AM_Tschermakite Formula: Na.88 K.1 Mg3.66 Fe.47 Al2.37 Cr.2 Ca1.8 Si6.44 O24 H2 Name: Tschermakite Unit cell: 9.8059 17.9721 5.3012 90.0 105.063 90.0 , V=902.14 Space group: C12/M1 (12)

Abdu Y A , Hawthorne F C , The Canadian Mineralogist , 47 (2009) p.917-926, Crystal structure and Mossbauer spectroscopy of tschermakite from the ruby, locality at Fiskenaesset, Greenland, Locality: Fiskenaesset, Greenland