The One Ring?

[The Squatter of Amon Rûdh]

Annoyingly, all I've been able to turn up is from Unfinished Tales, in the form of a note from Christopher Tolkien:

The time and place of Celebrian's birth, whether here [Lake Nenuial] or later in Eregion, or even later in Lorien, is not made definite.

(Concerning Galadriel and Celeborn)

Since that timing and location would be absolutely critical in addressing onewhitetree's question, I'm more than a little piqued by this, although if it helps, Amroth was born at Lake Nenuial between 350 and 400 SA according to the same source.