AM_Richterite_28 Formula: Si8 Mg5 (Ca Na) K2 O24 Name: Richterite Unit cell: 10.0547 17.997 5.2746 90.0 104.832 90.0 , V=922.66 Space group: C12/M1 (12)

Hawthorne F C , Della Ventura G , Robert J-L , Welch M D , Jenkins D M , American Mineralogist , 82 (1997) p.708-716, A Rietveld and infrared study of synthetic amphiboles along the, potassium-richterite-tremolite join, Sample: Kr100