AM_Turtmannite Formula: Mg26.64 Mn119 V14.28 As6.72 Si16.56 O291.6 Name: Turtmannite Unit cell: 8.259 8.259 204.3 90.0 90.0 120.0 , V=12068.52 Space group: R-3C (167)

Brugger J , Armbruster T , Meisser N , Hejny C , Grobety B , American Mineralogist , 86 (2001) p.1494-1505, Description and crystal structure of turtmannite, a new mineral with a, 68 Angstrom period related to mcgovernite, Note: z-coordinate of Mn12 has been modified