Location: This quest takes place in Arathi Highlands. Follow up on Quest: The Princess Trapped.
Shortly: Iridescent Shards in Drywhisker Gorge wants you to gather the Burning Key, the Crescent Key and the Thundering Key.
How to: Visit circles of east, outer and west bindings shown in the below map and click the stones at the center of the circle of each one. This will give you a key from each one. After getting all 3 keys you need to bring them to the Circle of Inner Binding also shown below. Click the stone on the side of the circle and end the quest.
The Rewards are 50 silvers.