qid":1082,"texts":1083},1036,"1:1:1036:4","7d202627-c431-4cb2-a077-2c1ebe843d1e","Chromite","Chr",0,"mineral",null,52933,6944,false,"Fe\u003Csup>2+\u003C\u002Fsup>Cr\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","Fe\u003Csup>2+\u003C\u002Fsup>Cr\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",[18,19,20],"Cr","Fe","O",[18,19,20],[18],"Mg,Mn,Zn,Al,Ti,","7.14.12",[26,27],"APPROVED","GRANDFATHERED",1845,"1845","4","B","05","7","2","3","Isometric",32,222,"Fd-3m","8.344","0",8,"On {111}","Parting may develop along {111}","Octahedral crystals uncommon, modified by {001} at times. Rarely, crystals may show small dodecahedral faces, etc. Usually massive, fine granular to compact.",5.5,"1278","1456",100,"4.5","4.8","5.12","Resinous,Greasy,Metallic,Sub-Metallic,Dull","Translucent,Opaque","Brown","Black",[58,59],"black","brown",[59],"Not fluorescent in UV","None Observed","Irregular\u002FUneven,Hackly,Sub-Conchoidal","brittle","Broken surfaces frequently have an angular granulated appearance.","Isotropic","2.08","2.16","Non-pleochroic","0.0","Grey-white with brownish tint.","Brownish red","(13.2) 400,\r\n(13.1) 420,\r\n(13.0) 440,\r\n(12.8) 460,\r\n(12.6) 480,\r\n(12.4) 500,\r\n(12.2) 520,\r\n(12.0) 540,\r\n(11.9) 560,\r\n(11.8) 580,\r\n(11.7) 600,\r\n(11.7) 620,\r\n(11.6) 640,\r\n(11.6) 660,\r\n(11.6) 680,\r\n(11.6) 700","Some are weakly magnetic due to zones of magnetite composition, etc.","Major ore source for chromium.","As a cumulate mineral layer in ultramafic igneous rocks, in peridotites. As placer deposits. Common in meteorites except carbonaceous chondrites.","Chromite is the most important chromium ore mineral.\r\nIt forms a complete solid solution series with many other members of the group, eg. in the Chromite-Hercynite Series, Chromite-Spinel Series, Chromite-Magnetite Series and the Chromite-Magnesiochrom...","Chromite was named in 1845 by Wilhelm Haidinger in allusion to its composition. The species was originally named \u003Cem>fer chromate alumine\u003C\u002Fem> by Louis Nicolas Vauquelin in 1798. Vauquelin was the discoverer of the element chromium.","2026-04-12 19:03:22",[81,86,90,94],{"id":82,"name":83,"entrytype":84,"csystem":11,"ima_formula":11,"mindat_formula":85,"hmin":11,"hmax":11,"dmeas":41,"dcalc":11,"primary_image_id":11},8083,"Aluminian Chromite",2,"Fe(Cr,Al)\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",{"id":87,"name":88,"entrytype":84,"csystem":11,"ima_formula":11,"mindat_formula":89,"hmin":11,"hmax":11,"dmeas":41,"dcalc":11,"primary_image_id":11},10656,"Ferrian Chromite","Fe\u003Csup>2+\u003C\u002Fsup>(Cr,Fe\u003Csup>3+\u003C\u002Fsup>)\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",{"id":91,"name":92,"entrytype":84,"csystem":11,"ima_formula":11,"mindat_formula":93,"hmin":11,"hmax":11,"dmeas":11,"dcalc":11,"primary_image_id":11},43494,"Ferrichromite","Fe\u003Csup>2+\u003C\u002Fsup>(Cr\u003Csup>3+\u003C\u002Fsup>,Fe\u003Csup>3+\u003C\u002Fsup>)\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",{"id":95,"name":96,"entrytype":84,"csystem":11,"ima_formula":11,"mindat_formula":15,"hmin":11,"hmax":11,"dmeas":41,"dcalc":41,"primary_image_id":11},11369,"Titanium-bearing Chromite",[98,102,107,115,121,127,133,142,149,155,160,167,173,181,188,193,200,205,212,219,225,232,238,243,250,255],{"id":99,"name":100,"entrytype":9,"csystem":36,"ima_formula":101,"mindat_formula":101,"hmin":11,"hmax":11,"dmeas":11,"dcalc":11,"primary_image_id":11},56040,"Chihmingite","NiAl\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",{"id":103,"name":104,"entrytype":9,"csystem":36,"ima_formula":105,"mindat_formula":105,"hmin":106,"hmax":106,"dmeas":41,"dcalc":41,"primary_image_id":11},1101,"Cochromite","CoCr\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",7,{"id":108,"name":109,"entrytype":9,"csystem":36,"ima_formula":110,"mindat_formula":110,"hmin":111,"hmax":112,"dmeas":113,"dcalc":114,"primary_image_id":11},1142,"Coulsonite","Fe\u003Csup>2+\u003C\u002Fsup>V\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",4.5,5,"5.17","5.15",{"id":116,"name":117,"entrytype":9,"csystem":36,"ima_formula":118,"mindat_formula":118,"hmin":119,"hmax":119,"dmeas":41,"dcalc":120,"primary_image_id":11},1192,"Cuprospinel","Cu\u003Csup>2+\u003C\u002Fsup>Fe\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",6.5,"5.25",{"id":122,"name":123,"entrytype":9,"csystem":36,"ima_formula":124,"mindat_formula":124,"hmin":119,"hmax":106,"dmeas":11,"dcalc":125,"primary_image_id":126},52860,"Dellagiustaite","V\u003Csup>2+\u003C\u002Fsup>Al\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","4.6",6995,{"id":128,"name":129,"entrytype":9,"csystem":130,"ima_formula":131,"mindat_formula":131,"hmin":11,"hmax":11,"dmeas":11,"dcalc":132,"primary_image_id":11},47933,"Deltalumite","Tetragonal","(Al\u003Csub>0.67\u003C\u002Fsub>◻\u003Csub>0.33\u003C\u002Fsub>)Al\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","3.663",{"id":134,"name":135,"entrytype":9,"csystem":36,"ima_formula":136,"mindat_formula":137,"hmin":46,"hmax":138,"dmeas":139,"dcalc":140,"primary_image_id":141},1598,"Franklinite","ZnFe\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","Zn\u003Csup>2+\u003C\u002Fsup>Fe\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",6,"5.07","5.163",29732,{"id":143,"name":144,"entrytype":9,"csystem":36,"ima_formula":145,"mindat_formula":145,"hmin":146,"hmax":42,"dmeas":41,"dcalc":147,"primary_image_id":148},1632,"Gahnite","ZnAl\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",7.5,"4.62",29734,{"id":150,"name":151,"entrytype":9,"csystem":36,"ima_formula":152,"mindat_formula":152,"hmin":146,"hmax":146,"dmeas":41,"dcalc":153,"primary_image_id":154},1639,"Galaxite","Mn\u003Csup>2+\u003C\u002Fsup>Al\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","4.03",9569,{"id":156,"name":157,"entrytype":9,"csystem":36,"ima_formula":158,"mindat_formula":158,"hmin":138,"hmax":119,"dmeas":11,"dcalc":159,"primary_image_id":11},52593,"Guite","Co\u003Csup>2+\u003C\u002Fsup>Co\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","6.003",{"id":161,"name":162,"entrytype":9,"csystem":130,"ima_formula":163,"mindat_formula":163,"hmin":46,"hmax":46,"dmeas":164,"dcalc":165,"primary_image_id":166},1832,"Hausmannite","Mn\u003Csup>2+\u003C\u002Fsup>Mn\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","4.83","4.84",10932,{"id":168,"name":169,"entrytype":9,"csystem":36,"ima_formula":170,"mindat_formula":170,"hmin":146,"hmax":146,"dmeas":41,"dcalc":171,"primary_image_id":172},1875,"Hercynite","Fe\u003Csup>2+\u003C\u002Fsup>Al\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","4.39",11200,{"id":174,"name":175,"entrytype":9,"csystem":130,"ima_formula":176,"mindat_formula":177,"hmin":138,"hmax":138,"dmeas":178,"dcalc":179,"primary_image_id":180},1883,"Hetaerolite","ZnMn\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","ZnMn\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","5.18","5.23",29867,{"id":182,"name":183,"entrytype":9,"csystem":36,"ima_formula":184,"mindat_formula":184,"hmin":46,"hmax":119,"dmeas":185,"dcalc":186,"primary_image_id":187},2061,"Jacobsite","Mn\u003Csup>2+\u003C\u002Fsup>Fe\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","4.76","5.03",61304,{"id":189,"name":190,"entrytype":9,"csystem":36,"ima_formula":191,"mindat_formula":191,"hmin":138,"hmax":138,"dmeas":41,"dcalc":41,"primary_image_id":192},2533,"Maghemite","(Fe\u003Csup>3+\u003C\u002Fsup>\u003Csub>0.67\u003C\u002Fsub>◻\u003Csub>0.33\u003C\u002Fsub>)Fe\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",14994,{"id":194,"name":195,"entrytype":9,"csystem":36,"ima_formula":196,"mindat_formula":196,"hmin":46,"hmax":46,"dmeas":197,"dcalc":198,"primary_image_id":199},2493,"Magnesiochromite","MgCr\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","4.1","4.43",15049,{"id":201,"name":202,"entrytype":9,"csystem":36,"ima_formula":203,"mindat_formula":203,"hmin":119,"hmax":119,"dmeas":41,"dcalc":204,"primary_image_id":11},2476,"Magnesiocoulsonite","MgV\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","4.31",{"id":206,"name":207,"entrytype":9,"csystem":36,"ima_formula":208,"mindat_formula":208,"hmin":46,"hmax":119,"dmeas":209,"dcalc":210,"primary_image_id":211},2501,"Magnesioferrite","MgFe\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","4.56","4.51",15064,{"id":213,"name":214,"entrytype":9,"csystem":36,"ima_formula":215,"mindat_formula":215,"hmin":46,"hmax":119,"dmeas":216,"dcalc":217,"primary_image_id":218},2538,"Magnetite","Fe\u003Csup>2+\u003C\u002Fsup>Fe\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","5.175","5.2",65576,{"id":220,"name":221,"entrytype":9,"csystem":36,"ima_formula":222,"mindat_formula":222,"hmin":46,"hmax":46,"dmeas":41,"dcalc":223,"primary_image_id":224},2475,"Manganochromite","Mn\u003Csup>2+\u003C\u002Fsup>Cr\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","4.88",15322,{"id":226,"name":227,"entrytype":9,"csystem":36,"ima_formula":228,"mindat_formula":228,"hmin":146,"hmax":42,"dmeas":229,"dcalc":230,"primary_image_id":231},3729,"Spinel","MgAl\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","3.6","3.578",80269,{"id":233,"name":234,"entrytype":9,"csystem":36,"ima_formula":235,"mindat_formula":235,"hmin":11,"hmax":11,"dmeas":11,"dcalc":236,"primary_image_id":237},53041,"Thermaerogenite","CuAl\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","4.87",4384,{"id":239,"name":240,"entrytype":9,"csystem":36,"ima_formula":241,"mindat_formula":242,"hmin":11,"hmax":11,"dmeas":41,"dcalc":41,"primary_image_id":11},29152,"Titanomaghemite","(Ti\u003Csub>0.5\u003C\u002Fsub>◻\u003Csub>0.5\u003C\u002Fsub>)Fe\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","(Ti\u003Csup>4+\u003C\u002Fsup>\u003Csub>0.5\u003C\u002Fsub>◻\u003Csub>0.5\u003C\u002Fsub>)Fe\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",{"id":244,"name":245,"entrytype":9,"csystem":36,"ima_formula":246,"mindat_formula":247,"hmin":112,"hmax":112,"dmeas":248,"dcalc":217,"primary_image_id":249},4012,"Trevorite","NiFe\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","Ni\u003Csup>2+\u003C\u002Fsup>Fe\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","5.164",17562,{"id":251,"name":252,"entrytype":9,"csystem":36,"ima_formula":253,"mindat_formula":253,"hmin":119,"hmax":119,"dmeas":41,"dcalc":41,"primary_image_id":254},4217,"Vuorelainenite","Mn\u003Csup>2+\u003C\u002Fsup>V\u003Csup>3+\u003C\u002Fsup>\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>",27672,{"id":256,"name":257,"entrytype":9,"csystem":36,"ima_formula":258,"mindat_formula":258,"hmin":46,"hmax":138,"dmeas":41,"dcalc":259,"primary_image_id":260},4412,"Zincochromite","ZnCr\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","5.434",28795,[262,269,278,283,290,297,303,309,316],{"id":263,"name":264,"entrytype":9,"csystem":36,"ima_formula":265,"mindat_formula":265,"hmin":112,"hmax":112,"dmeas":266,"dcalc":267,"primary_image_id":268},439,"Awaruite","Ni\u003Csub>3\u003C\u002Fsub>Fe","7.8","7.74",2385,{"id":270,"name":271,"entrytype":9,"csystem":272,"ima_formula":273,"mindat_formula":273,"hmin":274,"hmax":275,"dmeas":41,"dcalc":276,"primary_image_id":277},1666,"Geerite","Trigonal","Cu\u003Csub>8\u003C\u002Fsub>S\u003Csub>5\u003C\u002Fsub>",3.5,4,"5.61",9714,{"id":279,"name":280,"entrytype":9,"csystem":281,"ima_formula":282,"mindat_formula":282,"hmin":11,"hmax":11,"dmeas":11,"dcalc":11,"primary_image_id":11},40647,"Icosahedrite","Icosahedral","Al\u003Csub>63\u003C\u002Fsub>Cu\u003Csub>24\u003C\u002Fsub>Fe\u003Csub>13\u003C\u002Fsub>",{"id":284,"name":285,"entrytype":9,"csystem":286,"ima_formula":287,"mindat_formula":287,"hmin":146,"hmax":146,"dmeas":41,"dcalc":288,"primary_image_id":289},2164,"Kashinite","Orthorhombic","Ir\u003Csub>2\u003C\u002Fsub>S\u003Csub>3\u003C\u002Fsub>","9.10",8004,{"id":291,"name":292,"entrytype":9,"csystem":36,"ima_formula":293,"mindat_formula":293,"hmin":106,"hmax":146,"dmeas":294,"dcalc":295,"primary_image_id":296},2344,"Laurite","RuS\u003Csub>2\u003C\u002Fsub>","6.43","6.39",14084,{"id":298,"name":299,"entrytype":9,"csystem":272,"ima_formula":300,"mindat_formula":301,"hmin":146,"hmax":146,"dmeas":11,"dcalc":302,"primary_image_id":11},42725,"Oxy-chromium-dravite","NaCr\u003Csub>3\u003C\u002Fsub>(Cr\u003Csub>4\u003C\u002Fsub>Mg\u003Csub>2\u003C\u002Fsub>)(Si\u003Csub>6\u003C\u002Fsub>O\u003Csub>18\u003C\u002Fsub>)(BO\u003Csub>3\u003C\u002Fsub>)\u003Csub>3\u003C\u002Fsub>(OH)\u003Csub>3\u003C\u002Fsub>O","NaCr\u003Csub>3\u003C\u002Fsub>(Cr\u003Csub>4\u003C\u002Fsub>Mg\u003Csub>2\u003C\u002Fsub>)(Si\u003Csub>6\u003C\u002Fsub>O\u003Csub>18\u003C\u002Fsub>)(BO\u003Csub>3\u003C\u002Fsub>)\u003Csub>3\u003C\u002Fsub>(OH)\u003Csub>3\u003C\u002Fsub>O ","3.299",{"id":304,"name":305,"entrytype":9,"csystem":306,"ima_formula":307,"mindat_formula":307,"hmin":138,"hmax":106,"dmeas":41,"dcalc":41,"primary_image_id":308},3482,"Rutheniridosmine","Hexagonal","(Ir,Os,Ru)",21322,{"id":310,"name":311,"entrytype":9,"csystem":130,"ima_formula":312,"mindat_formula":313,"hmin":111,"hmax":111,"dmeas":41,"dcalc":314,"primary_image_id":315},3920,"Tetra-auricupride","CuAu","AuCu","14.67",2331,{"id":317,"name":318,"entrytype":9,"csystem":36,"ima_formula":319,"mindat_formula":320,"hmin":274,"hmax":274,"dmeas":321,"dcalc":322,"primary_image_id":323},4388,"Zaratite","Ni\u003Csub>3\u003C\u002Fsub>(CO\u003Csub>3\u003C\u002Fsub>)(OH)\u003Csub>4\u003C\u002Fsub> · 