[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"minerals:one:2308":3},{"id":4,"longid":5,"guid":6,"name":7,"shortcode_ima":8,"entrytype":9,"entrytype_text":10,"varietyof":11,"synid":8,"polytypeof":8,"groupid":8,"weighting":12,"nolocadd":13,"blacklisted":13,"mindat_formula":14,"mindat_formula_note":15,"ima_formula":8,"elements":16,"sigelements":22,"key_elements":8,"impurities":8,"cim":8,"ima_status":8,"ima_notes":8,"ima_history":8,"approval_year":8,"publication_year":8,"discovery_year":8,"strunz10ed1":23,"strunz10ed2":23,"strunz10ed3":23,"strunz10ed4":8,"dana8ed1":23,"dana8ed2":23,"dana8ed3":23,"dana8ed4":23,"csystem":8,"cclass":8,"spacegroup":8,"spacegroupset":23,"a":8,"b":8,"c":8,"alpha":8,"beta":8,"gamma":8,"aerror":8,"berror":8,"cerror":8,"alphaerror":8,"betaerror":8,"gammaerror":8,"va3":8,"z":8,"csmetamict":13,"commentcrystal":8,"twinning":8,"tranglide":8,"parting":8,"epitaxidescription":8,"morphology":8,"tlform":8,"hmin":24,"hmax":25,"hardtype":8,"vhnmin":23,"vhnmax":23,"vhnerror":8,"vhng":8,"vhns":8,"commenthard":8,"dmeas":23,"dmeas2":23,"dcalc":23,"dmeaserror":8,"dcalcerror":8,"commentdense":8,"lustre":8,"lustretype":26,"commentluster":8,"diapheny":8,"streak":27,"colour":28,"commentcolor":8,"colors":29,"streak_colors":35,"luminescence":8,"uv":8,"cleavage":8,"cleavagetype":36,"fracturetype":8,"tenacity":8,"commentbreak":8,"opticaltype":37,"opticalsign":38,"opticalalpha":39,"opticalalpha2":40,"opticalalphaerror":8,"opticalbeta":41,"opticalbeta2":42,"opticalbetaerror":8,"opticalgamma":43,"opticalgamma2":44,"opticalgammaerror":8,"opticalomega":8,"opticalomega2":23,"opticalomegaerror":8,"opticalepsilon":8,"opticalepsilon2":23,"opticalepsilonerror":8,"opticaln":8,"opticaln2":8,"opticalnerror":8,"optical2vcalc":45,"optical2vcalc2":46,"optical2vcalcerror":8,"optical2vmeasured":47,"optical2vmeasured2":23,"optical2vmeasurederror":8,"rimin":48,"rimax":49,"opticaldispersion":50,"opticalpleochroism":8,"opticalpleochorismdesc":8,"opticalbirefringence":8,"opticalcomments":8,"opticalcolour":8,"opticalinternal":8,"opticaltropic":8,"opticalanisotropism":8,"opticalbireflectance":8,"opticalextinction":8,"opticalr":8,"specdispm":8,"ir":8,"electrical":8,"magnetism":8,"thermalbehaviour":8,"other":8,"industrial":8,"occurrence":8,"otheroccurrence":8,"type_specimen_store":8,"description_short":8,"aboutname":51,"rock_parent":8,"rock_parent2":8,"rock_root":52,"rock_bgs_code":8,"meteoritical_code":8,"updttime":53,"reviewed_at":8,"variety_of":54,"varieties":62,"group_members":70,"associates":71,"confused_with":72,"type_localities":73,"occurrence_total":80,"citations":81,"images":144,"structures":451,"synonyms":479,"language_names":505,"wikidata_qid":8,"texts":506},2308,"1:1:2308:1","16bfbd97-1469-466f-98b0-b3200d787bdb","Labradorite",null,2,"variety",246,2603,false,"(Ca,Na)[Al(Al,Si)Si\u003Csub>2\u003C\u002Fsub>O\u003Csub>8\u003C\u002Fsub>]","Albite : anorthite molar ratio ranges from 30 : 70 to 50 : 50.",[17,18,19,20,21],"Al","Ca","Na","Si","O",[17,18,20,21],"0",6,6.5,"Sub-Vitreous","White","Pale green, blue, colourless, grey-white",[30,31,32,33,34],"green","blue","colorless","gray","white",[34],"Perfect","Biaxial","+","1.554","1.563","1.5588","1.5675","1.562","1.573","78","86","85",1.554,1.573,"none","From the occurrence at Ford Harbour, Paul Island, Labrador, Canada (Nain anorthosite).",0,"2026-05-14 18:34:27",{"id":11,"name":55,"entrytype":52,"csystem":56,"ima_formula":57,"mindat_formula":57,"hmin":24,"hmax":25,"dmeas":58,"dcalc":59,"strunz10ed1":60,"primary_image_id":61},"Anorthite","Triclinic","Ca(Al\u003Csub>2\u003C\u002Fsub>Si\u003Csub>2\u003C\u002Fsub>O\u003Csub>8\u003C\u002Fsub>)","2.74","2.76","9",1515,[63,66],{"id":64,"name":65,"entrytype":9,"csystem":8,"ima_formula":8,"mindat_formula":57,"hmin":8,"hmax":8,"dmeas":23,"dcalc":23,"primary_image_id":8},27155,"Oregon Sunstone",{"id":67,"name":68,"entrytype":9,"csystem":8,"ima_formula":8,"mindat_formula":57,"hmin":8,"hmax":8,"dmeas":8,"dcalc":8,"primary_image_id":69},9131,"Spectrolite",89324,[],[],[],[74],{"id":75,"txt":76,"latitude":77,"longitude":78,"country":79},256513,"Ford Harbour, Paul Island, Nain Complex, Labrador, Newfoundland and Labrador, Canada",56.4569444,-61.1941667,"Canada",490,[82,86,91,96,101,106,111,115,119,124,129,134,139],{"id":83,"year":84,"html":85,"doi":8},16099733,1823,"Rose. G. (1823) Über den Feldspat, Albit, Labradorit und Anorthit. Annalen der Physik und Chemie: 73\u002FNF-43: 175-208.",{"id":87,"year":88,"html":89,"doi":90},4494,1955,"Muir, I. D. (1955) Transitional optics of some andesines and labradorites. \u003Ci>Mineralogical Magazine and Journal of the Mineralogical Society\u003C\u002Fi>,  30 (228) 545-568 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1180\u002Fminmag.1955.030.228.01'>doi:10.1180\u002Fminmag.1955.030.228.01\u003C\u002Fa> \u003Ca target='_blank' href='https:\u002F\u002Frruff.info\u002Fdoclib\u002FMinMag\u002FVolume_30\u002F30-228-545.pdf' class='refpdflink'>\u003C\u002Fa>","10.1180\u002Fminmag.1955.030.228.01",{"id":92,"year":93,"html":94,"doi":95},4938607,1966,"Bolton, H. C., Bursill, L. A., McLaren, A. C., Turner, R. G. (1966) On the origin of the colour of labradorite. \u003Ci>physica status solidi (b)\u003C\u002Fi>, 18 (1). 221-230 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1002\u002Fpssb.19660180123'>doi:10.1002\u002Fpssb.19660180123\u003C\u002Fa>","10.1002\u002Fpssb.19660180123",{"id":97,"year":98,"html":99,"doi":100},190256,1988,"Steurer, W.; Jagodzinski, H. (1988) The incommensurately modulated structure of an andesine (An\u003Csub>38\u003C\u002Fsub>). \u003Ci>Acta Crystallographica Section B Structural Science\u003C\u002Fi>,  44 (4). p.344-351. \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1107\u002Fs0108768188001806'>doi:10.1107\u002Fs0108768188001806\u003C\u002Fa>","10.1107\u002Fs0108768188001806",{"id":102,"year":103,"html":104,"doi":105},112983,1992,"Burandt, B., Komorek, M., Schnabel, B., Press, W., Boysen, H. (1992) High resolution X-ray investigations on the supersatellite reflections of Labradorite. \u003Ci>Zeitschrift für Kristallographie - Crystalline Materials\u003C\u002Fi>,  200 (1) 141-156 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1524\u002Fzkri.1992.200.1-2.141'>doi:10.1524\u002Fzkri.1992.200.1-2.141\u003C\u002Fa>","10.1524\u002Fzkri.1992.200.1-2.141",{"id":107,"year":108,"html":109,"doi":110},8437601,1997,"Kalning, M.; Dorna, V.; Burandt, B.; Press, W.; Kek, S.; Boysen, H. (1997) High-Order Supersatellite Reflections in Labradorite. A Synchrotron X-ray Diffraction Study. \u003Ci>Acta Crystallographica Section A Foundations of Crystallography\u003C\u002Fi>,  53 (5). 