AM_Pentagonite Formula: Si4 Ca V O15 H8 Name: Pentagonite Unit cell: 10.386 14.046 8.975 90.0 90.0 90.0 , V=1309.29 Space group: CCM21 (36)

Evans H T , American Mineralogist , 58 (1973) p.412-424, The crystal structures of cavansite and pentagonite