'Soot' in the Bible

Then the Lord said to Moses and Aaron, “Take handfuls of soot from the brick kiln, and let Moses throw it toward the sky in the sight of Pharaoh.

So they took soot from the kiln, and stood before Pharaoh; and Moses threw it toward the sky, and it became boils erupting in sores on man and animal.

Their appearance is [now] blacker than soot [because of the prolonged famine];They are not recognized in the streets;Their skin clings to their bones;It is withered, and it has become [dry] like wood.