#176
P63/m
Example – Fluorapatite, Ca5(PO4)3F
Named as the fluorine end-member and from the Greek apatao – “I am misleading.”
Structural variations in natural F, OH, and Cl apatites
Hughes J M, Cameron M, Crowley K D
American Mineralogist 74 (1989) 870-876
http://webmineral.com/data/Apatite-(CaF).shtml
CIF
http://rruff.geo.arizona.edu/AMS/download.php?id=01285.cif&down=cif
CaO6 or CaO5F strongly distorted octahedra
PO4 tetrahreda (orange)
F (green)
The Fascination of Crystals and Symmetry 