TurkishJournalofEarthSciences (TurkishJ.EarthSci.),Vol.16, 2007,pp.109-116. Copyright©TÜB‹TAK AMineralogicalNoteonBoulangerite, GeocroniteandYeneriteFromNearIfl›kDa¤› (K›z›lcahamam-Ankara),Turkey W.E.SHARP1,MARKWIELAND1 &STEVENK.MITTWEDE1,2 1DepartmentofGeologicalSciences,UniversityofSouthCarolina,Columbia,SouthCarolina29208,USA (E-mail:[email protected]) 2 MüteferrikaConsultingandTranslationServicesLtd.,P.K.290,TR–06443Yeniflehir,Ankara,Turkey Abstract: Microprobestudieshavefacilitatedrecognitionofthefirstdocumentedoccurrenceofgeocronitefrom Ifl›kDa¤›(Ankara,Turkey).WhileyeneriteremainsadiscreditedspeciesalongthePbS-Sb 2S3 compositionaljoin, ouranalysesshowsignificantarsenicasdidtheoriginalanalysesforyenerite;thus,thisnamemightberetained forarsenic-bearingvarietiesofboulangerite. KeyWords: Pb-Sbsulphosalts,boulangerite,geocronite,yenerite,plagionite,microprobe,slag Ifl›kDa¤›(K›z›lcahamam-Ankara)Yak›n›ndaBulunan Bulanjerit,JeokronitveYenerit‹le‹lgiliBirMineralojikNot Özet: Mikroprobçal›flmalar›n›nyard›m›yla,Ifl›kDa¤›(Ankara,Türkiye)yak›n›ndabulunanjeokronitinvarl›¤›ilkkez saptanm›flt›r.Yenerit,PbS-Sb 2S3 bileflimselçizgisiüzerindeayr›birmineraltürüolarakkabuledilemezsebile, orijinalanalizleringösterdi¤igibibuçal›flmadasunulananalizlerdearsenikelementininönemlimiktardavar oldu¤unugöstermektedir.Dolay›s›ylaarsenikçezenginbulanjeritleriçinyeneritad›tavsiyeedilebilmektedir. AnahtarSözcükler:Pb-Sbsülfotuzlar›,bulanjerit,geokronit,yenerit,plajyonit,mikroprob,cüruf Introduction Theoldworkingsaresituatedjustoffofthesouth In1943,yenerite(Steiger&Bayramgil1943)was slopeofIfl›kDa¤›atthenorthernendofSal›nYaylas›, describedasanewmineralspeciesfromacomplex adjacenttoandimmediatelywestoftheroadfrom sulphidedepositnearIfl›kDa¤›,~80kmnorthofAnkara Ya¤c›hüseyinvillagethatdescendstotheuplandmeadow, innorth-centralTurkey(Figure1).However,afewyears whichisusedasasummerpasture.AnaveragedGPS- later,yeneriteandfalkmanite(Robinson1948)were acquiredlocationfortheworkings/spoilsis40°39'11.2" foundtohavethesamex-raydiffractionpatternas Nlatitude,032°47'05.7"Elongitude. boulangeriteand,consequently,thosetwospecieswere ThedepositatIfl›kDa¤›wasworkedinByzantine discredited. times,ashasbeendocumentedbyC-14datingof InMay1997andagaininMay1999,twoofthe charcoalfromwithinslagsfoundontheupland-meadow authorshadtheopportunitytovisittheminenearIfl›k flatsimmediatelybelowthedeposit.Apreviously Da¤›.Onbothoccasions,anumberoforespecimenswere publishedresult(Seeliger etal. 1985,p.601)gavean collectedfromtheoldminespoilsandtakenbacktothe ageof1160±40B.P.,oradateof880C.E.Thisdate laboratoryforcloserexamination.Theuplandmeadow, isnowsupplementedbydatesobtainedonsamples knownasSal›nYaylas›,inwhichtheoldmineislocated, collectedin1997.AC-14ageof695±65BPyearswas ispartofaprotectednaturalareaand,thus,itisunlikely obtainedonbulklumpsofcharcoalwhichwerecollected thatanyneworematerialwillbecomeavailableinsofaras fromamongpiecesofslagcomingoutofastreambank additionalexplorationanddevelopmentareforbidden. whichiserodingthroughtheslagpile(GeochronLabs, 109 IfiIKDA⁄I(KIZILCAHAMAM–ANKARA)SULPHOSALTS Gerede Çerkeþ BOLU Iþýkdaðý ÇANKIRI Þabanözü Çamlýdere Kýzýlcahamam Dam Beypazarý Çubuk ANKARA KIRIKKALE Polatlý Bala Sivrihisar