Going by mine and some others I've seen...
Non-matching numbers; parts mixed up between years/factories; missing cleaning rod and front sight hood; plenty of dings and dents from service on the eastern front; heavy, dark black re-bluing job with a goldish-plum colored extractor; thick, goopy dark reddish cosmoline grease hanging off the rifle in globs and packed into every crevice.
My rifle looks like it's gone through hell and back but that's all just part of the character... When you pick it up it still feels like a tough, well-built firearm. The bore is immaculate, and it's overall a real joy to shoot. Will probably never get rid of that rifle!