AM_Heulandite_4 Formula: Si18 Al.412 Na.26 O39.1 H25.12 Name: Heulandite Unit cell: 17.608 17.656 7.414 90.0 116.42 90.0 , V=2064.18 Space group: C12/M1 (12)

Wust T , Stolz J , Armbruster T , American Mineralogist , 84 (1999) p.1126-1134, Partially dealuminated heulandite produced by acidic REECl3 solution: A chemical, and single-crystal X-ray study, Sample: DEHY378