Thematic Bible: Natural rocks sometimes used as

Gideon went in, and made ready a kid, and unleavened cakes of an ephah of meal: the meat he put in a basket, and he put the broth in a pot, and brought it out to him under the oak, and presented it. The angel of God said to him, "Take the meat and the unleavened cakes, and lay them on this rock, and pour out the broth." And he did so. Then the angel of the LORD put forth the end of the staff that was in his hand, and touched the flesh and the unleavened cakes; and there went up fire out of the rock, and consumed the flesh and the unleavened cakes; and the angel of the LORD departed out of his sight.

So Manoah took the young goat and a grain offering, and offered it on the rock to the LORD, who works wonders. Then the angel did a wonderful thing as Manoah and his wife looked on. For it happened, when the flame went up toward the sky from off the altar, that the angel of the LORD ascended in the flame of the altar. And Manoah and his wife looked on, and they fell on their faces to the ground.