It is very soluble in water, and so can only be found in dry regions: however, in can still 
effloresce  (lose water of crystallisation )
Kaynak: MendoziteThe heptahydrate crystals 
effloresce  in warm dry air.  Heptahydrate crystals also oxidize in air to form the sulfate.  The anhydrous form
Kaynak: Sodium sulfiteBoth the hepta- and the decahydrate 
effloresce (lose water) in dry air and are partially transformed into the monohydrate thermonatrite
Kaynak: NatronParts : Allegro (Reviresce, 
effloresce, pacisolea) XXX.  Recitativo (Aptate tympana) XXXI.  Aria and Chorus (Vive, regna) XXXII.  Aria.
Kaynak: Sub olea pacis et palma virtutis