Mithril

Mithril, the legendary silvery metal rarer and more precious than gold, is introduced in The Fellowship of the Ring as a Moria-exclusive treasure, lighter and stronger than steel, captivating the Fellowship with its untarnishable beauty. Discovered adorning the Chamber of Mazarbul, it becomes a pivotal element when Bilbo gifts his mithril shirt to Frodo, saving his life multiple times across the series. Though its prominence wanes after the first book, the shirt's protective legacy endures through The Two Towers and The Return of the King, symbolizing Elven craftsmanship amid the quest's escalating perils.