While the marble and mosaics on the outside were almost totally replaced during the Ottoman period, the majority of the inside appears as it originally did. Many restorations have taken place on the mosaics, but most of the restorations remained true to the originals. There is no exact repetition of any designs, but there are similar designs each with a personal touch. The mosaics decorate the upper portions of the piers, spandrels, and the drum. Trees tend to cover the tall, rectangular portions while scrolls adorn the majority of the square areas.
Vegetal motifs are the primary design on the outer arcade.
The inner arcade is decorated with designs of Byzantine and Sasanian crowns, breastplates, and jewels. No pre-Islamic artist would have mixed royal symbols and vegetal design, although vegetal design alone is on the outer arcade. It is possible that, like the Christological symbols showing power over Christianity, the royal designs function to show power and domination over the preceding dynasties. It is thought that, in addition to the soft light allowed in by the stained glass windows, thousands of candles were used to illuminate the interior.