Acquiring a Royal Seal of Eldre'Thalas
The books need to be returned to either (Hunter, Warlock, Paladin), (Druid, Priest, Shaman), or (Rogue, Warrior, Mage) in the Athenaeum (Also referred to as the Library) in Dire Maul. The easiest way to get here is by taking the north entrance to Dire Maul, heading down the ramp into the open area then taking the double doors to your left, which lead to the library.
- Note that you must have Crescent Key from Dire Maul: East to open the double doors, or have an appropriate lockpicking skill (300), or use a Powerful Seaforium Charge or better.
Aside from 10 Fire Resistance, each trinket gives a bonus based on the class the trinket is for.
As of patch 1.10 the quests are no longer repeatable.
There is no Death Knight Seal because they were not out when this was released. This is not likely to change.