The space lattice of diamond is:
The diamond lattice consists of a face-centred cubic Bravais point lattice which contains two identical atoms per lattice point.
The distance between the two atoms equals one-quarter of the body diagonal of the cube. The diamond lattice represents the crystal structure of diamond, germanium and silicon.
The diamond lattice contains also 4 lattice point per unit cell but contains 8 atoms per unit cell tetrahedrally bonded atoms in each primitive cell.