AM_Richterite_2 Formula: Si8 (Mg2.75 Ni2.25) (Na Ca) K O24 H2 Name: Richterite Unit cell: 10.0492 17.975 5.2661 90.0 104.904 90.0 , V=919.24 Space group: C12/M1 (12)

Della Ventura G , Robert J-L , Raudsepp M , Hawthorne F C , American Mineralogist , 78 (1993) p.633-640, Site occupancies in monoclinic amphiboles: Rietveld structure refinement of, synthetic magnesium cobalt potassium richterite, Sample: KNi40, Atomic parameters from ICSD