The Propylaea of Xerxes - Perseopolis

There is relatively little of the fanciful in our restorations of Persian buildings, because the rock-cut tombs in the hillside still reproduce in relief the vanished architecture of the plain below. Thus while there is no direct evidence that a frieze of lions in enamelled brick actually ran round the cornice of the Propylaea, we know that it would certainly not have been out of place. The lintels, door-posts, and columns were of uncemented stone, the beams of wood, and the remainder in brick.

From Wonders of the Past