introduction analytical techniques yococu 2012.… · holsbeek, mathieu clar, saïd rakkaa (ipnas...
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MélanieMachowski1,HelenaCalvodelCastillo1,CécileOger1,2,DavidStrivay11I.P.N.A.S.,CentreEuropéend’Archéométrie,UniversitédeLiège,Belgium.Contactingauthors:[email protected],[email protected]
2Bibliothèque,FacultédePhilosophieetLettres,UniversitédeLiège,Belgium
IntroductionThe Nizet Manuscript is a XVIIIth century book conserved at the University of Liège(Belgium).ItcontainsthegenealogyoffourfamiliescomingfromVerviers(Belgium)andisillustratedwithmanyheraldriesandsomedrawings.Themetalliccoloursusedtoimitategoldandsilverhaveinducedanimportantdegradationofthepaper,particularlyinthecaseofthesilverimitation,whichleadstothepropagationofthestainsonseveralfolios.Moreover, bothmetallic pigmentsarealsodegradedand sometimespresentacolourdifferentfromtheoriginalone.
Aimsofthisresearch1) Identificationofthepaletteusedtodotheheraldries.2) Identificationandexplanationofthemechanismsofdegradationofthepaper.
Analyticaltechniques• Macroscopicobservation,observationunderUVlight.
• StereomicroscopeOlympusSZX99.5X‐85.5X.
• UV‐visiblespectroscopy:StellarNetEPP2000C,UV‐VisHamamatsulightsource
• PIXE:IPNASCyclotron.3MeVprotonbeam,i≤0.5nA,beamΦ=0.8mm.Workingdistance13mm.Si(Li)Siriuse2Vdetector(lowenergy)suppliedwithHefluxand,UltraLEGeGU0035PCanberrawith50µmAlabsorber(highenergy)each@40otobeamdirection.
• EDXRFmapping:PortableEDXRFdevice,MoxtekMagnumX‐RaytubeAganode@35k&200µA,beamΦ=1mm.Workingdistance21mm,KetekGmbHSDDplaced@49otobeamdirection.
Firstconclusions1) Identificationofsomepigments,currentlyusedattheXVIIIthcentury1.2) TheXRFmappingshowednomigrationofionsofbothmetallicpigments.3) Regardingthemetallicdegradationphenomenon:
i. TheKupferfraβphenomenon2couldexplainthedegradationinducedbythebrasspigment(goldencolourisbasedoncopperandzinc).
ii. Thetincontentmustplayaroleinthepaperdegradationinducedbythesilvercolour. Weassumethereareinteractionsbetweenthepigment,thebinderandthepaper.
iii. Influenceoftheinkonthedegradationmustbeexplored,asitaccentuatestheformationofthestainandthediscolorationofbothmetallicpigments.
FutureworkMolecular analyses (Raman and FTIR) will be done to identify all the pigments andunderstandtheroleoftininpaperdegradationprocesses.
Whereascopperandirondegradationofpaperhavebeenthoroughlystudied,theroleoftinremainsanunexploredsubjectinthescientificliterature.
Firstresults
Acknowledgments:AymericHolsbeek,MathieuClar,SaïdRakkaa(IPNAStechnicians),ThomasDupuis,François‐PhilippeHocquetandGrégoireChêne(colleagues).References:1Artists’Pigments(3vol.),2BANIK,G.,STACHELBERGER,H.,MAIRINGER,F.,VENDL,A.,PONALHO,J.,AnalyticalInvestigationsoftheProblemof“Kupferfraβ”inIlluminatedManuscripts,inMikrochimicaActa[Wien],I(1981),p.49–55.
OrganicblackpigmentBasedonC
Lapis‐lazuli+azurite?(Na,Ca)8(AlSiO4)6(SO4,S,Cl)2+2CuCO3.Cu(OH)2
Prussianblue+smalt?(Fe4(Fe[CN]6)3)+glasscontainingcobalt
Cu
Fe Fe/Co
Zn As Co
Channels
Counts
Cl Ca K
Al
S Si
Counts
Fe Cu
Channels
Counts
Na Mg Al Si
S K Cl
Ca
Counts
Lakepigment Lakepigment
VermilionHgS
Hg
Channels
Counts
Greencopperpigment GreencopperpigmentChannels
Cu Fe
S Cl Ca
K Si
Al Counts
Al Si P
Cl S
K Ca Cu
Cu
Counts
Channels
UmberFe2O3+MnO2
Mn Fe Ca
K
Si
S Al
Mg P
Channels
Counts
Pb
Whitelead+organicblack?2PbCO3.Pb(OH)2+carbonblack
DelayedumberFe2O3+MnO2
Channels Channels
Counts Counts
Mn Fe
Ca K S Si Al
Mg
Brasspowderpigment(Cu+Zn)+yellowunderlayer
Localisationofthedegradationduetothegoldencolour
YellowunderlayerNONDEGRADEDDEGRADED
Fe
Cu Cu
Zn
Zn As
As
Channels
Counts
Ag Fe
Cu
Localisationofthedegradationduetothesilvercolour
Tinpowderpigment(Sn)
Silverpigment(Ag)
Silvercolour
Silverhighlight
degraded
Channels
Counts
Channels
Cu Zn
Pb
Sn Counts