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UrbanGeologyinChelsea:AStrollAroundSloaneSquareRuthSiddall
SituatedintheRoyalBoroughofKensingtonandChelsea,SloaneSquareSW1,andseveraloftheneighbouringstreetsarenamedafterSirHansSloane(1660-1753)wholivedintheareainthemid18thCentury.TheareaisnowownedbytheCadoganEstateLtd.TheCadoganfamilyinheritedthisfromSloaneviahisdaughter,Elizabethanditisstillthehandsofthe8thEarlCadogan.TheeldestsonsofthisfamilyinheritthetitleViscountChelseaandthisareaisoneofthetoppiecesofrealestateinthecountry,earningthefamilyover£5billionperyear.Itiscorrespondinglyapleasantareatostrollaround,thehometodesignershops,theSaatchiGalleryaswellasatheatreandconcertvenue.Developmenttookplacebetweenthemid19thCenturyandthepresentdayanddisplaysarangeofstonesfairlytypicalofLondonBuildingduringthisperiod–alongwithafewsurprises.
Fountain,SloaneSquare,withPeterJonesDepartmentStorebehind.ThiswalkstartsatSloaneSquareUndergroundStationonHolbeinPlace,andtakesintheSquareitself,thesouthernendofSloaneStreet,DukeofYorkSquareandtheeasternendoftheKing’sRoad.ItiseasytoreturntoSloaneSquarestationwhenfinished,oryoucouldvisittheSaatchiGallerywhichdisplaysacollectionofcontemporaryarttosuitalltastes(andnone).Forthebuildingsdescribedbelow,architecturalinformationbelowisderivedfromPevsner’sguidetoNorthWestLondon(Cherry&Pevsner,1991),unlessotherwisecited.HolbeinPlaceHolbeinPlacehasbeenrecentlyredesignedasasharedspacefortrafficandpedestriansandconsequentlypavedingrey,bandedgneisssetts.Indeedthegneissisalmostamylonite1withafinegrainsizeandfinebandingofdarkhornblende-richlayersandwhitefeldspar-richlayers.Somebandsthickeninto‘augen’;awordfromtheGermanmeaningeye,andthesebulgesinthewhitebandsareeye-shaped.Thereforewe
1Astronglyshearedanddeformedmetamorphicrock.
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maycallthisrockanaugengneiss.ThepavingwaslaidmyCEDNaturalStoneandIamgratefulfortheirCEOMichaelHeapforconfirmingtheprovenanceofthisstonetobetheSouthernSwissAlps,locatedjusttothenorthofLugano.ThestoneisavarietyofMaggiaGneissfromtheLepontineAlps,exposedinatectonicwindow,TheLepontineDomeandprobablyquarriedfromtheRiveoValley.Thisregionexposesaseriesofnappes,metamorphosedathighAmphiboliteFacies,representingacorecomplexofoncedeeplyburiedrocks.Theywereexposedafter18MaduringmovementontheRhone-SimplonDetachment.TheMaggiaNappeisexposedintheMaggia&SimanoKlippen.ItiscomposedofLateCarboniferous,tonaliticgneisses,whichunderwentafinal,peakmetamorphiceventintheTertiary(seeStecketal.,2013).Theserocksaredeformedintofold-nappesandhaveastrong,structuralfabric.ThisisclearinthegneisssettshereatHolbeinPlace.Afewexamplesshowhairpin-shaped‘isoclinal’foldsinthefinelaminations.