4H\u003Csub>2\u003C\u002Fsub>O","Ni\u003Csub>3\u003C\u002Fsub>(CO\u003Csub>3\u003C\u002Fsub>)(OH)\u003Csub>4\u003C\u002Fsub>·4H\u003Csub>2\u003C\u002Fsub>O ?","2.57","2.67",28663,[325,330,331,332],{"id":326,"name":327,"entrytype":9,"csystem":286,"ima_formula":328,"mindat_formula":328,"hmin":11,"hmax":11,"dmeas":11,"dcalc":329,"primary_image_id":11},51979,"Chenmingite","FeCr\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>","5.27",{"id":194,"name":195,"entrytype":9,"csystem":36,"ima_formula":196,"mindat_formula":196,"hmin":46,"hmax":46,"dmeas":197,"dcalc":198,"primary_image_id":199},{"id":213,"name":214,"entrytype":9,"csystem":36,"ima_formula":215,"mindat_formula":215,"hmin":46,"hmax":119,"dmeas":216,"dcalc":217,"primary_image_id":218},{"id":333,"name":334,"entrytype":9,"csystem":286,"ima_formula":328,"mindat_formula":16,"hmin":11,"hmax":11,"dmeas":335,"dcalc":336,"primary_image_id":11},35792,"Xieite","5.63","5.342",[338],{"id":339,"txt":340,"latitude":341,"longitude":342,"country":343},16082,"Carrade de Cavalaire, Cavalaire-sur-Mer, Draguignan, Var, Provence-Alpes-Côte d'Azur, France",43.1988752,6.5450497,"France",4080,[346,350,354,358,363,368,373,377,381,386,390,394,399,404,408,413,417,421,425,430,434,439,443,447,452,457,461,466,470,474,479,484,489,493],{"id":347,"year":348,"html":349,"doi":11},16105783,1800,"Pontier, C. (1800): Bulletin Société Philomatique Paris: 55: 57.",{"id":351,"year":352,"html":353,"doi":11},16105784,1920,"Simpson (1920): Mineralogical Magazine: 19: 99 (as Beresofite).",{"id":355,"year":356,"html":357,"doi":11},1118651,1944,"Palache, Charles, Berman, Harry, Frondel, Clifford (1944) \u003Ci>The System of Mineralogy\u003C\u002Fi> (7th ed.) Vol. 1 - Elements, Sulfides, Sulfosalts, Oxides. John Wiley and Sons, New York.",{"id":359,"year":360,"html":361,"doi":362},336907,1967,"Ramdohr, Paul (1967) Chromite and chromite chondrules in meteorites—I. \u003Ci>Geochimica et Cosmochimica Acta\u003C\u002Fi>,  31 (10) 1961-1967 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1016\u002F0016-7037(67)90135-4'>doi:10.1016\u002F0016-7037(67)90135-4\u003C\u002Fa>","10.1016\u002F0016-7037(67)90135-4",{"id":364,"year":365,"html":366,"doi":367},16596174,1969,"Ramdohr, Paul (1969) \u003Ci>The Ore Minerals and their Intergrowths\u003C\u002Fi>. Pergamon Press, Oxford. 1174pp. \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1016\u002Fc2013-0-10027-x'>doi:10.1016\u002Fc2013-0-10027-x\u003C\u002Fa>","10.1016\u002Fc2013-0-10027-x",{"id":369,"year":370,"html":371,"doi":372},338441,1975,"Wasilewski, P., Virgo, D., Ulmer, G.C., Schwerer, F.C. (1975) Magnetochemical characterization of Fe(FexCr2−x)O4 spinels. \u003Ci>Geochimica et Cosmochimica Acta\u003C\u002Fi>,  39 (6) 889-902 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1016\u002F0016-7037(75)90035-6'>doi:10.1016\u002F0016-7037(75)90035-6\u003C\u002Fa>","10.1016\u002F0016-7037(75)90035-6",{"id":374,"year":370,"html":375,"doi":376},338445,"Basu, Asish R, MacGregor, Ian D (1975) Chromite spinels from ultramafic xenoliths. \u003Ci>Geochimica et Cosmochimica Acta\u003C\u002Fi>,  39 (6) 937-945 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1016\u002F0016-7037(75)90039-3'>doi:10.1016\u002F0016-7037(75)90039-3\u003C\u002Fa>","10.1016\u002F0016-7037(75)90039-3",{"id":378,"year":370,"html":379,"doi":380},338448,"Bliss, N.W., MacLean, W.H. (1975) The paragenesis of zoned chromite from central Manitoba. \u003Ci>Geochimica et Cosmochimica Acta\u003C\u002Fi>,  39 (6) 973-990 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1016\u002F0016-7037(75)90042-3'>doi:10.1016\u002F0016-7037(75)90042-3\u003C\u002Fa>","10.1016\u002F0016-7037(75)90042-3",{"id":382,"year":383,"html":384,"doi":385},16105787,1976,"DA SILVA, E. G., ABRAS, A., SETTE CAMARA, A. O. R. (1976) Mössbauer effect study of cation distribution in natural chromites. \u003Ci>Le Journal de Physique Colloques\u003C\u002Fi>,  37 (C6). C6-783-C6-785 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1051\u002Fjphyscol:19766165'>doi:10.1051\u002Fjphyscol:19766165\u003C\u002Fa>","10.1051\u002Fjphyscol:19766165",{"id":387,"year":383,"html":388,"doi":389},16105788,"FATSEAS, G. A., DORMANN, J. L., BLANCHARD, H. (1976) STUDY OF THE Fe\u003Csup>3+\u003C\u002Fsup>\u002FFe\u003Csup>2+\u003C\u002Fsup> RATIO IN NATURAL CHROMITES (Fe\u003Csub>x\u003C\u002Fsub>, Mg\u003Csub>1-x\u003C\u002Fsub>) (Cr\u003Csub>1-y-z\u003C\u002Fsub>, Fe\u003Csub>y\u003C\u002Fsub>, Al\u003Csub>z\u003C\u002Fsub>)O\u003Csub>4\u003C\u002Fsub>. \u003Ci>Le Journal de Physique Colloques\u003C\u002Fi>,  37 (C6). C6-787-C6-792 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1051\u002Fjphyscol:19766166'>doi:10.1051\u002Fjphyscol:19766166\u003C\u002Fa>","10.1051\u002Fjphyscol:19766166",{"id":391,"year":392,"html":393,"doi":11},16105789,1980,"Da Silva, E.G., Abras, A., and Speziali, L. (1980) Mössbauer effect study of cation distribution in natural chromites of Brazilian and Philippine origin. Journal of Applied Physics: 12: 389-392.",{"id":395,"year":396,"html":397,"doi":398},75186,1981,"Osborne, Margery D., Fleet, Michael E., Michael Bancroft, G. (1981) Fe2+-Fe3+ ordering in chromite and Cr-bearing spinels. \u003Ci>Contributions to Mineralogy and Petrology\u003C\u002Fi>,  77 (3). 251-255 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1007\u002Fbf00373539'>doi:10.1007\u002Fbf00373539\u003C\u002Fa>","10.1007\u002Fbf00373539",{"id":400,"year":401,"html":402,"doi":403},267629,1991,"Leblanc, Marc, Ceuleneer, Georges (1991) Chromite crystallization in a multicellular magma flow: Evidence from a chromitite dike in the Oman ophiolite. \u003Ci>Lithos\u003C\u002Fi>,  27 (4) 231-257 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1016\u002F0024-4937(91)90002-3'>doi:10.1016\u002F0024-4937(91)90002-3\u003C\u002Fa>","10.1016\u002F0024-4937(91)90002-3",{"id":405,"year":401,"html":406,"doi":407},1764,"Mitra, Sachinath, Pal, Tapan, Pal, Taraknath (1991) Petrogenetic implication of the Mössbauer hyperfine parameters of Fe\u003Csup>3+\u003C\u002Fsup>-chromites from Sukinda (India) ultramafites. \u003Ci>Mineralogical Magazine\u003C\u002Fi>,  55 (381) 535-542 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1180\u002Fminmag.1991.055.381.06'>doi:10.1180\u002Fminmag.1991.055.381.06\u003C\u002Fa> \u003Ca target='_blank' href='https:\u002F\u002Frruff.info\u002Fdoclib\u002FMinMag\u002FVolume_55\u002F55-381-535.pdf' class='refpdflink'>\u003C\u002Fa>","10.1180\u002Fminmag.1991.055.381.06",{"id":409,"year":410,"html":411,"doi":412},152054,1992,"Chen, Y.L., Xu, B.F., Chen, J.G., Ge, Y.Y. (1992) Fe2+-Fe3+ ordered distribution in chromite spinels. \u003Ci>Physics and Chemistry of Minerals\u003C\u002Fi>,  19 (4). 255-259 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1007\u002Fbf00202316'>doi:10.1007\u002Fbf00202316\u003C\u002Fa>","10.1007\u002Fbf00202316",{"id":414,"year":415,"html":416,"doi":11},16296375,1994,"Roeder, P.L. (1994) Chromite: from the fiery rain of chondrules to the Kilauea Iki lava lake. Canadian Mineralogist, 32, 729-746.",{"id":418,"year":415,"html":419,"doi":420},155939,"Zhou, M. F., Robinson, P. T., Bai, W. J. (1994) Formation of podiform chromitites by melt\u002Frock interaction in the upper mantle. \u003Ci>Mineralium Deposita\u003C\u002Fi>,  29 (1) 98-101 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1007\u002Fbf03326400'>doi:10.1007\u002Fbf03326400\u003C\u002Fa>","10.1007\u002Fbf03326400",{"id":422,"year":415,"html":423,"doi":424},227813,"Stowe, C. W. (1994) Compositions and tectonic settings of chromite deposits through time. \u003Ci>Economic Geology\u003C\u002Fi>,  89 (3) 528-546 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.2113\u002Fgsecongeo.89.3.528'>doi:10.2113\u002Fgsecongeo.89.3.528\u003C\u002Fa>","10.2113\u002Fgsecongeo.89.3.528",{"id":426,"year":427,"html":428,"doi":429},227590,1995,"Rollinson, Hugh (1995) Composition and tectonic settings of chromite deposits through time; discussion. \u003Ci>Economic Geology\u003C\u002Fi>,  90 (7) 2091-2092 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.2113\u002Fgsecongeo.90.7.2091'>doi:10.2113\u002Fgsecongeo.90.7.2091\u003C\u002Fa>","10.2113\u002Fgsecongeo.90.7.2091",{"id":431,"year":427,"html":432,"doi":433},227591,"Stowe, C. W. (1995) Compositions and tectonic settings of chromite deposits through time; reply. \u003Ci>Economic Geology\u003C\u002Fi>,  90 (7) 2092-2094 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.2113\u002Fgsecongeo.90.7.2092'>doi:10.2113\u002Fgsecongeo.90.7.2092\u003C\u002Fa>","10.2113\u002Fgsecongeo.90.7.2092",{"id":435,"year":436,"html":437,"doi":438},179064,1996,"ZHOU, MEI-FU, ROBINSON, PAUL T., MALPAS, JOHN, LI, ZIJIN (1996) Podiform Chromitites in the Luobusa Ophiolite (Southern Tibet): Implications for Melt-Rock Interaction and Chromite Segregation in the Upper Mantle. \u003Ci>Journal of Petrology\u003C\u002Fi>,  37 (1) 3-21 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1093\u002Fpetrology\u002F37.1.3'>doi:10.1093\u002Fpetrology\u002F37.1.3\u003C\u002Fa>","10.1093\u002Fpetrology\u002F37.1.3",{"id":440,"year":441,"html":442,"doi":11},16105799,1997,"Zhou, Mei-Fu and Robnson, P.T. (1997) Origin and tectonic environment of podiform chromite deposits. Economic geology: 92: 259-262.",{"id":444,"year":441,"html":445,"doi":446},202,"Figueiras, Jorge, Waerenborgh, Joāo C. (1997) Fully oxidized chromite in the Serra Alta (South Portugal) quartzites: chemical and structural characterization and geological implications. \u003Ci>Mineralogical Magazine\u003C\u002Fi>,  61 (408) 627-638 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1180\u002Fminmag.1997.061.408.02'>doi:10.1180\u002Fminmag.1997.061.408.02\u003C\u002Fa> \u003Ca target='_blank' href='https:\u002F\u002Frruff.info\u002Fdoclib\u002FMinMag\u002FVolume_61\u002F61-408-627.pdf' class='refpdflink'>\u003C\u002Fa>","10.1180\u002Fminmag.1997.061.408.02",{"id":448,"year":449,"html":450,"doi":451},347249,1998,"Zhou, Mei-Fu, Sun, Min, Keays, Reid R., Kerrich, Robert W. (1998) Controls on Platinum-Group Elemental Distributions of Podiform Chromitites: A Case Study of High-Cr and High-Al Chromitites from Chinese Orogenic Belts. \u003Ci>Geochimica et Cosmochimica Acta\u003C\u002Fi>,  62 (4) 677-688 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1016\u002Fs0016-7037(97)00382-7'>doi:10.1016\u002Fs0016-7037(97)00382-7\u003C\u002Fa>","10.1016\u002Fs0016-7037(97)00382-7",{"id":453,"year":454,"html":455,"doi":456},9848954,2000,"Salviulo, G., Carbonin, S., Della Giusta, A. (2000) Powder and Single-Crystal X-Ray Structural Refinement on a Natural Chromite: Dependence of Site Occupancies on Experimental Strategies. \u003Ci>Materials Science Forum\u003C\u002Fi>, 321. 46-53 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.4028\u002Fwww.scientific.net\u002Fmsf.321-324.46'>doi:10.4028\u002Fwww.scientific.net\u002Fmsf.321-324.46\u003C\u002Fa>","10.4028\u002Fwww.scientific.net\u002Fmsf.321-324.46",{"id":458,"year":454,"html":459,"doi":460},178603,"BARNES, STEPHEN J. (2000) Chromite in Komatiites. II. Modification during Greenschist to Mid-Amphibolite Facies Metamorphism. \u003Ci>Journal of Petrology\u003C\u002Fi>,  41 (3). 387-409 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1093\u002Fpetrology\u002F41.3.387'>doi:10.1093\u002Fpetrology\u002F41.3.387\u003C\u002Fa>","10.1093\u002Fpetrology\u002F41.3.387",{"id":462,"year":463,"html":464,"doi":465},394955,2004,"Papike, J.J., Karner, J.M., Shearer, C.K. (2004) Comparative planetary mineralogy: V\u002F(Cr + Al) systematics in chromite as an indicator of relative oxygen fugacity. \u003Ci>American Mineralogist\u003C\u002Fi>,  89 (10) 1557-1560 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.2138\u002Fam-2004-1027'>doi:10.2138\u002Fam-2004-1027\u003C\u002Fa>","10.2138\u002Fam-2004-1027",{"id":467,"year":468,"html":469,"doi":11},16963691,2007,"(2007) Chromite. \u003Ci>Handbook of Mineralogy\u003C\u002Fi>. Mineralogical Society of America \u003Ca target='_blank' href='https:\u002F\u002Fwww.handbookofmineralogy.org\u002Fpdfs\u002Fchromite.pdf' class='refpdflink'>\u003C\u002Fa>",{"id":471,"year":472,"html":473,"doi":11},16105804,2012,"Mosier, D.L., Singer, D.A., Moring, B.C., and Galloway, J.P. (2012) Podiform chromite deposits—database and grade and tonnage models. U.S. Geological Survey Scientific Investigations Report 2012–5157, 45 p. and database.",{"id":475,"year":476,"html":477,"doi":478},14229779,2014,"Ma, J.; Garlea, V. O.; Rondinone, A.; Aczel, A. A.; Calder, S.; dela Cruz, C.; Sinclair, R.; Tian, W.; Chi, Songxue; Kiswandhi, A.; et al. (2014) Magnetic and structural phase transitions in the spinel compound Fe1+xCr2−xO4. \u003Ci>Physical Review B\u003C\u002Fi>,  89 (13). 