Solfatara Residue

 is a Bone.

Obtaining

 * Dropped by
 * Solfatara

Uses

 * Used in the craft of
 * Key to the Obsidemon's Hypogeum
 * Obsidemon Ring
 * Obsidemon Cloak
 * Obsidemon Amulet
 * The Maidartes
 * Sandals Bino
 * Pants Fordamemory
 * Cape Tivate
 * Bim Bonnet
 * Postapocalypse Hat
 * Unchewa Staff
 * Sternutatory Wand
 * Walloping Hammer