AM_Laumontite_1 Formula: Si4 Al2 O15.522 Ca H14 Name: Laumontite Unit cell: 14.74716 13.06601 7.55735 90.0 112.0399 90.0 , V=1349.78 Space group: C12/M1 (12)

Fridriksson T , Bish D L , Bird D K , American Mineralogist , 88 (2003) p.277-287, Hydrogen-bonded water in laumontite I: X-ray powder diffraction, study of water site occupancy and structural changes in laumontite, during room-temperature isothermal hydration/dehydration, Sample: P = 16.4 mbar PH2O