[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"minerals:one:7688":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":8,"ima_formula":8,"elements":15,"sigelements":20,"key_elements":8,"impurities":8,"cim":8,"ima_status":8,"ima_notes":8,"ima_history":8,"approval_year":8,"publication_year":8,"discovery_year":21,"strunz10ed1":22,"strunz10ed2":22,"strunz10ed3":22,"strunz10ed4":8,"dana8ed1":22,"dana8ed2":22,"dana8ed3":22,"dana8ed4":22,"csystem":23,"cclass":8,"spacegroup":8,"spacegroupset":22,"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":24,"tlform":8,"hmin":25,"hmax":26,"hardtype":8,"vhnmin":22,"vhnmax":22,"vhnerror":8,"vhng":8,"vhns":8,"commenthard":8,"dmeas":27,"dmeas2":22,"dcalc":22,"dmeaserror":8,"dcalcerror":8,"commentdense":8,"lustre":8,"lustretype":28,"commentluster":8,"diapheny":29,"streak":8,"colour":30,"commentcolor":8,"colors":31,"streak_colors":8,"luminescence":8,"uv":35,"cleavage":8,"cleavagetype":36,"fracturetype":8,"tenacity":37,"commentbreak":8,"opticaltype":8,"opticalsign":8,"opticalalpha":8,"opticalalpha2":22,"opticalalphaerror":8,"opticalbeta":8,"opticalbeta2":22,"opticalbetaerror":8,"opticalgamma":8,"opticalgamma2":22,"opticalgammaerror":8,"opticalomega":8,"opticalomega2":22,"opticalomegaerror":8,"opticalepsilon":8,"opticalepsilon2":22,"opticalepsilonerror":8,"opticaln":8,"opticaln2":8,"opticalnerror":8,"optical2vcalc":8,"optical2vcalc2":8,"optical2vcalcerror":8,"optical2vmeasured":8,"optical2vmeasured2":8,"optical2vmeasurederror":8,"rimin":8,"rimax":8,"opticaldispersion":8,"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":38,"thermalbehaviour":8,"other":8,"industrial":8,"occurrence":39,"otheroccurrence":8,"type_specimen_store":8,"description_short":8,"aboutname":40,"rock_parent":8,"rock_parent2":8,"rock_root":41,"rock_bgs_code":8,"meteoritical_code":8,"updttime":42,"reviewed_at":8,"variety_of":43,"varieties":48,"group_members":49,"associates":50,"confused_with":59,"type_localities":60,"occurrence_total":67,"citations":68,"images":84,"structures":225,"synonyms":226,"language_names":232,"wikidata_qid":8,"texts":233},7688,"1:1:7688:9","32e8125d-fb3d-472e-b61c-4e5599f4db2a","Cleavelandite",null,2,"variety",96,17638,false,"Na(AlSi\u003Csub>3\u003C\u002Fsub>O\u003Csub>8\u003C\u002Fsub>)",[16,17,18,19],"Al","Na","Si","O",[16,17,18,19],"1817","0","Triclinic","Platy",6,6.5,"2.6","Sub-Adamantine,Vitreous,Sub-Vitreous","Translucent,Opaque","White, Tan, Blue",[32,33,34],"white","brown","blue","Frequent fluoresces red SWUV","Perfect","brittle","Non-Magnetic","Granite pegmatites, Late-stage vugs in granite","Named in 1823 by Henry J. Brooke in honor of Parker Cleaveland [January 15, 1780 Rowley (Byfield), Massachusetts, USA - August 15, 1858, in Brunswick, Maine, USA], professor of geology and mineralogy at Bowdoin College in Maine 1805-1858. In 1816 Cleaveland wrote the first mineralogy textbook authored by a citizen of the USA. Despite the title page date, the textbook was actually released in January 1817. The textbook was noted for its unification of European schools of thought and was also popular in its second edition of 1822.\u003Cem> Cleavelandite had been described earlier in 1817 by Johann Friedrich Ludwig Hausmann with the name \"kieselspath\".\u003C\u002Fem> In 1815, Hans Peter Eggertz named granular and radiated albite, probably identical to cleavelandite of Brooke. In 1936, Harold Lattimore Alling defined cleavelandite as a triclinic mineral, suggesting a difference from true albite as well as \"analbite\". Fisher (1968) studied cleavelandite from Chesterfield, Massachusetts, USA, the type locality, but did not study type specimens, and proposed that true cleavelandite should be restricted to warped platy masses of mineral with lamellae parallel to (010) and \"lack other well-defined crystal faces, and may be twinned on the albite law\". This definition would not include most specimens called \"cleavelandite\", especially those cleavelandites grown into open cavities, although such \"cleavelandite\" is also known from the type locality. The current use of the varietal name generally includes cavity hosted crystal aggregates.\r\n\r\nThe original annoncement of Cleavelandite was published in \u003Cem>Annals of Philosophy,\u003C\u002Fem> May 1823, p. 381-382:\r\n\r\n\u003Cstrong>Article XII.\u003C\u002Fstrong> \u003Cem>A Description of the Crystalline Form of some new Minerals.\u003C\u002Fem> By H. J. Brooke, Esq. FRS. FLS. &c. (To the Editor of the Annals of Philosophy.)\r\n\r\nDear SIR, April 19, 1822.