The second ring, Nenya, was made of mithril and adorned with a "white stone", presumably a diamond. The name is derived from the Quenya nén meaning water. It is also called Ring of Adamant, Ring of Water and the White Ring.
The ring is wielded by Galadriel of Lothlórien, and possesses radiance that matches that of the stars; while Frodo Baggins can see it by virtue of being a Ring-bearer, Samwise Gamgee tells Galadriel he only "saw a star through your fingers". (This appears in many editions as "finger"—which sounds more magical, since it suggests that her finger has somehow become transparent—but The Treason of Isengard, ch. 13, note 34, mentions it as an error.)
Nenya's power gave preservation, protection, and possibly concealment from evil because "there is a secret power here that holds evil from the land". However, the fact that Orcs from Moria entered Lórien after The Fellowship of the Ring and Lórien itself had suffered previous attacks from Sauron's Orcs sent from Dol Guldur suggests the power of the ring did not constitute military prowess. It was said that, protected as it was by Nenya, Lothlórien would not have fallen unless Sauron had personally come to attack it. Galadriel used these powers to create and sustain Lothlórien, but it also increased in her the longing for the Sea and her desire to return to the Undying Lands.
After the destruction of the One Ring and the defeat of Sauron, its power faded along with the other Rings of Power. Galadriel bore Nenya on a ship from the Grey Havens into the West, accompanied by the other two Elven Rings and their bearers. With the ring gone, the magic and beauty of Lórien also faded along with the extraordinary mallorn trees (save the one that Samwise Gamgee grew in Hobbiton that lived for centuries) and it was gradually depopulated, until by the time Arwen came there to die in F.A. 121 it was deserted and in ruin.
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