In Game Description
Ember required for weapon ascension.
Crystal ember created by Seath the Scaleless.
Handled only by the giant God's blacksmiths.
Ascends +10 standard wpn to crystal weapon.
(crystal weapons can be reinforced to +5)
Crystal weapons are powerful but brittle,
and cannot be repaired once broken.
Found in The Duke's Archives in the room near the lever that needs to be operated to open a staircase to the Crystal Cave area
It is in a chest between the rows of bookshelves
Allows ascension of +10 Normal weapons to the Crystal upgrade path, up to +5 Crystal (Giant Blacksmith)