In situ fluorimetry: a powerful non-invasive diagnostic technique for natural dyes used in artefacts Part I. Spectral characterization of orcein in solution, on silk and wool laboratory-standards and a fragment of Renaissance tapestry.
In this paper the potentialities of spectrophotometric and fluorimetric techniques for identifying the materials used in artistic textiles are investigated. A portable non-destructive instrument suitable to record fluorescence spectra on surfaces was set up and successfully experienced. A naturally occurring dye, orcein, which was widely used in antiquity for textile dyeing, has been spectrally characterized in both solution and powder. Laboratory samples of wool and silk orcein-dyed threads were analysed before and after ageing. An original fragment of Renaissance tapestry was also analysed. The textile (wool) and the colourant (orcein) were recognised by comparison with the data from the laboratory samples.
Clementi
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C
Laboratory of Photophysics and Photochemistry, Dipartimento di Chimica, Università di Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy.
Miliani
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C
Romani
A
A
Favaro
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G
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004396:Coloring Agents / Q000032:analysis / Q000737:chemistry*; D008956:Models, Chemical; D010078:Oxazines / Q000737:chemistry*; D012680:Sensitivity and Specificity; D047011:Silk; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013053:Spectrophotometry / Q000379:methods; D013784:Textiles; D014466:Ultraviolet Rays; D014935:Wool
D004396:Coloring Agents; D010078:Oxazines; D047011:Silk; C002313:PAcein