Way to unlock: Talk to Iron Bull in Skyhold, you must be in relationship with this companion.
The quest-giver: Iron Bull (M12,22)
Talk to Iron Bull (M12,22) in Skyhold. You must be in relationship with him. During the conversation in the tavern ask him about the seriousness of relationship and keep the conversation until you receive Kadan necklace receipt.
Now you must kill a dragon - or if you done it already - have an item: dragon teeth. It is the first item required for creating the necklace, second is 1x obsidian.
If you have both items, go to any order table to create the necklace. Then return to Iron Bull in Skyhold and give him the necklace, after a cutscene quest will end.
Rewards for completing the quest:
- Experience (few)
- 80 influence points