Osumilite
Armbruster T, Oberhansli R
American Mineralogist 73 (1988) 585-594
Crystal chemistry of double-ring silicates: Structural, chemical, and optical
variation in osumilites
Sample: Antarctica
_database_code_amcsd 0001149
10.086 10.086 14.325 90 90 120 P6/mcc
atom      x      y      z occ U(1,1) U(2,2) U(3,3) U(1,2) U(1,3) U(2,3)
KC        0      0    .25 .91  .0255  .0255   .031 .01275      0      0
FeA     1/3    2/3    .25 .01  .0054  .0054  .0107  .0027      0      0
MgA     1/3    2/3    .25 .99  .0054  .0054  .0107  .0027      0      0
Si1  .24821 .35359 .39206 .86  .0086  .0099  .0077  .0055  .0015  .0017
Al1  .24821 .35359 .39206 .14  .0086  .0099  .0077  .0055  .0015  .0017
Fe2      .5     .5    .25 .01  .0091  .0091  .0068  .0072      0      0
Al2      .5     .5    .25 .99  .0091  .0091  .0068  .0072      0      0
O1    .1229  .4079      0       .026   .020  .0072   .011      0      0
O2    .2166  .2847  .1320       .028   .035  .0228  .0244 -.0017 -.0048
O3    .1398  .4934  .1790      .0138  .0155  .0117  .0087 -.0037 -.0049