ThekerbstonesareinSilverGreyGranite,atwo-micagraniteofCretaceousagefromFujianinsouth-eastChina.RoyalCourtTheatreTheRoyalCourttheatrewasbuiltin1888andisafocalpointforSloaneSquare.Thereislittleofgeologicalinterestintheexterior,buttheinteriorhasrecentlybeenre-modelledbyarchitectsHowardTompkins.Ifitisopen,theinteriorisworthapeak.TheauditoriumhasamuralbyartistAntoniMalinowski,completedin2000andpaintedinvermillion,themercurysulphidepigmentknowntogeologistsasthemineralcinnabar.Thisisprobablyoneofthelargestartworksconstructedofthisspectacularpigment,onlyrivalledbythemuralsintheVillaoftheMysteriesinPompeii.Malinowskihasagreatinterestinthematerialsusedbyartistsincludingtraditionalartistspigments,manyofwhichwerederivedfromminerals.CinnabarwasfoundandminedforpigmentsinAlmadeninsouthernSpainandatMonteAmiatainItalyover2000yearsago.InthefareastcinnabarwasfoundinassociationwiththermalspringdepositsinChinaandthatisthemainsourceofpigment-grademineralcinnabartoday.CourtLodge,48SloaneSquareNextdoortotheRoyalCourtTheatreisCourtLodge,housingToni&Guy’shairdressersat48,SloaneSquare.Thegroundflooriscladwithpolished,rusticatedigneousrocks,typicalofthearchitectureofthelate19thCentury.Threestonesareusedhere.FirstlythearchandpilastersaroundthedoorwayandthearchesenclosingthewindowsareofsalmonpinkPeterheadGranite.ThisstonewasincrediblypopularinVictorianarchitectureandcanbeseenonmanybuildings–particularlypubs–throughouttheBritishIsles.ItcomesfromStirlinghill,northofAberdeenandwasbroughtsouthwhentherailwaysopenedfromAberdeentoLondoninthe1880s.GeologicallythePeterheadGraniteisa400millionyearoldplutonoftheCairngormSuite,apost-tectonicCaledoniangranite.Itcontainsdistinctivepinkfeldsparandsmoky,dark
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greyquartz.TheothertwostonesarebothvarietiesofNorwegianlarvikiteandmarketedasMarinaPearl(grey)andEmeraldPearl(dark,bronzygreen).ThesearebothfromLarvikinthesouthernpartoftheOsloGrabenandaremonzonitesassociatedwiththeformationofthePermianriftvalley.Theywereintrudedintoacentredcomplexat290Ma.Themostdistinctivefeatureoflarvikitesarethe‘schillerescent’feldsparcrystalswhichflashpeacockblue.Thisiscausedduetorefractionoflightbetweenthinlayersinthecrystallographicstructure.Forthoseinterestedinfeldspars,technicallytheyareoligoclaseperthites.Larvikiteswereverypopulardecorativestonesfromthe1880sonwardsandwereshippedtoAberdeentothenbetransportedsouthbytrain.TheyarestillquarriedtodayandareNorway’snationalstone.
TurnrightintothestreetrunningNWwhichleadstoClivedenPlace,butisstillpartofSloaneSquare.BlandelBridgeHouseOnyourrightyouwillseethebeautifullycarvedstoneplaquedemarkingBlandelBridgeHouseat56,SloaneSquare.TheRiverWestbourneoncecrossedtheroadhereandwasspannedbytheeponymousBlandelBridge(theriverpassesovertheplatformatSloaneSquaretubestationinasquare-sectionpipe).Theplaqueiscarvedfromapieceoffinelylaminated,redsandstone,withfinebeddinglaminations.Althoughcomposedprimarilyofquartz,theredcolourisimpartedbytheironoxidemineralhematite(Fe2O3).TheoriginofthisstoneisunknownbutitisprobablyaTriassicsandstonefromNorthernEnglandorSWScotland,perhapsfromStBees,CarlisleorDumfries&Galloway.
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ReturntoSloaneSquareproperandcrosstheroadontotheSquareitself.ChelseaWarMemorialTheWarMemorialstandsattheeasternendofSloaneSquareandcommemoratesthemenandwomenofChelseawhodiedintheFirstandSecondWorldWars.Thestyleofthememorialisa‘crossofsacrifice’,amuchrepeatedformdesignedtobereproducedinarangeofsizesbySirReginaldBlomfieldin1918.Characteristicallyabronzelongswordisattachedtooneside.ThisstyleofmemorialisfoundinmostlargewarcemeteriesandisusedfortownmemorialsintheUK,CommonwealthandtheUnitedStates.Likemanyofitsbrethren,thiscrossanditsplinthisconstructedfromPortlandWhitbed.PortlandstonehastraditionallybeenusedforCommonwealthwargravesanditisusedonmanywarmemorialsinLondonandbeyond(seeSiddall,2014).WhitbedisoneofthethreemainvarietiesofthePortlandLimestonebuildingstonesandthecommonestseeninarchitecture.Itisawhiteooliticlimestonewithscatteredshellfossils,mainlytheoysterspeciesLiostreaandspinyoysters.Bothtypescanbeseenhere,alongwithmanybrokenshellfragments,weatheringproudoftheooliticmatrix.Portlandstonewasdepositedinshallow,tropicalJurassicseasataround145millionyearsago.SloaneSquarePavingThesquareispavedwithYorkStone.ThistermisusedgenericallytodescribeflagstonesfromthePenninesofLancashireandWestYorkshire(andfromnowherenearYork).Therearenumerousquarriesinthisregionwhichhavebeeninoperationforseveralhundredyears–40wereinoperationin1900.Manyareclosedbuttherearearound20large,workingquarrieswhichstillproduceYorkStonevarietiestothisday(Lott,2012).TheflagslargelycomefromthePennineLowerCoalMeasuresGroupofUpperCarboniferousage,wheretheyareinterbeddedwithcoalseamsandshales.Theyaregenerallyfluvialsandstones,laiddowninbraidedriversystemsandarecomposedofquartz,withvariableamountsofmicaandorganicmatter.Liesegangbandingisacommonfeatureofthesestonesandisapostdepositionalfeature.Thesearetheconcentricbandsofironwhichstainthesurfacesofmanyoftheflagsandaretheresultofcomplexchemicalreactionsduringtheburialoftheserocks.Ofnoteherearethereservationofsedimentarystructuresonsomeoftheslabs;ripplesandloadcasts(below)arecommonandwell-preservedonthesehand-rivensurfaces,madebysplittingtheflagsalongbeddingplanesusingahammerandchisel.
