AM_Heulandite-Ca_6 Formula: Na.86 K.2 Ca1.325 Ba.015 Sr.435 (Al4.46 Si13.54) O49 H26 Name: Heulandite-Ca Unit cell: 17.124 17.376 7.237 90.0 116.93 90.0 , V=1919.84 Space group: C12/M1 (12)

Comodi P , Gatta G D , Zanazzi P F , European Journal of Mineralogy , 13 (2001) p.497-505, High-pressure structural behaviour of heulandite, Sample: P = 3.4 GPa