Microscopy and X-ray spectroscopy analyses for assessment of gilding and silvering techniques of Portuguese illuminated manuscripts.

The objects of this study are various local charters (cartas de foral, in Portuguese) granted by Dom Manuel I, King of Portugal (1495-1521), which substituted for medieval ones and were intended to achieve an administrative unification. These are luxuriously illuminated manuscripts, and our study aims at obtaining a better understanding of the gilding and silvering techniques applied to the parchments, in which the forais were written, between 1500 and 1520. The combined use of microscopy and X-ray spectroscopy analyses allowed us to identify the vestigial materials used for making the parchments, including products such as salt (NaCl), lime (CaO), pumice stone (SiO2+Al2O3), and chalk (CaCO3).

Spectroscopic characterization of a masterpiece: the Manueline foral charter of Sintra.

The foral charter attributed by D. Manuel I of Portugal, in 1514, to the village of Sintra was studied using Energy Dispersive X-ray Fluorescence spectrometry, Raman and Infrared micro-spectroscopies. A complete characterization of the pictorial materials used in the production of this masterpiece allowed the identification of iron gall inks used in the written text; pigments such as malachite, azurite, lead white, cinnabar, yellow ochre, gold, silver and carbon black in the illuminations and letterings; filler and binder used in the production of coloring materials and inks.

Applying pyrolysis-gas chromatography/mass spectrometry to the identification of oriental lacquers: study of two lacquered shields.

Oriental lacquers have been used as coating materials for thousands of years for wooden, ceramics, leather and metal objects. Lacquers are natural polymers obtained from three species growing in different regions of Asia: Rhus vernicifera (China, Japan and Korea); Rhus succedanea (Vietnam and Taiwan); and Melanorrhoea usitate (Myanmar and Thailand). The identification of lacquer films is important for conservation and restoration purposes, as well as for art history studies because it may help in determining the origin of the lacquered objects.