Which fictional metal is used to forge the blade Narsil in Tolkien’s legendarium?

Tolkien does not specify a fictional metal used to forge Narsil.

Narsil is the sword wielded by Elendil, King of Gondor and Arnor, during the War of the Last Alliance. It breaks when Elendil falls in combat with Sauron. Isildur then uses the broken shard to cut the One Ring from Sauron’s hand. The sword is later reforged as Andúril for Aragorn.

Mithril is a famous Tolkien metal, but the texts do not identify it as Narsil’s material. Galvorn is another named metal in Tolkien’s mythology, associated with the First Age, not with Narsil. This question tests the difference between a canonical description of a weapon’s history and details supplied by adaptations or fan theories.