Topaz.
Description from the source:
Topaz (Al2 Si O4 (F OH)2 orth.), Perfect, transparent crystals with a bit of matrix. 2,6x2,1x1,5 cm; 10 g with box. Source:Simone Citon Contributor:John Gray Acquired:28 January, 2009 Text Updated:29 January, 2009 Price: Trade Size: 1" Composition:Al2SiO4(FOH)2