Depends on which wheel you have. Steel's with hubcaps would be natural, Rally's would have a black face.
Here is how the drums were painted on my low mileage '72 Skylark. Just as described by the guys above, only the front face had a light coat of shiny black paint. This car had all 4 drums painted but it was ordered with full hubcaps so it wasn't supposed to be painted, but it was. All of the unpainted parts of the drums have a light layer of surface rust.
If you look closely, you can see dripping off the sides which means they were painted when they were flat and not on the car.
The wheel studs are painted black and the drum retaining clip was also painted black so they appear to have been on the chassis when painted. The grease cap up front was also painted black.
Guys, If you look in the assembly manual on page 2-2.1 it shows a completed chassis assembly and calls out the areas the engineers wanted painted black. Now this work was done before the body was dropped onto the chassis. We know it was done this way because when the rear axle was painted the shocks were already installed, as they were painted black at the bottom. It also made sense to paint everything after it was installed so there was no paint chipping/touch up required, and remember the black paint was only supposed to last until the car left the lot. So only for a couple of months, with test drives etc. Anything longer then that was pure cream. Duane PS, even the tailpipe ends were originally painted black.
