The Medallion Half 1, The Two Trees of Valinor artifact can be found at Celon Poros, in the western part of Sea of Núrnen.
Shattered Medallion Half, The Two Trees of Valinor, Second Age, circa 3430
Across Mordor the Two Trees of Valinor are recognized as a symbol of the light of creation and of the ancient bond between Elves and Men. This medallion half, crafted by the Elves, commemorates the original two trees of legend, whose scions now survive only in the White Tree of Gondor.
"All right… hold still. I'm afraid to say, it's going to…
…it's going to hurt.
I've done all I can. We've called for one of your people, but I don't… in the meantime, why don't you tell me about that? The medallion you're holding…
You just want to distract me. Very well. These are the Two Trees of Valinor… a symbol of the endless cycle: Life, death, and rebirth. Come closer, and I will tell you their tale. We must…
…I fear we must distract ourselves from the grim happenings of this day."