What he ^ said. This is how they were made, by the thousands I would guess. Very cost effective. A bit tricky to strop, too.
I have seen quite a few of these Swedish framebacks on which the spine - the part covered by the tang that is - was blued/blackened or otherwise coated to prevent rust. Whenever I used one (I don't have one in use right now) I'd just blow the air out 'orally', as they say and leave it out to dry for a full day, as I do with all my razors.