'Dust on His Head' in the Bible

Now when David had come to the top of the slope, where they gave worship to God, Hushai the Archite came to him in great grief with dust on his head:

Now when Mordecai saw what was done, pulling off his robe, he put on haircloth, with dust on his head, and went out into the middle of the town, crying out with a loud and bitter cry.