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SloaneSquareFountainApleasantfountain,withalarge,octagonalbasinstandsatthesouthwestendofSloaneSquare.Thewaterflowsfromabronzenymphonapedestalinthecentreofthebasin.ItwasdesignedbyGilbertLedwardandinstalledin1953.ThebasinismadeoutofPortlandWhitbed.Exceptionallywell-preservedoysterfossilsweatherproudofthestonework,andthereisagoodexampleofanalmostperfectvalveonthesouthsideofthefountain.ThebronzeinthecentrestandsonaplinthofCornishgraniteorthe‘small-megacrystic’variety.Thishastabular,sub-alignedfeldsparsphenocrysts,around2cmlong,setinabrown,quartz-richmatrix.ThisdecorativestoneisprobablyPenrynGranite,quarriedfromtheCarnmenellisPluton,althoughitmayequallyhavebeenderivedfromtheBodminPluton.TheCornishgranitesformpartofthelargeCornubianBatholith,intrudedattheendoftheVariscanOrogenyataround290Ma.DrinkingFountainAsmalldrinkingfountain,forhumansanddogs,standsatthenorthwestcornerofthesquare.ItwasinstalledbytheMetropolitanDrinkingFountainandCattleTroughAssociationin1882,endowedbyananonymouswidowinmemoryofherhusband.IncontrasttotheCornishgraniteusedinthefountainpedestaldescribedabove,thepedestalandbasinofthisfountainarecarvedfrom‘Large-megacrystic’CornishGranitewithfeldsparphenocrystsupto10cminlength.ThesestoneswerequarriedfromtheLand’sEndPlutonatLamornaCoveandalsofromtheStAustellPlutoninthevicinityofLuxullyan.Theexactprovenanceofthisstonecannotbeobtainedfromobservationalone(below,left).Theurnatthetopofthefountainismadefromadifferentgranite,lackingthelargemegacrystsandcontainingslightlypinkishpotassicfeldsparandclotsofblackminerals.ThisisprobablyCraignairGranitefromthe391MaCriffel-DalbeattiePlutonlocatedinDumfrieshireintheSouthernUplandsofScotland,(below,right).ThisstonewascommonlyusedbytheMetropolitanDrinkingFountainandCattleTroughAssociation,afoundationformedin1859toprovidefreshdrinkingwatertothepeopleandanimalsofLondon.ItisunknownbutanunlikelyfactthatcowseverdrankthewatersofSloaneSquare.
CrossovertheroadonthenorthsideofthesquaretothebuildingonthenortheastcornerofSloaneStreet.Rag&Bone,13-14SloaneSquareThisimposingbuildingonthecornerofSloaneSquareandSloaneStreetwaspossiblyformerlyabank.ItisdesignedinanItalianatestyleandconstructedfromPortlandWhitbedwithrelativelysparsefossils.However,prominentcross-beddingisobservedonmanysurfacesshowingthisstonetohaveformedinshallow,tidallydominatedwaterswhereshoalsanddunesofoolitesandswereforminginthelateJurassicseas.WalkalongSloaneStreettoHolyTrinityChurch,nextdoor.
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HolyTrinityChurchHolyTrinityChurch,constructedin1889anddesignedbyarchitectJ.D.SeddingisthetypeofbuildingthatEricRobinsonalwaysreferredtoas‘bloodandbandages’,i.e.oneconstructedoflayersofredbrickwithinterveningwhitestonedressings.NormallyPortlandStoneisusedforthe‘bandages’,butinthiscaseitisBathStone.Closeinspectionshowsittobeacoarse-grained,cross-bedded,ooliticlimestone,alsorichinfinely-comminutedshellfragments.OverallithasapaleyellowcolourwhichimmediatelydistinguishesBathStonefromPortlandStone.
