How do ceramic crystal structures differ from metal crystal structures?

Metal crystal structures are much simpler than ceramic structures. This is due to two reasons. First, ceramics have positive and negative charged ions. Cations and ions must maintain charge neutrality. Second, the size of cations and anions are very different! Structures with multiple different sized ions can much more complex. This video showcases some of the different coordination environments that are possible depending on the ratio of cation to anion radii in the structure.