134106 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1103\u002Fphysrevb.89.134106'>doi:10.1103\u002Fphysrevb.89.134106\u003C\u002Fa>","10.1103\u002Fphysrevb.89.134106",{"id":480,"year":481,"html":482,"doi":483},17517,2018,"Kharbish, Sherif (2018) Raman spectroscopic features of Al- Fe3+- poor magnesiochromite and Fe2+- Fe3+- rich ferrian chromite solid solutions. \u003Ci>Mineralogy and Petrology\u003C\u002Fi>,  112 (2) 245-256 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1007\u002Fs00710-017-0531-1'>doi:10.1007\u002Fs00710-017-0531-1\u003C\u002Fa>","10.1007\u002Fs00710-017-0531-1",{"id":485,"year":486,"html":487,"doi":488},17310584,2023,"Votyakov, S. L.; Zamyatin, D. A.; Danilenko, I. A; Chashchukhin, I. S. (2023) Determination of the Iron Oxidation State in Cr-Spinels by Electron Microprobe X-ray Emission Spectroscopy of Lα,β Lines. \u003Ci>Zapiski RMO (Proceedings of the Russian Mineralogical Society)\u003C\u002Fi>,  CLII (3). 98-112 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.31857\u002Fs0869605523030085'>doi:10.31857\u002Fs0869605523030085\u003C\u002Fa>","10.31857\u002Fs0869605523030085",{"id":490,"year":486,"html":491,"doi":492},17310562,"Okrugin, A. V. (2023) Сhromite-Ulvöshpinel Series of Minerals from Alkaline Picrite-Basic Rocks of the North Siberian Platform and Their Oxythermobarometry. \u003Ci>Zapiski RMO (Proceedings of the Russian Mineralogical Society) 6\u003C\u002Fi>, 80-94 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.31857\u002Fs0869605523060035'>doi:10.31857\u002Fs0869605523060035\u003C\u002Fa>","10.31857\u002Fs0869605523060035",{"id":494,"year":495,"html":496,"doi":497},18949298,2025,"Bellesi, Manlio; Pratesi, Giovanni; Di Michele, Alessandro; Nazzareni, Sabrina; Pittarello, Lidia; Goderis, Steven; Santini, Carlo; Giuli, Gabriele (2025) Chromites in ordinary-chondrite fusion crusts. \u003Ci>European Journal of Mineralogy\u003C\u002Fi>,  37 (5). 617-626 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.5194\u002Fejm-37-617-2025'>doi:10.5194\u002Fejm-37-617-2025\u003C\u002Fa>","10.5194\u002Fejm-37-617-2025",[499,506,516,522,532,541,549,557,565,573,580,587,592,598,606,613,622,632,641,647,655,665,673,681,689,696,704,714,722,730,739,746,753,761,770,777,786,795,804,812],{"id":500,"source_url":501,"license_code":502,"credit_html":503,"title":7,"description":11,"author":11,"original_width":504,"original_height":505},29461,"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F106990","CC BY 4.0","Photo: Unknown author — http:\u002F\u002Fcreativecommons.org\u002Flicenses\u002Fby\u002F4.0\u002F, courtesy of \u003Ca href=\"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F106990\" rel=\"noopener\">Department of Geology, TalTech\u003C\u002Fa> via Europeana",1000,666,{"id":507,"source_url":508,"license_code":509,"credit_html":510,"title":511,"description":512,"author":513,"original_width":514,"original_height":515},5625,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10153741","CC BY-SA 3.0","Robert M. Lavinsky, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10153741\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite-182955.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FChromite\" class=\"extiw\" title=\"en:Chromite\">Chromite\u003C\u002Fa>\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: Freetown layered complex, Guma Water, Sierra Leone (\u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fwww.mindat.org\u002Floc-18857.html\">Locality at mindat.org\u003C\u002Fa>)\u003C\u002Fdd>\n\u003Cdd>Size: 1.3 x 1.2 x 1.2 cm.\u003C\u002Fdd>\n\u003Cdd>A huge, very sharp, complete all-around, octahedral chromite crystal from a very uncommon locality - the Freetown Layered Complex in Sierra Leone, Africa.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>","Robert M. Lavinsky",334,350,{"id":517,"source_url":518,"license_code":509,"credit_html":519,"title":520,"description":512,"author":513,"original_width":521,"original_height":515},5626,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10159217","Robert M. Lavinsky, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=10159217\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite-201529.jpg",366,{"id":523,"source_url":524,"license_code":525,"credit_html":526,"title":527,"description":528,"author":529,"original_width":530,"original_height":531},5627,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=23412401","CC BY 2.0","Mike Beauregard, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=23412401\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Yukon chromite prospect.jpg","Ultramafic rocks will bleach when weathered but are dark-coloured inside. Otherwise the black bands of chromite would not be visible. This chromite appears to be injected along stepped fractures as opposed to cumulate layering. The chromite also carries anomalous PGE (Platinum Group Element) values.\n\u003Cp>Distant view of prospect area:\nAtop 'that' mountain, near Jakes Corner, southern Yukon, Canada. \n\u003C\u002Fp>\n\u003Ca rel=\"nofollow\" class=\"external free\" href=\"https:\u002F\u002Fwww.flickr.com\u002Fphotos\u002F31856336@N03\u002F3006397421\u002F\">https:\u002F\u002Fwww.flickr.com\u002Fphotos\u002F31856336@N03\u002F3006397421\u002F\u003C\u002Fa>","Mike Beauregard",1122,912,{"id":533,"source_url":534,"license_code":525,"credit_html":535,"title":536,"description":537,"author":538,"original_width":539,"original_height":540},5582,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816688","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816688\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromitite in serpentinite (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 6.jpg","Chromitite in serpentinite in the Precambrian of Montana, USA.\n\u003Cp>This rock is at an old chromite mine in southern Montana's Red Lodge Mining District, in the Beartooth Mountains.  Active mining took place during the 1940s.  Most of the old, small mines occur on the high plateaus or just below the eroded plateau edges.\n\u003C\u002Fp>\u003Cp>Mines in the Red Lodge District targeted chromium ores in the form of black-colored chromitite rocks hosted in serpentinite and bastite (= serpentinized pyroxene).  In this area, lenses, or pods, or fault-chopped stratiform bodies of serpentinite occur among high-grade metamorphic rocks such as quartzites, gneisses, migmatites, amphibolites, etc.\n\u003C\u002Fp>\u003Cp>The rocks in the Beartooth Mountains are very old.  They are principally Archean in age (2.5+ billion years old).  The chromite-bearing serpentinite bodies of the Red Lodge District were originally chromite-bearing peridotites (dunites) of early Neoarchean age, or older.  Granulite-grade to upper amphibolite-grade regional metamorphism at about 2.75 Ga altered the original dunites to serpentinites.  The rocks of the area were also altered by greenschist-grade metamorphism between 1.6 to 1.8 billion years ago, during the late Paleoproterozoic.\n\u003C\u002Fp>\u003Cp>The dark-colored areas of this sample are chromitite, a granular-textured rock rich in the mineral chromite (FeCr2O4 - iron chromium oxide).  The greenish areas along the bottom margin are serpentinite, a low- to high-grade metamorphic rock dominated by one or more serpentine-group minerals (Mg3Si2O5(OH)4 - magnesium hydroxy-silicate).  Serpentinites range in color from light to dark green to black (sometimes whitish or bluish).  They usually have a waxy feel and luster.  Serpentinite forms by metamorphism of peridotite in the presence of water.  Peridotite is an intrusive igneous rock rich in olivine ((Mg,Fe)2SiO4 - magnesium iron silicate).\n\u003C\u002Fp>\nLocality: old chromite mine, near the eroded edge of the Beartooth Plateau, southeastern side of Rock Creek Canyon, southwest of the town of Red Lodge, Red Lodge Chromite District (Red Lodge Mining District), Beartooth Mountains, southern Montana, USA (45° 02' 04.36\" North latitude, 109° 24' 35.11\" West longitude)","James St. John",3997,2240,{"id":542,"source_url":543,"license_code":525,"credit_html":544,"title":545,"description":546,"author":538,"original_width":547,"original_height":548},5583,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816700","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816700\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromitite in serpentinite (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 3.jpg","Chromitite in serpentinite in the Precambrian of Montana, USA.\n\u003Cp>This rock is at an old chromite mine in southern Montana's Red Lodge Mining District, in the Beartooth Mountains.  Active mining took place during the 1940s.  Most of the old, small mines occur on the high plateaus or just below the eroded plateau edges.\n\u003C\u002Fp>\u003Cp>Mines in the Red Lodge District targeted chromium ores in the form of black-colored chromitite rocks hosted in serpentinite and bastite (= serpentinized pyroxene).  In this area, lenses, or pods, or fault-chopped stratiform bodies of serpentinite occur among high-grade metamorphic rocks such as quartzites, gneisses, migmatites, amphibolites, etc.\n\u003C\u002Fp>\u003Cp>The rocks in the Beartooth Mountains are very old.  They are principally Archean in age (2.5+ billion years old).  The chromite-bearing serpentinite bodies of the Red Lodge District were originally chromite-bearing peridotites (dunites) of early Neoarchean age, or older.  Granulite-grade to upper amphibolite-grade regional metamorphism at about 2.75 Ga altered the original dunites to serpentinites.  The rocks of the area were also altered by greenschist-grade metamorphism between 1.6 to 1.8 billion years ago, during the late Paleoproterozoic.\n\u003C\u002Fp>\u003Cp>The dark-colored areas of this sample are chromitite, a coarsely-crystalline textured rock rich in the mineral chromite (FeCr2O4 - iron chromium oxide).  The greenish areas along the bottom margin are serpentinite, a low- to high-grade metamorphic rock dominated by one or more serpentine-group minerals (Mg3Si2O5(OH)4 - magnesium hydroxy-silicate).  Serpentinites range in color from light to dark green to black (sometimes whitish or bluish).  They usually have a waxy feel and luster.  Serpentinite forms by metamorphism of peridotite in the presence of water.  Peridotite is an intrusive igneous rock rich in olivine ((Mg,Fe)2SiO4 - magnesium iron silicate).\n\u003C\u002Fp>\nLocality: old chromite mine, near the eroded edge of the Beartooth Plateau, southeastern side of Rock Creek Canyon, southwest of the town of Red Lodge, Red Lodge Chromite District (Red Lodge Mining District), Beartooth Mountains, southern Montana, USA (45° 02' 04.36\" North latitude, 109° 24' 35.11\" West longitude)",3391,2301,{"id":550,"source_url":551,"license_code":525,"credit_html":552,"title":553,"description":554,"author":538,"original_width":555,"original_height":556},35089,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816710","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816710\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Serpentinite (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 13.jpg","Serpentinite in the Precambrian of Montana, USA.\n\u003Cp>This rock is at an old chromite mine in southern Montana's Red Lodge Mining District, in the Beartooth Mountains.  Active mining took place during the 1940s.  Most of the old, small mines occur on the high plateaus or just below the eroded plateau edges.\n\u003C\u002Fp>\u003Cp>Mines in the Red Lodge District targeted chromium ores in the form of black-colored chromitite rocks hosted in serpentinite and bastite (= serpentinized pyroxene).  In this area, lenses, or pods, or fault-chopped stratiform bodies of serpentinite occur among high-grade metamorphic rocks such as quartzites, gneisses, migmatites, amphibolites, etc.  Chromitite is a coarsely-crystalline textured rock rich in the mineral chromite (FeCr2O4 - iron chromium oxide).\n\u003C\u002Fp>\u003Cp>The rocks in the Beartooth Mountains are very old.  They are principally Archean in age (2.5+ billion years old).  The chromite-bearing serpentinite bodies of the Red Lodge District were originally chromite-bearing peridotites (dunites) of early Neoarchean age, or older.  Granulite-grade to upper amphibolite-grade regional metamorphism at about 2.75 Ga altered the original dunites to serpentinites.  The rocks of the area were also altered by greenschist-grade metamorphism between 1.6 to 1.8 billion years ago, during the late Paleoproterozoic.\n\u003C\u002Fp>\u003Cp>This sample is serpentinite, a low- to high-grade metamorphic rock dominated by one or more serpentine-group minerals (Mg3Si2O5(OH)4 - magnesium hydroxy-silicate).  Serpentinites range in color from light to dark green to black (sometimes whitish or bluish).  They usually have a waxy feel and luster.  Serpentinite forms by metamorphism of peridotite in the presence of water.  Peridotite is an intrusive igneous rock rich in olivine ((Mg,Fe)2SiO4 - magnesium iron silicate).\n\u003C\u002Fp>\nLocality: old chromite mine, near the eroded edge of the Beartooth Plateau, southeastern side of Rock Creek Canyon, southwest of the town of Red Lodge, Red Lodge Chromite District (Red Lodge Mining District), Beartooth Mountains, southern Montana, USA (45° 02' 04.36\" North latitude, 109° 24' 35.11\" West longitude)",2751,2506,{"id":558,"source_url":559,"license_code":525,"credit_html":560,"title":561,"description":562,"author":538,"original_width":563,"original_height":564},35090,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816757","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816757\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Serpentinite (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 2.jpg","Serpentinite in the Precambrian of Montana, USA.