632-642 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1107\u002Fs010876739700500x'>doi:10.1107\u002Fs010876739700500x\u003C\u002Fa>","10.1107\u002Fs010876739700500x",{"id":112,"year":113,"html":114,"doi":8},16965462,2001,"(2001) Labradorite. \u003Ci>Handbook of Mineralogy\u003C\u002Fi>. Mineralogical Society of America \u003Ca target='_blank' href='https:\u002F\u002Fwww.handbookofmineralogy.org\u002Fpdfs\u002Flabradorite.pdf' class='refpdflink'>\u003C\u002Fa>",{"id":116,"year":117,"html":118,"doi":8},16114482,2013,"rruff.info (n.d.) \u003Ca target='_blank' rel='nofollow' href='http:\u002F\u002Frruff.info\u002Fdoclib\u002Fhom\u002Flabradorite.pdf'>http:\u002F\u002Frruff.info\u002Fdoclib\u002Fhom\u002Flabradorite.pdf\u003C\u002Fa>",{"id":120,"year":121,"html":122,"doi":123},117718,2014,"Boysen, Hans; Kek, Stefan (2014) The modulated structure of labradorite. \u003Ci>Zeitschrift für Kristallographie - Crystalline Materials\u003C\u002Fi>,  230 (1). 23-35 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1515\u002Fzkri-2014-1749'>doi:10.1515\u002Fzkri-2014-1749\u003C\u002Fa>","10.1515\u002Fzkri-2014-1749",{"id":125,"year":126,"html":127,"doi":128},398398,2017,"Jin, Shiyun, Xu, Huifang (2017) Study on structure variations of incommensurately modulated labradorite feldspars with different cooling histories. \u003Ci>American Mineralogist\u003C\u002Fi>,  102 (6) 1328-1339 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.2138\u002Fam-2017-6003'>doi:10.2138\u002Fam-2017-6003\u003C\u002Fa>","10.2138\u002Fam-2017-6003",{"id":130,"year":131,"html":132,"doi":133},8511652,2020,"Jin, Shiyun, Xu, Huifang, Wang, Xiaoping, Jacobs, Ryan, Morgan, Dane (2020) The incommensurately modulated structures of low-temperature labradorite feldspars: a single-crystal X-ray and neutron diffraction study. \u003Ci>Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials\u003C\u002Fi>, 76 (1). 93-107 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.1107\u002Fs2052520619017128'>doi:10.1107\u002Fs2052520619017128\u003C\u002Fa>","10.1107\u002Fs2052520619017128",{"id":135,"year":136,"html":137,"doi":138},13421931,2021,"Jin, Shiyun, Xu, Huifang, Lee, Seungyeol (2021) Revisiting the Bøggild Intergrowth in Iridescent Labradorite Feldspars: Ordering, Kinetics, and Phase Equilibria. \u003Ci>Minerals\u003C\u002Fi>, 11 (7) 727 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.3390\u002Fmin11070727'>doi:10.3390\u002Fmin11070727\u003C\u002Fa> \u003Ca target='_blank' href='https:\u002F\u002Fwww.mdpi.com\u002F2075-163X\u002F11\u002F7\u002F727\u002Fpdf?version=1625552371' class='refpdflink'>\u003C\u002Fa>","10.3390\u002Fmin11070727",{"id":140,"year":141,"html":142,"doi":143},16114481,2022,"Götz, Emilia; Kleebe, Hans-Joachim; Kolb, Ute (2022) The hierarchical internal structure of labradorite. \u003Ci>European Journal of Mineralogy\u003C\u002Fi>,  34 (5). 393-410 \u003Ca target='_blank' href='https:\u002F\u002Fdoi.org\u002F10.5194\u002Fejm-34-393-2022'>doi:10.5194\u002Fejm-34-393-2022\u003C\u002Fa>","10.5194\u002Fejm-34-393-2022",[145,155,162,168,172,181,185,190,200,206,211,220,229,239,248,256,265,274,282,291,299,306,314,321,329,336,343,350,360,369,377,384,391,398,406,413,421,428,436,443],{"id":146,"source_url":147,"license_code":148,"credit_html":149,"title":150,"description":151,"author":152,"original_width":153,"original_height":154},63448,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=704828","CC BY-SA 3.0","Simon Eugster --Simon 20:25, 14 April 2006 (UTC), via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=704828\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","LabradoritD.jpg","Labradorit, labradorisierend","Simon Eugster --Simon 20:25, 14 April 2006 (UTC)",1600,1200,{"id":156,"source_url":157,"license_code":158,"credit_html":159,"title":7,"description":8,"author":8,"original_width":160,"original_height":161},88590,"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F65350","CC BY-SA 4.0","Photo: Unknown author — http:\u002F\u002Fcreativecommons.org\u002Flicenses\u002Fby-sa\u002F4.0\u002F, courtesy of \u003Ca href=\"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F65350\" rel=\"noopener\">The Estonian Museum of Natural History\u003C\u002Fa> via Europeana",1000,700,{"id":163,"source_url":164,"license_code":165,"credit_html":166,"title":7,"description":8,"author":8,"original_width":160,"original_height":167},88591,"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F108681","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\u002F108681\" rel=\"noopener\">Department of Geology, TalTech\u003C\u002Fa> via Europeana",666,{"id":169,"source_url":170,"license_code":165,"credit_html":171,"title":7,"description":8,"author":8,"original_width":160,"original_height":167},88592,"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F116480","Photo: Unknown author — http:\u002F\u002Fcreativecommons.org\u002Flicenses\u002Fby\u002F4.0\u002F, courtesy of \u003Ca href=\"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F116480\" rel=\"noopener\">Department of Geology, TalTech\u003C\u002Fa> via Europeana",{"id":173,"source_url":174,"license_code":148,"credit_html":175,"title":176,"description":177,"author":178,"original_width":179,"original_height":180},63451,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=927046","Linnell, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=927046\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite.jpg","A polished slab of a rock containing labradorite","Linnell",810,598,{"id":182,"source_url":183,"license_code":165,"credit_html":184,"title":7,"description":8,"author":8,"original_width":160,"original_height":167},88593,"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F108712","Photo: Unknown author — http:\u002F\u002Fcreativecommons.org\u002Flicenses\u002Fby\u002F4.0\u002F, courtesy of \u003Ca href=\"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F108712\" rel=\"noopener\">Department of Geology, TalTech\u003C\u002Fa> via Europeana",{"id":186,"source_url":187,"license_code":158,"credit_html":188,"title":7,"description":8,"author":8,"original_width":160,"original_height":189},88594,"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F90932","Photo: Unknown