The destructive action of copper pigments, irongall inks and metal coatings on paper and parchment present great problems to libraries and collections of graphic art. Conservation of damaged objects by inhibition of the degradation process is not yet possible. With the aim of developing such methods of treatment, investigations were carried out concerning interactions between transition metal ions and cellulose. One source of severe damage to illuminated manuscripts or colored etchings is corrosive green copper pigments, especially verdigris (copper acetate). The analytical findings achieved so far show a decay of both pigment and paper carrier marked by extremely low degress of polymerization of the cellulose and a high copper content of the paper fibers. Paper fibers from damaged objects have disintegrated to a large extent in the interior and show central cavities. Degradation products of cellulose resulting from Fehling's reaction were definitely detectable in original samples. Possible chemical mechanisms of this destructive phenomenon are discussed. Samples of paper and parchment affected by irongall inks were investigated by means of scanning electron microscopy with respect to the distribution of transition metalions and to the typical morphological appearance of the destruction process. As far as paper samples are concerned, a characteristic distribution of iron, which was the only transition metal found, could be shown in the way that there is an accumulation of this element in the middle of the paper fleece in extremely damaged samples. The degree of damage correlates clearly with the concentration of iron. In the area around character in undamaged sections, the amount of iron decreases rapidly with the distance from the point of application of the ink. Analyses of overall dark stained parchment samples revealed the occurrence of iron and copper. In comparison to the fibrillar network of untreated parchment the decayed brittle samples showed a total loss of fibrillar structures. See also AATA 18-1151, 19-1244, and 21-338 for related paper.