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 = 1.967 GPa _database_code_amcsd 0004424 9.8499 9.8499 8.2838 90 90 120 P6_3 atom x y z occ Uiso K 0 0 .0029 .54 .0268 NaK 0 0 .0029 .24 .0268 CaK 0 0 .0029 .03 .0268 Na .55578 .99782 .5066 .0217 AlT1 2/3 1/3 .7049 .0096 SiT2 2/3 1/3 .3107 .0113 SiT3 .91197 .66799 .82507 .0092 AlT4 .91316 .67064 .19626 .0114 O1 .6621 .2962 .5011 1/3 .0238 O2 .98771 .69126 .0055 .0205 O3 .8293 .47474 .2310 .0222 O4 .8432 .48988 .7551 .0244 O5 .77506 .71427 .8302 .0138 O6 .7815 .7375 .1941 .0212