Exhaust heat shield, paint?

Were the heat stoves painted black or were they black oxide? Either way they tended to rust.

Ok, feel the need to post again. Maybe I am confused but we are talking about two different items here. "Exhaust Shield" was install before exhaust manifolds and were an unpainted gasket and received over spray when engine was painted. "Exhaust Heat Stove" Was painted gloss black or dipped in paint and was installed after the engine was painted. Dave Moore's pristine low mileage original Duster 340 show the heat stove. The other picture is of my original exhaust shield removed from my untouched 340 engine. in second picture you can still see traces of blue paint on shield.