author — http:\u002F\u002Fcreativecommons.org\u002Flicenses\u002Fby-sa\u002F4.0\u002F, courtesy of \u003Ca href=\"https:\u002F\u002Fgeocollections.info\u002Ffile\u002F90932\" rel=\"noopener\">The Estonian Museum of Natural History\u003C\u002Fa> via Europeana",546,{"id":191,"source_url":192,"license_code":193,"credit_html":194,"title":195,"description":196,"author":197,"original_width":198,"original_height":199},63453,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=5462777","Public domain","Parent Géry, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=5462777\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite polie 2 (Madagascar).jpg","bloc de labradorite polie","Parent Géry",4288,2848,{"id":201,"source_url":202,"license_code":193,"credit_html":203,"title":204,"description":205,"author":197,"original_width":198,"original_height":199},63454,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=5656211","Parent Géry, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=5656211\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite polie 3(Madagascar).jpg","\u003Ca href=\"\u002F\u002Fcommons.wikimedia.org\u002Fwiki\u002FLabradorite\" class=\"mw-redirect\" title=\"Labradorite\">Labradorite\u003C\u002Fa>",{"id":207,"source_url":208,"license_code":193,"credit_html":209,"title":210,"description":205,"author":197,"original_width":198,"original_height":199},63455,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=5695396","Parent Géry, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=5695396\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite non polie 3(Madagascar).jpg",{"id":212,"source_url":213,"license_code":148,"credit_html":214,"title":215,"description":216,"author":217,"original_width":218,"original_height":219},63456,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=6989346","Didier Descouens, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=6989346\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labardoritebresil.jpg","Labradorite cut - Brasil - 14x10mm","Didier Descouens",1542,1229,{"id":221,"source_url":222,"license_code":148,"credit_html":223,"title":224,"description":225,"author":226,"original_width":227,"original_height":228},63457,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=9728235","Prokofiev, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=9728235\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","LabradoriteAMD.jpg","Specimen of labradorite from Madagascar. 20cm.","Prokofiev",1533,1384,{"id":230,"source_url":231,"license_code":232,"credit_html":233,"title":234,"description":235,"author":236,"original_width":237,"original_height":238},63458,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=29735120","CC BY 2.0","UCL Mathematical and Physical Sciences c\u002Fo:Mary Hinkley, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=29735120\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite (UCL Geology Collections).jpg","A cut and polished sample of labradorite","UCL Mathematical and Physical Sciences c\u002Fo:Mary Hinkley",3823,2643,{"id":240,"source_url":241,"license_code":158,"credit_html":242,"title":243,"description":244,"author":245,"original_width":246,"original_height":247},63459,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=75162220","Matilde.Spagnolo, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=75162220\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","InCollage 20181218 144029239.jpg","Fenomeno di Labradorescenza in un esemplare di Labradorite presente nella collezione mineralogica dell'Università degli studi di Padova","Matilde.Spagnolo",3413,1920,{"id":249,"source_url":250,"license_code":158,"credit_html":251,"title":252,"description":253,"author":254,"original_width":255,"original_height":179},63461,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=81720207","Matthias Jost, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=81720207\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite wood no filter.jpg","Labtradorite photography in the wood without filter.","Matthias Jost",1080,{"id":257,"source_url":258,"license_code":158,"credit_html":259,"title":260,"description":261,"author":262,"original_width":263,"original_height":264},63463,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88345701","掬茶, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=88345701\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite displayed at Mining Museum of Akita University.jpg","Labradorite displayed at Mining Museum of Akita University","掬茶",2400,1800,{"id":266,"source_url":267,"license_code":158,"credit_html":268,"title":269,"description":270,"author":271,"original_width":272,"original_height":273},63464,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=90630110","Linas Juozėnas, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=90630110\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite crystal.jpg","Labradorite crystal is polished on one side. Many different colors","Linas Juozėnas",6000,4000,{"id":275,"source_url":276,"license_code":232,"credit_html":277,"title":278,"description":279,"author":280,"original_width":273,"original_height":281},33161,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94882655","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94882655\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Anorthosite with labradorite (Wiborg Batholith, 1633 Ma; Kymi Province, Finland) 11.jpg","Anorthosite from the Precambrian of Finland.\n\u003Cp>Anorthosite is a coarsely-crystalline, intrusive igneous rock dominated by plagioclase feldspar.  Pyroxene and other minerals are often present in minor amounts.  Anorthosite is an uncommon rock on Earth, but is abundant on the Moon.\n\u003C\u002Fp>\u003Cp>The sample seen here has very large crystals of labradorite, a type of plagioclase feldspar that often shows a rainbow play of colors.  This comes from a gabbro-anorthosite body in Finland's Wiborg Batholith.  Mineral percentages reported from the intrusion: 81% labradorite, 10% pyroxene, 4% quartz, and 5% other minerals.  I don't see pyroxene in this sample, so I'm calling it anorthosite.  If the specimen had less than 90% labradorite, it would be a gabbroic anorthosite.