Currently completed (week 1) in Vale, these are found around the bases of the large tentacles around the lake between the shrines. There are between 1 and 3 around the base of each tentacle and more than enough to complete the quest.
With flying you can avoid many of the mobs and just fly down above the shards, click, mount, fly up.
Edit: When found in Uldum (week 2), these are just strewn around the grass. I found them in the grass North-East of Ramkahen between the edge of the corruption and the rivers edge, in among all the portals and void creatures. A little more difficult to avoid pulling anything but easy to avoid pulling the large patrolling faceless mobs.
Note that these were a lot more visible and they may have turned the glow around them up to make them easier to see. They were also sporadic, some singular and some in nearby groups of 2-3. Still a very easy quest, just a lot closer to the quest giver.