\n\u003Cp>This rock is at an old chromite mine in southern Montana's Red Lodge Mining District, in the Beartooth Mountains.  Active mining took place during the 1940s.  Most of the old, small mines occur on the high plateaus or just below the eroded plateau edges.\n\u003C\u002Fp>\u003Cp>Mines in the Red Lodge District targeted chromium ores in the form of black-colored chromitite rocks hosted in serpentinite and bastite (= serpentinized pyroxene).  In this area, lenses, or pods, or fault-chopped stratiform bodies of serpentinite occur among high-grade metamorphic rocks such as quartzites, gneisses, migmatites, amphibolites, etc.  Chromitite is a coarsely-crystalline textured, intrusive igneous rock that is rich in the mineral chromite (FeCr2O4 - iron chromium oxide).\n\u003C\u002Fp>\u003Cp>The rocks in the Beartooth Mountains are very old.  They are principally Archean in age (2.5+ billion years old).  The chromite-bearing serpentinite bodies of the Red Lodge District were originally chromite-bearing peridotites (dunites) of early Neoarchean age, or older.  Granulite-grade to upper amphibolite-grade regional metamorphism at about 2.75 Ga altered the original dunites to serpentinites.  The rocks of the area were also altered by greenschist-grade metamorphism between 1.6 to 1.8 billion years ago, during the late Paleoproterozoic.\n\u003C\u002Fp>\u003Cp>This rock is serpentinite, a low- to high-grade metamorphic rock dominated by one or more serpentine-group minerals (Mg3Si2O5(OH)4 - magnesium hydroxy-silicate).  Serpentinites range in color from light to dark green to black.  They usually have a waxy feel and luster.  Serpentinite forms by metamorphism of peridotite in the presence of water.  Peridotite is an intrusive igneous rock rich in olivine ((Mg,Fe)2SiO4 - magnesium iron silicate).\n\u003C\u002Fp>\nLocality: old chromite mine, near the eroded edge of the Beartooth Plateau, southeastern side of Rock Creek Canyon, southwest of the town of Red Lodge, Red Lodge Chromite District (Red Lodge Mining District), Beartooth Mountains, southern Montana, USA (45° 02' 04.36\" North latitude, 109° 24' 35.11\" West longitude)",4000,3000,{"id":566,"source_url":567,"license_code":525,"credit_html":568,"title":569,"description":570,"author":538,"original_width":571,"original_height":572},39904,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=84625723","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=84625723\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromitite band in chromitic serpentinite (early Neoarchean; North Star Mine, near eroded edge of Hellroaring Plateau, Red Lodge Chromite District, Beartooth Mountains, southern Montana, USA) (15188887016).jpg","\u003Cp>Chromitite band in chromitic serpentinite from the Precambrian of Montana's Beartooth Mountains, USA. (6.5 cm across along the base)\n\u003C\u002Fp>\u003Cp>The Red Lodge Mining District is located near the southeastern termination of the Beartooth Mountains, southwest of the town of Red Lodge in southern Montana, USA.  Active mining took place during the 1940s.  Most of the old, small mines occur on the high plateaus or just below the eroded plateau edges (for example, along the northwestern margin of Rock Creek Canyon).\n\u003C\u002Fp>\u003Cp>Mines in the Red Lodge District targeted chromium ores in the form of chromitite rocks hosted in serpentinite.  Lenses, or pods, or fault-chopped stratiform bodies of serpentinite occur among high-grade metamorphic rocks (quartzites, gneisses, migmatites, amphibolites, etc.).\n\u003C\u002Fp>\u003Cp>The rocks in the Beartooth Mountains are very old.  They are principally Archean in age (>2.5 billion years old).  The chromite-bearing serpentinite bodies of the Red Lodge Mining District were originally chromite-bearing peridotites (dunites) of early Neoarchean age, or older.  Granulite-grade to upper amphibolite-grade regional metamorphism at about 2.75 Ga altered the original chromitic dunites to serpentinites.  The rocks of the area were also altered by greenschist-grade metamorphism between 1.6 to 1.8 billion years ago, during the late Paleoproterozoic.\n\u003C\u002Fp>\u003Cp>Chromitite is a crystalline-textured, intrusive igneous rock exclusively or near exclusively composed of the mineral chromite (FeCr2O4 - iron chromium oxide).  The black, granular part of the rock shown above is chromitite, which forms a band running through greenish-colored serpentinite.  Serpentinite is a metamorphic rock, the result of alteration of olivine-rich peridotites (dunites) in the presence of water.  The serpentinite itself contains scattered black chromite crystals.\n\u003C\u002Fp>\u003Cp>Age: Archean (early Neoarchean metamorphism at 2.75 Ga, plus late Paleoproterozoic metamorphism at 1.6 to 1.8 Ga).\n\u003C\u002Fp>\nLocality: North Star Mine (North Star Claim), old chromite mine rock pile along Hellroaring Road (Forest Service Road 2004), near eroded edge of Hellroaring Plateau, northwestern side of Rock Creek Canyon, southeast of Hellroaring Lakes & southwest of the town of Red Lodge, Red Lodge Chromite District (Red Lodge Mining District; Hellroaring Mining District), Beartooth Mountains, southern Montana, USA (45° 02' 09.94\" North latitude, 109° 26' 48.49\" West longitude)",3260,2692,{"id":574,"source_url":575,"license_code":525,"credit_html":576,"title":577,"description":537,"author":538,"original_width":578,"original_height":579},39911,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816672","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816672\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromitite in serpentinite (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 7.jpg",3485,2361,{"id":581,"source_url":582,"license_code":525,"credit_html":583,"title":584,"description":585,"author":538,"original_width":563,"original_height":586},39913,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816679","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816679\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromitite with serpentinite (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 3.jpg","Chromitite with serpentinite in the Precambrian of Montana, USA.\n\u003Cp>This rock is at an old chromite mine in southern Montana's Red Lodge Mining District, in the Beartooth Mountains.  Active mining took place during the 1940s.  Most of the old, small mines occur on the high plateaus or just below the eroded plateau edges.\n\u003C\u002Fp>\u003Cp>Mines in the Red Lodge District targeted chromium ores in the form of black-colored chromitite rocks hosted in serpentinite and bastite (= serpentinized pyroxene).  In this area, lenses, or pods, or fault-chopped stratiform bodies of serpentinite occur among high-grade metamorphic rocks such as quartzites, gneisses, migmatites, amphibolites, etc.\n\u003C\u002Fp>\u003Cp>The rocks in the Beartooth Mountains are very old.  They are principally Archean in age (2.5+ billion years old).  The chromite-bearing serpentinite bodies of the Red Lodge District were originally chromite-bearing peridotites (dunites) of early Neoarchean age, or older.  Granulite-grade to upper amphibolite-grade regional metamorphism at about 2.75 Ga altered the original dunites to serpentinites.  The rocks of the area were also altered by greenschist-grade metamorphism between 1.6 to 1.8 billion years ago, during the late Paleoproterozoic.\n\u003C\u002Fp>\u003Cp>The dark-colored areas of this sample are chromitite, a granular-textured rock rich in the mineral chromite (FeCr2O4 - iron chromium oxide).  The greenish areas are serpentinite, a low- to high-grade metamorphic rock dominated by one or more serpentine-group minerals (Mg3Si2O5(OH)4 - magnesium hydroxy-silicate).  Serpentinites range in color from light to dark green to black (sometimes whitish or bluish).  They usually have a waxy feel and luster.  Serpentinite forms by metamorphism of peridotite in the presence of water.  Peridotite is an intrusive igneous rock rich in olivine ((Mg,Fe)2SiO4 - magnesium iron silicate).\n\u003C\u002Fp>\nLocality: old chromite mine, near the eroded edge of the Beartooth Plateau, southeastern side of Rock Creek Canyon, southwest of the town of Red Lodge, Red Lodge Chromite District (Red Lodge Mining District), Beartooth Mountains, southern Montana, USA (45° 02' 04.36\" North latitude, 109° 24' 35.11\" West longitude)",2797,{"id":588,"source_url":589,"license_code":525,"credit_html":590,"title":591,"description":585,"author":538,"original_width":563,"original_height":220},39914,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816682","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816682\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromitite with serpentinite (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 1.jpg",{"id":593,"source_url":594,"license_code":525,"credit_html":595,"title":596,"description":537,"author":538,"original_width":563,"original_height":597},39915,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816690","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816690\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromitite in serpentinite (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 5.jpg",2127,{"id":599,"source_url":600,"license_code":525,"credit_html":601,"title":602,"description":603,"author":538,"original_width":604,"original_height":605},39916,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816691","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816691\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromitite (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 1.jpg","Chromitite in the Precambrian of Montana, USA.\n\u003Cp>This rock is at an old chromite mine in southern Montana's Red Lodge Mining District, in the Beartooth Mountains.  Active mining took place during the 1940s.  Most of the old, small mines occur on the high plateaus or just below the eroded plateau edges.\n\u003C\u002Fp>\u003Cp>Mines in the Red Lodge District targeted chromium ores in the form of black-colored chromitite rocks hosted in serpentinite and bastite (= serpentinized pyroxene).  In this area, lenses, or pods, or fault-chopped stratiform bodies of serpentinite occur among high-grade metamorphic rocks such as quartzites, gneisses, migmatites, amphibolites, etc.\n\u003C\u002Fp>\u003Cp>The rocks in the Beartooth Mountains are very old.  They are principally Archean in age (2.5+ billion years old).  The chromite-bearing serpentinite bodies of the Red Lodge District were originally chromite-bearing peridotites (dunites) of early Neoarchean age, or older.  Granulite-grade to upper amphibolite-grade regional metamorphism at about 2.75 Ga altered the original dunites to serpentinites.  The rocks of the area were also altered by greenschist-grade metamorphism between 1.6 to 1.8 billion years ago, during the late Paleoproterozoic.\n\u003C\u002Fp>\u003Cp>Chromitite is a granular-textured rock rich in the mineral chromite (FeCr2O4 - iron chromium oxide).\n\u003C\u002Fp>\nLocality: old chromite mine, near the eroded edge of the Beartooth Plateau, southeastern side of Rock Creek Canyon, southwest of the town of Red Lodge, Red Lodge Chromite District (Red Lodge Mining District), Beartooth Mountains, southern Montana, USA (45° 02' 04.36\" North latitude, 109° 24' 35.11\" West longitude)",3988,2345,{"id":607,"source_url":608,"license_code":525,"credit_html":609,"title":610,"description":546,"author":538,"original_width":611,"original_height":612},39917,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816696","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816696\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromitite in serpentinite (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 4.jpg",3816,2545,{"id":614,"source_url":615,"license_code":509,"credit_html":616,"title":617,"description":618,"author":619,"original_width":620,"original_height":621},5629,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=40424267","Leon Hupperichs, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=40424267\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite-478691.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FChromite\" class=\"extiw\" title=\"en:Chromite\">Chromite\u003C\u002Fa>\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: Mtoroshanga (Mutorashanga), Makonde District (Lomagundi District), Mashonaland West, Zimbabwe\u003C\u002Fdd>\n\u003Cdd>Field of view 2.5 cm. Specimen and photo Leon Hupperichs.