\n\u003C\u002Fp>\u003Cp>Geologic unit: 1 x 2 square kilometer gabbro-anorthosite body in the central Wiborg Batholith, Baltic Shield\u002FFennoscandian Shield, late Paleoproterozoic, 1.633 Ga\n\u003C\u002Fp>\nLocality: attributed to a quarry at Ylijärvi (= Geological Survey of Finland map 3133, sheet 1, grid coordinates 6740.20-35467.50), ~6 kilometers southwest of Ylämaa village, southern Kymi Province, southern Finland","James St. John",3000,{"id":283,"source_url":284,"license_code":165,"credit_html":285,"title":286,"description":287,"author":288,"original_width":289,"original_height":290},63465,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=153721450","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=153721450\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labrador (spektrolit) - Ylamaa, Finlandia.jpg","Labrador. Ylamaa, Finlandia.","Lech Darski",4571,3047,{"id":292,"source_url":293,"license_code":165,"credit_html":294,"title":295,"description":296,"author":288,"original_width":297,"original_height":298},63466,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=157771066","Lech Darski, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=157771066\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labrador spektrolit - Ylamaa, Finlandia.jpg","Labrador spektrolit - Ylamaa, Finlandia.",3642,2428,{"id":300,"source_url":301,"license_code":232,"credit_html":302,"title":303,"description":279,"author":280,"original_width":304,"original_height":305},80101,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94882645","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94882645\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Anorthosite with labradorite (Wiborg Batholith, 1633 Ma; Kymi Province, Finland) 3.jpg",3932,2617,{"id":307,"source_url":308,"license_code":232,"credit_html":309,"title":310,"description":311,"author":280,"original_width":312,"original_height":313},1373,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94865698","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94865698\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite (Wiborg Batholith, 1633 Ma; Kymi Province, Finland) 3.jpg","Labradorite from the Precambrian of Finland.\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>The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2).  All other silicates have silica + impurities.  Many silicates have a significant percentage of aluminum (the aluminosilicates).\n\u003C\u002Fp>\u003Cp>Feldspar is a group of common silicate minerals.  Feldspars are silicate minerals having one-fourth of all the silicons in SiO2 replaced by aluminum (Si4O8 to (Si3Al)O8).  When this happens, the (Si3Al)O8 has a -1 electric charge.  The charge is satisfied by the addition of one or more metals.  The (Si3Al)O8- structure has relatively large holes, and the only metals that tend to stay in these holes are: K (potassium), Na (sodium), Ca (calcium), Cs (cesium), Ba (barium), Sr (strontium), and Pb (lead).  Of these, K & Na & Ca are the most common metals that enter the matrix.  Sometimes, several different metals enter the structure, resulting in \"garbage can minerals\".\n\u003C\u002Fp>\u003Cp>Chemical analyses of feldspars show that they range in composition from K-feldspar to Na-feldspar and from Na-feldspar to Ca-feldspar.  Mineralogists have thus established two \"families\" of feldspars.  There is no chemical gradient between K-feldspar and Ca-feldspar.\n\u003C\u002Fp>\u003Cp>The sodium- and calcium-feldspars are called plagioclase (\"plag\" for short).  Six different mineral names are available for the plagioclase feldspars: albite, oligoclase, andesine, labradorite, bytownite, and anorthite.  Albite is ~pure sodium feldspar (NaAlSi3O8) and anorthite is ~pure calcium feldspar (CaAl2Si2O8).  The other mentioned minerals are plagioclase feldspars having a mix of sodium and calcium.  The pure end-members are whitish-colored.  The plagioclase feldspars having a mix of sodium and calcium tend to be light gray to dark gray to mottled gray.  Some have a spectacular play of color.\n\u003C\u002Fp>\u003Cp>Seen here is labradorite plagioclase.  It displays iridescent colors when tilted at certain angles to the light - this property is called labradorescence.  Gem-quality samples are called spectrolite.\n\u003C\u002Fp>\u003Cp>The specimen is a partial single crystal from anorthosite, a coarsely-crystalline, intrusive igneous rock dominated by plagioclase feldspar.  Anorthosite is an uncommon rock on Earth, but is abundant on the Moon.  The sample comes from a gabbro-anorthosite body in Finland's Wiborg Batholith.  Mineral percentages reported from the intrusion: 81% labradorite, 10% pyroxene, 4% quartz, and 5% other minerals.\n\u003C\u002Fp>\u003Cp>Geologic unit: 1 x 2 square kilometer gabbro-anorthosite body in the central Wiborg Batholith, Baltic Shield\u002FFennoscandian Shield, late Paleoproterozoic, 1.633 Ga\n\u003C\u002Fp>\u003Cp>Locality: attributed to a quarry at Ylijärvi (= Geological Survey of Finland map 3133, sheet 1, grid coordinates 6740.20-35467.50), ~6 kilometers southwest of Ylämaa village, southern Kymi Province, southern Finland\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of albite:\nwww.mindat.org\u002Fgallery.php?min=96\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of oligoclase:\nwww.mindat.org\u002Fgallery.php?min=2976\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of andesine:\nwww.mindat.org\u002Fgallery.php?min=220\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of labradorite:\nwww.mindat.org\u002Fgallery.php?min=2308\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of bytownite:\nwww.mindat.org\u002Fgallery.php?min=815\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of anorthite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=246",3314,2393,{"id":315,"source_url":316,"license_code":232,"credit_html":317,"title":318,"description":311,"author":280,"original_width":319,"original_height":320},1374,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94865717","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94865717\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite (Wiborg Batholith, 1633 Ma; Kymi Province, Finland) 7.jpg",2918,2596,{"id":322,"source_url":323,"license_code":232,"credit_html":324,"title":325,"description":326,"author":280,"original_width":327,"original_height":328},1376,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=114615081","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=114615081\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite 3.jpg","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 5700 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\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>The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2).  