I finally managed to take a few shots of my 1909. You can clearly see the center band is blued if you look at the photo showing the band springs. There is a scratch on the band down to the white causing a contrast. I hope this helps you in some way.
To recap: butt plate, entire bolt and all its components, receiver, cleaning rod, bayonet lug & pin and stock cap under front band all in the white. Everything else is blued.
Edit: if your rifle was made there or went through an Argentinemilitary refurb none of the components in the white would still be. Only untouched DWM rifles should look like this.