Diamond is one of the best-known and most sought-after gemstones.
Crystal structure
The most common crystal, tructure of diamond is called diamond cubic. It is formed by elementary cells, stacked together. The length of each side of the elementary cell is denoted by the letter a and is 3.567 angstroms.[17]The distance to the nearest neighbor in the diamond lattice is 1.732a/4, where a is the lattice constant, usually expressed in angstroms as a = 3.567 Å, which is 0.3567 nm.
