Type II diamonds are one of the rarest and most valuable types of diamonds in the world. They are less common than Type I diamonds and are known for their unique characteristics, including their lack of nitrogen impurities and their distinct crystal structure. In this comprehensive guide, we'll explore the world of Type II diamonds, including their different types, characteristics, rarity, grading and certification, and buying considerations.

What are Type II Diamonds?

Diamonds are classified into two types, Type I and Type II, based on the presence or absence of nitrogen impurities in their crystal structure. Type II diamonds are less common than Type I diamonds and are known for their unique characteristics. They are further classified into two subtypes, IIA and IIB, which differ in color and electrical conductivity.

Types of Type II Diamonds

Type II diamonds are further divided into two subtypes: IIA and IIB. IIA diamonds are characterized by their lack of nitrogen impurities and colorlessness, while IIB diamonds are known for their boron impurities, which give them a blue color. IIB diamonds are also electrically conductive, while IIA diamonds are not.

Characteristics of Type II Diamonds

Type II diamonds are characterized by their lack of nitrogen impurities in their crystal structure. Instead, they may contain other types of impurities, such as boron, hydrogen, or nickel. This absence of nitrogen impurities also affects their crystal structure, making them distinct from Type I diamonds. Type II diamonds are often found in large sizes and are known for their exceptional clarity and brightness.

Rarity and Value

Type II diamonds are much rarer than Type I diamonds and account for only about 1% of all diamonds mined. Due to their rarity, they are highly valued and can command premium prices in the market. Some of the most famous diamonds in history, such as the Cullinan II and the Koh-i-Noor, are Type II diamonds.

Grading and Certification

Like all diamonds, Type II diamonds are graded and certified by organizations such as the Gemological Institute of America (GIA). However, the grading process for Type II diamonds is different from that of Type I diamonds. Since they have a different crystal structures, the grading criteria used for Type II diamonds are adjusted accordingly. It's important to ensure that any Type II diamond you purchase comes with proper certification to ensure its authenticity and value.

Buying Considerations for Type II Diamonds

When buying a Type II diamond, there are several factors to consider. The most important factors are the cut, color, clarity, and carat weight of the diamond. The cut is especially important as it affects the diamond's overall brilliance and beauty. Type II diamonds may also be more expensive than Type I diamonds, so it's important to do your research and ensure that you are getting a high-quality diamond that meets your needs and preferences.

Conclusion

Type II diamonds are a rare and valuable type of diamond that are known for their unique characteristics, such as their lack of nitrogen impurities and distinct crystal structure. If you are in the market for a Type II diamond, it's important to understand the different types, characteristics, rarity, grading and certification, and buying considerations to ensure that you make an informed decision. By doing so, you can find a Type II diamond that will be a treasured and valuable addition to your jewelry collection.