Ivory WatchstoneThe memories and emotions of countless victims of the Elder, locked in stone for eternity.Socket this into a Citadel on your Atlas to increase the Tier of Maps and reveal hidden Maps in that Citadel's Region. You can only socket one Crimson, Viridian, Cobalt or Golden Watchstone into each Citadel.
Acquisition Not in game Drop level: 1 Ivory Watchstone also drops as a unique item. It drops from Sirus.Metadata Item class: Watchstone Metadata ID: Metadata/Items/AtlasUpgrades/AtlasRegionUpgradeFinal
Ivory Watchstone always drop as a unique. It is not possible to obtain non-unique version as Ivory Watchstone or other craftable watchstone cannot be corrupted into rare by using a Vaal OrbVaal OrbStack Size: 20Corrupts an item, modifying it unpredictablyRight click this item then left click an item to corrupt it. Corrupted items cannot be modified again., thus it is not able to use the 5 to 1 recipe to obtain a not-corrupted rare version.
Since the game dev removed the watchstone system entirely. It is not possible to obtain any Ivory Watchstone, even in the permanent leagues.