AM_Kentrolite
Formula: Pb2 Mn1.68 Fe.32 Si2 O9
Name: Kentrolite
Unit cell: 6.961 11.018 9.964 90.0 90.0 90.0 , V=764.20
Space group: PBCN (60)

Moore P B , Sen Gupta P K , Shen J , Schlemper E O , American Mineralogist , 76 (1991) p.1389-1399, The kentrolite-melanotekite series, 4Pb2(Mn,Fe)2O2[Si2O7]: Chemical, crystallographic relations, lone-pair splitting, and cation relation to 8URe2