• Pendant of Endless Despair
• Item Level 219Disenchants into:
  [Abyss Crystal]: 1-2
• Binds when picked up
• Neck
• +58 Stamina
  +40 Intellect
• Requires Level 80
• Equip: Improves critical strike rating by 29.
  Equip: Restores 18 mana per 5 sec.
  Equip: Increases spell power by 70.
• Sell Price: 7 56 23

Source

This item drops from General Vezax in the 10-man version of Ulduar.

Patch changes

• Patch 3.1.0 (14-Apr-2009): Added. 
  

External links

• Battle.net (EU)
• Wowhead
• Thottbot
• WoWDB