Mithril was a precious silvery metal, stronger than steel but much lighter in weight, which was mined by the Dwarves in the mines of Khazad-dûm. The name Mithril came from two words in Sindarin—mith, meaning "grey", and ril meaning "glitter". Mithril was also called "true-silver" by Men, while the Dwarves had their own, secret name for it.
The wizard Gandalf explained mithril to the Company, passing through Khazad-dûm, the Mines of Moria:
- "The wealth of Moria was not in gold and jewels, the toys of the Dwarves; nor in iron, their servant... Its worth was ten times that of gold, and now it is beyond price; for little is left above ground, and even the Orcs dare not delve here for it.
- "Mithril! All folk desired it. It could be beaten like copper, and polished like glass; and the Dwarves could make of it a metal, light and yet harder than tempered steel. Its beauty was like to that of common silver, but the beauty of mithril did not tarnish or grow dim." (The Fellowship of the Ring, "A Journey in the Dark").