AM_Neptunite_3 Formula: Na2 K Li Ti2 Fe2 Si8 O24 Name: Neptunite Unit cell: 16.426 12.532 9.995 90.0 115.51 90.0 , V=1856.89 Space group: C1C1 (9)

Kunz M , Armbruster T , Lager G A , Schultz A J , Goyette R J , Lottermoser W , Amthauer G , Physics and Chemistry of Minerals , 18 (1991) p.199-213, Fe, Ti ordering and octahedral distortions in acentric neptunite:, temperature dependent X-ray and neutron structure refinements, and Mossbauer Spectroscopy, Sample: T = 493 K