Mora, L., Mora, P., and Philippot, P. 1984. Conservation of Wall Paintings. Durability: Visual changes in the aging tests samples were not apparent. It is hoped that SEM analysis can be an aid in determining if durability has been enhanced. The refractive indices (RI) of the painted surfaces tested were unaltered. Applications of acids of varying strengths and concentrations were applied to the plaster and marble samples.
Burnstock, A. 1997. «Introduction to the methods for the analysis of pigments an plasters — An overview.» Paper presented at the conference The Analysis of Pigments and Plasters. Research Commissioned by Her Majesty’s Inspectorate of Pollution. Solutions, such as lime water, believed to strengthen decaying stone by the addition of sound calcium carbonate, have not been proven to be entirely effective.
Crystal size and morphology are different in the treated samples. Theories ranging from the activity of lichen and other micro-organisms to electrical storms as the source of calcium oxalate (Ford, et al. 1994). Where the patina is found Scialbatura in its natural form may be the «skin» that is found on unworked stone. Both are chemically pure, although impurities are bound up in the crust during their formation. Salts deep within the stone cannot be washed away and if they continue to accumulate damage may occur.