1. If the new primitive cell has the same general shape, then it represents the same
general lattice.
2. If no new primitive cell is found, then the resulting non-primitive lattice must be
recognized as a new lattice type.
Fig. 1.19 Derivation of 3D-lattices from 2D-lattices
1.4 Centering in 2-D and 3-D Crystal Lattices
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