THE ROLE OF CONSERVATION PROCESSES IN REVEALING AND DISPLAYING OF BLAZONS AND DECORATIVE PATTERNS ON LEAD-BRASS GRILLES IN THE MOSQUE OF AMIR QAJMAS AL-ISHAQI, CAIRO- EGYPT

The Prince Qajmas Al-Ishaqi Mosque, known as Abu Hariba Mosque, contains windows with metal grilles covered with thick layers of corrosion and dust that completely hide their features. Various investigations and analyses were conducted on these grilles to identify their components and the corrosion compounds that cover their surfaces. Stereomicroscope, metallographic, scanning electron microscope, X- Ray diffraction and EDX unit were used. Examinations show that the surface layers consist of clay minerals, quartz and corrosion products in various colours. The mineral composition of the samples was determined by X –Ray Diffraction Analysis. The analysis revealed the presence of cuprite, malachite, atacamite, and paratacamite as Corrosion products, in addition to quartz and kaolinite. The grilles were made by casting from a lead - brass alloy, which is an alloy consisting of copper and zinc in addition to lead. The various conservation processes, including mechanical and chemical cleaning, resulted in the discovery and display of the blazon of Prince Qajmas Al-Ishaqi, the founder of the mosque, as well as various decorations. The outer surface was also protected by applying protective layers to preserve these windows with metal grilles from deterioration again using a solution of Paraloid B 82 dissolved in toluene at a concentration of 3%. The current study seeks to uncover the conservation processes that were carried out in revealing and displaying of blazons and decorative patterns on lead-brass grilles in the Prince Qajmas Al-Ishaqi Mosque in Cairo, Egypt.