'Dust' in the Bible

The Lord said to Moses, "Tell Aaron, 'Extend your staff and strike the dust of the ground, and it will become gnats throughout all the land of Egypt.'"

They did so; Aaron extended his hand with his staff, he struck the dust of the ground, and it became gnats on people and on animals. All the dust of the ground became gnats throughout all the land of Egypt.

It will become fine dust over the whole land of Egypt and will cause boils to break out and fester on both people and animals in all the land of Egypt."