The Use of Analytical Methods in Evaluation of Coptic Wall Paintings Conservation - A Case Study

Egypt has a lot of ancient monasteries and churches, which were decorated with different kinds of wall paintings. Structure of these wall paintings consists of support, plaster and painting layers. Paintings deterioration is primarily due to physicochemical, natural and human factors. The most detrimental factors are bat patches, old varnish and organic waste of birds. All these lead to the gradual disappearance of paintings. Modern technology of conservation is focused on application of new materials for cleaning of wall paintings. Here we report on the use of enzymes, for cleaning surface of coptic wall paintings. Analytical techniques such as particle induced X-ray emission, Fourier transform infrared and optical microscopy were used to evaluate the enzymatic cleaning processes of coptic wall paintings and to identify the chemical composition of red, yellow and white pigments. Particle induced X-ray emission results indicated that there is no change in the chemical composition of the materials and pigments due to enzymatic cleaning. Fourier transform infrared and optical microscopy results confirmed the stability of organic medium before and after treatment of different kind of patches.