Last of the Seven

One of the Seven Rings of the Dwarves, forged in Eregion and said to have been unique in that it was a gift of the Elves to the Dwarves (the other six were presented to their holders by Sauron). According to tradition, it was originally given by Celebrimbor to his friend Durin III of Khazad-dûm in the middle of the Second Age. It remained in the keeping of the royal line of Durin's Folk throughout that Age and into the closing centuries of the Third.

As the years passed, Sauron sought to reclaim the Seven Rings, and by about III 2790¹ six of them were back in his grasp, or known to have been destroyed. The Ring of Durin's line was the last to remain in the hands of the Dwarves. It was held at that time by Thrór, rebuilder of the Kingdom under the Mountain, and thus was commonly known as the Ring of Thrór.

Thrór passed the Ring to his son Thráin (father of Thorin), who in time decided to set out to revisit the Lonely Mountain, from which he had been driven by Smaug. He never completed that journey; instead he was ensnared by Sauron the Necromancer and imprisoned within Dol Guldur. There his Ring was taken by Sauron, the Last of the Seven to be lost to the Dwarves.