The three Silmarils were set into the Crown, fastened by iron claws. In the Quest for the Silmaril, as told in the tale "Of Beren and Luthien", Beren pried one Silmaril loose from the crown using his knife.  After Morgoth's defeat in the War of Wrath, the other two jewels were removed, and the crown was beaten into a collar for his neck.
In the Third Age, during the Witch-king's campaign against Arnor, he wore an Iron Crown, and his supporters often called him "The Iron Crown" or "The King of the Iron Crown".
- ↑ The Silmarillion, Quenta Silmarillion, Chapter XIX: "Of Beren and Lúthien"
- ↑ The Silmarillion, Quenta Silmarillion, Chapter XXIV: "Of the Voyage of Eärendil and the War of Wrath"