Answer: effloresce

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