Stone of Eärendil

A powerful gem said to have been created by Enerdhil in Gondolin; a green stone filled with sunlight, it had the powers of healing and restoration. It was given by its maker to Idril Celebrindal, and when Idril left Middle-earth she passed it on to her son Eärendil. When he went to sea, Eärendil wore the green stone on his breast, and so when he found Aman at last, the Elessar was lost to Middle-earth.

In the Third Age, a second Elessar was seen in the Mortal lands, and some said that this was the original Stone of Eärendil, brought back across the Great Sea by Gandalf. This is uncertain, and other sources suggest that this Elessar was a new stone of lesser power, created by Celebrimbor in Eregion. If this latter story is true, then the Stone of Eärendil remained in the West, still borne by the great Mariner from whom it took its name.