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>","Leon Hupperichs",968,794,{"id":623,"source_url":624,"license_code":625,"credit_html":626,"title":627,"description":628,"author":629,"original_width":630,"original_height":631},5628,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=34983383","Public domain","Weinrich Minerals, Inc., via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=34983383\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite.jpg","Chromite - Mtoroshanga, Makonde District, Mashonaland West, Zimbabwe\n\u003Cp>Size: 7.0 x 4.5 x 3.0 cm\n\u003C\u002Fp>\nMostly covered by crude crystals and crystallized chromite.","Weinrich Minerals, Inc.",1004,724,{"id":633,"source_url":634,"license_code":509,"credit_html":635,"title":636,"description":637,"author":638,"original_width":639,"original_height":640},8809,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=65958199","Łukasz Kruszewski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=65958199\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Ferronickelplatinum, Chromite-68411.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FFerronickelplatinum\" class=\"extiw\" title=\"en:Ferronickelplatinum\">Ferronickelplatinum\u003C\u002Fa>, \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FChromite\" class=\"extiw\" title=\"en:Chromite\">Chromite\u003C\u002Fa>\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: Urals Region, Russia\u003C\u002Fdd>\n\u003Cdd>\u003Ci>Original description:\u003C\u002Fi> Small (4 mm in diameter) nugget of the sample obtained as native platinum, but showed to contain essential Pt, Fe and Ni - thus revalidated to ferronickelplatinum. Specimen comes from a placer probably from nearby Nizhne Tagilsk, contains small chromite grains and awaits future microprobe analysis.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>","Łukasz Kruszewski",1232,964,{"id":642,"source_url":643,"license_code":509,"credit_html":644,"title":645,"description":646,"author":638,"original_width":639,"original_height":640},8810,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=65958203","Łukasz Kruszewski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=65958203\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Ferronickelplatinum, Chromite-68413.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FFerronickelplatinum\" class=\"extiw\" title=\"en:Ferronickelplatinum\">Ferronickelplatinum\u003C\u002Fa>\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: Urals Region, Russia\u003C\u002Fdd>\n\u003Cdd>\u003Ci>Original description:\u003C\u002Fi> Small (4 mm in diameter) nugget of the sample obtained as native platinum, but showed to contain essential Pt, Fe and Ni - thus revalidated to ferronickelplatinum. Specimen comes from a placer probably from nearby Nizhne Tagilsk, contains small chromite grains and awaits future microprobe analysis.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>",{"id":648,"source_url":649,"license_code":525,"credit_html":650,"title":651,"description":652,"author":538,"original_width":653,"original_height":654},35088,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816651","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816651\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite & serpentine (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 1.jpg","Chromite-serpentine rock in the Precambrian of Montana, USA.\n\u003Cp>This rock is at an old chromite mine in southern Montana's Red Lodge Mining District, in the Beartooth Mountains.  Active mining took place during the 1940s.  Most of the old, small mines occur on the high plateaus or just below the eroded plateau edges.\n\u003C\u002Fp>\u003Cp>Mines in the Red Lodge District targeted chromium ores in the form of black-colored chromitite rocks hosted in serpentinite and bastite (= serpentinized pyroxene).  In this area, lenses, or pods, or fault-chopped stratiform bodies of serpentinite occur among high-grade metamorphic rocks such as quartzites, gneisses, migmatites, amphibolites, etc.\n\u003C\u002Fp>\u003Cp>The rocks in the Beartooth Mountains are very old.  They are principally Archean in age (2.5+ billion years old).  The chromite-bearing serpentinite bodies of the Red Lodge District were originally chromite-bearing peridotites (dunites) of early Neoarchean age, or older.  Granulite-grade to upper amphibolite-grade regional metamorphism at about 2.75 Ga altered the original dunites to serpentinites.  The rocks of the area were also altered by greenschist-grade metamorphism between 1.6 to 1.8 billion years ago, during the late Paleoproterozoic.\n\u003C\u002Fp>\u003Cp>The greenish specks in the rock are serpentinite, a low- to high-grade metamorphic rock dominated by one or more serpentine-group minerals (Mg3Si2O5(OH)4 - magnesium hydroxy-silicate).  Serpentinites range in color from light to dark green to black (sometimes whitish or bluish).  They usually have a waxy feel and luster.  Serpentinite forms by metamorphism of peridotite in the presence of water.  Peridotite is an intrusive igneous rock rich in olivine ((Mg,Fe)2SiO4 - magnesium iron silicate).  The dark specks iare chromitite, a granular-textured rock rich in the mineral chromite (FeCr2O4 - iron chromium oxide).\n\u003C\u002Fp>\nLocality: old chromite mine, near the eroded edge of the Beartooth Plateau, southeastern side of Rock Creek Canyon, southwest of the town of Red Lodge, Red Lodge Chromite District (Red Lodge Mining District), Beartooth Mountains, southern Montana, USA (45° 02' 04.36\" North latitude, 109° 24' 35.11\" West longitude)",3039,2039,{"id":656,"source_url":657,"license_code":658,"credit_html":659,"title":660,"description":661,"author":662,"original_width":663,"original_height":664},37846,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=163475748","CC0 1.0","Darla Sondrol, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=163475748\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Pyroxenite (harzburgite) (GeoDIL number - 235).jpg","This harzburgite from the Stillwater Complex, Near Nye, Montana, is mostly composed of orthopyroxene (bronzite), with subordinate amounts of olivine and calcic plagioclase, and very minor clinopyroxene and chromite. The specimen is 9 cm across.","Darla Sondrol",2662,1860,{"id":666,"source_url":667,"license_code":525,"credit_html":668,"title":669,"description":670,"author":538,"original_width":671,"original_height":672},39906,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358250","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358250\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Uvarovite garnets on chromitite (Saranovskiy Massif; Sarany Chromite Mine, Ural Mountains, Russia) 1.jpg","Uvarovite garnets on chromitite from Russia. (~2.6 cm across at its widest)\n\u003Cp>A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties.  At its simplest, a mineral is a naturally-occurring solid chemical.  Currently, there are about 5400 named and described minerals - about 200 of them are common and about 20 of them are very common.  Mineral classification is based on anion chemistry.  Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.\n\u003C\u002Fp>\u003Cp>The silicates are the most abundant and chemically complex group of minerals.  All silicates have silica as the basis for their chemistry.  \"Silica\" refers to SiO2 chemistry.  The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4.  Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens \"belong\" to each silicon.  The resulting formula for silica is thus SiO2, not SiO4.\n\u003C\u002Fp>\u003Cp>Garnet is a group of silicate minerals.  Garnets are expected to be red to dark red in color - many of them are, but several garnet varieties can be other colors, including purple, orange, olive green, deep green, and black.  Garnets form 12-sided crystals (dodecahedrons) or crystals with even more faces on them.  The crystals become more and more rounded as the crystal face number increases.  Garnet has a nonmetallic, glassy luster, whitish streak, is quite hard (H = 7), has no cleavage, and has conchoidal fracture.\n\u003C\u002Fp>\u003Cp>Common examples of garnet include almandine, grossular, spessartine, and andradite.\n\u003C\u002Fp>\u003Cp>Almandine is an iron-aluminum garnet (ideally Fe3Al2Si3O12 - iron aluminum silicate).  Almandine is the most common type of garnet - it is commonly encountered as well formed crystals in schists.  It is also found in some igneous rocks.  Almandine is classically used as a mineral indicator of regional metamorphism.  Initially, the development of large, undeformed garnets in metamorphic rocks may seem odd.  However, some metamorphic minerals ignore external pressures as they grow.  Staurolite and pyrite, both common metamorphic minerals, do the same thing.\n\u003C\u002Fp>\u003Cp>Grossular is a calcium-aluminum garnet (ideally Ca3Al2Si3O12 - calcium aluminum silicate).  It typically forms after argillaceous limestones have been contact metamorphosed or regionally metamorphosed.\n\u003C\u002Fp>\u003Cp>Spessartine is a manganese-aluminum garnet (ideally Mn3Al2Si3O12 - manganese aluminum silicate).  It is typically reddish to brownish in color.  It is often reported in skarns (contact metamorphosed rocks) and rocks enriched in manganese.\n\u003C\u002Fp>\u003Cp>Andradite is the most common variety of calcium garnet.  Andradite is a calcium-iron garnet (Ca3Fe2Si3O12 - calcium iron silicate).  It varies in color from yellowish to greenish to brownish to blackish.  Green, chromium-bearing andradite is called demantoid.  Black, titanium-bearing andradite is called melanite.\n\u003C\u002Fp>\u003Cp>The deep green-colored crystals shown above are a scarce type of chromium garnet called uvarovite (Ca3Cr2(SiO4)3 - calcium chromium silicate).  The black-colored host rock is chromitite, a crystalline-textured intrusive igneous rock almost exclusively composed of chromite (FeCr2O4 - iron chromium oxide).  The uvarovite garnets are fracture-filling and hydrothermal in origin.\n\u003C\u002Fp>\u003Cp>The chromitite host rock is from an ultramafic igneous intrusion called the Saranovskiy Massif, which contains gabbro, gabbronorite, and serpentinitzed chromititic peridotite.  The intrusion is hosted in Precambrian-aged metamorphic rocks (schists and quartzites).  I have not seen published isotopic ages for the Saranovskiy Massif.  The only hint of a geologic age that I have encountered is the non-informative term \"Caledonian\", which may refer to the Silurian and Devonian.\n\u003C\u002Fp>\u003Cp>Locality: Sarany Chromite Mine (Saranovskiy Mine), near the village of Sarany (Saranovskaya), ~12 kilometers north of the Biserskoye Chromite Deposit, Permaskaya District (Perm District), Middle Ural Mountains, western Russia\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of almandine:\nwww.mindat.org\u002Fgallery.php?min=452\n\u003C\u002Fp>\u003Cp>Photo gallery of grossular:\nwww.mindat.org\u002Fgallery.php?min=1755\n\u003C\u002Fp>\u003Cp>Photo gallery of spessartine:\nwww.mindat.org\u002Fgallery.php?min=3725\n\u003C\u002Fp>\u003Cp>Photo gallery of andradite:\nwww.mindat.org\u002Fgallery.php?min=223\n\u003C\u002Fp>\u003Cp>Photo gallery of melanite:\nwww.mindat.org\u002Fgallery.php?min=7443\n\u003C\u002Fp>\u003Cp>Photo gallery of uvarovite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=4125",1745,1129,{"id":674,"source_url":675,"license_code":525,"credit_html":676,"title":677,"description":678,"author":538,"original_width":679,"original_height":680},39907,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358254","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358254\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Uvarovite garnets on chromitite (Saranovskiy Massif; Sarany Chromite Mine, Ural Mountains, Russia) 3.jpg","Uvarovite garnets on chromitite from Russia.\n\u003Cp>A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties.  At its simplest, a mineral is a naturally-occurring solid chemical.  Currently, there are about 5400 named and described minerals - about 200 of them are common and about 20 of them are very common.  Mineral classification is based on anion chemistry.  Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.\n\u003C\u002Fp>\u003Cp>The silicates are the most abundant and chemically complex group of minerals.  All silicates have silica as the basis for their chemistry.  \"Silica\" refers to SiO2 chemistry.  The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4.  Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens \"belong\" to each silicon.  The resulting formula for silica is thus SiO2, not SiO4.\n\u003C\u002Fp>\u003Cp>Garnet is a group of silicate minerals.  Garnets are expected to be red to dark red in color - many of them are, but several garnet varieties can be other colors, including purple, orange, olive green, deep green, and black.  Garnets form 12-sided crystals (dodecahedrons) or crystals with even more faces on them.  The crystals become more and more rounded as the crystal face number increases.  Garnet has a nonmetallic, glassy luster, whitish streak, is quite hard (H = 7), has no cleavage, and has conchoidal fracture.\n\u003C\u002Fp>\u003Cp>Common examples of garnet include almandine, grossular, spessartine, and andradite.\n\u003C\u002Fp>\u003Cp>Almandine is an iron-aluminum garnet (ideally Fe3Al2Si3O12 - iron aluminum silicate).  Almandine is the most common type of garnet - it is commonly encountered as well formed crystals in schists.  