Unique item

All artifacts are unique, but there are four objects which the game refers to as Unique Items (on the discoveries page):

• The Candelabrum of Invocation
• The Bell of Opening
• The Book of the Dead
• The Amulet of Yendor

Artifacts are not unique items, as they are a normal type of item with a special name. For example, the Eye of the Aethiopica is simply a named amulet of ESP.

Stormbringer and the Tsurugi of Muramasa are the only runeswords and tsurugis, respectively, in the game, but neither count as unique items, since it is possible to find non-artifact runeswords and tsurugis in a bones file, or wishing for them, while already having their artifact equivalent.