Cultural question ... Anyone? I'm still interested!

About halfway through the movie, After TJ and Uncle Black get a ride from the constable, they're at a roadside diner when a van full of Aboriginal men pulls up. They are covered with white (clay?/paint?). Just wondering the significance of the covering, or the associated custom.

Thanks

"In a time of universal deceit,
telling the truth is a revolutionary act."
George Orwell