Sorceress Sellen's bell bearing, found upon her perished flesh. Offer to the Twin Maiden Husks at the Roundtable HoldLandmark to gain access to new items.

After completing almost all of Sorceress Sellen's quest steps and defeating Rennala, Queen of the Full Moon, fast travel to the Raya Lucaria Grand LibraryGrace Site of Grace. Right outside the entrance should be two summon signs. The red summon sign offers the option to challenge Sellen, where you will need to aid Witch-Hunter Jerren in defeating Sellen. Defeating Sellen will reward you with the Witch's Glintstone Crown and Sellen's Bell Bearing.