Gaylussite is subject to dehydration which can cause cloudiness and deterioration and should therefore be stored in a sealed container. Color is colorless, white or yellowish. Luster is vitreous. Crystals are transparent to translucent. Crystal Habits include intricately faceted prismatic to tabular crystals, but also massive and encrusting.
Cleavage is perfect in two directions.
Fracture is conchoidal. Hardness is 2 - 3. Streak is white. Associated Minerals include pirssonite , northupite , trona , analcime and halite .