TurnrightontoSloaneTerrace.CadoganHallCadoganHallisanimpressivebuildingbuiltinaByzantine,Italianstyle.ThearchitectwasR.F.Chisholmanditwascompletedin1909.ThebuildingisnowthehomeoftheRoyalPhilharmonicOrchestra,butitwasoriginallybuiltastheFirstChurchofChrist,ScientistinLondon.TheChristianScientistswereasectfoundedinBoston,Massachusettsin1879byMaryBakerEddy.The(alleged)sciencebitwasthefactthatoneoftheprincipleaimsoftheChurchwasto"reinstateprimitiveChristianityanditslostelementofhealing".TheChurchwasextremelypopular,especiallyamongstwomen,intheearly20thCenturyandmanychurcheswerebuiltintheUSAandEurope.TheFirstChurchinLondonwas,asthenamesuggests,thefirstChristianSciencechurchinthecapital,andwasbuiltespeciallyforthedenomination.TocommemoratetheNewEnglandoriginsoftheChurch,thefoundationstonewasbroughtfromConcordNewHampshire.Inarareinstanceoftheoriginofthebuildingstonebeingrecordedonabuilding,thisfactisinscribedonthefoundationstone,whichwaslaidin1904.ThisissituatedatthewestendoftheSloaneTerracefaçade.ThemainbuildingstoneusedisPortlandWhitbed,butgraniteisusedforthefoundationstoneandthecolonnadesalongthegroundfloor.
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NewHampshire’sepithetisthe‘GraniteState’andthetownofConcordisthemainproducerofthisstone,workingtheDevonian(365Ma)ConcordPluton,oneoftheNewHampshirePlutonicSuite(Harrisonetal.,1987),posttectonicgranitesassociatedwiththeAcadianOrogeny,responsiblefortheconstructionoftheAppalachianRanges.ConcordGranitehasbeenquarriedbythefamilyfirmofSwenson’ssincetheearly20thCentury.Itisapalebuff-coloured,medium-grained,two-micagranitewithahomogeneous,undeformedtexture(below,left).Thegraniteusedforthecolonnadeandsillsishoweveradifferentstone.Ithasyellow-green,slightlykaolinisedfeldspars,milkywhitequartzandclotsofmaficminerals,biotiteandhornblende.ItisslightlycoarsergrainedthantheConcordGranite.Ihavenotbeenabletodiscovertheoriginofthisstone,howeveritstronglyresemblesMontorfanoGranitefromLagoMaggioreintheItalianLakeDistrict.ALowerPermian,pre-Alpinegranite,thisstonealongwithitsmorefamousneighbour,theBavenoGranite,hasbeenquarriedfromthe15thCenturytothepresentday(Cavallo&Dino,2015)andwaswidelyexportedinthe19thand20thCenturies.Thisstonehasafewspectacularxenolithsofagreenschistfaciescountryrockwithcoronaeofbiotite.(below,right).
ReturntoSloaneStreet.JoMalone&AnyaHindmarchStores,150&157SloaneStreet
Twostores,JoMaloneofthecornerofSloaneTerraceandAnyaHindmarchonthecornerofWilbrahamPlaceareclearlypartofthesamearchitecturalscheme;Victorianshopswithlargewindowswithinterveninggranitepilasters.ThesoclestothepillarsforbothbuildingsareofEmeraldPearllarvikite.Thepillarsthemselvesareofredgranites.ThesearetypicalofanumberofgranitesquarriedfromtheKalmarCoastofeasternSwedenandconsequentlyknownastheCoastalReds.Themaingraniteusedisabrightredgranitewithwhitetogreyquartz,redfeldsparandbiotite.ThisisthevarietyknownasSwedishBalmoral,partofthe1.8-1.6GaSmålandSuite.Asecond,slightlydarkerredgraniteisalsousedonthesebuildingswithdistinctlyopalescent,blue-violetquartz.ThisispossiblyGraversforsGranite(left),alsooneoftheSmålandSuiteextractedfromnearthetownofNorrköping.
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Chloë,153SloaneStreet153,Sloanestreet,currentlyoccupiedbyChloë,isoppositetheAnyaHindmarchstoreonWilbrahamPlace.Thegroundflooriscladindelicatelycarvedredsandstone,verysimilartothatseenatBlandelBridgeHouse.Onceagaintheprovenanceisunknown,butasabove,itisprobablyaBritishTriassicsandstone.
