"... it must be assumed that the floors of each level of the heavens were composed of a different type of stone, and that there was open space between each stone floor, just as there is open space between the earth's surface and the Lower Heavens. Furthermore, it may be assumed that each stone floor was visible from below and served as a roof for the region below. These assumptions find support in a parallel from Exodus 24:9-10, where the floor of heaven is apparently built of blue brick ... Hebrew 'sapphire', which is equated with Greek sapheiros and Latin sappirus, is a blue stone and has often been identified with lapis-lazuli. Thus, the blue brick floor of heaven in Exodus, when seen from below, may be identified with the blue background color of the sky on clear days and the darker blue of the clear night sky. In KAR 307, Anu and the Igigi apparently stand on luludanitu-stone and saggilmud-stone floors of the Upper and Middle Heavens, just as the God of Israel stands on a blue 'sapphire' brick heavenly floor in Exodus ..."