Answer: efflorescing

AnswerCrossword Clue
efflorescing(of a surface) Become covered with salt particles
efflorescingEFFLORESCE, to flower; burgeon; (chem.) to become powder when exposed to air
efflorescing(of salts) Come to the surface of brickwork, rock, or other material and crystallize there
efflorescing(of a substance) Lose moisture and turn to a fine powder upon exposure to air
efflorescingReach an optimum stage of development; blossom