131,SloaneStreetAspectacularcombinationofstonesareusedonthenewbuildingat131SloaneSquare.ThebuildingisdesignedbyarchitectsStiff+Trevillion,andthestonesusedarestatedinthebuilding’sbrochure.Themainstoneusedisanorange-redsandstone.ThisisPermianLocharbriggsSandstonefromtheNewRedSandstonedepositsofDumfries&Galloway.Thestonehasbeenworkedsince1759andthequarryiscurrentlyworkedbyStancliffeStone.
LocharbriggsSandstoneandEtnaLavaStonecladdingonthefaçadeof131,SloaneStreet.ThegreystoneisfarmoreexoticandnotfrequentlyusedinLondon’sbuildings.ItisabasaltfromMountEtnaonSicily,andmarketedasEtnaLavaStone.ThebasaltflowsofEtnahavebeenexploitedforbuildingstonesinceantiquityandcomprisevesicularandnon-vesicularolivinebasalts.Anon-vesicularvarietyis
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usedhere,flowbandingisvisibleintheslabsfromstreetlevel.Accordingtothedevelopment’sbrochure,thisstoneisalsousedforinteriorflooring.Etnabecameactivearound500,000yearsagoandhaseruptedonaveryregularbasissubsequently,producingregularnewsuppliesofbuildingstone(seePunturoetal.,2006).Thevarietyusedhereisstrikingporphyriticcontainingphenocrystsof~7mmlengthofeuhedralclinopyroxeneandanhedraltosubhedralyellow-greenolivines.Accordingtotheliterature,hornblende-phyricbasaltsareuncommonofEtna,howeversomeoftheexamplesobservedhereappeartoshowthe60°cleavageintersectiondiagnosticofthisgroupofminerals.
EtnaBasalt,fieldofviewis~6cm.Euhedral,blackpyroxenecrystalsandolivegreenolivines,ReturntoSloaneSquareandturnright.J.Crew,16SloaneSquareThisredandyellowbrickbuildinghasfoundationsofablack,igneousrock.Thisisamedium-grainedgabbro,composedofgreyplagioclasefeldsparandblackpyroxeneandmagnetite.Fromadistance,thisappearstobeahomogeneousblackstone,butcloseinspectionmakesthe‘saltandpepper’effectofthefeldsparsandmaficmineralsclear.ThisisprobablyoneofthegabbrosfromtheBushveldComplex,alayered,basicintrusioninsouthAfrica,andmaybethevarietyNeroImpala.Ifso,thismakesthisrocktheoldestusedinSloaneSquarearea,at2billionyearsold.PeterJonesDepartmentStoreApieceofclassic,artdecoretailarchitecture,PeterJoneswasdesignedbyJ.A.Slater&A.H.Mobberleyin1937.ThefrontelevationofPeterJonesismainlysteelandglassandatfirstsite,seemsofnogeologicalinterest.ButwalkaroundtotherearentranceonCadoganGardens.Thispartofthestorewasextendedinthe1960s,andthestoneworkhereprobablydatesfromthattime.Themainstoneusedhereiswhite-creamTivoliTravertinefromnearRomeinItaly.Thisisayoungrockdepositedbetween115-30thousand
yearsagoinathermalspringenvironment.Totherightoftheentrancewithitsmosaicontheporchfloor,theshopwindowhasalonepillarcladinagreymetamorphicrock,OttaSchistfromNorway.ThisstoneisalsousedaspanelscladdingtheKing’sRoadfaçadeofthestoretoo.Theschisthasasheencausedfromsheetsofalignedmuscoviteandlargefansand‘bowtie’texturesformedofneedle-shapedcrystalsofactinolite(left).OttaSchistisametasediment,formedduringtheCaledonianOrogenyaround400millionyearsago.ThisisaverycommonlyusedbuildingstoneinNorway,butwaspopularintheUKinthe1960sand70s.It
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hassubsequentlydeclinedinuseherebutexampleslikethisoccasionallycropout.ReturntoSloaneSquare,crossingovertheKing’sRoadtothesouthsideofthesquare.HugoBoss,38SloaneSquareThelargeandimposingblockthatisnowoccupiedbytheHugoBossstoreisaclassicLondonPortlandWhitbedbuilding.Somegoodexamplesofoysterfossilswiththicklaminatedshellsarepresent.Oysterssecretecalciteunlikemanyothermolluscswhichsecretearagonite.Unlikearagonite,calciteisgeologicallystableandthereforetheseshellsdonotrecrystalliseduringtheprocessoffossilisation,leadingtoexceptionalpreservationoftheshellstructure.BarclaysBank,29-30SloaneSquareWalkingbacktowardstheKing’sRoad,weencounterBarclay’sBankwithitsplateglasswindowsurroundedbyajadegreen,brecciatedserpentinite,whichalsoextendstosurroundthedoorwayof29SloaneSquare.Themainsupplyofserpentinite‘marbles’alsoknowninthebuildingtradeas‘ophicalcites’istheFrenchandItalianAlps,withthemainquarryingareacenteredaroundtheVald’Aosta.Herevariousstonesknowngenericallyas‘VerdiAlpi’arequarriedfromtheLateCretaceousophiolitesoftheCombinandZermatt-SaasAlps.Theyarecomposedofserpentine-groupminerals,tremolite,actinoliteandcalciteveins.Fromthecolourofthisrock,theserpentinemineralisprobablythejade-colouredantigorite(below).
