The mosaic panel is believed to be the only one in the world, the antiquities authority said, citing the quality of its preservation given its age and its craftsmanship indicating Christian origins.
"It's a unique find, a piece of art," Joseph Patrich, professor of archaeology at the Hebrew University in Jerusalem. "It's in its original state," Patrich said, because the panel fell face down, protecting its green, blue and gold facade from debris and damage.
The mosaic was discovered in 2005 in Caesarea, an ancient city on the Mediterranean coast known for its ancient Roman, Byzantine and Crusader ruins. During excavation of a palace, the original floor was exposed, revealing the panel lying face down in one of the larger paved mosaics.
Detached from the floor in a risky operation, conservationists were then faced with the task of removing centuries of dirt and fire damage from the destruction of the palace in the late Byzantine Era in late 6th or early 7th century A.D., Patrich said.
The mosaic is particularly important because the small colored tiles forming it features two styles of tiling: gold glass and the more traditional multicolored, opaque glass commonly associated with mosaics, he said. The tiles depict two motifs: crosses and eight-petalled rosettes.
The owner and origin of the palace in which the panel was found is unclear - all that is known is that the residents were likely Christian, experts said. The original role of the restored panel also remains unknown.