\r\n\tHaving lately been engaged in an examination of the crystalline forms of minerals, and in a few instances of their chemical characters, preparatory to a list I have proposed to add to an elementary production to crystallography, I have observed a few new results, which form the substance of the following brief notices: ...\r\n\u003Cem>Cleavelandite.\u003C\u002Fem> - The \u003Cem>albite,\u003C\u002Fem> and \u003Cem>siliceous spar\u003C\u002Fem> of Haussman [sic], which accompanies the green and red tourmaline from Chesterfield, in Massachusetts, are varieties of the same mineral. Two different names having been given to this substance, it becomes necessary either to adopt one of these to the exclusion of the other, or to assign a new one to the species.\r\n\tAs \u003Cem>albite\u003C\u002Fem> is generally \u003Cem>blue\u003C\u002Fem>, and sometimes \u003Cem>red,*\u003C\u002Fem> its name is consequently bad, and \u003Cem>siliceous spar\u003C\u002Fem> might be applied with equal propriety to the other substances; I have therefore, preferred adopting the term \u003Cem>Cleavelandite\u003C\u002Fem> to denote the species, out of respect to the Professor of Natural Philosophy in Bowdoin College. United States.\r\n\tThis species has cleavages in three directions, parallel to the planes of a doubly oblique prism.\r\n\r\n* The specimen which first enabled me to determine the form is bright blue. It came from Labrador, and was given to me by the Rev. C. I. Latrobe. M. Nordenskiold has favored me with a specimen which is red.",0,"2025-08-11 12:14:28",{"id":11,"name":44,"entrytype":41,"csystem":23,"ima_formula":14,"mindat_formula":14,"hmin":25,"hmax":26,"dmeas":27,"dcalc":45,"strunz10ed1":46,"primary_image_id":47},"Albite","2.615","9",549,[],[],[51],{"id":52,"name":53,"entrytype":41,"csystem":54,"ima_formula":55,"mindat_formula":55,"hmin":26,"hmax":26,"dmeas":56,"dcalc":57,"primary_image_id":58},1419,"Eucryptite","Trigonal","LiAlSiO\u003Csub>4\u003C\u002Fsub>","2.657","2.654",8164,[],[61],{"id":62,"txt":63,"latitude":64,"longitude":65,"country":66},5971,"Clark Ledge pegmatite locality, Chesterfield, Hampshire County, Massachusetts, USA",42.4205703,-72.8923977,"USA",587,[69,72,76,80],{"id":70,"year":8,"html":71,"doi":8},16131637,"Manual of Mineralogy after James D. Dana, 1977, by C. Klein & C.S. Hurlbut, Jr.",{"id":73,"year":74,"html":75,"doi":8},16607693,1994,"King, Vandall T., Foord, Eugene E. (1994) \u003Ci>Mineralogy of Maine\u003C\u002Fi> Vol. 1 - Descriptive mineralogy. Maine Geological Survey.",{"id":77,"year":78,"html":79,"doi":8},1118654,1997,"Gaines, Richard V.; Skinner, H. Catherine W.; Foord, Eugene E.; Mason, Brian; Rosenzweig, Abraham; King, Vandall T. (1997) \u003Ci>Dana's New Mineralogy\u003C\u002Fi> (8th ed.). Wiley-Interscience. 1872 pp.",{"id":81,"year":82,"html":83,"doi":8},16607694,2000,"King, Vandall T. (2000) \u003Ci>Mineralogy of Maine\u003C\u002Fi> Vol. 2 - Mining History, Gems, and Geology. Maine Geological Survey.",[85,94,104,113,123,133,143,150,156,162,169,175,184,192,198,204,211,218],{"id":86,"source_url":87,"license_code":88,"credit_html":89,"title":90,"description":91,"author":92,"original_width":93,"original_height":93},31843,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=86703474","CC BY 4.0","Marie-Lan Taÿ Pamart, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=86703474\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Cleavelandite Navegadora MNHN Minéralogie.jpg","Albite (cleavelandite) from Navegadora, Brazil. Gallery of Mineralogy and Geology of the French National Museum of Natural History in Paris.","Marie-Lan Taÿ Pamart",5000,{"id":95,"source_url":96,"license_code":97,"credit_html":98,"title":99,"description":100,"author":101,"original_width":102,"original_height":103},9502,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=39743632","CC BY-SA 4.0","Géry PARENT, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=39743632\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Scapolite, elbaïte, cleavelandite 7100.1.2830.jpg","scapolite, tourmaline var. elbaite, albite var. cleavelandite : Badakhshan Province (Badakshan Province ; Badahsan Province), Afghanistan","Géry PARENT",1988,1325,{"id":105,"source_url":106,"license_code":97,"credit_html":107,"title":108,"description":109,"author":110,"original_width":111,"original_height":112},49487,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=132610876","Eric Polk, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=132610876\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Albite var Cleavelandite with Quartz NHMLA.png","Sample of Cleavelandite with Quartz collected from Peaerneira Mine, Minas Gerais, Brazil.  