TurnleftintotheentrancepassagetoDukeofYorkSquare.DukeofYorkSquareDukeofYorkSquareisa‘retailcourt’andopenpublicspacedesignedbyPaulDavis&PartnerswithlandscapearchitecturebyElizabethBanksAssociatesworkingwithstonecontractorsStonewest(CABE,2011).ThepassageentrancetoDukeofYorkSquarefromSloaneSquareiscutintoaVictorianfaçadewithsquaresection,engagedpilastersofPeterheadGranite.TheSquarewasdevelopedintheyear2000andthecolumnsandfaçadeareofyellowisharchitecturalceramic.HoweverthetwocolumnsattheentrancesitofpedestalswhicharecubesofBalmoralGranite.Thisisastonewhichcomesinafineandcoarse-grainedvariety,ofwhichthisisthecoarse.BalmoralGraniteisquarriedfromtheVehmaaBatholithinSWFinland,notfarfromthetownofTurku(seeSelonenetal.,2011).Thisisanancientrock,almost1.6billionyearsold.Itisavarietyofrapakivigranitecalledapyterliteandcomposedofredpotassicfeldspar,quartz,plagioclase,biotiteandhornblende.Walkingintotothepassage,portionsofthewallsarecladwithapolishedpalegreygranitewhichextendsintotheopenairofthesquareonthefoundationsofthebuildingswhereithasapredominantlyaxed-
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dressedfinish.UnfortunatelyIdonotknowtheprovenanceofthisstone.Ithasaslightlyporphyritictexturewithphenocrystsofslightyellowishpotassicfeldsparinamedium-grainedmatrixofwhitefeldspar,translucentgreyquartzandblackbiotite.Thefirstbuildingsweencounterinthesquarearebuiltfromyellowbrickonfoundationsofgreygranite.Thesecondblock,however,iscladonthegroundfloorinawhite,coarselyooliticlimestonewithabundantshellfragments.ThisisaPortugueselimestonecalledMocaCrème.ItcomesfromtheLusitanianBasin,amiddleJurassicLimestoneoftheValverdeFormation.ThepavinginthesquareisMoorfieldHardYorkStone,afine-mediumgrainedsandstonewithstrong,darkrustcoloured,liesegangbanding.Thecolouroftheflagsvariesfrombufftogrey,showingoxidisedandreducedareas.This‘YorkStone’varietycomesfromtheMillstoneGritGroupratherthanthePennineCoalMeasures.ItisquarriedatCroslandHillinHuddersfieldfromtheRoughRockoftheRossendaleFormation.ThesestrataunderlytheCoalMeasuresandlikethemareUpperCarboniferousfluvialsandstones.ThestonewassuppliedbyJohnsonWellfieldQuarries.ThesquareopensupatthewesternendintoapavedspacealongsidetheSaatchiGallery(formerlytheRoyalMilitaryAsylum).TheMoorfieldHardYorkStonecontinueshereasthemainpavingmaterial,butitiscounteredwithstreetfurnitureandpavedstripsofgrey,finegrainedPietraSerena.ThisisastonefromnearFlorenceinTuscany,Italy.ItisanOligocene-EarlyMioceneturbiditicsandstone,partoftheAlpineTuscanNappe.ThiswasoneofthegreatbuildingmaterialsofRenaissanceItaly,withmanymonumentalbuildingsconstructedofthisstone,especiallyinFlorence.