All other silicates have silica + impurities.  Many silicates have a significant percentage of aluminum (the aluminosilicates).\n\u003C\u002Fp>\u003Cp>Feldspar is a group of common silicate minerals.  Feldspars are silicate minerals having one-fourth of all the silicons in SiO2 replaced by aluminum (Si4O8 to (Si3Al)O8).  When this happens, the (Si3Al)O8 has a -1 electric charge.  The charge is satisfied by the addition of one or more metals.  The (Si3Al)O8- structure has relatively large holes, and the only metals that tend to stay in these holes are: K (potassium), Na (sodium), Ca (calcium), Cs (cesium), Ba (barium), Sr (strontium), and Pb (lead).  Of these, K & Na & Ca are the most common metals that enter the matrix.  Sometimes, several different metals enter the structure, resulting in \"garbage can minerals\".\n\u003C\u002Fp>\u003Cp>Chemical analyses of feldspars show that they range in composition from K-feldspar to Na-feldspar and from Na-feldspar to Ca-feldspar.  Mineralogists have thus established two \"families\" of feldspars.  There is no chemical gradient between K-feldspar and Ca-feldspar.\n\u003C\u002Fp>\n\u003Cpre>The sodium- and calcium-feldspars are called plagioclase (\"plag\" for short).  Six different mineral names are available for the plagioclase feldspars: albite, oligoclase, andesine, labradorite, bytownite, and anorthite.  Albite is ~pure sodium feldspar (NaAlSi3O8) and anorthite is ~pure calcium feldspar (CaAl2Si2O8).  The other mentioned minerals are plagioclase feldspars having a mix of sodium and calcium.  The pure end-members are whitish-colored.  The plagioclase feldspars having a mix of sodium and calcium tend to be light gray to dark gray to mottled gray.  Some have a spectacular play of color.\n\u003C\u002Fpre>\n\u003Cp>Seen here is a polished piece of labradorite plagioclase showing iridescent colors.  This property is called labradorescence.  Gem-quality samples are called spectrolite.\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of albite:\nwww.mindat.org\u002Fgallery.php?min=96\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of oligoclase:\nwww.mindat.org\u002Fgallery.php?min=2976\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of andesine:\nwww.mindat.org\u002Fgallery.php?min=220\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of labradorite:\nwww.mindat.org\u002Fgallery.php?min=2308\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of bytownite:\nwww.mindat.org\u002Fgallery.php?min=815\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of anorthite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=246",1832,1530,{"id":330,"source_url":331,"license_code":232,"credit_html":332,"title":333,"description":326,"author":280,"original_width":334,"original_height":335},1377,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=114615082","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=114615082\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite 1.jpg",1846,1514,{"id":337,"source_url":338,"license_code":232,"credit_html":339,"title":340,"description":326,"author":280,"original_width":341,"original_height":342},1378,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=114615087","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=114615087\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite 4.jpg",1768,1492,{"id":344,"source_url":345,"license_code":232,"credit_html":346,"title":347,"description":326,"author":280,"original_width":348,"original_height":349},1379,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=114615088","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=114615088\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite 5.jpg",1467,1868,{"id":351,"source_url":352,"license_code":353,"credit_html":354,"title":355,"description":356,"author":357,"original_width":358,"original_height":359},12052,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=163484576","CC0 1.0","Shannon Heinle, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=163484576\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Hypersthene with labradorite (GeoDIL number - 1624).jpg","Hypersthene is a member of the Pyroxene Group. Its chemical formula is (Mg,Fe)SiO3. Hypersthene is a relatively common mineral and is found in igneous and some metamorphic rocks, as well as meteorites. The name comes from the Greek, hyper, meaning “above” and stenos, meaning “power”. This sample is about 4 cm.","Shannon Heinle",2386,1801,{"id":361,"source_url":362,"license_code":158,"credit_html":363,"title":364,"description":365,"author":366,"original_width":367,"original_height":368},33139,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=42244959","Eunostos, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=42244959\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Anorthite labradorite et opale.JPG","Anorthite labradorite (à gauche) et opale (à droite). L'anorthite labradorite vient du Labrador, au Canada, et fait partie de l'ancienne collection Vésignié. L'opale vient de Coober Pedy, en Australie méridionale, et est un don de M. Schubnel. Galerie de Minéralogie et de Géologie du Muséum national d'histoire naturelle, à Paris, en France.","Eunostos",1632,1224,{"id":370,"source_url":371,"license_code":232,"credit_html":372,"title":373,"description":374,"author":280,"original_width":375,"original_height":376},37838,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94882457","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94882457\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Anorthosite (\"Blue Eyes Granite\") (Nain Anorthosite, Mesoproterozoic, 1.29-1.35 Ga; Ten Mile Bay Quarry, Labrador, Canada) 3.jpg","\"Blue Eyes Granite\" - coarsely-crystalline anorthosite from the Precambrian of Canada.\n\u003Cp>Anorthosites are uncommon intrusive igneous rocks almost exclusively composed of Ca-rich plagioclase feldspar.  There’s usually a blackish pyroxene component as well.  Anorthosites having labradorite plagioclase feldspar will display a wonderfully colorful iridescent play of colors (labradorescence).  This makes them desirable decorative stones.\n\u003C\u002Fp>\nAll of the lightish to darkish gray material in the polished decorative stone surface shown above is labradorite - every crystal will flash bright blue when tilted at the correct angle in the light.  