Analysis of 16th century Qazwini manuscripts by Raman microscopy and remote laser Raman microscopy

An in situ, non-intrusive study of three very rare similar 16th century copies of the Qazwīnī manuscript Ajā'ib al-makhlūqāt wa gharā'ib al-mawjūdāt (the Wonders of Creation and Oddities of Existence) has been performed using Raman microscopy. Seven pigments were identified, of which six were present on each manuscript: vermilion (mercury(II) sulfide), red lead (dilead(II) lead(IV) oxide), lead white (basic lead(II) carbonate), lapis lazuli, carbon black and Indian yellow (magnesium salt of euxanthic acid) and one, verdigris (basic copper(II) ethanoate), on two of the manuscripts. Indian yellow and verdigris have not previously been identified in situ and non-intrusively by this technique on any historical artefact. Each manuscript has been conserved to a different degree and the illuminations on each preserved differently. The degradation of verdigris and lapis lazuli was found to be much worse on one of the manuscripts due at least partly to a particular conservation treatment. The new technique of remote laser Raman (RLR) microscopy was also used to analyse the pigments on one of the manuscripts: this is the first time that RLR microscopy has been applied to archaeometric analysis and the study shows that this technique will make possible the analysis, non-destructively and in situ, of historical artefacts of almost any size. © 1998 Academic Press.