Close packed lattices

The left image is close packed Face Centered Cubic lattice. The right picture shows hexagonal close packed lattice (Mg, a-Co, a-Be).

Close packed lattices are formed by close packed planes (A is the blue and B is the gray ones below). You can put the third plane in two different ways - ABAB or ABCABC. C is formed by the red spheres (the third plane's spheres are reduced two times for convenience)
FCC and hexagonal lattices are very similar except for FCC includes a close packed plane of the third type (C plane - red balls). The C plane is shifted relative to the first A plane in FCC lattice.

3D Crystals models   Real Crystal lattices   Deffects of crystal lattices
updated 8 July 2001