1261–1262
Perhaps the most important contribution of Muslim potters, the application of luster to a ceramic surface was not limited to vessels. As early as the ninth century, this costly technique was applied to wall tiles to distinguish parts of buildings. In the eastern Islamic lands during the medieval era, the use of colored tiles — decorated with luster but with other techniques as well — increased in complexity and scope. In both religious and secular buildings, large surface areas came to be sheathed in brilliant ceramic revetments. The use of glazed ceramics for architectural decoration continued into the early modern era, culminating in the great monuments of the Safavid and Ottoman Empires. The luster tiles gathered here would have been integrated into the decoration of buildings of the Seljuk-Atabeg (1037–c. 1220) and Ilkhanid (1256–1335) periods. Although the star tiles bear self-contained designs, they were intended to interlock with cruciform tiles in a grid. Three of the tiles feature inscriptions. The two large stars, which were probably intended for the interior of a religious shrine, reproduce verses from the Qurʾan in Arabic. The tile with figural imagery bears fragments of poetry in Persian, demonstrating the revival of Persian as a literary language in the medieval era.