cell 6.42 6.42 6.42 101.92 101.92 101.92
Titl Calcite (in cleavage rhombahedron
#N.B.  This is actually wrong.  This cell is not a true unit cell,
#      and only appears so as half the CO3 groups have been rotated 
#      by 60 degreed from their true orientations.  See DHZ.
atom Ca1  0.0    0.0    0.0
#  FCC Symmetry
symm x+1/2,y+1/2,z; x+1/2,y,z+1/2; x,y+1/2,z+1/2
atom C2   0.5     0.5     0.5
symm x+1/2,y+1/2,z; x+1/2,y,z+1/2; x,y+1/2,z+1/2
atom O1   0.1215 -0.1215   0.5
symm -x,0.5,x
symm 0.5,x,-x
dupl x+1/2,y+1/2,z; x+1/2,y,z+1/2; x,y+1/2,z+1/2
box 0.249
end