Rust-Proof

In The Forge of Virtue, Jordan Hawson possesses a bastard sword which has been enchanted with linear spellcraft. The actual name of the spell is not revealed. It is unknown if this spell can be cast in the convention sense, although it makes sense that it could.

Quote

 * "I don't know if we could fight harpies with swords."


 * Squirt's eyes swam with tears and he refused to grasp Jordan's outstretched, forgiving hand.


 * "Why not?" Drum demanded.


 * "They're left over from ancient times when sorcerers bred magic into their slaves and pets. They don't live the way natural things do--the way we do--and they don't always die. If I had a magic sword, but I don't. There's a little linear spellcraft in this--" Jordan touched the bastard-blade at his side, "--to help against rust but nothing to make it lethal. And that--" he confronted his brother who decided he still wasn't ready to stand up again "--that sticker will rust like pig-iron if you don't take care of it. Brandish a rusty sword at me, will you?"

- from The Forge of Virtue (Ultima Saga)