Mithril gets an origin story in 'The Lord of the Rings: The Rings

Episode 4 of "The Lord of the Rings: The Rings of Power" reveals that the dwarves of Khazad-dûm have been mining mithril in secret.

Why the Elves Want Mithril on THE RINGS OF POWER - Nerdist

The Rings Of Power's Mithril Reveal Explains 6 Lord Of The Rings

Is The Song of the Roots of Hithaeglir True from The Rings of Power?

Where Did Mithril Actually Come From?

Does this check out lore-wise? : r/lotrmemes

What Are the Rings of Power? The History & Abilities of Tolkien's

Did 'Rings of Power' Retcon Míthril? Explained

Why The Rings of Power Created a Non-Tolkien Origin Story for Mithril

The Rings of Power Ending Explained and What to Expect in Season 2