On display at the Natural History Museum of Los Angeles County, Los Angeles, California, USA.","Eric Polk",1817,1302,{"id":114,"source_url":115,"license_code":116,"credit_html":117,"title":118,"description":119,"author":120,"original_width":121,"original_height":122},6846,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=80477573","Public domain","Petr Gadas, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=80477573\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Darrellhenryite-Albite (Var. Cleavelandite)-719375.jpg","\u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FDarrellhenryite\" class=\"extiw\" title=\"en:Darrellhenryite\">Darrellhenryite\u003C\u002Fa>, \u003Ca href=\"https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAlbite\" class=\"extiw\" title=\"en:Albite\">Albite\u003C\u002Fa> (Var. Cleavelandite)\n\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>\u003Cdl>\u003Cdd>\u003Ci>Dimensions:\u003C\u002Fi> 69 mm x 51 mm x 34 mm\u003C\u002Fdd>\n\u003Cdd>\u003Ci>Locality:\u003C\u002Fi> Nová Ves, Český Krumlov District, South Bohemian Region, Czech Republic\u003C\u002Fdd>\n\u003Cdd>\u003Ci>Description:\u003C\u002Fi> Pink crystals of darrellhenryite up to 32mm typicaly in cleavelandite-rich matrix. Personal collection of PG.\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>\u003C\u002Fdd>\u003C\u002Fdl>","Petr Gadas",1231,895,{"id":124,"source_url":125,"license_code":126,"credit_html":127,"title":128,"description":129,"author":130,"original_width":131,"original_height":132},23930,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=22204358","CC BY-SA 3.0","Parent Géry, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=22204358\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Topaze, phlogopite, cleavelandite.jpeg","crystals of topaz, crystals of mica var. phlogopite, crystals of albite var. cleavelandite : Ghundao hill, Katlang, Mardan District, Khyber Pakhtunkhwa (North-West Frontier Province), Pakistan","Parent Géry",3825,2848,{"id":134,"source_url":135,"license_code":136,"credit_html":137,"title":138,"description":139,"author":140,"original_width":141,"original_height":142},54186,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=118199282","CC BY-SA 2.0","Pacific Museum of Earth from Canada, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=118199282\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Fairfieldite with Cleavelandite, Triphylite, and Vivianite (48522507171).jpg","Unknown description\u003Cspan style=\"display: none;\">Unknown description\u003C\u002Fspan>","Pacific Museum of Earth from Canada",6000,4000,{"id":144,"source_url":145,"license_code":126,"credit_html":146,"title":147,"description":148,"author":130,"original_width":149,"original_height":132},57197,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=24582601","Parent Géry, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=24582601\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Morganite, goshénite, cleavelandite, quartz 1.jpeg","beryl var. morganite, beryl var. goshenite, albite var. cleavelandite, quartz : Chamachhu Pegmatites, Chamachhu, Haramosh Mts, Skardu District, Baltistan, Gilgit-Baltistan (Northern Areas), Pakistan",4217,{"id":151,"source_url":152,"license_code":126,"credit_html":153,"title":154,"description":148,"author":130,"original_width":155,"original_height":132},57198,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=24582610","Parent Géry, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=24582610\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Morganite, goshénite, cleavelandite, quartz.jpeg",4288,{"id":157,"source_url":158,"license_code":126,"credit_html":159,"title":160,"description":161,"author":130,"original_width":155,"original_height":132},59185,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=23698120","Parent Géry, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=23698120\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Hiddenite, cleavelandite, quartz 1.jpeg","crystals of spodumene var. hiddenite, crystals of albite var. cleavelandite, crystals of smoky quartz : Paprok Mine (Papruk Mine ; Paprowk Mine), Kamdesh District, Nuristan Province (Nurestan Province ; Nooristan Province ; Nuristan), Afghanistan",{"id":163,"source_url":164,"license_code":126,"credit_html":165,"title":166,"description":161,"author":130,"original_width":167,"original_height":168},59186,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=23698121","Parent Géry, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=23698121\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Hiddénite, cleavelandite, quartz 