An allotrope of CARBON. It is the
hardest naturally occurring substance and
is used for jewelry and, industrially, for
cutting and drilling equipment. Each carbon
atom is surrounded by four equally
spaced carbon atoms arranged tetrahedrally.
The carbon atoms form a three-dimensional
network with each
carbon–carbon bond equal to 0.154 nm
and at an angle of 109.5° with its neighbors.
In diamonds millions of atoms are covalently
bonded to form a giant molecular
structure, the great strength of which results
from the strong covalent bonds. Diamonds
can be formed synthetically from
graphite in the presence of a catalyst and
under extreme temperature and pressure;
although small, such diamonds are of adequate
size for many industrial uses.
