Types Ia, Ib, IIa, IIb — scientific classification by impurities.
Type I vs Type II — scientific diamond classification.
Nitrogen aggregation — the most common natural diamond type.
Isolated nitrogen — significant for synthetic diamonds.
Low nitrogen — large and synthetically significant diamonds.
Boron-containing — blue diamonds and electrical conductivity.
Lattice defects that create color in diamonds.
Trade term for yellowish diamonds and its implications.