AM_Chiavennite Formula: Ca Mn Be2 Si5 O17 H6 Name: Chiavennite Unit cell: 8.729 31.326 4.903 90.0 90.0 90.0 , V=1340.70 Space group: PNAB (60)

Tazzoli V , Domeneghetti M C , Mazzi F , Cannillo E , European Journal of Mineralogy , 7 (1995) p.1339-1334, The crystal structure of chiavennite