Gurthang was originally Anglachel, a sword forged by Eöl, the Dark elf of Nan Elmoth. The "reforging" by the smiths on Nargothrond was years later after Beleg Cúthalion requested the sword from Thingol against the warnings of Melian the Mia. After Turin slew Beleg, his friend, Gwindor the saved the sword and later presented it to Turin when he came to his senses.
Anglachel was re-forged by the expert smithies at Nargothrond, and was renamed by its new keeper, Túrin, to Gurthang, which means Iron of Death, or Wand of Death. The blade was black but its edges shone with pale fire. The Orcs and Elves call the weapon, and Túrin, "Mormegil", signifying Black Sword. Gurthang was used by Tûrin to slay Glaurung. When Túrin discovered that Nienor Níniel was his sister, Nienor, and that she had killed herself, Tûrin in despair fell upon Gurthang, committing suicide. It is interesting to note that the sword seemed to have a will of its own and spoke to its owner on at least one occasion.
- "Hail Gurthang! No lord or loyalty dost thou know, save the hand that wieldeth thee. From no blood wilt thou shrink. Wilt thou therefore take Túrin Turambar, wilt thou slay me swiftly?"
- —Túrin to Gurthang
- "And from the blade rang a cold voice in answer: 'Yes, I will drink thy blood gladly, that so I may forget the blood of Beleg my master, and the blood of Brandir slain unjustly. I will slay thee swiftly."
- —Gurthang to Túrin