Fire impact on the mausoleum of Zein El-Deen Josef in Cairo

ABSTRACT Al-Qadiriyah mosque was built in 1297A.D. (i.e. 697 after Hegira [AH]) and it is one of the ancient Islamic monuments belonging to the Marine Mamluk era (ad 1250–1382; i.e. 648–784AH) It includes the mausoleum of its founder Al-Sheikh Zein El-Deen Josef. The inner walls of the mausoleum are covered with marble cladding of three different colors. Recently the mosque was severely damaged by a fire. The aim of this study is to investigate fire effect on marbles through the application of in situ investigation and laboratory techniques. The morphological analysis proved that the change of color, micro-cracking, breaking, scaling and discoloration are the common deterioration patterns from the effects of fire. Color change is the most visible pattern at both brown and black marbles. Moreover, the white marble is the most affected variety by micro-cracking and breaking patterns, while the black marble is the exclusive affected variety by scaling. Petrographic analysis using polarizing optical microscope (OM) and mineralogical analysis by both X-ray diffraction (XRD) and scanning electron microscope (SEM) were carried out. Change of texture and inner structure, color change, the formation of new mineral phases and disappearance of minerals were distinguished associated to the fire impact. Analysis of coating material of discoloration was performed by Fourier transform infrared spectroscopy technique (FTIR), which revealed a correspondence in the absorption bands of the original material spectrum with respect to the modern shellac. It is also recognized that the most probable temperature range to which the mausoleum marbles were subjected during the fire was 550°C–800°C.