AM_Arsenoclasite
Formula: Mn5 As2 (O12 H4)
Name: Arsenoclasite
Unit cell: 18.29 5.75 9.31 90.0 90.0 90.0 , V=979.11
Space group: P212121 (19)

Moore P B , Molin-Case J , American Mineralogist , 56 (1971) p.1539-1552, Crystal chemistry of the basic manganese arsenates: V. Mixed manganese, coordination in the atomic arrangement of arsenoclasite