Azerothian diamonds are eternal.
As an ingredient
Azerothian Diamond is used in the following recipes:
As a quest objective
Azerothian Diamond was needed for the following quests:
- Patch 6.0.2 (2014-10-14): Stacks to 200, up from 20.
- Patch 1.5.0 (2005-06-07): Small Throrium Veins now sometimes will have Emeralds or Diamonds.