Stuck like glue: Wood tar as a medieval stone adhesive

This study outlines a medieval stone repair technique involving wood tar. In the process of condition assessment, an unusual adhesive was identified used for repairs and indents on Stavanger Cathedral, a medieval Norwegian soapstone structure. Based on appearance and context, an initial hypothesis was formulated that tar may have been used as a historic repair method. This hypothesis was subsequently tested and confirmed through analysis. Samples of the adhesive were investigated using light microscopy, scanning electron microscopy with energy-dispersive spectroscopy, Fourier-transform infrared spectroscopy and gas chromatography–mass spectrometry. The material was radiocarbon dated and the date found to coincide with the reconstruction of the choir following a fire in the latter quarter of the 13th century. Several hundred findings of tar repairs have so far been identified on the cathedral, indicating comprehensive use of tar as a medieval adhesive for soapstone. These findings have implications for the development of an alternative conservation adhesive based on traditional materials.publishedVersio

Status quo, ongoing challenges, and future perspectives - after more than 20 years of practice in rock art documentation, conservation, and management i southwestern Norway

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Transplantasjonsforsøk med irsk hinnelav (Leptogium hibernicum)

Oppdragsgiver: Rådgivende Biologer AS/Fylkesmannen i HordalandIrsk hinnelav (Leptogium hibernicum)(figur 1) er vurdert som kritisk truet (CR) i «Norsk rødliste for arter 2015» (Henriksen & Hilmo 2015), og har vært vurdert som kandidat til å få status som prioritert art etter naturmangfoldloven. I forbindelse med dette ble det utarbeidet et faggrunnlag for arten i 2013 (Bjelland & Ihlen 2013). Om arten får status som prioritert art er usikkert, i og med at en i dag ønsker å fokusere på arter som i tillegg til å være truet også er norske ansvarsarter, dvs. arter med forekomst i Norge med mer enn 25 prosent av europeisk bestand. I 2018 er det utarbeidet kunnskapsgrunnlag og vurdering av tiltak for 90 kritisk og sterkt trua ansvarsarter i Norge (Kyrkjeeide m.fl. 2018), men irsk hinnelav er ikke blant disse. I dag er Irsk hinnelav kun kjent fra syv lokaliteter; i Rogaland (Gjesdal, Hjelmeland og Suldal kommuner) og Hordaland (Etne kommune)(figur 2). Irsk hinnelav er utelukkende registrert på styva asketrær i Norge, og ser ut til å være knyttet til rik edellauvskog, hagemark og høstingsskog. I utkast til faggrunnlag for irsk hinnelav i Norge (Bjelland & Ihlen 2013) er transplantering av diasporer nevnt som et tiltak for å øke populasjonen av arten i Norge og vil kanskje være helt avgjørende for om populasjonen overlever i Norge

The occurrence of biomineralisation products in four lichen species growing on sandstone in western Norway

High performance thin-layer chromatography/thin-layer chromatography, X-ray diffraction, and scanning electron microscopy analysis of thallus and lichen-rock interface samples, were undertaken to characterize biomineralization products in Fuscidea cyathoides, Ochrolechia tartarea, Ophioparma ventosa, and Pertusaria coralline, growing on sandstone in western Norway. Whewellite (monohydrate form of Ca oxalate) was found in the thallus of all species, but not in any of the weathering rinds beneath the species. A significantly higher amount of whewellite was detected in the thalli of F. cyathoides and O. ventosa than in the other two species. There were only a few differences in whewellite occurrence between the thallus edge and centre samples in the four species. HPTLC/TLC and SEM analysis indicate that lichen compounds occur within the rock beneath some of the lichen specimens. Only divaricatic acid was observed within the weathering rind beneath O. ventosa. No lichen substances were found in the weathering rind beneath F. cyathoides and P. corallina, whereas gyrophoric and lecanoric acids were found in the weathering rind beneath O. tartarea

Rock Art. A Guide to the Documentation, Management, Presentation and Monitoring of Norwegian Rock Art

The guide was published in 2007, and the text has not been updated since. Some parts of the guide does not comply with today's routines and procedures

Bergkunst. En veiledning i dokumentasjon, skjøtsel, tilrettelegging og overvåking av norsk bergkunst

Utarbeidet av Norsk Faggruppe for Bergkunstkonservering på oppdrag fra Riksantikvaren. NB: Veiledningen er ikke oppdatert siden 2006 og inneholder tekst som ikke følger nåværende rutiner og prosedyrer