Structural study and Laboratory Survey of the Decoration of Kaboudani Mosque in Khaf

Khaf Kaboudani historical complex is one of the most important monuments of the Timurid era. This complex was built during the heyday of this region, around the tomb of the famous mystic of this period, Sultan Mahmoud Kaboudani. This historical complex, of which only a ruin remains today, was once a complete complex, including a shrine, mosque and water reservoir. The interior of the buildings of this complex, as is the tradition of Timurid architecture, is decorated with various types of architectural decorations, such as wall painting, Tokhmeh daravari, Stucco decoration, Rasmibandi and Mogharnaskari. Among these architectural decorations, the one that attracts the most attention is wall painting and Tokhmeh daravari decoration that the interior of Kaboudani mosque is where the interior surfaces of the mosque are decorated with beautiful decoration with geometric motifs in orange, red, purple, blue, ocher and white. Due to the importance of this historical complex left over from the Timurid era and the lack of study on the one hand and the deteriorating condition of its decorations, on the other hand, in this research, an attempt was made to study and identify the decoration of this historic mosque and the colors used in it experimentally and with the help of laboratory methods. Laboratory study of colored Stucco of this building, with various methods of instrumental analysis, such as X-ray diffraction (XRD), X-ray fluorescence (XRF), Scanning electron microscope in combination with energy dispersive X-ray microanalysis ((SEM-EDS), showed that "Gach-e-Zendeh" has been used in the plaster decorations and a thin layer of "Gach-e-koshte" has been used under substrate wall painting. Analysis of the pigments used in the decoration of this building by instrumental methods, indicated that all the colors used were inorganic mainly and in the range of red colors from ocher, from chalk as white and in blue from natural Lapis Lazuli Used.