Verses with the word gravel in the Old Testament (3 verses):

Proverbs 20:17
Bread of deceit is sweet to a man; but afterwards his mouth shall be filled with gravel.

Isaiah 48:19
Thy seed also had been as the sand, and the offspring of thy bowels like the gravel thereof; his name should not have been cut off nor destroyed from before me.

Lamentations 3:16
He hath also broken my teeth with gravel stones, he hath covered me with ashes.