This shard can be found inside Ruins of Kardala dungeon in western Craglorn.
You can approach and enter Ruins of Kardala from south. You can spot the entrance to this dungeon from distance because of a lot of stone pillars standing in front of it. Shard is inside the room with boss Satagna. This room is a dead end on the side of the main hallway and you can easily pass it by as you try and reach the end of the dungeon, so stay alert.
Find and enter Ruins of Kardala.
Ruins of Kardala Entrance Map Location.
Find a dead end room.
Ruins of Kardala Entrance Shard Map Location.
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