MoorfieldHardYorkStoneandPietraSerenainDukeofYorkSquare.StatueofSirHansSloaneAstatueofSirHansSloanestandsattheeastendofthesquare.Sloane,physician,naturalistandcollectorwasborninIrelandin1660.HetravelledtoLondonandthenFrancetostudymedicine.AfterasojourninJamaica,wherehemetandmarriedhiswife,ElizabethLangleyRose,heeventuallysettledinChelseawherehewasinstrumentalinthedevelopmentoftheChelseaPhysickGardenandhisCabinetofCuriosities
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becamethefoundingcollectionoftheBritishMuseum.HediedinChelseain1753andisburiedatChelseaOldChurch.Oneofhisdaughters,alsonamedElizabeth,marriedCharlesCadogan,whoinheritedSloane’slandinChelseaandtheCadoganfamilyremainthelandownersheretothisday.ThestatuestandinginDukeofYorkSquarecouldeasilybemistakenasonecontemporarywithHansSloane’slife.Howeveritwasinfacterectedin2007bysculptorSimonSmith.ItismadefromPortlandWhitbedandhasthecharacteristicslightyellowcolourtypicalofrelativelyfreshPortlandLimestone.ThisisfairlytypicalWhitbed,anooliticlimestonewithscatteredfossils.Theseincludebrokenshellfragmentsandalsosogoodexamplesofsectionsthrougharticulatedoystershells.Somegoodexamplescanbeseenonthecovingoftheplinth,belowtheartist’ssignatureatthebackofthestatue.TheKing’sRoadwasoriginallyconstructedinthe17thCenturyasadrivewaytoHamptonCourtPalace.Assuchitranthroughthecountrysideandmarketgardensbeforebecomingdevelopedintotheretailandresidentialareaweknowtodayinthemid19thCentury.Crossovertheroadtotheimposingshopfrontatnumber72,King’sRoad.72,King’sRoadThisimpressivebuilding,currentlyoccupiedbytheclothingandaccessoriescompany‘&OtherStories’,wasformerlytheColvilleTavern,apublichouse,constructedin1844.Thegeologicalinterestliesinthepillarsbetweentheshopwindows.Thesearemadefromredgranitewithgreygranitepedestalsandfoundations.OriginalstoneworkisinsituontheBlacklandsTerracefaçade.HerewehaveaclassicpairingofpinkPeterheadGraniteandgreyCairngallGranite.Thelatterstoneisfromanintrusioncross-cutbythePeterheadPluton,theForestofDeerGranite,a470Masyn-tectonicCaledonianGranite.Itisagrey,unfoliatedgranitewithblotchy-appearingwhitefeldsparphenocrysts.CairngallwasquarriedatFlushing,Aberdeenshire.BothPeterheadandCairngallarenolongerquarried.IndeedtheCairngallQuarryatFlushingisnowariflerange.ClearlysimilarstonesweresourcedtoreplacethegranitesusedontheKing’sRoadfaçade.HerethepinkgraniteisthefinegrainedvarietyofFinnishBalmoralGranitestandingonafoundationsofagreygraniteofunknownprovenance.
References
131SloaneStreetbrochure:http://www.131sloanestreet.co.uk/downloads/SloaneSt_OfficeBrochure.pdf
Bourke,J.,2014,CadoganfamilyseetheirLondonpropertyportfoliorisetorecord£5.2bn.,TheIndependent;Thursday11June2015:http://ind.pn/1GCgqXy
CABE,2011,CommisionforArchitectureandtheBuiltEnvironment:DukeofYorkSquare;http://webarchive.nationalarchives.gov.uk/20110118095356/http:/www.cabe.org.uk/case-studies/duke-of-york-square/description
CadoganEstatesLtd.:http://www.cadogan.co.uk
Cavallo,A.&Dino,G.A.,2015,GranitesoftheVerbano-Cusio-OssolaDistrict(Piedmont,NorthernItaly):PossibleCandidatesfortheDesignationof“GlobalHeritageStoneProvince”andaProposalofaGeotouristicRoute.,In:Lollino,G.etal.,(Eds).,EngineeringGeologyforSocietyandTerritory–Volume5:UrbanGeology,SustainablePlanningandLandscapeExploitation.,267-271.
CEDNaturalStone:http://www.ced.ltd.uk/commercial-projects/quartzite-gneiss/holbein-place
Cherry,B.&Pevsner,N.,1991,PevsnerArchitecturalGuides;TheBuildingsofEngland:London3:NorthWest.,YaleUniversityPress,Newhaven&London.,808pp.
ChurchofChrist,Scientist:https://en.wikipedia.org/wiki/Church_of_Christ,_Scientist
Harrison,T.M.,Aleinikoff,J.N.,andCompston,William,1987,ObservationsandcontrolsontheoccurenceofinheritedzirconinConcord-typegranitoids,NewHampshire:GeochimicaetCosmochimicaActa,v.51,p.2549-2558.
