AM_Heulandite-Na_1 Formula: Na2.84 Ca.76 (Al4.3 Si13.7) O48.38 H54 Name: Heulandite-Na Unit cell: 17.677 17.931 7.426 90.0 116.47 90.0 , V=2107.04 Space group: C12/M1 (12)

Yang P , Armbruster T , Journal of Solid State Chemistry , 123 (1996) p.140-149, Na, K, Rb and Cs exchange in heulandite single-crystals: X-ray structure, refinements at 100 K, Sample: T = 100 K, Locality: Nasik, India