It is also found in some igneous rocks.  Almandine is classically used as a mineral indicator of regional metamorphism.  Initially, the development of large, undeformed garnets in metamorphic rocks may seem odd.  However, some metamorphic minerals ignore external pressures as they grow.  Staurolite and pyrite, both common metamorphic minerals, do the same thing.\n\u003C\u002Fp>\u003Cp>Grossular is a calcium-aluminum garnet (ideally Ca3Al2Si3O12 - calcium aluminum silicate).  It typically forms after argillaceous limestones have been contact metamorphosed or regionally metamorphosed.\n\u003C\u002Fp>\u003Cp>Spessartine is a manganese-aluminum garnet (ideally Mn3Al2Si3O12 - manganese aluminum silicate).  It is typically reddish to brownish in color.  It is often reported in skarns (contact metamorphosed rocks) and rocks enriched in manganese.\n\u003C\u002Fp>\u003Cp>Andradite is the most common variety of calcium garnet.  Andradite is a calcium-iron garnet (Ca3Fe2Si3O12 - calcium iron silicate).  It varies in color from yellowish to greenish to brownish to blackish.  Green, chromium-bearing andradite is called demantoid.  Black, titanium-bearing andradite is called melanite.\n\u003C\u002Fp>\u003Cp>The deep green-colored crystals shown above are a scarce type of chromium garnet called uvarovite (Ca3Cr2(SiO4)3 - calcium chromium silicate).  The black-colored host rock is chromitite, a crystalline-textured intrusive igneous rock almost exclusively composed of chromite (FeCr2O4 - iron chromium oxide).  The uvarovite garnets are fracture-filling and hydrothermal in origin.\n\u003C\u002Fp>\u003Cp>The chromitite host rock is from an ultramafic igneous intrusion called the Saranovskiy Massif, which contains gabbro, gabbronorite, and serpentinitzed chromititic peridotite.  The intrusion is hosted in Precambrian-aged metamorphic rocks (schists and quartzites).  I have not seen published isotopic ages for the Saranovskiy Massif.  The only hint of a geologic age that I have encountered is the non-informative term \"Caledonian\", which may refer to the Silurian and Devonian.\n\u003C\u002Fp>\u003Cp>Locality: Sarany Chromite Mine (Saranovskiy Mine), near the village of Sarany (Saranovskaya), ~12 kilometers north of the Biserskoye Chromite Deposit, Permaskaya District (Perm District), Middle Ural Mountains, western Russia\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of almandine:\nwww.mindat.org\u002Fgallery.php?min=452\n\u003C\u002Fp>\u003Cp>Photo gallery of grossular:\nwww.mindat.org\u002Fgallery.php?min=1755\n\u003C\u002Fp>\u003Cp>Photo gallery of spessartine:\nwww.mindat.org\u002Fgallery.php?min=3725\n\u003C\u002Fp>\u003Cp>Photo gallery of andradite:\nwww.mindat.org\u002Fgallery.php?min=223\n\u003C\u002Fp>\u003Cp>Photo gallery of melanite:\nwww.mindat.org\u002Fgallery.php?min=7443\n\u003C\u002Fp>\u003Cp>Photo gallery of uvarovite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=4125",2372,1569,{"id":682,"source_url":683,"license_code":525,"credit_html":684,"title":685,"description":686,"author":538,"original_width":687,"original_height":688},39908,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358255","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358255\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Uvarovite garnets on chromitite (Saranovskiy Massif; Sarany Chromite Mine, Ural Mountains, Russia) 4.jpg","Uvarovite garnets on chromitite from Russia. (~3.9 cm across at its widest)\n\u003Cp>A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties.  At its simplest, a mineral is a naturally-occurring solid chemical.  Currently, there are about 5400 named and described minerals - about 200 of them are common and about 20 of them are very common.  Mineral classification is based on anion chemistry.  Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.\n\u003C\u002Fp>\u003Cp>The silicates are the most abundant and chemically complex group of minerals.  All silicates have silica as the basis for their chemistry.  \"Silica\" refers to SiO2 chemistry.  The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4.  Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens \"belong\" to each silicon.  The resulting formula for silica is thus SiO2, not SiO4.\n\u003C\u002Fp>\u003Cp>Garnet is a group of silicate minerals.  Garnets are expected to be red to dark red in color - many of them are, but several garnet varieties can be other colors, including purple, orange, olive green, deep green, and black.  Garnets form 12-sided crystals (dodecahedrons) or crystals with even more faces on them.  The crystals become more and more rounded as the crystal face number increases.  Garnet has a nonmetallic, glassy luster, whitish streak, is quite hard (H = 7), has no cleavage, and has conchoidal fracture.\n\u003C\u002Fp>\u003Cp>Common examples of garnet include almandine, grossular, spessartine, and andradite.\n\u003C\u002Fp>\u003Cp>Almandine is an iron-aluminum garnet (ideally Fe3Al2Si3O12 - iron aluminum silicate).  Almandine is the most common type of garnet - it is commonly encountered as well formed crystals in schists.  It is also found in some igneous rocks.  Almandine is classically used as a mineral indicator of regional metamorphism.  Initially, the development of large, undeformed garnets in metamorphic rocks may seem odd.  However, some metamorphic minerals ignore external pressures as they grow.  Staurolite and pyrite, both common metamorphic minerals, do the same thing.\n\u003C\u002Fp>\u003Cp>Grossular is a calcium-aluminum garnet (ideally Ca3Al2Si3O12 - calcium aluminum silicate).  It typically forms after argillaceous limestones have been contact metamorphosed or regionally metamorphosed.\n\u003C\u002Fp>\u003Cp>Spessartine is a manganese-aluminum garnet (ideally Mn3Al2Si3O12 - manganese aluminum silicate).  It is typically reddish to brownish in color.  It is often reported in skarns (contact metamorphosed rocks) and rocks enriched in manganese.\n\u003C\u002Fp>\u003Cp>Andradite is the most common variety of calcium garnet.  Andradite is a calcium-iron garnet (Ca3Fe2Si3O12 - calcium iron silicate).  It varies in color from yellowish to greenish to brownish to blackish.  Green, chromium-bearing andradite is called demantoid.  Black, titanium-bearing andradite is called melanite.\n\u003C\u002Fp>\u003Cp>The deep green-colored crystals shown above are a scarce type of chromium garnet called uvarovite (Ca3Cr2(SiO4)3 - calcium chromium silicate).  The black-colored host rock is chromitite, a crystalline-textured intrusive igneous rock almost exclusively composed of chromite (FeCr2O4 - iron chromium oxide).  The uvarovite garnets are fracture-filling and hydrothermal in origin.\n\u003C\u002Fp>\u003Cp>The chromitite host rock is from an ultramafic igneous intrusion called the Saranovskiy Massif, which contains gabbro, gabbronorite, and serpentinitzed chromititic peridotite.  The intrusion is hosted in Precambrian-aged metamorphic rocks (schists and quartzites).  I have not seen published isotopic ages for the Saranovskiy Massif.  The only hint of a geologic age that I have encountered is the non-informative term \"Caledonian\", which may refer to the Silurian and Devonian.\n\u003C\u002Fp>\u003Cp>Locality: Sarany Chromite Mine (Saranovskiy Mine), near the village of Sarany (Saranovskaya), ~12 kilometers north of the Biserskoye Chromite Deposit, Permaskaya District (Perm District), Middle Ural Mountains, western Russia\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of almandine:\nwww.mindat.org\u002Fgallery.php?min=452\n\u003C\u002Fp>\u003Cp>Photo gallery of grossular:\nwww.mindat.org\u002Fgallery.php?min=1755\n\u003C\u002Fp>\u003Cp>Photo gallery of spessartine:\nwww.mindat.org\u002Fgallery.php?min=3725\n\u003C\u002Fp>\u003Cp>Photo gallery of andradite:\nwww.mindat.org\u002Fgallery.php?min=223\n\u003C\u002Fp>\u003Cp>Photo gallery of melanite:\nwww.mindat.org\u002Fgallery.php?min=7443\n\u003C\u002Fp>\u003Cp>Photo gallery of uvarovite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=4125",3037,1797,{"id":690,"source_url":691,"license_code":525,"credit_html":692,"title":693,"description":686,"author":538,"original_width":694,"original_height":695},39909,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358256","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358256\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Uvarovite garnets on chromitite (Saranovskiy Massif; Sarany Chromite Mine, Ural Mountains, Russia) 2.jpg",2497,1408,{"id":697,"source_url":698,"license_code":525,"credit_html":699,"title":700,"description":701,"author":538,"original_width":702,"original_height":703},39910,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358266","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358266\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Uvarovite garnets on chromitite (Saranovskiy Massif; Sarany Chromite Mine, Ural Mountains, Russia) 6.jpg","Uvarovite garnets on chromitite from Russia. (~8.4 centimeters across at its widest)\n\u003Cp>A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties.  At its simplest, a mineral is a naturally-occurring solid chemical.  Currently, there are about 5400 named and described minerals - about 200 of them are common and about 20 of them are very common.  Mineral classification is based on anion chemistry.  Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.\n\u003C\u002Fp>\u003Cp>The silicates are the most abundant and chemically complex group of minerals.  All silicates have silica as the basis for their chemistry.  \"Silica\" refers to SiO2 chemistry.  The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4.  Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens \"belong\" to each silicon.  The resulting formula for silica is thus SiO2, not SiO4.\n\u003C\u002Fp>\u003Cp>Garnet is a group of silicate minerals.  Garnets are expected to be red to dark red in color - many of them are, but several garnet varieties can be other colors, including purple, orange, olive green, deep green, and black.  Garnets form 12-sided crystals (dodecahedrons) or crystals with even more faces on them.  The crystals become more and more rounded as the crystal face number increases.  Garnet has a nonmetallic, glassy luster, whitish streak, is quite hard (H = 7), has no cleavage, and has conchoidal fracture.\n\u003C\u002Fp>\u003Cp>Common examples of garnet include almandine, grossular, spessartine, and andradite.\n\u003C\u002Fp>\u003Cp>Almandine is an iron-aluminum garnet (ideally Fe3Al2Si3O12 - iron aluminum silicate).  Almandine is the most common type of garnet - it is commonly encountered as well formed crystals in schists.  It is also found in some igneous rocks.  Almandine is classically used as a mineral indicator of regional metamorphism.  Initially, the development of large, undeformed garnets in metamorphic rocks may seem odd.  However, some metamorphic minerals ignore external pressures as they grow.  Staurolite and pyrite, both common metamorphic minerals, do the same thing.\n\u003C\u002Fp>\u003Cp>Grossular is a calcium-aluminum garnet (ideally Ca3Al2Si3O12 - calcium aluminum silicate).  It typically forms after argillaceous limestones have been contact metamorphosed or regionally metamorphosed.\n\u003C\u002Fp>\u003Cp>Spessartine is a manganese-aluminum garnet (ideally Mn3Al2Si3O12 - manganese aluminum silicate).  It is typically reddish to brownish in color.  It is often reported in skarns (contact metamorphosed rocks) and rocks enriched in manganese.\n\u003C\u002Fp>\u003Cp>Andradite is the most common variety of calcium garnet.  Andradite is a calcium-iron garnet (Ca3Fe2Si3O12 - calcium iron silicate).  It varies in color from yellowish to greenish to brownish to blackish.  Green, chromium-bearing andradite is called demantoid.  Black, titanium-bearing andradite is called melanite.\n\u003C\u002Fp>\u003Cp>The deep green-colored crystals shown above are a scarce type of chromium garnet called uvarovite (Ca3Cr2(SiO4)3 - calcium chromium silicate).  The black-colored host rock is chromitite, a crystalline-textured intrusive igneous rock almost exclusively composed of chromite (FeCr2O4 - iron chromium oxide).  The uvarovite garnets are fracture-filling and hydrothermal in origin.\n\u003C\u002Fp>\u003Cp>The chromitite host rock is from an ultramafic igneous intrusion called the Saranovskiy Massif, which contains gabbro, gabbronorite, and serpentinitzed chromititic peridotite.  The intrusion is hosted in Precambrian-aged metamorphic rocks (schists and quartzites).  I have not seen published isotopic ages for the Saranovskiy Massif.  The only hint of a geologic age that I have encountered is the non-informative term \"Caledonian\", which may refer to the Silurian and Devonian.