JohnsonWellfieldQuarries:http://www.myersgroup.co.uk/jwqc/stones.asp?catID=83
LondonRemembers:ChelseaWarMonument:http://www.londonremembers.com/memorials/chelsea-war-monument
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Lott,G.,2012,Strategicstonestudy:abuildingstoneatlasofWest&SouthYorkhire.,EnglishHeritage.,25pp.http://www.bgs.ac.uk/mineralsuk/buildingStones/StrategicStoneStudy/EH_atlases.html
Punturo,R.,Russo,L.G.,LoGiudice,A.,Mazzoleni,P.&Pezzino,A.,2006,BuildingstoneemployedinthehistoricalmonumentsofEasternSicily(Italy).Anexample:theancientcitycentreofCatania.,EnvironmentalGeology,50,156-169.
Selonen,O.,Ehlers,K.,Luodes,H.&Karell,F.,2011,MagmaticconstraintsonlocalizationofnaturalstonedepositsintheVehmaarapakivigranitebatholith,southwesternFinland.,BulletinoftheGeologicalSocietyofFinland,Vol.83,25–39.
Siddall,R,2014,TheStonesofLondon’sWarMemorials;UrbanGeologyinLondonNo.23;http://www.ucl.ac.uk/~ucfbrxs/Homepage/walks/WarMemorials.pdf
SimonSmith:http://www.simonsmith.plus.com/figurative.html
Steck,A.,DellaTorre,F.,Keller,F.,Pfeiffer,H-R.,Hunziker,J.&Masson,H.,2013,TectonicsoftheLepontineAlps:ductilethrustingandfoldinginthedeepesttectoniclevelsoftheCentralAlps.,SwissJournalofGeosciences,106,427-450.
Stonewest:DukeofYorkSquarecasestudy:http://www.stonewest.co.uk/sectors/public/duke-of-york-–-hard-landscaping.aspx
IndexofStonesBalmoralGranite–DukeofYorkSquare(SloaneSquareentrance);72,King’sRoad.BathStone–HolyTrinityChurchCairngallGranite–72,King’sRoad.ConcordGranite–CadoganHallCraignairGranite–SloaneSquareDrinkingFountain.
EmeraldPearlLarvikite–CourtLodge,150SloaneStreet(JoMalone);157SloaneStreet(AnyaHindmarch).EtnaLavaStone–131,SloaneStreet.GraversforsGranite–150SloaneStreet(JoMalone);157SloaneStreet(AnyaHindmarch).GreyGranite–DukeofYorkSquare.LargeMegacrysticCornishGranite–SloaneSquareDrinkingFountain.LocharbriggsSandstone–131,SloaneStreet.MaggiaGneiss–HolbeinPlace.MarinaPearlLarvikite–CourtLodge.MocaCrème–DukeofYorkSquare.MontorfanoGranite–CadoganHallMoorfieldHardYorkStone–DukeofYorkSquare.NeroImpala–16,SloaneSquareOttaSchist–PeterJonesDepartmentStore.PenrynGranite–SloaneSquareFountain.PeterheadGranite–CourtLodge;72,King’sRoad.PietraSerena–DukeofYorkSquare.PortlandWhitbed–ChelseaWarMemorial;SloaneSquareFountain;13-14SloaneSquare;CadoganHall;38,SloaneSquare;StatueofSirHansSloane.RedSandstone–BlandelBridgeHouse,153,SloaneStreet(Chloë).SilverGreyGranite–HolbeinPlace.SwedishBalmoral–150SloaneStreet(JoMalone);157SloaneStreet(AnyaHindmarch).TivoliTravertine–PeterJonesDepartmentStore.VerdiAlpi–29-30,SloaneSquare.YorkStone–SloaneSquare.
Howtocitethisarticle:
Siddall,R,2016,UrbanGeologyinChelsea:AStrollAroundSloaneSquare.,UrbanGeologyinLondonNo.33,http://www.ucl.ac.uk/~ucfbrxs/Homepage/walks/SloaneSquare.pdf
LocationsofthebuildingsdescribedaboveandbriefdetailsofthestonesusedcanalsobefoundintheLondonPavementGeologyarchive:http://londonpavementgeology.co.uk
©DrRuthSiddall,UniversityCollegeLondon,GowerStreet,LondonWC1E6BT,UK:[email protected]://www.ucl.ac.uk/~ucfbrxs/Homepage/UrbanGeology.htm;Facebook|Cultural&UrbanGeology|Twitter:@R_Siddall|#UrbanGeology