Eucryptite
Pillars W W, Peacor D R
American Mineralogist 58 (1973) 681-690
The crystal structure of beta eucryptite as a function of temperature
T = 23C
_database_code_amcsd 0000376
10.497 10.497 11.200 90 90 120 P6_422
atom     x     y     z Biso
Si1  .2486     0     0  .24
Si2  .2477 .4954     0  .34
Al1  .2520     0   1/2  .21
Al2  .2506 .5012   1/2  .24
Li1      0     0   1/2  3.0
Li2    1/2     0     0  3.6
Li3    1/2     0 .3240   .8
O1   .0853 .1942 .2428  .44
O2   .6023 .7008 .2651  .53
O3   .1101 .7099 .2597 1.06
O4   .5902 .2011 .2494  .66