#164
P-3m1
Example – Portlandite, Ca(OH)2
Named because the material is a common product of hydration of portland cement.
A nuclear magnetic resonance determination of the hydrogen positions in Ca(OH)2, T = 25 °C
Henderson D M, Gutowsky H S
American Mineralogist 47 (1962) 1231-1251
http://www.webmineral.com/data/Portlandite.shtml
CIF
http://rruff.geo.arizona.edu/AMS/download.php?id=00189.cif&down=cif
CaO6 octahedra (blue)
The Fascination of Crystals and Symmetry 