2.jpeg",3606,2767,{"id":170,"source_url":171,"license_code":126,"credit_html":172,"title":173,"description":161,"author":130,"original_width":174,"original_height":132},59187,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=23698122","Parent Géry, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=23698122\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Hiddénite, cleavelandite, quartz 3.jpeg",3899,{"id":176,"source_url":177,"license_code":178,"credit_html":179,"title":180,"description":181,"author":101,"original_width":182,"original_height":183},60731,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=12525543","CC0 1.0","Géry PARENT, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=12525543\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Tourmaline, feldspar.jpg","tourmaline var. indicolite, feldspar var. cleavelandite : Sabsar (Supsar ; Sapsir ; Sabsir ; Sabsan ; Subsar), Haramosh Mts., Skardu District, Baltistan, Gilgit-Baltistan (Northern Areas), Pakistan",2657,3924,{"id":185,"source_url":186,"license_code":97,"credit_html":187,"title":188,"description":189,"author":101,"original_width":190,"original_height":191},68621,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=44575508","Géry PARENT, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=44575508\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Morganite, cleavelandite, schorl, quartz, lazurite 7100.4914.jpg","beryl var. morganite, albite var. cleavelandite, tourmaline var. schorl, quartz, lazurite : Kunar Mine, Kunar Valley, Konar Province (Kunar Province, Konarh Province, Konarha Province),  Afghanistan",1996,1517,{"id":193,"source_url":194,"license_code":97,"credit_html":195,"title":196,"description":189,"author":101,"original_width":74,"original_height":197},68622,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=44575510","Géry PARENT, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=44575510\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Morganite, cleavelandite, schorl, quartz, lazurite 7100.4919.jpg",1344,{"id":199,"source_url":200,"license_code":126,"credit_html":201,"title":202,"description":203,"author":130,"original_width":155,"original_height":132},71904,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=21138892","Parent Géry, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=21138892\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Lépidolite, cleavelandite, orthose, elbaïte 3.jpg","cristaux de mica var. lépidolite, cristaux d'albite var. cleavelandite, cristaux de feldspath var. orthose, cristaux de tourmaline var. elbaïte : Itatiala Mine, Conselheiro Pena, Doce valley, Minas Gerais, Brazil",{"id":205,"source_url":206,"license_code":97,"credit_html":207,"title":208,"description":209,"author":101,"original_width":102,"original_height":210},80426,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=44575515","Géry PARENT, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=44575515\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Muscovite, cleavelandite 7100.0649.jpg","mica var. star-muscovite, albite var. cleavelandite : Linópolis, Divino das Laranjeiras, Doce valley, Minas Gerais, Brazil",1326,{"id":212,"source_url":213,"license_code":97,"credit_html":214,"title":215,"description":209,"author":101,"original_width":216,"original_height":217},80427,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=44575516","Géry PARENT, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=44575516\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Muscovite, cleavelandite 7100.0652.jpg",1970,1412,{"id":219,"source_url":220,"license_code":97,"credit_html":221,"title":222,"description":209,"author":101,"original_width":223,"original_height":224},80428,"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=44575517","Géry PARENT, via \u003Ca href=\"https:\u002F\u002Fcommons.wikimedia.org\u002F?curid=44575517\" rel=\"noopener\">Wikimedia Commons\u003C\u002Fa>","Muscovite, cleavelandite 7100.FS2014.jpg",1973,1541,[],[227,228,229,230,231],"Cleavelandit","Cleavelandita","Clevelandit","Clevelandita","Clevelandite",[],{"history":234,"applications":238},{"markdown":235,"model_version":236,"prompt_version":237,"reviewed_at":8},"Cleavelandite is not a separate mineral species but a distinctive form of **albite**, the sodium end of the plagioclase feldspar family — a group of common rock-forming minerals built around sodium, calcium, aluminium and silica. What sets cleavelandite apart is its habit: thin, lamellar, slightly warped plates that grow stacked together, often as cream-white aggregates lining the cavities of granitic pegmatites[1]. The history below is the story of how that habit came to carry a name of its own.