Nepheline Gatta G D, Angel R J American Mineralogist 92 (2007) 1446-1455 Elastic behavior and pressure-induced structural evolution of nepheline: Implications for the nature of the modulated superstructure Locality: intrusive aplite of Snipe River, Tambani, Nyasaland, Malawi Sample: P = 4.130 GPa _database_code_amcsd 0004425 9.7178 9.7178 8.2030 90 90 120 P6_3 atom x y z occ Uiso K 0 0 .0041 .54 .0190 NaK 0 0 .0041 .24 .0190 CaK 0 0 .0041 .03 .0190 Na .55760 .99930 .5064 .0182 AlT1 2/3 1/3 .71222 .0087 SiT2 2/3 1/3 .31158 .0075 SiT3 .91817 .67174 .82475 .0091 AlT4 .91775 .67115 .19370 .0075 O1 2/3 1/3 .5059 .0406 O2 .00071 .69849 .0042 .0144 O3 .8336 .47374 .2310 .0207 O4 .8456 .48771 .7642 .0166 O5 .77691 .71442 .8345 .0126 O6 .7850 .7392 .1875 .0135