This expensive decorative stone comes from the Ten Mile Bay Quarry, near the town of Nain along the Labrador coast, eastern Canada.  The quarry exploits the Nain Anorthosite (Nain Plutonic Suite), a mid-Mesoproterozoic intrusion (1.29 to 1.35 billion years) emplaced along the Abloviak Shear Zone.",2538,2599,{"id":378,"source_url":379,"license_code":232,"credit_html":380,"title":381,"description":374,"author":280,"original_width":382,"original_height":383},37839,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94882463","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94882463\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Anorthosite (\"Blue Eyes Granite\") (Nain Anorthosite, Mesoproterozoic, 1.29-1.35 Ga; Ten Mile Bay Quarry, Labrador, Canada) 8.jpg",2384,2323,{"id":385,"source_url":386,"license_code":232,"credit_html":387,"title":388,"description":374,"author":280,"original_width":389,"original_height":390},37840,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94882482","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94882482\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Anorthosite (\"Blue Eyes Granite\") (Nain Anorthosite, Mesoproterozoic, 1.29-1.35 Ga; Ten Mile Bay Quarry, Labrador, Canada) 12.jpg",3553,4430,{"id":392,"source_url":393,"license_code":232,"credit_html":394,"title":395,"description":311,"author":280,"original_width":396,"original_height":397},71256,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94865712","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94865712\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite (Wiborg Batholith, 1633 Ma; Kymi Province, Finland) 1.jpg",3499,2438,{"id":399,"source_url":400,"license_code":232,"credit_html":401,"title":402,"description":403,"author":280,"original_width":404,"original_height":405},71258,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474391","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474391\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite plagioclase feldspar (Nain Anorthosite, Mesoproterozoic, 1.29-1.35 Ga; Nain, Labrador, Canada) 4.jpg","Plagioclase feldspar from the Precambrian of Canada.\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 5800 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>The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2).  All other silicates have silica + impurities.  Many silicates have a significant percentage of aluminum (the aluminosilicates).\n\u003C\u002Fp>\u003Cp>Feldspar is a group of common silicate minerals.  Feldspars are silicate minerals having one-fourth of all the silicons in SiO2 replaced by aluminum (Si4O8 to (Si3Al)O8).  When this happens, the (Si3Al)O8 has a -1 electric charge.  The charge is satisfied by the addition of one or more metals.  The (Si3Al)O8- structure has relatively large holes, and the only metals that tend to stay in these holes are: K (potassium), Na (sodium), Ca (calcium), Cs (cesium), Ba (barium), Sr (strontium), and Pb (lead).  Of these, K & Na & Ca are the most common metals that enter the matrix.  Sometimes, several different metals enter the structure, resulting in \"garbage can minerals\".\n\u003C\u002Fp>\u003Cp>Chemical analyses of feldspars show that they range in composition from K-feldspar to Na-feldspar and from Na-feldspar to Ca-feldspar.  Mineralogists have thus established two \"families\" of feldspars.  There is no chemical gradient between K-feldspar and Ca-feldspar.\n\u003C\u002Fp>\u003Cp>The sodium- to calcium-feldspars are called plagioclase (\"plag\" for short).  Six different mineral names are available for the plagioclase feldspars: albite, oligoclase, andesine, labradorite, bytownite, and anorthite.  Albite is ~pure sodium feldspar (NaAlSi3O8) and anorthite is ~pure calcium feldspar (CaAl2Si2O8).  The other mentioned minerals are plagioclase feldspars having a mix of sodium and calcium.  The pure end-members are whitish-colored.  The plagioclase feldspars having a mix of sodium and calcium tend to be light gray to dark gray to mottled gray.  Some have a spectacular play of color.\n\u003C\u002Fp>\u003Cp>Plagioclase has a nonmetallic luster, a white to light gray to dark color, a white streak, a hardness of 6 on the Mohs Hardness Scale, and breaks along two cleavage planes meeting at 90 degrees.  Cleavage planes often show striations (= very thin, straight, parallel grooves).\n\u003C\u002Fp>\u003Cp>Seen here is a piece of labradorite plagioclase feldspar from the Nain Anorthosite in eastern Canada.  Anorthosites are uncommon intrusive igneous rocks almost exclusively composed of plagioclase feldspar.  There’s usually a blackish pyroxene component as well.  Some famous anorthosite occurrences include Wyoming's Laramie Range, New York State's Adirondacks Mountains, and the Moon.\n\u003C\u002Fp>\u003Cp>Geologic unit: Nain Anorthosite (Nain Plutonic Suite), mid-Mesoproterozoic, 1.29 to 1.35 Ga\n\u003C\u002Fp>\u003Cp>Locality: unrecorded site at or near the town of Nain (possibly a quarry), coastal Labrador, eastern Canada\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of labradorite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=2308",1968,2245,{"id":407,"source_url":408,"license_code":232,"credit_html":409,"title":410,"description":403,"author":280,"original_width":411,"original_height":412},71259,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474395","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474395\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite plagioclase feldspar (Nain Anorthosite, Mesoproterozoic, 1.29-1.35 Ga; Nain, Labrador, Canada) 3.jpg",2035,1268,{"id":414,"source_url":415,"license_code":232,"credit_html":416,"title":417,"description":418,"author":280,"original_width":419,"original_height":420},71262,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94865711","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=94865711\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite (Wiborg Batholith, 1633 Ma; Kymi Province, Finland) 5.jpg","Labradorite from the Precambrian of Finland.\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>The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2).  All other silicates have silica + impurities.  Many silicates have a significant percentage of aluminum (the aluminosilicates).