Fragment of a Luster-Painted Open Vessel 9th-10th century This ceramic fragment was excavated in Ctesiphon, the Sasanian metropolis and administrative capital conquered by Arab Muslim armies in 637. The city was known in Arabic as al-Madain, or "the cities", for its extended area. Arab historians indulge in describing al-Madain/Ctesiphons grand monuments, which obsessed Muslim rulers and may have acquired a symbolic meaning related to its imperial past. This was the case of the Taq-i Kisra, an impressively-sized ivan (a vaulted hall with one side open) partially dismantled to reuse its bricks in caliphal buildings in the new capital Baghdad. Finds like this fragment attest to the continued occupation of Ctesiphons urban area in the early Islamic period. Luster was an innovative technology developed by Iraqi-based craftsmen in the 9th century, as was this kind of opacified glaze. The glaze was obtained with different techniques, such as the addition of tin oxide, through undissolved