This is one of 7 Crystals that can drop with a very low chance. Not sure if they're tied to locations. Each one provide a strong buff for 30 minutes.

Buffs:

Attack Speed +50% & Casting Speed +50%
Movement Speed +50%, Fall Damage Reduction +50%, Jump Height +2m
Greatly increases Attack Power
Greatly increases Defense Power
Summons an object that heals targets in an area
Summon an object that attacks an area
Summon an object that reduces Movement Speed in an area