ZersiumCanonLegendsInfinitiesZersium was a mineral ore essential in the production of durasteel. The bedrock of the planet Nag Ubdur was flecked with zersium, which prompted the Galactic Empire to strip-mine the world. AppearancesDooku: Jedi Lost (First appearance) (Unknown)Unknown UnknownNoneDooku: Jedi Lost script (Unknown)Unknown UnknownNoneAftermath: Life Debt (First mentioned, simultaneous with audiobook) (Unknown)Unknown UnknownNoneAftermath: Life Debt audiobook (Mentioned only) (Unknown)Unknown UnknownNoneShadow of the Sith (Unknown)Unknown UnknownNoneShadow of the Sith audiobook (Unknown)Unknown UnknownNone