Archaeometry of western side Mihrab of northern Shabistan of Kashan's Jami mosque

Jami’ mosque of Kashan is one of the oldest recorded sites of Islamic era. This mosque has three stucco Mihrabs; one in the dome and two in the north Shabistan of the mosque. In order to determine the date of the main Mihrab, samples of the bricks were taken for Thermoluminescence (TL) dating. In addition, sampling was accomplished for identification of the pigment and stucco used in the Mihrab. Polarized light microscope (PLM) and X-ray diffraction (XRD) were used for identification of pigments and the mortar and plaster components, and a scanning electron microscope with energy dispersive X-ray (SEM-EDX) for elemental analysis of the samples. The result of Thermoluminescence (TL) dating of brick sample of the upper Mihrab addressed 550±20 years ago as construction date of the Mihrab. Results also revealed that in the decorations, lapis lazuli and red lead had been used for creating blue and red colors.