It tells you right here at Exodus 24:9-11
"9 Moses and Aaron, Nadab and Abihu, and the seventy elders of Israel went up 10 and saw the God of Israel. Under his feet was something like a pavement made of lapis lazuli, as bright blue as the sky. 11 But God did not raise his hand against these leaders of the Israelites; they saw God, and they ate and drank."