Ohh the Iron[oxide]y

Via

And that's irony in and of itself that we're talking about irony involving Iron Oxide. Stupid chemistry - why did I learn so much about it?

By the way I remember this: Rust consists of hydrated iron(III) oxides Fe2O3·nH2O and iron(III) oxide-hydroxide FeO(OH)·Fe(OH)3. (Source)