Capturing the Phylactery

Objectives
Recover Naberius's Phylactery from Kirin'Var Village's Chapel Yard district and bring it to Custodian Dieworth.
 * Naberius's Phylactery

Description
I suppose an explanation is in order. You've met one of the archmage's apprentices, Ravandwyr, but there was also another named Naberius. He was an ardent student, but was drawn to necromancy. When Kael'thas appeared with his forces, Naberius seized the opportunity to betray the archmage, handing over the secrets to the tower's defense. Now, it seems, he has become a lich. If we are to stop him, we must capture his phylactery. Knowing him, he would've buried it somewhere out of sight in his domain.

Reward
You will receive:

Progress
You must recover Naberius's phylactery before we can attack him. Otherwise, he will be invulnerable.

Completion
Excellent work, &lt;name&gt;. Possession of the phylactery will be the key to our victory. When you enter battle with Naberius, I will smash it, exposing him to your attacks.

Gains
Upon completion of this quest you will gain:
 * 12300 XP (or at level 70)