Haymana Kaman KIRÞEHÝR N Hirfanlý Dam 050Kulu km Figure1. LocationmapofIfl›kDa¤›. GX-23290).Inaddition,anAMSC-14ageof910±50 BiringuccioandAgricola)oftherecoveryofwhitearsenic yearsBPwasobtainedonsmallquantitiesofcharcoal byfuming.Certainlytherecoveryofarsenicfrom whichwereextractedfromfreshlybrokenpiecesofslag arsenopyritebyfumingwouldhavebeenconfoundedby (GeochronLabs,GX-23366-AMS).Thesenewdates thepresenceoflargequantitiesofSO 2 (Azcue&Nriagu correspondto1255C.Eand1040C.E.,respectively,and 1994,p.5). whilesomewhatlater,arestillwithinByzantinetime. Laterexplorationsarereportedfromtheearly1800's OreMineralogy (Bayramgil1945,p.45)andagainin1942(Bayramgil 1945),butnoneoftheseattemptsseemtohavebeen ThegeologicalsettingandmineralogyoftheoresatIfl›k successful.Moreover,itisunclearwhythefirstattempt Da¤›duringthelastseriousexplorationofthedeposit wasabandoned.Onemightpresumethatthepurpose havebeenfullydescribedbyBayramgil(1945).His wastoextractleadandpossiblysilverfromthecomplex detailedpetrographicexaminationyieldedthefollowing ores.Perhapstheyfoundtheorestobetoopoorinlead parageneticsequence(Bayramgil1945,p.79,1946): insofarastheabundantsphalerite(false-galena)might tourmaline+cassiterite+apatite+epidote,arsenopyrite; havebeenmistakenforthelessabundanttruePb-bearing sphalerite+chalcopyrite;pyrite;galena-I;calcite; speciesofgalenaandboulangerite;alternatively, boulangerite/geocronite+para-ankerite;galena-II;and impuritiesofantimonyintheleadextractedmayhave quartz+barite. madeittoohardtobeuseful,suchasforgunshot Ourexaminationofpolishedthinsectionsand (Bayramgil1945,p.45).Furthermore,theoresarequite backscatterimagesshowsafine-grainedequigranular richinarsenopyrite.Whentheorewassmelted,abundant texture,withtheoremineralsembeddedinamatrixof arsenicfumeswouldhaveprovenquitepoisonousto fine-grainquartz.Theoreminerals–indecreasingorder anyoneintheneighbourhood;ofcourse,itispossiblethat ofabundance–arepyrite,arsenopyrite,sphalerite, theoreswereactuallyusedtorecoverarsenic,notlead. boulangeriteandgalena.Oursectionsdidnotshowany However,thereseemstobenomentioninRoman ganguemineralotherthanquartz.Thegrainsofpyrite sources(e.g.,Pliny)orinlatemedievalsources(e.g., andarsenopyriteareeuhedral,whilethoseofsphalerite, 110 W.E. SHARPET AL. a b c d Figure2. (a) Abackscatterimagefromsectionidg2showingananhedralgrainofboulangerite(boul)witheuhedralgrainsofpyrite(py)and arsenopyrite(asp),andanhedralgrainsofsphalerite(sph),allembeddedinamatrixofquartz(qtz).(b) Abackscatterimagefromsection idg1centredonagrainofboulangerite(boul)surroundedbyeuhedralgrainsofarsenopyrite(asp)andanhedralgrainsofsphalerite(sph), allembeddedinamatrixofquartz(qtz). (c) Abackscatterimagefromsectionidg2centredonananhedralgrainofgalena(gn)with geocronite(gcr),andboulangerite(boul),accompaniedbyeuhedralgrainsofpyrite(py)andarsenopyrite(asp),andanhedralg rainsof sphalerite(sph),enmeshedinamatrixofquartz(qtz). (d) Anenhancedbackscatterimageofananhedralgrainin (c) ofgalena(gn), geocronite(gcr)andboulangerite(boul).NotethedecreaseinbrightnesswithdecreasingcontentofPbasoneprogressesfrom thecore ofgalenathroughtheovergrowthofgeocronitetotheouterrimofboulangerite. 