AM_Natrojarosite
Formula: Na.69 K.29 Fe3 S2 O14 H6
Name: Natrojarosite
Unit cell: 7.3101 7.3101 16.7658 90.0 90.0 120.0 , V=775.89
Space group: R-3M (166)

Basciano L C , Peterson R C , American Mineralogist , 93 (2008) p.853-862, Crystal chemistry of the natrojarosite-jarosite and natrojarosite-hydronium, jarosite solid-solution: A synthetic study with full Fe site occupancy, Locality: synthetic, Sample: N