Chalk Dust

Chalk

Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed under the sea by the accumulation and lithification of hard parts of organisms, mostly microscopic plankton, which had settled to the sea floor. Chalk is common throughout Western Europe, where deposits underlie parts of France, and steep cliffs are often seen where they meet the sea in places such as the Dover cliffs on the Kent coast of the English Channel.

Dust

Dust is made of fine particles of solid matter. On Earth, it generally consists of particles in the atmosphere that come from various sources such as soil lifted by wind, volcanic eruptions, and pollution.

chalk

Noun

1. A soft, white, powdery limestone (calcium carbonate, CaCO3).
2. A piece of chalk, or nowadays processed compressed gypsum (calcium sulfate, CaSO4), that is used for drawing and for writing on a blackboard (chalkboard).

Verb

1. To apply chalk to anything, such as the tip of a billiard cue.
2. To record something, as on a blackboard, using chalk.

dust

Noun

1. Fine particles.

Verb

1. To remove dust from.
2. To remove dust; to clean by removing dust.