'Soot' in the Bible

Then the LORD told Moses and Aaron, "Take handfuls of soot from a kiln, and let Moses throw it into the air in front of Pharaoh.

The soot will become dust over the entire land of Egypt, and it will become boils erupting into sores on people and animals throughout the land of Egypt."

So they took soot from the kiln and stood before Pharaoh. Then Moses threw it into the air,and it became boils producing running sores on people and animals.