The Silmarils were the precious jewels created from the light of the Two Trees of Valinor in J.R.R. Tolkien's legendarium. The Elven craftsman Fëanor made three jewels, preserving within them the radiance of Telperion and Laurelin.
The Silmarils are central to the mythology of The Silmarillion. Their beauty and sacred light make them objects of desire, but Fëanor’s oath to recover them drives generations of conflict among Elves, Men, and the forces of Morgoth. Morgoth steals the jewels and sets them in his crown.
They are not simply valuable gemstones. Tolkien gives them a near-sacred status, and their history connects the creation of the world, the rebellion of the Noldor, the First Age wars, and the eventual destruction of Beleriand.
The Arkenstone is another famous jewel in Tolkien’s writing, but it belongs to The Hobbit and is linked with Erebor. The palantíri are seeing stones, while the Elessar is a healing jewel. None of those objects contains the light of the Two Trees.