The Spirit Shards are magical items of light that were used to unseal Ashen's body after Verenrath had sealed it with black magic.
The First Spirit Shard was previously owned by a Golem that Korgen finds amid the forest. He defeats it in battle, and the Golem gives him the Spirit Shard.
The Second Spirit Shard was previously owned by Reiglash. Gerosin, after a skirmish, traded him a piece of metal for the Spirit Shard and left.
The Third and Final Spirit Shard was previously owned by Lezzen. Brendan defeated Lezzen in battle and confiscated the Spirit Shard.