A Mystic Code is... basically a tool a magus designed for a purpose. I don't think the jewels count--they're just containers for mana. The Jewel [i]Sword[/i], however, most certainly is (but that's in Zelretch's hands).

^ Azoth Dagger. [s]Also not a Mystic Code, it's just a really nice dagger.[/s] Huh, turns out it's made from jewels. So it [i]is[/i] one.