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 = 484 C
_database_code_amcsd 0000380
5.251 5.251 11.192 90 90 120 P6_422
atom     x     y     z Biso
Si     1/2     0     0  .99
Al     1/2     0   1/2  .94
Li       0     0     0  7.1
O    .2105 .4046 .7456  2.4