\n\nThe ground that supplied the first scientifically described specimens was a pegmatite outcrop in **Chesterfield, Massachusetts** — still the type locality today. The **Clark Ledge pegmatite**, on what was then the Joseph Clark farm, was discovered around **1811** by **Dr. David Hunt of Northampton, Massachusetts**[2]. The vein carried green, red and blue tourmalines along with beryl, set in white feldspar and quartz, and it became one of the first American sources of gem tourmaline[2].\n\nA few years later, the man whose name the variety would carry was finishing the book that made his reputation. **Parker Cleaveland** (1780–1858) was an American chemist and mineralogist who taught at Bowdoin College in Maine for more than fifty years[3]. In 1816 he wrote *An Elementary Treatise on Mineralogy and Geology* — the first mineralogy textbook authored by a US citizen — although it only reached readers in January 1817[4]. The book unified European schools of thought for an American readership and went through a popular second edition in 1822, work that later earned Cleaveland the nickname of \"Father of American Mineralogy\"[3].\n\nThe variety itself was first formally described in **1817** by the German mineralogist **Johann Friedrich Ludwig Hausmann**, who called it *kieselspath*[5]. Two years earlier, in 1815, the Swedish-Finnish mineralogist Hans Peter Eggertz had already noted granular and radiated forms of albite that were probably the same material[6]. Neither name took hold.\n\nThe name **cleavelandite** itself was coined in **1823** by the English crystallographer **Henry J. Brooke**, in a short paper in the *Annals of Philosophy*[7]. Brooke had been examining specimens of the *albite* and *siliceous spar* that accompanied tourmaline from Chesterfield, and concluded that the two names referred to one species[7]. Rather than choose between them, he proposed a new name: *Cleavelandite*, \"out of respect to the Professor of Natural Philosophy in Bowdoin College, United States\"[7].\n\nDefinitions of cleavelandite have tightened over the years. In **1936**, the American mineralogist **Harold Lattimore Alling** redefined it as a triclinic mineral, distinguishing it from ordinary albite and from a high-temperature form then called *analbite*[8]. In **1968** the mineralogist Fisher studied specimens from Chesterfield itself and proposed that the name be restricted to \"warped platy masses of mineral with lamellae parallel to (010)\" — that is, to the thin sheets that split along a particular internal plane of the crystal structure — and lacking other well-defined crystal faces[9]. That strict reading would exclude many specimens commonly sold as cleavelandite, including the splayed bladed aggregates grown into open cavities at the type locality. Current usage is looser, and the varietal name now covers both the warped masses and the cavity-hosted crystal sprays[9].","claude-opus-4-7","1.7.0",{"markdown":239,"model_version":236,"prompt_version":237,"reviewed_at":8},"Cleavelandite has no industrial role of its own. Albite — the parent mineral species — feeds the ceramics and glass industries as a flux, but those mills crush massive granite and pegmatite ore without separating out the lamellar variety. Anything ground for industry is sold simply as feldspar.\n\nWhere cleavelandite earns its name is in two narrower settings.\n\nThe first is the **collector specimen market**. Cream-white blades of cleavelandite arranged around a brightly coloured tourmaline, beryl or lepidolite are among the most photographed objects in mineral dealing[1]. The Pederneira mine in São José da Safira in Minas Gerais, Brazil, and the historic gem pegmatites of the **Pala district** in San Diego County, California, both produce tourmaline specimens whose matrix is dominated by cleavelandite[1]. The variety is rarely the main attraction; it is the white stage on which the colour sits.\n\nThe second is as a **field indicator for gem-bearing pegmatites**. Geologists prospecting for tourmaline, beryl and lithium minerals read the mineral assemblage of a pegmatite for clues to its inner structure. The classic suite — quartz, microcline, **cleavelandite**, lithium-rich micas such as **lepidolite**, and coloured tourmaline — points to the upper, gem-bearing zone of a fractionated body of rock, where the last and most chemically evolved fluids crystallised[1]. Pockets within that zone, called **miarolitic cavities**, are the open spaces in which gem crystals grow freely[1]. Where cleavelandite blades line the cavity walls, the pegmatite has reached the stage where tourmaline and other gem minerals are most likely to appear."]