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Some of the best examples of later Islamic mosaics were produced in Moorish Spain. The golden mosaics in the mihrab and the central dome of the Great Mosque in Corduba have a decidedly Byzantine character. They were made between 965 and 970 by local craftsmen, supervised by a master mosaicist from Constantinople, who was sent by the Byzantine Emperor to the Umayyad Caliph of Spain. The decoration is composed of colorful floral arabesques and wide bands of Arab calligraphy. The mosaics were purported to evoke the glamour of the Great Mosque in Damascus, which was lost for the Umayyad family.

Who sent the master mosaicist to Spain?
the Byzantine Emperor