#45
Iba2
Example – Banalsite, BaNa2Al4Si4O16
Named from a contraction of the component cation symbols: Ba, Na, Al, and Si. It belongs to the group of tectosilicates.
The crystal structure of stronalsite and a redetermination of the structure of banalsite.
Liferovich R P, Locock A J, Mitchell R H, Shpachenko A K
The Canadian Mineralogist 44 (2006) 533-546
http://webmineral.com/data/Banalsite.shtml
CIF
http://rruff.geo.arizona.edu/AMS/download.php?id=06594.cif&down=cif
BaO10 irregular polyhedra (green)
NaO5 pentagonal pyramids (yellow)
AlO4 tetrahedra (blue)
SiO4 tetrahedra (orange)