Diamond Classification Flashcards
How are diamonds classified by their impurities?
Type I and Type II
What is a Type I Diamond
Type I diamonds are diamonds that contain nitrogen.
What is a Type II Diamond
Type II diamonds contain no significant amount of nitrogen.
What are the classification for Type I
Type Ia
Type Ib
What are the classification for Type Ia
Type IaA
Type IaB
Type IaAB
What is Type Ia
Nitrogen atoms are present as pairs or small groups called aggregates
What is Type Ib
Nitrogen atoms are present as isolated atoms
What is Type IaA
Contain aggregates of two nitrogen atoms, A aggregates
What is Type IaB
Nitrogen is present as aggregates of four nitrogen atoms surrounding a ‘vacancy’ B aggregates. (Most diamonds containing some nitrogen in the B form also have aggregates of three nitrogen atoms surrounding a vacancy.
What is Type IaAB
Type IaAB - Contain both the A and B forms of nitrogen with a mixture of A and B aggregates.
Type IIa
Contain no significant impurities, no sharp absorption in the visible region and is capable of conducting electricity.
Type IIb
boron atoms are present as an impurity and is not capable to conduct electricity.
What is a trace element?
Element that occurs in minute quantities.
Why classify?
According to their impurities.
What is the most common impurity?
Nitrogen is the most common impurity of a diamond.
