21 February 2019

Diamond type

Diamond type is a method of scientifically classifying diamonds by their chemical impurities. There are four types of diamonds: Type Ia, Type Ib, Type IIa, and Type IIb.



Types of Diamond

Type I diamonds contain nitrogen. It is the most common class, about 98% of all the diamonds are part of this group.

  • Type Iadiamonds are about 95% of all natural diamonds. These diamonds contain nitrogen atoms if clusters. They vary from near-colorless to light yellow.
    • Type IaA The nitrogen atoms are in pairs, and this doesn't affect its color.
    • Type IaB The nitrogen atoms are in the large group; these impart a yellow to brown tint.
  • Type Ib makes up about 0.1% of all natural diamonds. Nitrogen atoms are evenly distributed throughout the carbon lattice. These diamonds absorb green light and blue light and have a darker color than type 1a diamonds. They vary from deep yellow ("canary"), orange, brown to greenish.

Type II diamonds have no measurable nitrogen impurities

  • Type IIa diamonds make up 1–2% of all natural diamonds These diamonds are almost devoid of impurities, they are normally colorless but they can also be gray, light brown, light yellow or light pink. Among all diamonds, type IIa is chemically the purest.
  • Type IIb diamonds make up about 0.1% of all natural diamonds, making them one of the rarest natural diamonds and very valuable. These diamonds are known to conduct electricity Type IIb diamonds a light blue or grey color.

Are you considering a diamond purchase? Be sure that you understand the individual qualities of the diamonds 4Cs.

SOURCE: https://4cs.gia.edu/en-us/blog/digging-diamond-types