Well, the Novus is i110 and the Ironworks is i120...so, uh, duh, the ironworks has higher stats?

The Longinus (zodiac version of your relic) is going to have higher stats than the base Ironworks weapon, and the Augmented Ironworks will beat out the Longinus. If we get a Longinus Zenith at some point, it will probably beat out the Augmented Ironworks.