111 IfiIKDA⁄I(KIZILCAHAMAM–ANKARA)SULPHOSALTS boulangeriteandquartzareanhedral(Figure2a).The Probeanalysesofthearsenopyrite,chalcopyriteand occurrenceofchalcopyriteasfinedisseminatedgrains galena(Table1)gaveconventionalvalues.Thesphalerite withinthesphaleriteisbestobservedinreflectedlight. isnotablyrichiniron(~10%)whilethepyriteisclearly As-bearing(2–3%). MicroprobeAnalyses Inaddition,randomgrainsofleadsulphosaltshaving twodistinctlydifferentcompositionswereencounteredin Acoupleofthebetterorespecimenscollectedfromthe thecourseofmicroprobeanalyses.Thefirstofthesehas spoilheapsweresectionedwithadiamondsaw,and acompositioncorrespondingtothatofboulangerite doublypolishedthinsectionswerepreparedfor (Figure2a,b),butwiththedistinctpresenceofarsenic, microprobeanalyses.Samplesofboulangeritefromwell- whilethesecondcorrespondstothatofgeocronite.The knownlocalitieswereobtainedfromtheNational natureoftheoccurrenceofgeocronitewasnot MuseumofNaturalHistory,embeddedinepoxy,and understoodduringtheinitialanalyticalstagebecauseof polishedsectionsprepared. thehighbrightnessofalloftheleadmineralsinthe Analyseswereperformedonanelectronmicroprobe backscatterimages(Figure2c).However,uponcareful (CamecaSX-50)equippedwithfourwavelength- adjustmentofbrightness,itwaspossibletoobservethat dispersivecounters.Theaccelerationvoltagewas15kV, thegeocroniteoccursasovergrowthsongrainsofgalena withabeamcurrentof20nAandafocusedbeaminspot (Figure2d),andthatitinturnisovergrownby modeof1µm.NaturalpyritewasusedforS-Kα andFe- boulangerite. α α α K ,galenaforPb-M ,stibniteforSb-L ,arsenopyrite Thecompositionalvaluesobtainedforboulangerite α α forAs-L ,andchalcopyriteforCu-L .Peakand (Table2)canbecomparedwithmicroprobeanalysesof backgroundcountingtimesweresetfor30and15 representativematerialfromtheClevelandmine(USNM- seconds,respectively.Observedintensitieswerecorrected 97011-1and95414),Pribram,Bohemia(USNM- usingthePAPcorrectionprogram(Pouchou&Pichoir 83983)andNocheBuena,Zachetcas(USNM-115863),as 1991)suppliedwiththemicroprobe. Table1. SelectedmicroprobeanalysesofsomeoremineralsfromIfl›kDa¤›(inweightpercent). Section IDG-2 IDG-2 IDG-1 IDG-1 IDG-2 Mineral Pyrite Arseno-pyrite Sphalerite Chalcopyrite Galena Element Mn 0.04 0.00 0.41 0.00 0.00 Pb 0.00 0.00 0.00 0.00 87.10 Sb 0.00 0.00 0.01 0.00 0.10 As 2.31 44.88 0.21 0.00 0.00 Zn 0.03 0.08 56.22 0.00 0.02 Cu 0.00 0.03 0.07 34.22 0.00 S 51.19 20.27 33.48 34.83 13.32 Fe 46.01 34.15 10.67 29.08 0.31 Total 99.58 99.41 101.07 98.13 100.85 112 W.E. SHARPET AL. Table2. Analysesofboulangerite(inweightpercent). Sample 1 2 3 4 5 6 Element Pb 54.59±0.53 56.77 56.69 55.30 55.86 56.42 Sb 24.99±0.13 25.50 25.30 26.41 26.34 25.69 As 1.27±0.40 0.61 0.69 0.64 0.35 . S 18.89±0.20 18.22 18.18 18.22 18.28 18.89 Fe . 0.01 0.01 . Total 99.74 101.10 100.86 100.58 100.84 100.00 Sample 7 8 9 10 11 Element Pb 57.32 55.28 55.34 55.08 58.13 Sb 23.60 25.40 25.30 24.38 22.81 As 1.83 . S 17.06 18.19 18.08 18.65 18.43 Fe . 0.39 0.52 trace 0.57 Insol. 0.62 0.40 1.10 . Total 99.81 99.88 99.64 99.21 99.11 1.Ifl›kDa¤›,microprobe,sect.Idg-1,averageof1spoton3grains. 2.ClevelandMine,StevensCo.,Washington,USNM95414,microprobe,averageof5spots,pyriteinclusions. 3.ClevelandMine,StevensCo.,Washington,USNM97011-1,microprobe,averageof5spots,galenainclusions.