AM_Heulandite-Ca_7 Formula: Na.86 K.2 Ca1.325 Ba.015 Sr.435 (Al4.46 Si13.54) O49 H26 Name: Heulandite-Ca Unit cell: 17.774 17.824 7.438 90.0 116.38 90.0 , V=2111.01 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 = .0001 GPa (after compression)