Part of the Sorcerer's Regalia 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 freezing the attacker in place for 3 sec. 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	Just Compensation Alliance Ironforge	Deliana Ironforge	9950 XP
60	Just Compensation Horde Orgrimmar	Mokvar Orgrimmar	9950 XP

Disenchants into

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