AM_Pigeonite_4 Formula: O6 Si2 Mg.921 Fe.835 Mn.027 Ca.195 Name: Pigeonite Unit cell: 9.707 8.941 5.247 90.0 108.48 90.0 , V=431.91 Space group: P121/C1 (14)

Camara F , Carpenter M A , Domeneghetti M C , Tazzoli V , American Mineralogist , 88 (2003) p.1115-1128, Coupling between non-convergent ordering and transition temperature