AM_Beryl_18 Formula: Si6.003 Be2.595 Li.393 Al2.009 O18 Na.239 Cs.131 Rb.002 Name: Beryl Unit cell: 9.2155 9.2155 9.2291 90.0 90.0 120.0 , V=678.78 Space group: P6/MCC (192)

Aurisicchio C , Fioravanti G , Grubessi O , Zanazzi P F , American Mineralogist , 73 (1988) p.826-837, Reappraisal of the crystal chemistry of beryl, Sample: 19, Note: U(1,2) for Na/Cs/Rb altered to match symmetry constraints.