\n\u003C\u002Fp>\u003Cp>Locality: Sarany Chromite Mine (Saranovskiy Mine), near the village of Sarany (Saranovskaya), ~12 kilometers north of the Biserskoye Chromite Deposit, Permaskaya District (Perm District), Middle Ural Mountains, western Russia\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of almandine:\nwww.mindat.org\u002Fgallery.php?min=452\n\u003C\u002Fp>\u003Cp>Photo gallery of grossular:\nwww.mindat.org\u002Fgallery.php?min=1755\n\u003C\u002Fp>\u003Cp>Photo gallery of spessartine:\nwww.mindat.org\u002Fgallery.php?min=3725\n\u003C\u002Fp>\u003Cp>Photo gallery of andradite:\nwww.mindat.org\u002Fgallery.php?min=223\n\u003C\u002Fp>\u003Cp>Photo gallery of melanite:\nwww.mindat.org\u002Fgallery.php?min=7443\n\u003C\u002Fp>\u003Cp>Photo gallery of uvarovite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=4125",2425,2547,{"id":705,"source_url":706,"license_code":707,"credit_html":708,"title":709,"description":710,"author":711,"original_width":712,"original_height":713},39997,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=5302763","CC BY-SA 4.0","Piotr Sosnowski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=5302763\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromit 1.jpg","Chromite, localization unknown","Piotr Sosnowski",1837,1469,{"id":715,"source_url":716,"license_code":707,"credit_html":717,"title":718,"description":719,"author":711,"original_width":720,"original_height":721},39998,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=9412311","Piotr Sosnowski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=9412311\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite poland.jpg","\u003Ca href=\"\u002F\u002Fcommons.wikimedia.org\u002Fwiki\u002FChromite\" class=\"mw-redirect\" title=\"Chromite\">Chromite\u003C\u002Fa>",800,640,{"id":723,"source_url":724,"license_code":509,"credit_html":725,"title":726,"description":727,"author":619,"original_width":728,"original_height":729},39999,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=14866511","Leon Hupperichs, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=14866511\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite-108705.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FChromite\" class=\"extiw\" title=\"en:Chromite\">Chromite\u003C\u002Fa>\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: Mtoroshanga (Mutorashanga), Mashonaland West, Zimbabwe\u003C\u002Fdd>\n\u003Cdd>Field of view 8 mm. Specimen and photo Leon Hupperichs.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>",776,564,{"id":731,"source_url":732,"license_code":625,"credit_html":733,"title":734,"description":735,"author":736,"original_width":737,"original_height":738},40000,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=15092646","Andrew Silver, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=15092646\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite - USGS Mineral Specimens 290.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FChromite\" class=\"extiw\" title=\"en:Chromite\">Chromite\u003C\u002Fa> (Pen for scale)\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: unknown\u003C\u002Fdd>\n\u003Cdd>\u003Ci>Original description:\u003C\u002Fi> Chromite (Spinel). Pen for scale. Mineral collection of Brigham Young University Department of Geology, Provo, Utah. Photograph by Andrew Silver. BYU index 4-6017, FeCr\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>","Andrew Silver",1400,1094,{"id":740,"source_url":741,"license_code":625,"credit_html":742,"title":743,"description":744,"author":736,"original_width":737,"original_height":745},40001,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=15092819","Andrew Silver, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=15092819\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite - USGS Mineral Specimens 292.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FChromite\" class=\"extiw\" title=\"en:Chromite\">Chromite\u003C\u002Fa> (Pen for scale)\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: unknown\u003C\u002Fdd>\n\u003Cdd>\u003Ci>Original description:\u003C\u002Fi> Chromite (Spinel). Pen for scale. Mineral collection of Brigham Young University Department of Geology, Provo, Utah. Photograph by Andrew Silver. BYU index 4-6021a, FeCr\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>",1090,{"id":747,"source_url":748,"license_code":625,"credit_html":749,"title":750,"description":751,"author":736,"original_width":737,"original_height":752},40002,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=15092830","Andrew Silver, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=15092830\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite - USGS Mineral Specimens 293.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FChromite\" class=\"extiw\" title=\"en:Chromite\">Chromite\u003C\u002Fa> (Pen for scale)\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: unknown\u003C\u002Fdd>\n\u003Cdd>\u003Ci>Original description:\u003C\u002Fi> Chromite (Spinel). Pen for scale. Mineral collection of Brigham Young University Department of Geology, Provo, Utah. Photograph by Andrew Silver. BYU index 4-6021b, FeCr\u003Csub>2\u003C\u002Fsub>O\u003Csub>4\u003C\u002Fsub>.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>",1113,{"id":754,"source_url":755,"license_code":509,"credit_html":756,"title":757,"description":758,"author":513,"original_width":759,"original_height":760},40004,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=40424608","Robert M. Lavinsky, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=40424608\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite-641038.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FChromite\" class=\"extiw\" title=\"en:Chromite\">Chromite\u003C\u002Fa>\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>Locality: Hangha, Kenema District, Eastern Province, Sierra Leone\u003C\u002Fdd>\n\u003Cdd>Size: 1.4 cm x 1.2 cm x 1.1 cm\u003C\u002Fdd>\n\u003Cdd>Chromite is a multiple oxide with Cr and is a member of the Spinel Group. It is found as a cumulate mineral layer in ultramafic igneous rocks, in peridotites or with associated placer deposits. It is also common in meteorites except carbonaceous chondrites (MINDAT). The sharp black metallic octahedron has a resinous lustre. Pristine. A contact on one corner has no damage, per se. That's brown wax on one face. Probably older material from this obscure locale, but no proof. Ex. Carl Davis Collection. Rarely available.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>",465,531,{"id":762,"source_url":763,"license_code":707,"credit_html":764,"title":765,"description":766,"author":767,"original_width":768,"original_height":769},40006,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=83015917","Tõnis Saadre, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=83015917\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Estonian Museum of Natural History Specimen No 195197 photo (g122 g122-10 jpg).jpg","\"kromiit\", \"kromiit\". More info \u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fgeocollections.info\u002Ffile\u002F90692\">about this file\u003C\u002Fa> and \u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fgeocollections.info\u002Fspecimen\u002F195197\">about this specimen\u003C\u002Fa> at \u003Ca rel=\"nofollow\" class=\"external text\" href=\"http:\u002F\u002Fgeocollections.info\u002F\">geocollections.info\u003C\u002Fa>","Tõnis Saadre",3352,2920,{"id":771,"source_url":772,"license_code":525,"credit_html":773,"title":774,"description":775,"author":538,"original_width":563,"original_height":776},40007,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816712","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=126816712\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite band in serpentinite (Neoarchean; Red Lodge Chromite District, Beartooth Mountains, Montana, USA) 7.jpg","Chromite band in serpentinite in the Precambrian of Montana, USA.\n\u003Cp>This rock is at an old chromite mine in southern Montana's Red Lodge Mining District, in the Beartooth Mountains.  Active mining took place during the 1940s.  Most of the old, small mines occur on the high plateaus or just below the eroded plateau edges.\n\u003C\u002Fp>\u003Cp>Mines in the Red Lodge District targeted chromium ores in the form of black-colored chromitite rocks hosted in serpentinite and bastite (= serpentinized pyroxene).  In this area, lenses, or pods, or fault-chopped stratiform bodies of serpentinite occur among high-grade metamorphic rocks such as quartzites, gneisses, migmatites, amphibolites, etc.\n\u003C\u002Fp>\u003Cp>The rocks in the Beartooth Mountains are very old.  They are principally Archean in age (2.5+ billion years old).  The chromite-bearing serpentinite bodies of the Red Lodge District were originally chromite-bearing peridotites (dunites) of early Neoarchean age, or older.  Granulite-grade to upper amphibolite-grade regional metamorphism at about 2.75 Ga altered the original dunites to serpentinites.  The rocks of the area were also altered by greenschist-grade metamorphism between 1.6 to 1.8 billion years ago, during the late Paleoproterozoic.\n\u003C\u002Fp>\u003Cp>The greenish portions of the rock are serpentinite, a low- to high-grade metamorphic rock dominated by one or more serpentine-group minerals (Mg3Si2O5(OH)4 - magnesium hydroxy-silicate).  Serpentinites range in color from light to dark green to black (sometimes whitish or bluish).  They usually have a waxy feel and luster.  Serpentinite forms by metamorphism of peridotite in the presence of water.  Peridotite is an intrusive igneous rock rich in olivine ((Mg,Fe)2SiO4 - magnesium iron silicate).  The dark band is chromitite, a coarsely-crystalline textured rock rich in the mineral chromite (FeCr2O4 - iron chromium oxide).\n\u003C\u002Fp>\nLocality: old chromite mine, near the eroded edge of the Beartooth Plateau, southeastern side of Rock Creek Canyon, southwest of the town of Red Lodge, Red Lodge Chromite District (Red Lodge Mining District), Beartooth Mountains, southern Montana, USA (45° 02' 04.36\" North latitude, 109° 24' 35.11\" West longitude)",2807,{"id":778,"source_url":779,"license_code":707,"credit_html":780,"title":781,"description":782,"author":783,"original_width":784,"original_height":785},40009,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=156295900","Любмир, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=156295900\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Хромі́т, хромистий залізняк — мінерал.png","Chromite ironstone — mineral","Любмир",542,677,{"id":787,"source_url":788,"license_code":707,"credit_html":789,"title":790,"description":791,"author":792,"original_width":793,"original_height":794},40010,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=191743951","Fernando Losada Rodríguez, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=191743951\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Cromita (IES Terra de Xallas).001 - Geolodía Santa Comba 2026.jpg","Roca con cristales de cromita, expuesta en el patio del IES Terra de Xallas, en Santa Comba (A Coruña, Galicia, España).","Fernando Losada Rodríguez",1771,2959,{"id":796,"source_url":797,"license_code":798,"credit_html":799,"title":800,"description":801,"author":802,"original_width":563,"original_height":803},73061,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=118185823","CC BY-SA 2.0","Pacific Museum of Earth from Canada, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=118185823\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Chromite with Penninite (47975535448).jpg","\u003Cp>Gross Valley\n\u003C\u002Fp>\nCalifornia, USA","Pacific Museum of Earth from Canada",6000,{"id":805,"source_url":806,"license_code":525,"credit_html":807,"title":808,"description":809,"author":538,"original_width":810,"original_height":811},83157,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358265","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358265\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Uvarovite garnets on chromitite (Saranovskiy Massif; Sarany Chromite Mine, Ural Mountains, Russia) 7.jpg","Uvarovite garnets on chromitite from Russia. (~8.8 centimeters across at its widest)\n\u003Cp>A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties.  At its simplest, a mineral is a naturally-occurring solid chemical.  Currently, there are about 5400 named and described minerals - about 200 of them are common and about 20 of them are very common.  Mineral classification is based on anion chemistry.  Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.\n\u003C\u002Fp>\u003Cp>The silicates are the most abundant and chemically complex group of minerals.  All silicates have silica as the basis for their chemistry.  \"Silica\" refers to SiO2 chemistry.  The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4.  Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens \"belong\" to each silicon.  The resulting formula for silica is thus SiO2, not SiO4.\n\u003C\u002Fp>\u003Cp>Garnet is a group of silicate minerals.  Garnets are expected to be red to dark red in color - many of them are, but several garnet varieties can be other colors, including purple, orange, olive green, deep green, and black.  Garnets form 12-sided crystals (dodecahedrons) or crystals with even more faces on them.  The crystals become more and more rounded as the crystal face number increases.  Garnet has a nonmetallic, glassy luster, whitish streak, is quite hard (H = 7), has no cleavage, and has conchoidal fracture.