Ceramic - Boron nitride
Background
Boron nitride is a synthetic material, which although discovered in the early 19th century was not developed as a commercial material until the latter half of the 20th century. Boron and nitrogen are neighbours of carbon in the periodic table - in combination boron and nitrogen have the same number of outer shell electrons - the atomic radii of boron and nitrogen are similar to that of carbon. It is not surprising therefore that boron nitride and carbon exhibit similarity in their crystal structure.
In the same way that carbon exists as graphite and diamond, boron nitride can be synthesised in hexagonal and cubic forms.
