The Storm Shard is obtained by .... On top of the first mountain near the town. Follow the road out of town and turn right, right before the Cemetery and go off road for a bit you will see a path leading up the mountain. Jumping is required and I suggest you take your armor off, run and jump into the dark alcove above golem go all the way up watch out for the pit at the top go to where you can see the sea and town and ... Bam! Right there on the ground :)
The following spells are available when using this shard:
Glow - conjures an orb that float over you and lights nearest 3-4 meters for 30 seconds.
Arc - long range lighting bolt, deal 19 dmg, uses 20 Ikhor.
Lighting - fast moving lighting ball, deal 7 dmg, uses 10 Ikhor.