Of The Simarils

Fëanor created the Silmarils during the Years of the Trees in the Noontide of Valinor. They were named for and crafted of the hard crystalline substance silima, and contained some of the light from the Two Trees of Valinor made by Yavanna and Nienna-named Telperion the Silver, and Laurelin the Gold. Recognizing their immense beauty, they were hallowed by Varda, Queen of Arda so that no mortal flesh, hands unclean, or anything evil could touch them. Before Melkor began stirring up trouble amongst the Ñoldor, Fëanor would often wear them blazing on his brow at feasts and would allow others to see them, but as he began to suspect his kin he no longer displayed them openly allowing only his father and sons to view them. After Fëanor was exiled to Formenos, the Silmarils were stored in a chamber of iron.
Together with Ungoliant, Melkor destroyed the Two Trees. The Silmarils now contained all the remaining light of the Two Trees. Therefore, the Valar entreated Fëanor to give up the Silmarils so they could restore the Trees, but he refused. Then news came: Melkor had killed Fëanor's father Finwë, the High King of the Ñoldor, and stolen all the gems, including the Silmarils. After this deed, Melkor fled to the northlands of Middle-earth, where his ancient fortress was. Melkor, now named Morgoth by Fëanor, set the Silmarils in his crown.
Fëanor was furious at Melkor and at the Valar's perceived desire to take the gems for their own purposes, and, swearing that he and his sons would not rest until the Silmarils were recovered, he led the Ñoldor back to Middle-earth. His flight, which began the First Age of Middle-earth, led to no end of grief for the Elves and eventually for the Men of Middle-earth. Five major battles were fought in Beleriand, but ultimately the Ñoldor failed.
One of the Silmarils was recovered by Beren and Lúthien through great peril and loss. This stone was later taken by Eärendil to the Valar in the West as a token of repentance. The Valar then set this Silmaril as a star. The other two gems remained in Morgoth's hands, and were taken from him only at the end of the War of Wrath. However, soon afterwards, they were stolen by Fëanor's two sons Maedhros and Maglor. The jewels burned their hands, in refusal of their rights of possession, as they had burned Morgoth's hands many years before. In agony, Maedhros threw himself and his Silmaril into a fiery pit, and Maglor threw his into the sea. Thus, the Silmarils remained in all three elements of Arda — in the sky, fire and water