Alumoakermanite Wiedenmann D, Zaitsev A N, Britvin S N, Krivovichev S V, Keller J Mineralogical Magazine 73 (2009) 373-384 Alumoakermanite, (Ca,Na)2(Al,Mg,Fe2+)(Si2O7), a new mineral from the active carbonatite-nephelinite-phonolite volcano Oldoinyo Lengai, northern Tanzania Locality: Oldoinyo Lengai, northern Tanzania _database_code_amcsd 0020206 7.7661 7.7661 5.0297 90. 90. 90. P-42_1m atom x y z occ Uiso U(1,1) U(2,2) U(3,3) U(1,2) U(1,3) U(2,3) Ca1 .66382 .83618 .49132 .76 .0182 .0204 .0204 .0138 .0063 -.0016 -.0016 Na1 .66382 .83618 .49132 .24 .0182 .0204 .0204 .0138 .0063 -.0016 -.0016 Al2 0 0 0 .50 .0125 .0111 .0111 .0154 0 0 0 Fe2 0 0 0 .30 .0125 .0111 .0111 .0154 0 0 0 Mg2 0 0 0 .20 .0125 .0111 .0111 .0154 0 0 0 Si .85952 .64048 .05699 .01169 .0122 .0122 .0106 .0014 .0002 .0002 O1 .5 0 .8240 .0237 .0293 .0293 .012 -.017 0 0 O2 .85812 .64188 .7411 .0246 .0301 .0301 .0136 .0063 .0025 .0025 O3 .9172 .81825 .2026 .0257 .0372 .0186 .0214 -.0074 .0053 -.0045