Techniques and Changes of Stucco Decorations in Iranian Architecture from 7th to 9thCentury Hijry Qamari

7th to 9thCentury Hijry Qamari is considered a significant period in art history of Iran، during which many arts had undergone notable changes relying on previous era (Seljuk and khwarazmshahian). One of the notable arts in that period was the art of stucco from which many examples have survived. Using plaster in architectural decorations has reaches its zenith during these centuries and have been executed with more projection and more complicated designs. In order to identify stucco decoration techniques and their changes and developments، through observation and investigation using descriptive- ­­analytical method، some of the existing examples have been studied. Building the high relief stucco altars at the the beginning of the 7th century and the bas relief stucco decorations at the end of the 8th century Hijri Qamari led to a significant change in this art and the creation of masterpieces in this period. Stucco decorations in this era are categorizable by the “projection” and the “modeling technique”. On the whole there are eleven techniques for stucco decoration in these centuries from which High Relieve Stucco، Reticulated (Moshabbak)، Patchwork Stucco (Vaslehiee) and Gilding are particular characteristics of stucco from7th to 9thCentury Hijry Qamari.