MélanieMachowski1,HelenaCalvodelCastillo1,CécileOger1,2,DavidStrivay11I.P.N.A.S.,CentreEuropéend’Archéométrie,UniversitédeLiège,Belgium.Contactingauthors:mmachowski@student.ulg.ac.be,hcalvo@ulg.ac.be

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