AM_Alunite_2
Formula: S2 Al2.967 O14.063 K.805 Na.132 H6
Name: Alunite
Unit cell: 6.9741 6.9741 17.19 90.0 90.0 120.0 , V=724.07
Space group: R-3M (166)

Majzlan J , Speziale S , Duffy T S , Burns P C , Physics and Chemistry of Minerals , 33 (2006) p.567-573, Single-crystal elastic properties of alunite, KAl3(SO4)2(OH)6