Volume 36, Issue 2 -

Golden pigments are among the most common colourants used in Persian illuminated manuscripts. In this research, golden pigments were investigated in three eighteenth- to nineteenth-century manuscripts. Initially, scanning electron microscopy–energy dispersive spectrometry analyses showed that different kinds of metallic pigments were present and some of them were ternary alloys made up of copper, zinc and tin, hence copper-based alloys were ascertained as cheap alternatives to gold. Discolouration of the pigment was observable through alteration of the metallic pigments to greenish residues in the manuscripts. Subsequently, the greenish products in the golden pigments were studied by Raman spectroscopy. Copper carboxylates were recognized as degradation products. We inferred that the alteration is a consequence of the interaction between copper alloy pigments and carboxylic acids in conditions of high humidity. Moreover, more progressive degradation has caused the discolouration, brittleness and gradually crumbling of the paper in the painted areas. Signs of damages in the paper were comparable with decomposition of the paper by green copper pigments such as verdigris in historical documents and miniatures.

This article describes the endangered situation of Cham manuscripts in Vietnam. Cham are a minority people in Vietnam who used to have their own kingdom called Champa that lasted from the seventh century until 1832, when Champa was eliminated by the Vietnamese. For hundreds of years, Cham people have produced many palm-leaf and paper manuscripts recording their religious teachings, culture, and history. About 600 Cham manuscripts have been collected by institutions in France and Vietnam. Yet, there are a few thousand more manuscripts still available in Cham communities located in Central Vietnam. Most of the manuscripts kept by these communities are however in poor physical condition and urgently need to be better preserved. This article first provides background information on Cham people and Cham manuscripts. Next, it describes the current preservation of Cham manuscripts in Vietnam, explaining why these invaluable materials of the Cham cultural heritage are in an endangered situation. Finally, it briefly discusses solutions for the preservation of Cham manuscripts in Vietnam. Information used in the article is mainly based on observation from two recent field trips to Vietnam by the author.

Colour analysis contributes to better characterization and appraisal of cultural objects such as historic written documents, because measurements of their colour and chromatic differences may facilitate suitable assessment and control of their state of preservation. This paper describes a colorimetric study undertaken on the parchment binding and the paper leaves of a medieval manuscript notebook (1382–1400), now kept in the Archives of the Royal Chancellery of Granada, Spain. The aim of the study was a physical characterization of the notebook and an evaluation of the chromatic changes caused by its ageing. To this end we measured the colour of the binding and the pages of the document and evaluated the differences in colour between various points on the binding. As a result of this analysis we detected significant alterations in colour between protected areas of the binding, which retained their original colour, and others exposed to the effects of damaging agents such as light, humidity or dirt. These chromatic changes manifest in a decrease in brightness L *, a slight increase in the C * ab chroma and a variation in hue tending toward red, with a decrease in the values of the hue angle h ab .

Verdigris (copper acetate) has been frequently used in manuscripts, early printed books and on maps. Dyes and pigments from plants have been added to modify the colour. Depending on the mode of application, paper quality, size and environmental factors like light and humidity the green colour of verdigris can discolour to brown tones and chemically damage the paper carrier. Treatment options include the application of solutions to stabilize cellulose chemically and mechanical reinforcement of the brittle or broken papers with Japanese paper and adhesives. Samples of copper acetate in gum arabic on rag paper were pre-aged to induce moderate degradation of cellulose. Deacidification, antioxidant and complexing solutions were applied by airbrush or by brush. Japanese tissue papers were coated with different aqueous or non-aqueous adhesives and applied by activation with water, ethanol or heat. The effect of the coated tissue papers was visually and mechanically evaluated before and after ageing. This contribution gives an overview of the project and focuses on mechanical stabilization and the implications of results for conservation.