Part of the Vestments of the Virtuous set:

The set gives these bonuses as more pieces are worn: 2: +8 All Resistances. 4: When struck in combat has a 2% chance of shielding the wearer in a protective shield which will absorb 488 damage. Can only occur once every 60 sec. 6: Increases damage and healing done by magical spells and effects by up to 23. 8: +200 Armor. Set Details | All Sets

Quest Reward from:

Level	Name	Start	Rewards
60	An Earnest Proposition  (Dungeon) Horde and Alliance Ironforge	Deliana Ironforge	6600 XP
60	An Earnest Proposition  (Dungeon) Horde Orgrimmar	Mokvar Orgrimmar	6600 XP

Disenchants into

Name	Value	Drop%
Large Brilliant Shard	1 Copper	99.0%
Nexus Crystal	1 Copper	1.0%