InNorse mythology,Andvaranaut (12th c.Old Norse:[ˈɑndˌwɑrɑˌnɔut]), meaningAndvari's Gem ("Andvari's precious possession"), is amagic ring, initially owned byAndvari, that could help with finding sources of gold.^{[citation needed]}

Themischievous godLoki stole Andvari's treasure and the ring. In revenge, Andvari cursed the ring to bring misfortune and destruction to whoever possessed it. Loki quickly gave the cursed Andvaranaut toHreidmar, King of theDwarves, asreparation for having inadvertently killed Hreidmar's son,Ótr. Ótr's brother,Fafnir, then murdered Hreidmar and took the ring, turning into adragon to guard it.Sigurd (Siegfried) later killed Fafnir and gave Andvaranaut toBrynhildr (Brünnehilde). QueenGrimhild of theNibelungs then manipulated Sigurd and Brynhildr into marrying her children, bringing Andvaranaut's curse into her family.^{[citation needed]}

Richard Wagner used Andvaranaut as inspiration for the title of his musical dramaDer Ring des Nibelungen.J.R.R. Tolkien may have been inspired by Andvaranaut when designing theOne Ring, both by making the One Ring cursed and by making one of its aspects to allow the wearer to find the otherRings of Power, knowing the location of the wearer of each of the Rings of Power, so that the wearer of the One Ring could control these Ringbearers.

• Rings in early Germanic cultures