The dispersed nitrogen atoms in type Ib diamonds result in unique optical properties. These diamonds not only absorb blue light like type Ia diamonds but also absorb green light, resulting in a deeper and more intense yellow or brown colour compared to type Ia diamonds.
It is noteworthy that type Ib diamonds are highly valued for their unique colour characteristics and rarity. The term “canary diamonds” often refers to these vivid yellow stones, reflecting their exceptional beauty and desirability.