Celestial Orb

The Celestial Orb is Mage-only off hand item that gives a bonus to intellect and can restore mana.

Source
The Celestial Orb is a quest reward from the Mage quest which starts with Tabetha in Dustwallow Marsh.

Patch changes

 * Blizzard removed this item and quest's related on patch 4.0.3
 * Blizzard removed this item and quest's related on patch 4.0.3