My textbook says that there are only 14 possible 3D lattices(Bravais Lattices). One of these 14 lattices is a hexagonal lattice in which only a primitive variation is given to be possible. But then I look at hexagonal closed packed structured lattice and I can't figure out how I could possibly make that lattice using primitive hexagonal unit cell. Am I missing something here? Source- NCERT class 12th part 1

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    $\begingroup$ Imagine two identical sheets of paper (say, A4). They are of the same shape, but the symbols you write on them can be very different. Same thing here. Atoms are your symbols. You may put them in the unit cell in a myriad of ways. $\endgroup$ Commented Apr 8, 2020 at 15:27
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    $\begingroup$ Indeed, hcp is not a primitive Bravais lattice. It has a 2-atom basis. $\endgroup$
    – Jon Custer
    Commented Apr 8, 2020 at 15:29


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