A STUDY OF THE DETERIORATION OF EGYPTIAN LIMESTONE SCULPTURE
S.M. Bradley, & A.P. Middleton
ABSTRACT—The decay of some Egyptian limestone sculptures during storage in a museum environment has been investigated using a variety of analytical techniques. These have included the chemical determination of soluble salts, gravimetric estimation and analysis by X-ray diffraction of the acid insoluble fraction, petrographic examination, observation and analysis in the scanning electron microscope and determination of porosity using mercury porosimetry. The results suggest that the mineralogy of the limestone, in particular the clay content, and the level and nature of soluble salts, particularly of soluble nitrates, are important factors in determining the nature and degree of any decay. The results also indicate that different types of limestone were used at different sites which accounts for the high proportion of badly deteriorated sculpture attributed to sites around Thebes and Abydos. This also suggests a possible technique for determining the provenance of Egyptian limestone objects.