This quest is not available in game.
Bring a Libram of Focus, 1 Pristine Black Diamond, 4 Large Brilliant Shards, and 2 Skin of Shadow to Lorekeeper Lydros in Dire Maul to receive an Arcanum of Focus.
This libram almost aroused interest in one of the younger Lorekeeper's familiars. Poor thing, it was only a few weeks old.
Those among you who are more magically inclined might find this item interesting.
The Libram of Focus was lost in this wing. I can only assume one of the Highborne spirits holds it in their possession.
Bring the Libram along with some large brilliant shards, skin of shadow, and a pristine black diamond and I shall conjure the Arcanum.