\n\u003C\u002Fp>\u003Cp>Feldspar is a group of common silicate minerals.  Feldspars are silicate minerals having one-fourth of all the silicons in SiO2 replaced by aluminum (Si4O8 to (Si3Al)O8).  When this happens, the (Si3Al)O8 has a -1 electric charge.  The charge is satisfied by the addition of one or more metals.  The (Si3Al)O8- structure has relatively large holes, and the only metals that tend to stay in these holes are: K (potassium), Na (sodium), Ca (calcium), Cs (cesium), Ba (barium), Sr (strontium), and Pb (lead).  Of these, K & Na & Ca are the most common metals that enter the matrix.  Sometimes, several different metals enter the structure, resulting in \"garbage can minerals\".\n\u003C\u002Fp>\u003Cp>Chemical analyses of feldspars show that they range in composition from K-feldspar to Na-feldspar and from Na-feldspar to Ca-feldspar.  Mineralogists have thus established two \"families\" of feldspars.  There is no chemical gradient between K-feldspar and Ca-feldspar.\n\u003C\u002Fp>\u003Cp>The sodium- and calcium-feldspars are called plagioclase (\"plag\" for short).  Six different mineral names are available for the plagioclase feldspars: albite, oligoclase, andesine, labradorite, bytownite, and anorthite.  Albite is ~pure sodium feldspar (NaAlSi3O8) and anorthite is ~pure calcium feldspar (CaAl2Si2O8).  The other mentioned minerals are plagioclase feldspars having a mix of sodium and calcium.  The pure end-members are whitish-colored.  The plagioclase feldspars having a mix of sodium and calcium tend to be light gray to dark gray to mottled gray.  Some have a spectacular play of color.\n\u003C\u002Fp>\u003Cp>Seen here is labradorite plagioclase.  It displays iridescent colors when tilted at certain angles to the light (in this case, deep electric blue) - this property is called labradorescence.  Gem-quality samples are called spectrolite.\n\u003C\u002Fp>\u003Cp>The specimen is a partial single crystal from anorthosite, a coarsely-crystalline, intrusive igneous rock dominated by plagioclase feldspar.  Anorthosite is an uncommon rock on Earth, but is abundant on the Moon.  The sample comes from a gabbro-anorthosite body in Finland's Wiborg Batholith.  Mineral percentages reported from the intrusion: 81% labradorite, 10% pyroxene, 4% quartz, and 5% other minerals.\n\u003C\u002Fp>\u003Cp>Geologic unit: 1 x 2 square kilometer gabbro-anorthosite body in the central Wiborg Batholith, Baltic Shield\u002FFennoscandian Shield, late Paleoproterozoic, 1.633 Ga\n\u003C\u002Fp>\u003Cp>Locality: attributed to a quarry at Ylijärvi (= Geological Survey of Finland map 3133, sheet 1, grid coordinates 6740.20-35467.50), ~6 kilometers southwest of Ylämaa village, southern Kymi Province, southern Finland\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of albite:\nwww.mindat.org\u002Fgallery.php?min=96\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of oligoclase:\nwww.mindat.org\u002Fgallery.php?min=2976\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of andesine:\nwww.mindat.org\u002Fgallery.php?min=220\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of labradorite:\nwww.mindat.org\u002Fgallery.php?min=2308\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of bytownite:\nwww.mindat.org\u002Fgallery.php?min=815\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of anorthite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=246",2828,1424,{"id":422,"source_url":423,"license_code":232,"credit_html":424,"title":425,"description":403,"author":280,"original_width":426,"original_height":427},71265,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474378","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474378\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite plagioclase feldspar (Nain Anorthosite, Mesoproterozoic, 1.29-1.35 Ga; Nain, Labrador, Canada) 13.jpg",1755,1763,{"id":429,"source_url":430,"license_code":232,"credit_html":431,"title":432,"description":433,"author":280,"original_width":434,"original_height":435},71266,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474381","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474381\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite plagioclase feldspar (Nain Anorthosite, Mesoproterozoic, 1.29-1.35 Ga; Nain, Labrador, Canada) 11.jpg","Cleavage plane striations on plagioclase feldspar from the Precambrian of Canada.\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 5800 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>The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2).  All other silicates have silica + impurities.  Many silicates have a significant percentage of aluminum (the aluminosilicates).\n\u003C\u002Fp>\u003Cp>Feldspar is a group of common silicate minerals.  Feldspars are silicate minerals having one-fourth of all the silicons in SiO2 replaced by aluminum (Si4O8 to (Si3Al)O8).  When this happens, the (Si3Al)O8 has a -1 electric charge.  The charge is satisfied by the addition of one or more metals.  The (Si3Al)O8- structure has relatively large holes, and the only metals that tend to stay in these holes are: K (potassium), Na (sodium), Ca (calcium), Cs (cesium), Ba (barium), Sr (strontium), and Pb (lead).  Of these, K & Na & Ca are the most common metals that enter the matrix.  Sometimes, several different metals enter the structure, resulting in \"garbage can minerals\".\n\u003C\u002Fp>\u003Cp>Chemical analyses of feldspars show that they range in composition from K-feldspar to Na-feldspar and from Na-feldspar to Ca-feldspar.  Mineralogists have thus established two \"families\" of feldspars.  There is no chemical gradient between K-feldspar and Ca-feldspar.\n\u003C\u002Fp>\u003Cp>The sodium- to calcium-feldspars are called plagioclase (\"plag\" for short).  Six different mineral names are available for the plagioclase feldspars: albite, oligoclase, andesine, labradorite, bytownite, and anorthite.  Albite is ~pure sodium feldspar (NaAlSi3O8) and anorthite is ~pure calcium feldspar (CaAl2Si2O8).  The other mentioned minerals are plagioclase feldspars having a mix of sodium and calcium.  The pure end-members are whitish-colored.  The plagioclase feldspars having a mix of sodium and calcium tend to be light gray to dark gray to mottled gray.  Some have a spectacular play of color.\n\u003C\u002Fp>\u003Cp>Plagioclase has a nonmetallic luster, a white to light gray to dark color, a white streak, a hardness of 6 on the Mohs Hardness Scale, and breaks along two cleavage planes meeting at 90 degrees.  