The chunk of crystal is a quest item used during the Legends' Quest. It is obtained by killing one of three knights--Ranalph Devere, Irvig Senay or San Tojalon—in the dungeon under Kharazi Jungle. When combined with the lump of crystal, and the hunk of crystal (obtained by killing the other two knights), they form the heart crystal required to unlock a door leading further into the dungeon.