\n\u003C\u002Fp>\u003Cp>Common examples of garnet include almandine, grossular, spessartine, and andradite.\n\u003C\u002Fp>\u003Cp>Almandine is an iron-aluminum garnet (ideally Fe3Al2Si3O12 - iron aluminum silicate).  Almandine is the most common type of garnet - it is commonly encountered as well formed crystals in schists.  It is also found in some igneous rocks.  Almandine is classically used as a mineral indicator of regional metamorphism.  Initially, the development of large, undeformed garnets in metamorphic rocks may seem odd.  However, some metamorphic minerals ignore external pressures as they grow.  Staurolite and pyrite, both common metamorphic minerals, do the same thing.\n\u003C\u002Fp>\u003Cp>Grossular is a calcium-aluminum garnet (ideally Ca3Al2Si3O12 - calcium aluminum silicate).  It typically forms after argillaceous limestones have been contact metamorphosed or regionally metamorphosed.\n\u003C\u002Fp>\u003Cp>Spessartine is a manganese-aluminum garnet (ideally Mn3Al2Si3O12 - manganese aluminum silicate).  It is typically reddish to brownish in color.  It is often reported in skarns (contact metamorphosed rocks) and rocks enriched in manganese.\n\u003C\u002Fp>\u003Cp>Andradite is the most common variety of calcium garnet.  Andradite is a calcium-iron garnet (Ca3Fe2Si3O12 - calcium iron silicate).  It varies in color from yellowish to greenish to brownish to blackish.  Green, chromium-bearing andradite is called demantoid.  Black, titanium-bearing andradite is called melanite.\n\u003C\u002Fp>\u003Cp>The deep green-colored crystals shown above are a scarce type of chromium garnet called uvarovite (Ca3Cr2(SiO4)3 - calcium chromium silicate).  The black-colored host rock is chromitite, a crystalline-textured intrusive igneous rock almost exclusively composed of chromite (FeCr2O4 - iron chromium oxide).  The uvarovite garnets are fracture-filling and hydrothermal in origin.\n\u003C\u002Fp>\u003Cp>The chromitite host rock is from an ultramafic igneous intrusion called the Saranovskiy Massif, which contains gabbro, gabbronorite, and serpentinitzed chromititic peridotite.  The intrusion is hosted in Precambrian-aged metamorphic rocks (schists and quartzites).  I have not seen published isotopic ages for the Saranovskiy Massif.  The only hint of a geologic age that I have encountered is the non-informative term \"Caledonian\", which may refer to the Silurian and Devonian.\n\u003C\u002Fp>\u003Cp>Locality: Sarany Chromite Mine (Saranovskiy Mine), near the village of Sarany (Saranovskaya), ~12 kilometers north of the Biserskoye Chromite Deposit, Permaskaya District (Perm District), Middle Ural Mountains, western Russia\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of almandine:\nwww.mindat.org\u002Fgallery.php?min=452\n\u003C\u002Fp>\u003Cp>Photo gallery of grossular:\nwww.mindat.org\u002Fgallery.php?min=1755\n\u003C\u002Fp>\u003Cp>Photo gallery of spessartine:\nwww.mindat.org\u002Fgallery.php?min=3725\n\u003C\u002Fp>\u003Cp>Photo gallery of andradite:\nwww.mindat.org\u002Fgallery.php?min=223\n\u003C\u002Fp>\u003Cp>Photo gallery of melanite:\nwww.mindat.org\u002Fgallery.php?min=7443\n\u003C\u002Fp>\u003Cp>Photo gallery of uvarovite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=4125",2681,2529,{"id":813,"source_url":814,"license_code":525,"credit_html":815,"title":816,"description":817,"author":538,"original_width":818,"original_height":819},83158,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358267","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=96358267\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Uvarovite garnets on chromitite (Saranovskiy Massif; Sarany Chromite Mine, Ural Mountains, Russia) 5.jpg","Uvarovite garnets on chromitite from Russia. (~3.9 centimeters across at its widest)\n\u003Cp>A mineral is a naturally-occurring, solid, inorganic, crystalline substance having a fairly definite chemical composition and having fairly definite physical properties.  At its simplest, a mineral is a naturally-occurring solid chemical.  Currently, there are over 5600 named and described minerals - about 200 of them are common and about 20 of them are very common.  Mineral classification is based on anion chemistry.  Major categories of minerals are: elements, sulfides, oxides, halides, carbonates, sulfates, phosphates, and silicates.\n\u003C\u002Fp>\u003Cp>The silicates are the most abundant and chemically complex group of minerals.  All silicates have silica as the basis for their chemistry.  \"Silica\" refers to SiO2 chemistry.  The fundamental molecular unit of silica is one small silicon atom surrounded by four large oxygen atoms in the shape of a triangular pyramid - this is the silica tetrahedron - SiO4.  Each oxygen atom is shared by two silicon atoms, so only half of the four oxygens \"belong\" to each silicon.  The resulting formula for silica is thus SiO2, not SiO4.\n\u003C\u002Fp>\u003Cp>Garnet is a group of silicate minerals.  Garnets are expected to be red to dark red in color - many of them are, but several garnet varieties can be other colors, including purple, orange, olive green, deep green, and black.  Garnets form 12-sided crystals (dodecahedrons) or crystals with even more faces on them.  The crystals become more and more rounded as the crystal face number increases.  Garnet has a nonmetallic, glassy luster, whitish streak, is quite hard (H = 7), has no cleavage, and has conchoidal fracture.\n\u003C\u002Fp>\u003Cp>Common examples of garnet include almandine, grossular, spessartine, and andradite.\n\u003C\u002Fp>\u003Cp>Almandine is an iron-aluminum garnet (ideally Fe3Al2Si3O12 - iron aluminum silicate).  Almandine is the most common type of garnet - it is commonly encountered as well formed crystals in schists.  It is also found in some igneous rocks.  Almandine is classically used as a mineral indicator of regional metamorphism.  Initially, the development of large, undeformed garnets in metamorphic rocks may seem odd.  However, some metamorphic minerals ignore external pressures as they grow.  Staurolite and pyrite, both common metamorphic minerals, do the same thing.\n\u003C\u002Fp>\u003Cp>Grossular is a calcium-aluminum garnet (ideally Ca3Al2Si3O12 - calcium aluminum silicate).  It typically forms after argillaceous limestones have been contact metamorphosed or regionally metamorphosed.\n\u003C\u002Fp>\u003Cp>Spessartine is a manganese-aluminum garnet (ideally Mn3Al2Si3O12 - manganese aluminum silicate).  It is typically reddish to brownish in color.  It is often reported in skarns (contact metamorphosed rocks) and rocks enriched in manganese.\n\u003C\u002Fp>\u003Cp>Andradite is the most common variety of calcium garnet.  Andradite is a calcium-iron garnet (Ca3Fe2Si3O12 - calcium iron silicate).  It varies in color from yellowish to greenish to brownish to blackish.  Green, chromium-bearing andradite is called demantoid.  Black, titanium-bearing andradite is called melanite.\n\u003C\u002Fp>\u003Cp>The deep green-colored crystals shown above are a scarce type of chromium garnet called uvarovite (Ca3Cr2(SiO4)3 - calcium chromium silicate).  The black-colored host rock is chromitite, a crystalline-textured intrusive igneous rock almost exclusively composed of chromite (FeCr2O4 - iron chromium oxide).  The uvarovite garnets are fracture-filling and hydrothermal in origin.\n\u003C\u002Fp>\u003Cp>The chromitite host rock is from an ultramafic igneous intrusion called the Saranovskiy Massif, which contains gabbro, gabbronorite, and serpentinitzed chromitic peridotite.  The intrusion is hosted in Precambrian-aged metamorphic rocks (schists and quartzites).  I have not seen published isotopic ages for the Saranovskiy Massif.  The only hint of a geologic age that I have encountered is the non-informative term \"Caledonian\", which may refer to the Silurian and Devonian.\n\u003C\u002Fp>\u003Cp>Locality: Sarany Chromite Mine (Saranovskiy Mine), near the village of Sarany (Saranovskaya), ~12 kilometers north of the Biserskoye Chromite Deposit, Permaskaya District (Perm District), Middle Ural Mountains, western Russia\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of almandine:\nwww.mindat.org\u002Fgallery.php?min=452\n\u003C\u002Fp>\u003Cp>Photo gallery of grossular:\nwww.mindat.org\u002Fgallery.php?min=1755\n\u003C\u002Fp>\u003Cp>Photo gallery of spessartine:\nwww.mindat.org\u002Fgallery.php?min=3725\n\u003C\u002Fp>\u003Cp>Photo gallery of andradite:\nwww.mindat.org\u002Fgallery.php?min=223\n\u003C\u002Fp>\u003Cp>Photo gallery of melanite:\nwww.mindat.org\u002Fgallery.php?min=7443\n\u003C\u002Fp>\u003Cp>Photo gallery of uvarovite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=4125",2507,1486,[821,827,834,839,844],{"id":822,"url":823,"label":824,"formula":825,"spacegroup":826,"year":476},2711,"\u002Fcif\u002F2711.cif","Ishii 2014","Fe Cr2 O4","P n m a",{"id":828,"url":829,"label":830,"formula":831,"spacegroup":832,"year":833},2712,"\u002Fcif\u002F2712.cif","Lenaz 2009 · Mg.567 Mn.009 Fe.479 Al.19 Ti.004 Cr1.75 O4","Mg.567 Mn.009 Fe.479 Al.19 Ti.004 Cr1.75 O4","F d 3 m",2009,{"id":835,"url":836,"label":837,"formula":838,"spacegroup":832,"year":833},2713,"\u002Fcif\u002F2713.cif","Lenaz 2009 · Mg.601 Al.223 Mn.007 Fe.444 Ti.002 Cr1.722 O4","Mg.601 Al.223 Mn.007 Fe.444 Ti.002 Cr1.722 O4",{"id":840,"url":841,"label":842,"formula":843,"spacegroup":832,"year":833},2714,"\u002Fcif\u002F2714.cif","Lenaz 2009 · Mg.589 Al.218 Mn.008 Fe.452 Ti.012 Cr1.72 O4","Mg.589 Al.218 Mn.008 Fe.452 Ti.012 Cr1.72 O4",{"id":845,"url":846,"label":847,"formula":848,"spacegroup":832,"year":833},2715,"\u002Fcif\u002F2715.cif","Lenaz 2009 · Mg.609 Al.246 Mn.008 Fe.431 Cr1.702 Ni.004 O4","Mg.609 Al.246 Mn.008 Fe.431 Cr1.702 Ni.004 O4",[850,851,852,853,854,855,856,857,858,859,860,861,862,863,864,865,866,867,868,869,870,871,872,873,874,875,876],"Autunite (of Leymerie)","Beresofite (of Simpson)","Chromate of Iron","Chromeisenerz","Chromeisenspinell","Chromeisenstein","Chromic Iron","Chromjernmalm","Chromoferrit","Chromoferrite","Chrompicotite (of Lacroix)","Chromsaures Eisen","Cromoferrita","Cromoferrite","Eisenchrom","Eisenchrome","Fer chromaté","Fer chromaté aluminé","Fer chromé","Ferro cromato","Ferrochromate","Ferrochromit","Ferrochromita","Ferrochromite","Hierro cromado","Siderochrome","Siderocromo",[878,882,886,891,895,899,906,910,914,917,921,925,929,933,940,944,948,952,956,960,964,968,974,978,982,985,989,993,996,1000,1004,1009,1014,1017,1020,1023,1027,1031,1034,1037,1040,1043,1046,1049,1052,1056,1059,1063,1066,1069,1073,1076,1079],{"lang":879,"names":880},"af",[881],"Chromiet",{"lang":883,"names":884},"ar",[885],"كروميت",{"lang":887,"names":888},"az",[889,890],"Xromit","Xromşpinelidlər",{"lang":892,"names":893},"ca",[894],"cromita",{"lang":896,"names":897},"cs",[898],"Chromit",{"lang":900,"names":901},"de",[902,853,854,855,903,898,858,861,904,905,864,871],"Chromeisen","Chromerz","Chromspinell","Cr2FeO4",{"lang":907,"names":908},"el",[909],"Χρωμίτης",{"lang":911,"names":912},"eo",[913],"Kromito",{"lang":915,"names":916},"es",[894],{"lang":918,"names":919},"et",[920],"kromiit",{"lang":922,"names":923},"eu",[924],"Kromita",{"lang":926,"names":927},"fa",[928],"کرومیت",{"lang":930,"names":931},"fi",[932],"Kromiitti",{"lang":934,"names":935},"fr",[936,937,938,939],"1308-31-2","chromite","FeCr2O4","FeO·Cr2O3",{"lang":941,"names":942},"gl",[943],"Cromita",{"lang":945,"names":946},"he",[947],"כרומיט",{"lang":949,"names":950},"hi",[951],"क्रोमाइट",{"lang":953,"names":954},"hu",[955],"kromit",{"lang":957,"names":958},"hy",[959],"Քրոմիտ",{"lang":961,"names":962},"id",[963],"Kromit",{"lang":965,"names":966},"it",[7,967],"cromite",{"lang":969,"names":970},"ja",[971,972,973],"クローム鉄鉱","クロマイト","クロム鉄鉱",{"lang":975,"names":976},"kk",[977],"Хромит",{"lang":979,"names":980},"ko",[981],"크로마이트",{"lang":983,"names":984},"ky",[977],{"lang":986,"names":987},"lt",[988],"Chromitas",{"lang":990,"names":991},"mg",[992],"Krômita",{"lang":994,"names":995},"mk",[977],{"lang":997,"names":998},"mn",[999],"Кромит",{"lang":1001,"names":1002},"nb",[1003],"kromitt",{"lang":1005,"names":1006},"nds",[1007,1008,898],"Chromiesenierz","Chromiesensteen",{"lang":1010,"names":1011},"nl",[1012,1013],"chromiet","chromietzand",{"lang":1015,"names":1016},"nn",[1003],{"lang":1018,"names":1019},"oc",[937,943],{"lang":1021,"names":1022},"pl",[898],{"lang":1024,"names":1025},"pt",[894,1026],"Cromite",{"lang":1028,"names":1029},"ro",[1030],"Cromit",{"lang":1032,"names":1033},"ru",[977],{"lang":1035,"names":1036},"sh",[963],{"lang":1038,"names":1039},"sk",[898],{"lang":1041,"names":1042},"sl",[963],{"lang":1044,"names":1045},"sr",[977],{"lang":1047,"names":1048},"sv",[963],{"lang":1050,"names":1051},"tr",[955],{"lang":1053,"names":1054},"uk",[1055],"Хроміт",{"lang":1057,"names":1058},"vi",[898,1030],{"lang":1060,"names":1061},"zh",[1062],"铬铁矿",{"lang":1064,"names":1065},"zh-cn",[1062],{"lang":1067,"names":1068},"zh-hans",[1062],{"lang":1070,"names":1071},"zh-hant",[1072],"鉻鐵礦",{"lang":1074,"names":1075},"zh-hk",[1072],{"lang":1077,"names":1078},"zh-sg",[1062],{"lang":1080,"names":1081},"zh-tw",[1072],"Q107172",{"history":11,"applications":11}]