Cleavage planes often show striations (= very thin, straight, parallel grooves).\n\u003C\u002Fp>\u003Cp>Seen here is a piece of labradorite plagioclase feldspar from the Nain Anorthosite in eastern Canada.  Anorthosites are uncommon intrusive igneous rocks almost exclusively composed of plagioclase feldspar.  There’s usually a blackish pyroxene component as well.  Some famous anorthosite occurrences include Wyoming's Laramie Range, New York State's Adirondacks Mountains, and the Moon.\n\u003C\u002Fp>\u003Cp>Geologic unit: Nain Anorthosite (Nain Plutonic Suite), mid-Mesoproterozoic, 1.29 to 1.35 Ga\n\u003C\u002Fp>\u003Cp>Locality: unrecorded site at or near the town of Nain (possibly a quarry), coastal Labrador, eastern Canada\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of labradorite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=2308",1963,1803,{"id":437,"source_url":438,"license_code":232,"credit_html":439,"title":440,"description":403,"author":280,"original_width":441,"original_height":442},71267,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474390","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474390\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite plagioclase feldspar (Nain Anorthosite, Mesoproterozoic, 1.29-1.35 Ga; Nain, Labrador, Canada) 5.jpg",1863,1628,{"id":444,"source_url":445,"license_code":232,"credit_html":446,"title":447,"description":448,"author":280,"original_width":449,"original_height":450},71268,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474392","James St. John, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=128474392\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Labradorite plagioclase feldspar (Nain Anorthosite, Mesoproterozoic, 1.29-1.35 Ga; Nain, Labrador, Canada) 6.jpg","Plagioclase feldspar from the Precambrian of Canada.\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 5800 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>The simplest & most abundant silicate mineral in the Earth's crust is quartz (SiO2).  All other silicates have silica + impurities.  Many silicates have a significant percentage of aluminum (the aluminosilicates).\n\u003C\u002Fp>\u003Cp>Feldspar is a group of common silicate minerals.  Feldspars are silicate minerals having one-fourth of all the silicons in SiO2 replaced by aluminum (Si4O8 to (Si3Al)O8).  When this happens, the (Si3Al)O8 has a -1 electric charge.  The charge is satisfied by the addition of one or more metals.  The (Si3Al)O8- structure has relatively large holes, and the only metals that tend to stay in these holes are: K (potassium), Na (sodium), Ca (calcium), Cs (cesium), Ba (barium), Sr (strontium), and Pb (lead).  Of these, K & Na & Ca are the most common metals that enter the matrix.  Sometimes, several different metals enter the structure, resulting in \"garbage can minerals\".\n\u003C\u002Fp>\u003Cp>Chemical analyses of feldspars show that they range in composition from K-feldspar to Na-feldspar and from Na-feldspar to Ca-feldspar.  Mineralogists have thus established two \"families\" of feldspars.  There is no chemical gradient between K-feldspar and Ca-feldspar.\n\u003C\u002Fp>\u003Cp>The sodium- to calcium-feldspars are called plagioclase (\"plag\" for short).  Six different mineral names are available for the plagioclase feldspars: albite, oligoclase, andesine, labradorite, bytownite, and anorthite.  Albite is ~pure sodium feldspar (NaAlSi3O8) and anorthite is ~pure calcium feldspar (CaAl2Si2O8).  The other mentioned minerals are plagioclase feldspars having a mix of sodium and calcium.  The pure end-members are whitish-colored.  The plagioclase feldspars having a mix of sodium and calcium tend to be light gray to dark gray to mottled gray.  Some have a spectacular play of color (hints of that can be seen here).\n\u003C\u002Fp>\u003Cp>Plagioclase has a nonmetallic luster, a white to light gray to dark color, a white streak, a hardness of 6 on the Mohs Hardness Scale, and breaks along two cleavage planes meeting at 90 degrees.  Cleavage planes often show striations (= very thin, straight, parallel grooves).\n\u003C\u002Fp>\u003Cp>Seen here is a piece of labradorite plagioclase feldspar from the Nain Anorthosite in eastern Canada.  Anorthosites are uncommon intrusive igneous rocks almost exclusively composed of plagioclase feldspar.  There’s usually a blackish pyroxene component as well.  Some famous anorthosite occurrences include Wyoming's Laramie Range, New York State's Adirondacks Mountains, and the Moon.\n\u003C\u002Fp>\u003Cp>Geologic unit: Nain Anorthosite (Nain Plutonic Suite), mid-Mesoproterozoic, 1.29 to 1.35 Ga\n\u003C\u002Fp>\u003Cp>Locality: unrecorded site at or near the town of Nain (possibly a quarry), coastal Labrador, eastern Canada\n\u003C\u002Fp>\n\u003Chr>\n\u003Cp>Photo gallery of labradorite:\n\u003C\u002Fp>\nwww.mindat.org\u002Fgallery.php?min=2308",1910,1953,[452,459,464,469,474],{"id":453,"url":454,"label":455,"formula":456,"spacegroup":457,"year":458},7398,"\u002Fcif\u002F7398.cif","Wenk 1980 · Ca.325 Na.16 (Si1.19 Al.81) O4","Ca.325 Na.16 (Si1.19 Al.81) O4","C -1",1980,{"id":460,"url":461,"label":462,"formula":463,"spacegroup":457,"year":458},7400,"\u002Fcif\u002F7400.cif","Wenk 1980 · Ca.317 Na.183 Si1.174 Al.824 O4","Ca.317 Na.183 Si1.174 Al.824 O4",{"id":465,"url":466,"label":467,"formula":468,"spacegroup":457,"year":458},7401,"\u002Fcif\u002F7401.cif","Wenk 1980 · Ca.325 Na.175 Si1.174 Al.824 O4","Ca.325 Na.175 Si1.174 Al.824 O4",{"id":470,"url":471,"label":472,"formula":473,"spacegroup":457,"year":458},7402,"\u002Fcif\u002F7402.cif","Wenk 1980 · Ca.32 Na.18 Si1.184 Al.814 O4","Ca.32 Na.18 Si1.184 Al.814 O4",{"id":475,"url":476,"label":477,"formula":478,"spacegroup":457,"year":458},7403,"\u002Fcif\u002F7403.cif","Wenk 1980 · Ca.34 Na.15 (Si1.17 Al.83) O4","Ca.34 Na.15 (Si1.17 Al.83) O4",[480,481,482,483,484,485,486,487,488,489,490,491,492,493,494,495,496,497,498,499,500,501,502,503,504],"Black Moonstone","Carnatit","Carnatita","Carnatite","Labrador","Labrador Feldspar","Labrador Moonstone","Labradoriet","Labradoriitti","Labradorit","Labradorita","Labradoritas","Mauilit","Mauilita","Mauilite","Opaline Feldspar","Radauit","Radauita","Radauite","Silicit","Silicita","Silicite","Spectrolita","Spectrolith","Spektrolith",[],{"history":8,"applications":8}]