rock dust



a crushed limestone sprayed on surfaces in mines to make coal dust incombustible in case of a gas explosion.

Origin of rock dust

First recorded in 1930–35 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for rock dust

  • The flame of the explosion can't pass through and the fire can't jump a rock-dust barrier.

    The Boy With the U.S. Miners|Francis Rolt-Wheeler
  • Rain and rock-dust had smeared all things alike in this gray roasting shambles.

  • Little clouds of rock-dust rose above the bear, in front of him, behind him, and below him.

    Tenting To-night|Mary Roberts Rinehart